/kastus k „,«■ HUMAN FACTORS ENGINEER!! IXO TILECOHPUTING SYSTEM new small computer lat won't limit you tomorrow New Cromemco System One shown with our high-capability terminal and printer. mmmnmm mm mm wmkmkm^iSM^ JBFJmwmw mm mm HI ^^^fe^k mm mm HHHHflHBHHHI Expandability Here's a low-priced computer that won't run out of memory capacity or expandability halfway through your project. Typically, computer usage tends to grow, requir- ing more capability, more memory, more storage. Without a lot of capability and expandability, your computer can be obsolete from the start. The new System One is a real building-block machine. It has capability and expandability by the carload. Look at these features: ■ Z80-A processor ■ 64K of RAM ■ 780K of disk storage ■ CRT and printer interfaces ■ Eight S-100 card slots, allowing expansion with — color graphics — additional memory — additional interfaces for telecommunica- tions, data acquisition, etc. ■ Small size GENEROUS DISK STORAGE The 780K of disk storage in the System One Model CS-1 is much greater than what is typically available in small computers. But here, too, you have a choice since a second version, Model CS-1H, has a 5" Winchester drive that gives you 5 megabytes of disk storage. MULTI-USER, MULTI-TASKING CAPABILITY Believe it or not, this new computer even offers multi-user capability when used with our advanced CROMix* operating system option. Not only does this outstanding O/S support multiple users on this com- puter but does so with powerful features like multi- ple directories, file protection and record level lock. CROMix lets you run multiple jobs as well. in addition to our highly-acclaimed cromix, there is our CDOS*. This is an enhanced CP/M f type system designed for single-user applications, cp/m and a wealth of CP/M-compatible software are also available for the new System One through third- party vendors. COLOR GRAPHICS/WORD PROCESSING This small computer even gives you the option of outstanding high-resolution color graphics with our Model SDI interface and two-port RAM cards. Then there's our tremendously wide range of Cromemco software including packages for word processing, business, and much more, all usable with the new System One. ANTI-OBSOLESCENCE/LOW-PRICED As you can see, the new One offers you a lot of performance. It's obviously designed with anti- obsolescence in mind. What's more, it's priced at only $3,995. That's considerably less than many machines with much less capability. And it's not that much more than many machines that have little or nothing in the way of expandability. Physically, the One is small — 7" high. And it's all- metal in construction. It's only 14Ve" wide, ideal for desk top use. A rack mount-option is also available. CONTACT YOUR REP NOW Get all the details on this important building-block computer. Get in touch with your Cromemco rep now. He'll show you how the new System One can grow with your task. * CROMIX and CDOS are trademarks of Cromemco Inc. tCP/M is a trademark of Digital Research ra Cromemco TM ^^^« 280 BERNARDO AVE., MOUNTAIN VIEW, CA 94040 • (415)964-7400 Tomorrow's computers today T 7 ■ m CROMIX* — Cromemco's outstanding UNIX— like operating system is just the kind of major Dment you've come to expect trom Cromemco. After all, we're already well-known for the most respected software in the microcom- puter field. And now we've come up with the in- dustry's first UNix-lookalike for microcomputers. It's a tried and proven operating system. It's available on both 5" and 8" diskettes for Cromemco systems with 1 28K or more of memory. Here are just some of the features you in this powerful Cromemco system: • Multi-user and multi-tasking capability » Hierarchical directories Completely compatible file, device, and interprocess I/O Extensive subsystem support FILE SYSTEM One of the important features of our cromix is its file system comprised of hierarchical directories. It's a tree struc- ture of three types of files: data files, lemark of Cromemco, Inc. ark of Bell Telephone Laboratories G directories, and device files. File, device, and interprocess I/O are com- patible among these file types (input and output may be redirected inter- changeably from and to any source or destination). The tree structure allows different directories to be maintained for different users or functions with no chance of conflict. PROTECTED FILES Because of the hierarchical structure of the file system, cromix maintains separate ownership of every file and directory. All files can thus be protected from access by other users of the system. In fact, each file is protected by four separate access privileges in each of the three user categories. TREMENDOUS ADDRESS SPACE, FAST ACCESS The flexible file system and general- ized disk structure of cromix give a disk address space in excess of one gigabyte per volume — file size is limited only by available disk capacity. Cromemco 280 BERNARDO AVE., MOUNTAIN VIEW, CA 94040 • (415) 964-7400 Tomorrow's computers today Speed of access to disk files ha been optimized. Average access speeds far surpass any yet implemented microcomputers. id on roo 'C COMPILER AVAILABLE, T( Cromemco offers a wide range of languages that operate under cromix. These include a high-level command process language and extensive sub system support such as cobol, fortr IV, RATFOR, LISP, and 32K and 16K basics. There is even our highly-acclatme 'C' compiler which allows a prograr mer fingertip access to cromix syste calls, THE STANDARD O-S FOR THE FUTURE The power and breadth of its feature make cromix the standard for the next generation of microcomputer operatir systems. And yet it is available for a surpr low $595. The thing to do is to get all capability working for you now. Get in touch with your Cromemco rep today ne next perating *** all this Circle 470 on inquiry card. In The Queue EWE Volume 7, Number 4 April 1982 Features 32 The Generic Word Processor, A Word-Processing System for All Your Needs by Philip Schrodt / You'll be amazed by this product's versatility. 40 Use Infrared Communication for Remote Control by Steve Garcia / Texas Instruments' SN76832AN Infrared Remote-Control Receiver simplifies the tough job of receiving modulated infrared light. 50 How to Use Color Displays Effectively, A Look at the Elements of Color Vision and Their Implications for Programmers by John Durrett and Judi Trezona / Color is becoming an affordable option for personal computers, but like any new tool, it has special limitations and requirements. 56 A Human-Factors Case Study Based on the IBM Personal Computer by Robert G. Cooper Jr., Paul Thain Marston, John Durrett, and Theron Stimmel / Members of a human-factors evaluation team put the Personal Computer to the test. 108 A Human-Factors Style Guide for Program Design by Henry Simpson / Design considerations that make programs user- friendly. 1 34 The Atari Tutorial, Part 8: Generating Sound with Software by Bob Fraser / The sound capabilities of the Atari 400 and 800 are influenced by the software technique used. 1 58 A Pojrjtpourrl of Ideas, Fifth In a Series by William Barden Jr. / Three inexpensive hardware and software projects for a tone generator, a telephone dialer, and an RS-232C output channel. 1 86 The Input /Output Primer, Part 3: The Parallel and HPIB (IEEE-488) Interfaces by Steve Leibson / An introduction to two common interfaces between computers and other devices. 212 User's Column: The Osborne 1, Zeke's New Friends, and Spelling Revisited by Jerry Pournelle / A seasoned computer user takes a look at new products and updates. 242 Designing the Star User Interface by Dr. David Canfield Smith, Charles Irby, Ralph Kimball, Bill Verplank, and Eric Harslem / The Star User Interface adheres rigorously to a small set of principles designed to make the system seem friendly by simplifying the human -ma chine interface. 284 Designing a Text Editor? The User Comes First by Steven Jong / A system's power is measured in ease of use. 302 Managing Words: What Capabilities Should You Have with a Text Editor? by Craig A. Finseth / The ideal text editor is defined drawing on the experience of many users. 322 A Disk Operating System for FORTH, An In-depth Look at How a DOS Operates by Peter Reece / Develop a DOS for the FORTH language and gain an understanding on how all DOSes operate. 380 MOD III: TRS-80 Model III Features for Your Model I by Joe W. Rocke / Add video line print, selectable cursor, and automatic key repeat to your TRS-80 Model I. 398 Binary-Coded Text, A Text-Compression Method by Dr. Richard Tropper / You can trim text size by 40 percent by encoding common character strings. 439 Career Opportunities In Computing by Jacqueline Johnston / Hobby-level interest in computers can lead to a career tn the computer industry. 447 Converting Apple DOS and Pascal Text Files by John B. Matthews / Now you can exchange information between DOS 3.3 and Pascal Operating Systems. 464 A Simple Multiprocessor Implementation by John Harrington / A simple connection can be the start of a multiprocessing, multitasking system. 472 An Introduction to NSC Tiny BASIC, The Language of the INS8073 by Jim Handy / National Semiconductor's unique version of Tiny BASIC combines the elegance and efficiency of assembly language with the convenience of a high-level language. Reviews 76 The Hewlett-Packard Interface Loop-HPIL by Robert Katz 96 Strawberry Tree's Dual Thermometer Card for the Apple by Dr. William Murray 312 Two Word Processors for North Star by Edgar F. Coudal 371 Selector IV by Micro-Ap, An Information-Management Program by Jack L. Abbott Nucleus 6 Editorial: A Revolution m Your Pocket 20 Letters 102, 1 55, 240 Book Reviews. Software Psychology: Human Factors in Computer and Information Systems; The Mind's I; Handbook of Digital IC Applications 1 04 Product Description: The Epson HX-20, The First Byte-sized Computer 362 Technical Forum: MicroShakespeare 3 414 BYTELINES 4 1 8 BYTE's Bits 419 What's New? 429 Ask BYTE 432, 436 Programming Quickies: A BASIC Program for Home Cryptography; Base Conversion on the TRS-80 Pocket Computer 435 Software Received 482 System Notes: Easy-Entry Program for Radio Shack's Color Computer 489 Clubs and Newsletters 490 Books Received 491 Event Queue 542 Unclassified Ads 542 BOMB, BOMB Results 544 Reader Service • *•••• • • * * • *•*••• • * * • * • ••*•• .**••* • ••*•• • • • • • • ••••• l Page 40 Page 50 Page 56 Page 76 April 1982 © BYTE Publications Inc 3 m Editor in Chief Christopher Morgan Managing Editor Mark Haas Technical Editors Gregg Williams, Senior Editor; Richard S. Shuford; Curtis P. Feigel; George Stewart; Arthur Little; Stanley Wszola; Steve Garcia; Mark Dahmke Philip Lemmons; Allan Lundell. Consulting Editors; Jon Swanson, Drafting Editor Copy Editors Beverly Crania Chief; Faith Hanson; Warren Williamson; Anthony J. Lockwood; Ann Graves; Linda M. Evers; Hilary Selby Polk; Elizabeth Kepner Assistants Faith Ferry; Debe Wheeler; Beverly Jackson Production David R. Anderson, Assoc, Director; Jonathan M. Graves, Creative Consultant; Patrice Scnbner; Damian Henriques;. Jsn Mutter; Linda J. Sweeney; Virginia Reardon; Sherry McCarthy, Chief Typographer; Debi Fredericks; Donna Sweeney; Valerie Horn Advertising Thomas Harvey, Director; Marion Carlson; Rob Hannings; Deborah Porter; Vicki Reynolds; Cathy A. R. Drew; Jacqueline Earnshaw, Reader Service Coordinator; Wai Chiu Li, Advertising/ Production Coordinator Circulation Gregory Spitzfadea Manager; Andrew Jackson, Asst. Manager; Agnes E. Perry; Barbara Varnum; Louise Menegus; Pinky Krulis; Sheila A. Bamford James Bingham, Dealer Sales; Deborah J. Cad well, Asst. Linda Ryan Controller's Office Daniel Rodngues, Controller; Mary E. Fluhr, Acct, & D/P Mgr.; Karen Burgess; Jeanne Cilley; Linda Fluhr; Vicki Bennett Traffic N. Scott Gagnon; Scott Jackson, Kathleen Reckhart Publishers Virginia Londoner; Gordon R. Williamson; John E. Hayes, Associate Publisher; Cheryl A. Hurd; Michele P. Verville, Publisher's Assistants; Officers of McGraw-Hill Publications Com- pany: Paul F. McPherson, President; Executive Vice Presidents: Daniel A. McMillan, III, Gene W. Simpson; Senior Vice President-Editorial: Ralph R. Schulz; Vice Presidents: Kemp Ander- son, Business Systems Development; Harry L. Brawn, Special Markets; Robert B. Doll, Circula- tion; James E. Hackett, Controller; Eric B. Herr, Planning and Development; H. John Sweger, Jr.. Marketing. Officers of the Corporation: Harold W. McGraw Jr., Chairman and Chief Executive Officer; Joseph L. Dionne, President and Chief Operating Officer; Robert N. Landes, Senior Vice President and Secretary; Ralph J. Webb, Treasurer. :ne 2 ra il. an- *- ase ain ter In This Issue As computer technology continues to make inroads into our lives, the man/machine interface assumes greater importance in the total system design. Human-factors engineering, our theme this month, is the discipline concern with the need for friendly computers. Our cover, photographed by Paul Avis, features a new, user-friendly product, the IXO Telecomputing System. For a detailed description of this hand-held terminal see Chris Morgan's editorial To help you make your systems user-friendly, we present "A Huma Factors Style Guide for Program Design" by Henry Simpson and "O signing the Star User Interface" by Dr. David Canfield Smith, Charles Irby, Ralph Kimball, Bill Verpiank and Eric Harslem. In "A Human-Factors Cas< Study Based on the IBM Personal Computer," Robert G. Cooper Jr., Paul Thai Marston, John Durrett, and Theron Stimmel discuss the Personal Compute! from a human-factors perspective. Steve Garcia demonstrates how to use in- frared systems, William Barden Jr. presents a collection of projects for the TRS-80 Color Computer, Gregg Williams treats us to a sneak preview o Epson's new portable computer, and Bob Katz reviews the Hewlett-Packan Interface Loop. BYTE is published monthly by BYTE Publications Inc. 70 Mam St, Peterborough NH 03458, phone {603} 924-9281 , a wholly-owned subsidiary of McGraw-Hill, Inc. Address subscriptions, change of address, USPS Form 3579, and fulfillment questions to BYTE Subscriptions, POB 590, Martinsville NJ 08836. Second class postage paid at Waseca, Minnesota 56093 - USPS Publication No. 528890 (ISSN 0360-5280). Canadian second class registra- tion number 932 J . Subscriptions are S 1 9 for one year, S34 for two years, and S49 for three years in the USA and its possessions. In Canada and Mexico, S2 1 for one year, $38 for two years, S 55 for three years. $43 for one year air delivery to Europe. $35 surface delivery elsewhere. Air delivery to selected areas at additional rates upon re- quest. Single copy price is $2.95 in the USA and its possessions, $3.50 in Canada and Mexico, $4.50 in Europe, and $5.00 elsewhere. Foreign subscriptions and sales should be remitted in United States funds drawn on a US bank. Printed in United States of America. Address all editorial correspondence to the editor at BYTE, POB 372, Hancock NH 03449. Unacceptable manuscripts will be returned if accompanied by sufficient first class postage. Not responsible for lost manuscripts or photos. Opinions expressed by the authors are not necessarily those of BYTE. Entire contents copyright © I 982 by BYTE Publications Inc. All rights reserved. Where necessary, permission is granted by the copyright owner for libraries and others registered with the Copyright Clearance Center [CCCJ to photocopy any article herein for the base fee of $ 1 .00 per copy of the article or item plus 25 cents per page. Payment should be sent directly to the CCC 2 1 Congress St, Salem MA 01 970. Copying done for other than personal or internal reference use without the permission of McGraw-Hill is prohibited. Requests for special permission or bulk orders should be addressed to the publisher. BYTE® is available in microform from University Microfilms International, 300 N Zeeb Rd, Dept PR, Ann Arbor Ml 48106 USA or 18 Bedford Row, Dept PR, London WCIR 4EJ England. Office hours: Mon-Thur 8:30 AM - 4:30 PM, Friday 8:30 AM - Noon, Eastern Time April 1982 © BYTE Publications Inc ". . .stands well above other S-100 graphics dis- plays in its price and per- formance range." BYTE, Product Review . better monochromatic . display . ELECTRONIC DESIGN, 1981 Technology Forecast MICKQ\NGELO HIGH RESOLUTION GRAPHICS SINGLE BOARD COMPUTER 512x480 resolution black and white and vivid color displays RS- 170 com- posite or direct drive output Local or external sync generation 4MhzZ80 microprocessor 60 hertz real- time clock 8 level interrupt tie-in IEEE SI 00 bus compatible Screenware™ Pak I A 4K byte operating system resident in PROM on MicroAngelo™. Pak I emulates an 85 character by 40 line graphics terminal and provides over 40 graphics commands. Provisions exist for user defined character sets and directly callable user extensions to Screenware™ Pak I. Screenware™ Pak II An optional software superset of Pak I which adds circle generation, polygon flood, program- mable split screen for separate graphics and ter- minal I/O, relative coordinates, faster vector and character plotting, a macro facility, full UCSD Pascal compatibility, and more. light pen interface Time multi- plexed refresh 4K resident Screenware™ Pak I operating system 32KRAM isolated from host address space High speed communications over parallel bus ports And now... COLOR!! The new MicroAngelo™ Palette board treats from 2 to 8 MicroAngelos as "bit planes" at a full 512 x 480 resolution. Up to 256 colors may be chosen from 16.8 million through the program- mable color lookup table. Overlays, bit plane precedence, fade-in, fade-out, gray levels, blink- ing bit plane, and a highly visual color editor are standard. Ask about our multibus and RS-232 versions. Circle 363 on inquiry card. 12310 Pinecrest Road • Reston, VA 22091 • (703) 476-6100 • TWX: 710-833-0684 Circle 146 on inquiry card. / s fOOt-note, n. 7. a note or comment at the end of a page, referring to a specific part of the text on the page. 2. an essential program for the serious WordStar user. FOOTNOTE™ brings full foot- noting capabilities to WordStar™. FOOTNOTE automatically num- bers both footnote calls and foot- notes, and formats the text, placing footnotes on the bottom of the correct page. At the user's option, the footnotes can also be removed from the text file to a separate note file. Footnotes can be entered singly or in groups, in the middle or at the end of paragraphs, or in a completely separate note file. After running FOOTNOTE the user can re-edit the text, add or delete notes, and run FOOTNOTE again to re-number and re-format the WordStar file. The price is $125., and includes PAIR, a companion program that checks that printer commands to underline or set in BOLDFACE, are properly terminated. FOOT- NOTE and PAIR require CP/M™, WordStar, 48K RAM and a Z80 or 8080/85 computer. SOFTl4^RE SOFTWARE DIGITAL /MARKETING DIGML/VMRKETING M 2670 Cherry Lane • Walnut Creek • CA 94596 (415) 938-2880 Tefex #17-1852 (DIGMKTG WNCK) PRO JEM FOOTNOTE and PAIR trademarks ol PRO/TFM Software Inc WordStar trademark of Micropro Infl CP/M trademark of Digital Research ^ Editorial A Revolution in Your Pocket by Chris Morgan, Editor in Chief Imagine a terminal that costs about $500 and can: • access the Source, CompuServe, Dow Jones, or other remote database or computer services • automatically handle the protocols to access these services so that you need only enter your password to be online • have a full ASCII character set • have a built-in modem with autodialer and full- and half-duplex capability • be able to emulate other terminals • have an uninterruptible power supply • fit in your pocket • operate from a battery Sounds amazing, doesn't it? Yet it's not fantasy; the product does exist. It's called the IXO Telecomputing System (hereafter referred to as the Telecom- puter), and it's featured on our cover this month. Photo 1: The IXO Telecomputing System. It's a complete pocket terminal with built-in modem and autodialer that will sell for about $500. The phone number displayed is IXO's Access Center. 6 April 1982 © BYTE Publications Inc You Get More Out of Percom Disk Systems. At Percom, our business is making disk storage systems for microcomputers — something we've been doing right, since 1977. From the design of rock-solid drive controller circuitry to quality controls that include 100% life testing of every drive ship- ped, you can expect to get more out of Percom Disk Systems. And Percom provides you with com- prehensive after-sales service from our wholly owned, fully independent customer service center. WINCHESTER 10-MEGABYTE DISK STORAGE || SYSTEMS Enormous storage capacity plus high speed. Percom 5 1 /4 inch hard disk systems are 40 times faster than single-density floppy mini-disks, 20 times faster than double- density units. Systems include a smart, four-drive controller featuring state-of-the-art data encoding and separation, adaptable industry-standard disk interfacing. Plug-in-compatible version for TRS-80* Model III computer, available now. Watch for IBM PC, Apple II, Atari, and H/Z-89 versions. Prices start at under $3000, including software. Also ^^available with 5 or 15-Mbyte drives. Coming soon! Ten megabyte removable- disk cartridge drive. FLOPPY MINI-DISK STORAGE SYSTEMS 40 or 80-track drives, single or dual-head, flippy or non- flippy— all double-density rated. Available in 1, 2 and 3- drive add-on units, 1 and 2-drive internal units, with full docu- mentation and software support. Add-on drives from $399, complete systems from $459.95. To learn more about quality Percom disk storage systems, mail the coupon today. Or, call toll-free 1-800-527-1222. Ask for booklet "D". YES ...I'd like to know more about Percom disk systems. Please rush me booklet "0" Send to: PERCOM DATA COMPANY, INC. Dept BD1 11220 Pagemill Road, Dallas TX 75243 street city state zip phone number I'm interested in floppy disk storage for my... TRS-80 nMdl III LJMitl I H IBM PC □ H/Z-89 [JH-8 []AIM/KIM/SYM DSystem-SO Ym interested in hard disk storage for my... DIBM PC riTRS-SOMdl III [ lApple II QAtari □ H/Z-89 Ojher computer? „___ (□floppy disk or [J hard disk?) The Drive People 11220 Pagemill Road • Dallas TX * 75243 • (214) 340-7081 PRICES AND SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE, "TRS-80 is a trademark of Tandy Radio Shack Corporation which has no relationship 'to Percom Data Company, inc G 1981 Percom Data Company, Inc PROFESSIONAL PASCAL l'ilS€«ll/ 4o0 SYMBOLIC DEBUGGER This fourth generation version of our reliable, Z-80 native code compiler adds the two features professionals ask for: ♦ SWAT™— an interactive symbolic Pascal debugger that allows easy error detection. ♦ Overlays— that allow larger programs to run in limited memory. A compiler for Professional programmers Pascal/Z is a true Pascal. It closely follows the Jensen and Wirth standard with a minimum of extensions designed to aid the serious program developer in producing extremely compact, bug-free code that runs FAST. Pascal/Z generates Z-80 native code that is ROMable and Re-entrant. Permits separate compilation, direct file access, external routines and includes a relocating macro assembler and Microsoft compatible linker. And code written for Pascal/Z is fully compatible with I*PAS 8000, our new native code Pascal compiler for Z-8000, to guarantee graceful migration to 16 bit operation. Get "The FACTS about Pascal" ^ Confused about which Pascal to buy? Ife^tateto^ Pseudo-code . . . Native code . . . M, MT or fc ^^ Z? Compare the unbiased benchmarks % ,^^ in our new booklet. Don't buy a Pascal \- r compiler until you've read it. •*<■ ^ ™ii# Call us for a free copy: 800-847-2088 (outside NYS) or 607-257-0190 And ask your local full-service computer dealer about our Pascal/Z demo package. V^ Ithaca Intersystems Inc. Micros for bigger ideas. Ithaca Intersystems Inc. 1650 Hanshaw Rd • Ithaca, NY 14850 • TWX 510 255-4346 U.K. Distributor: Ithaca Intersystems (U.K.)Ltd. Coleridge Road London N8 8ED Phone: 01-341 2447 Telex: 299568 Editorial. I first saw the Telecomputer nearly a year and a half ago when I visited its inventors, husband-and-wife team Bob and Holly Doyle, at their Cambridge-based com- pany, Macrocosmos. The Doyles conceived of a portable but powerful computer terminal, and with the aid of elec- tronic-design wizards Michael Suchoff and Andy Barber, they built a limited number of prototypes. The Doyles later joined forces with former Mattel Electronics presi- dent Jeff Rochlis to form IXO Inc., the company that markets the Telecomputer. I received one of the proto- types for testing last year and I've been using it ever since. I'm still amazed at the features packed into its exceedingly small package. This month's theme is human-factors engineering, and the IXO Telecomputer is an excellent example of a ter- minal designed with the user in mind. The Telecomputer, which will be generally available this summer, has a lot to offer in addition to its human factoring. It has, for in- stance, a sophisticated security-protection system and in- novative, compact circuitry. I'll touch on these topics, but my main objective here is to discuss the implications of IXO's design philosophy. Photo 2: The Telecomputer is powered by a built-in Polaroid Polapulse flat battery. Photo 3: The FCC-registered Telecomputer is designed to at- tach directly to a phone using a standard modular jack. When in use, the terminal draws all of its power from the phone line. Circle 219 on inquiry card. Circle 220 on inquiry card. h computer system so advanced, the technology you 11 need later is already here. And waiting for your call. 3QQ-347-2D33 In New York State (607) 257-0190 Ithaca Intersystems Inc. 1650HanshawRd. RO. Box 91 Ithaca, New York 14850 TWX 510 255 4346 Circle 160 on Inquiry card. Authorized Commodore service center Repair of the compfete line of Commodore products In a hurry? Check our modular exchange program Disc Drive commodore Printer HARDWARE: SOFTWARE: CBM 8032 Computer, ozz $299 80 Column $1095 Wordcraft 80 299 CBM 8050 Disk Drive 1340 Tax Preparation System 380 CBM 4032 Computer, IRMA 380 40 Column 995 Dow Jones Portfolio CBM 4040 Disk Drive 995 Management System 1 15 CBM 4022 Printer 649 Personal Tax 55 CBM VIC 20 Computer 263 Pascal 229 CBM VS 100 Cassette 68 Assembler Development PET to IEEE Cable 33 Package 77 IEEE to IEEE Cable 39 Wordpro 4+ 329 BASF Diskette, Box of 1 30 Order TOLL FREE 1+800-527-3135 1 AM to 4 PM CDT Monday through Friday Texas residents call 1 +2 1 4-66 1 - 1 370 Vf W MASTER CHARGE, MONEY ORDERS, AND C.O.D. "Certified Check" accepted. Units in stock shipped within 24 hours, FO.B, Dallas, Texas. All equipment shipped with manufacturer's warranty. Residents of Texas, Louisiana, Oklahoma City and Tulsa, Oklahoma must add applicable taxes. Eclectic shortly will be announcing products that are designed to work with CBM systems. ? . ROMIO: two RS232 ports - three parallel ports - 26K EPROM memory-managed alternate character set software controlled -EDOS (extended DOS). 2. Terminal program (options with ROMIO) 3. EPROM programmer 4. Front-end processor 5. Additional firmware to be announced r sure to write the address below for more information; dealer inquiries welcome. P.O. Box 1 166 • 16260 Midway Road Addison, Texas 75001 • (214) 661-1370 Editorial , Photo 4: Four peripherals for the Tele computer (clockwise from upper left): an acoustic interface (not the same as an acoustic coupler because the modem circuitry is already con- tained inside the terminal); the R5-232C interface, a video inter- face; and a 20-column printer. The Telecomputer marks the beginning of a whole new "genus" of computer products: no-compromise portable computers that are truly user-friendly. Let's take a closer look at its features. The Telecomputer comes in a small plastic case con- taining densely packed CMOS circuitry and a Polaroid Polapulse flat battery to drive it (see photo 2). The heart of the design is an NEC 4-bit microprocessor with IK bytes of CMOS RAM (random access read/write mem- ory). The keyboard, which is slightly too small for extended typing sessions, contains several unusual keys to help the naive user (and sometimes the not-so-naive user). These include the YES, NO, DON'T KNOW, HELP, and PHONE keys. They are brightly colored to attract your attention. The HOLD, SLOW, FAST, REPT, GO BACK, CLR CHAR, and CLR ENTR keys are dark blue. The usual BREAK, ESCAPE, and CONTROL keys are gray. The blue and gray colors tend to keep the more complex keys in the background in order not to distract or in- timidate the beginner. A Session with the Telecomputer After you remove the Telecomputer from its box and turn it on, you then connect it to your telephone line by plugging your telephone cord's modular jack into the female socket at the back of the terminal (see photo 3). At this point the Telecomputer begins to draw all of its power from the phone line while the phone is "off hook," i.e., while the phone is in use (a clever arrangement by the machine's designers). Since the phone companies re- quire all phone devices to draw 20 milliamps to prove that the devices are using the lines anyway, this becomes a perfect source of power for CMOS circuitry! In fact, telephone devices are allowed to draw 5 microamps while "on hook," so it becomes theoretically possible to trickle- charge a battery. 10 April 1982 © BYTE Publications Inc Circle 380 on inquiry card. \ ' — «*-. K L J ~*~z *"■ ■ ^M •.v * %^--=- "'"""' *w$ ^^^ ' M ^j..,- r . -.-: Every Apple Is Created Equal. But It Doesn't Have To Stay That Way. An Apple™ is really something. Hut from now on, it's going to be something much more. How come? Simple. We're introducing three revolutionary new data communica- tion packages, called Transend™, designed especially to make your Apple II™ rise above all others. Our Transend data communica- tions software provides access to in- formation utilities; complete file transmission of charts, VisiCale™ reports, and entire programs; as well versions. You can begin economically with the simplest form, Transend I, an intelligent terminal/ file transfer system. As your needs increase, you can move up to two other Transend packages, without worrying about retraining or repurchasing. Transend 2 gives any Apple 1 1 intelligent ter- minal capabilities, plus file transfer with complete error detection and automatic retransmission for de- manding business applications. Transend 3 incorporates electronic mail— with password se-curity, text editing, mailbox with mailstop, unat tended scheduling and receiving, automatic redialing, and much more, IfiSgjSS'j SStTi ?he Transformation People Transend 's support of most popu- lar Apple II "add-in" cards and modems lets you upgrade your Apple without hassle or unnecessary exoense. And vou'll immediately cut expense. And you u immediately cue operating costs by as much as 30% with simple, easy-to-use menus, data compression and 1200-baud modem support. Nobody on the personal computer scene today is offering the speed, flex- ibility, and reliability of Transend in a single upgradable software system. Don't miss this chance to uplift your Apple II. Contact us or your dealer for all the delicious details. SSM Microcomputer Products, Inc. 2190 Paragon Drive, San Jose, CA 95131, (408) 946-7400, Telex: 17117 TWX: 910-338-2077. Apple and Apple 1 1 art Computer, Inc. VisiCal sonul Software, Inc. Ar mark of SSM Microcon Jmw US* Larii re •mi fcij i r • ire iWi l/OU irAni ale. Introducing the first totally compatible Floppy Disk Drive. Rana Systems has designed a totally compatible disk drive for Apple, that's better than Apple's. A high density, high capacity disk drive and controller that offers a myriad of features Apple never thought of. Unique advan- tages that get the maximum efficiency out of your existing Apple IP hardware and software. At Rana, we knew you wanted more storage, so we went right to the core of the problem. Even our most economical model is designed to give you 15% more storage capac- ity than Apple's. Our top-of-the-line unit gives Apple II is a registered trademark of Apple Computer Inc. you 4 times the capacity of Apple's comparable unit Even our design is tar more dramatic than theirs. With lines that actually complement the sleek Apple II computer. We're a step ahead of Apple because we have a faster step. Holding more information is even more valuable when you can get it faster. The Rana System track positioning mechanism is engineered to access three to four times faster track to track, with greater accuracy than Apple's. Our disk drive offers safeguards like a stall provision to protect spin motor burnout, an advanced write protect feature that keeps your information where you put it and an energy saving device that "powers down" when your disk drive is taking a break. We even took a bite out of Apple's price. Our most popular model is 25% more economical per byte than Apple's, providing you with maximum performance, superior cost efficiency, and totally compatible styling. It also comes with a free diskette containing all the optional software and supports you'll need to enhance the capacity and performance. And it's all backed up with an efficient service support system, and a full 90 day warranty. The Rana System Floppy Disk Drive. Just plug it into your Apple and all those delicious extra bytes will be yours. RanaSystems. Circle 353 on inquiry card. 206Z0 South Leapwood Avenue. Carson, CA 90746 213-538-2353. For dealer information call toll free: t-800-421 -2.207. In California only call: 1-800-262-1221 .Source Number TCT-654. se our booth at the West Coast Computer Faire Show. CP/M® disk w Itti / (nam LANGUAGES 3-/H5 Basic Microsoft Basic Compiler Microsoft C-Basic CB80 COBOL 80 C Compiler Forth Fortran Fortran 80 muLISP Pascal/M Pascal Z P/L 1^80 RATFOR Fortran S-Basic Dig. Research Dig. Research Microsoft Supersoft Supersoft Supersoft Microsoft Microsoft Sorcim Ith. Intersys. Dig. Research Supersoft RATFOR Micro AP $329/- $110/20 $437/37 $574/— Tiny Pascal Supersoft 5169/45 $209/30 $375/- $169/— $345/30 $349/30 S469/40 $85/- $289/35 S269/25 $79/25 ACT I Despoof Diagnostic I Macro 80 MAC QSORT SID ZSID ASSEMBLERS/UTILITIES Sorcim Dig. Research Supersoft Microsoft Dig. Research Struc. Sys. Dig. Research Dig, Research $152/25 $50/- $84/20 $162/- $70/15 $90/15 WORD/TEXT PROCESSING Edit 80 Letteright MagicWand Mail Merge NAD Spellguard SpellStar Textwriter III Word Star TRS-80®/Mod. Z~89 Z-90 Microsoft Struc. Sys. Peachtree MicroPro Struc. Sys. ISA MicroPro Dig. Research $907- $156/- $289/45 $108/25 $907- $225/25 $175/40 $100/10 Organic Softwr $110/ — MicroPro $289/60 CP/M® ll(P&T) $169/- $140/- $140/- APRIL B2 Specify format. Most disk formats available. DATA BASE MANAGEMENT dBASE II Ashton-Tate $594/50 Series 20-1 Condor $249/50 Series 20-2 Condor $509/50 Data Star MicroPro $245/60 FMS^80-1 Systems Plus Call FMS-80-2 Systems Plus Call INCOME TAX MICRO TAX Lev. 1 (Indvl.) $225/- Lev.2{Proi) Call Lev. 3 (Partner) Call Lev. 2 & 3 Calf State Tax Call ACCOUNTING TCS G/LorA/P or A/R or Payroll $75/25 All four $250/99 ACCOUNTING PLUS™ G/L $439/67 A/P $375/67 A/R $375/67 Payroll $375/67 Inventory $375/67 Safes Order $375/67 Point of Sale $375/67 Purch. Order $375/67 PEACHTREE-SERIES5 G/L $437/40 A/P $437/40 A/R $437/40 Payroll $319/40 Inventory $437/40 Sales Invoice $437/40 ANALYSIS/MODELING CalcStar MicroPro $229/45 Milestone Organic Softwr $269/— muMATH/muSIMPMicrosoft $225/— Supercalc Sorcim $259/ — Worksheet Soho Group $185/— «289J WORD STAR REDUCED software . . . with lots of technical support CALICO [213)475*104 M *-» — I **.* W TQ 0RDER CALL T0LLFREE (800) 854-2003. ext 75 (800)522-1500, ext 75 in Calif. CP/M - 86 Call us at (213) 475-8104 for available software. APPLE II® 10 J. Datadex Easy Writer (40 col) Easy Mailer (40 col) Forth Pro. Easy Mailer Pro. Easy Writer MICROPRO Mail Merge Super Sort I Word Star Word Star + Mail Merge MICROSOFT A.L.O.S. Basic Compiler Fortran-80 16K RAM Card Z^O Soft Card $258 $88 $61 $123 $149 $225 $97 $159 $105 $320 $175 $149 $295 PEACHTREE G/L A/R A/P Payroll Inventory Mail. List HOWARD SOFTWARE Income Tax VISICORP Desktop Plan II VisiCalc VisiDex VisiFile VisiPlot VisiFerm VisiTrend/VisiPlot $219 $219 $219 $219 $219 $219 Call $199 $199 $199 $199 $162 $149 $243 MASTER CHARGE/VISA CALICO 1746' ? Westwood Blvd. Los Angeles. CA 90024 (213)475*104 Add $3.50/item for shipping, handling. Overseas add $10. California residents add 6% sales tax. Allow time for checks to clear. Prices subject to change without notice. All items subject to availability. ®Registered trademark. Editorial 14 April 1982 © BYTE Publications Inc Circle 71 on inquiry card. After you hit the ON switch, the unit's liquid-crystal one-line display begins presenting a series of questions in menu format. The first query you see is "ACCESS CENTER?" The best way to learn about the unit is to dial the Access Center, a remote computer resource center maintained by IXO to service Telecomputer customers. You simply type in the telephone number and the unit automatically dials it. The Telecomputer senses whether your phone line is Touch-Tone or rotary-dial and sends out the appropriate signals. Once online, you can experi- ment with the simulated services offered by the Access Center, including a checkbook-balancing program, a travel-agency simulation that demonstrates booking airline flights, a television guide database to help you find TV show times, and so on. The main purpose of this exer- cise is to illustrate the advantages of services using plain English dialogue back and forth between the user and the computer. In time, real versions of such computer ser- vices will be available. When connected to the Access Center, you can always press the HELP key if you get stuck and get a more detailed explanation of what to do next. You can also press the DON'T KNOW key if in doubt as to the correct reply to the computer's questions. (If only the existing databases had these features!) The Telecomputer's designers have been trying for some time to convince the people who run the databases to adopt these user-friendly approaches. Let's hope they do. The most important feature of the Access Center is that it can download protocols for The Source, CompuServe, and Dow Jones into your terminal's RAM. (These were the three services available at the time I evaluated the unit; more will undoubtedly be added later.) Download- ing protocols takes about 30 seconds and needs to be done only once because the information is permanently stored in the terminal as long as the battery holds up, which is at least a year — longer if you're "off-hook" fre- quently. Once you're connected, the Access Center asks you to type in a password that you must use in all future dealings with the Center and also asks for your name. I was surprised the second time I called the center to find that it greeted me with "HELLO CHRIS. PASS- WORD?" It's hard to convey the excitement of seeing a message like this on a miniature terminal connected directly to your phone line. Future shock, indeed. The next time I used the terminal, I decided to get on the Dow Jones database and analyze some stocks. I powered up the Telecomputer, entered my password, and it immediately asked "DOW JONES?" The down- loading had worked! Out of curiosity I pressed NO and the terminal stepped to the next item: "THE SOURCE?" NO again. "COMPUSERVE?" NO. "MANUAL AC- CESS?" (The latter mode lets you dial any general data- base or computer by entering a telephone number.) I cycled around to "DOW JONES?" again and pressed YES. (Incidentally, you can type "yes", "Y", hit the YES key, or the ENTER key to tell the terminal yes. The designers have obviously thought of every possibility to Circle 333 on inquiry card. | HOW TO USE YOUR EPSON WITHOUT WASTING COMPUTER Your computer is capable of sending data at thousands of characters per second but the Epson can only print 80 characters per second. This means your computer is forced to wait for the printer to finish one line before it can send the next, A waste of valuable time. THE NEW MICROBUFFER™ ACCEPTS DATA AS FAST AS YOUR COMPUTER CAN SEND IT. Microbuffer stores the data in its own memory buffer and then takes control of the printer. This frees your computer for more productive functions. PARALLEL OR SERIAL Microbuffer model MBP-16K is a Centronics-compatible parallel interface with 16,384 bytes of on-board RAM for data buffering. The MBS-8K is a full-featured RS-232C serial interface with both hardware and software (X-On/X-Off) handshaking, baud rates from 300 to 19,000 and an 8,192 byte RAM buffer. SIMPLY PLUG IT IN. Either model fits the existing auxiliary interface connector inside the Epson MX-80, MX-80 F/T or MX-100 without modification, and is compatible with standard Epson cables and printer control software, including GRAFTRAX-80. JUST $159.00* When you think how much time Microbuffer will save, can you afford not to have one? Call us for your nearest dealer. L PRACTICAL PERIPHERALS. INC. 31245 LA BAYA DRIVE, WESTLAKE VILLAGE, CA 91362 • (213) 991-i Editorial- James Martin, data-processing and futures expert, offers the following predictions about the role of the pocket terminal ten years in the future. The following excerpt is from his book, Telematic Society: A Challenge for Tomorrow (Prentice-Hall, 1981). Pocket terminals mushroom in sales and drop in cost as fast as pocket calculators did a decade earlier. Most people who carried a pocket calculator now have ; a pocket terminal The pocket terminal however, has | an almost endless range of applications. It can access many computers and data banks via the public data networks. The pocket terminal becomes a consumer product (as opposed to a product for businesspeople) on sale at supermarkets, with human factoring that is simple and often amusing. The public regard it as a companion which enables them to find good restau- rants, display jokes on any subject, book airline and theatre seats, contact medical programs, check what their stockbroker computer has to say, send messages, and check their electronic mailbox. Public data networks are ubiquitous and cheap, and accessible from every telephone. Their cost is indepen- dent of distance within most countries. ft TS- 1 Your Total Solution in a Smarter Terminal . . . TS-1 gives you the best of everything. From ergonomics to emulations, from upgradable performance to user programmable features. Never has one terminal had so much to offer to such a wide variety of users . . . Therefore your Total Solution .. . Through user- selectable or optional changes the TS-1 Emulates Almost Any Terminal. The result is remarkable cost*effictency with unbeatable performance, and obsolescence*proof design for today and tomorrow . . . Just some unbeatable features.,. • Built-in Bell 2X2 compatible modem/auto dialer (optional) • 16K memory with horizontal scrolling to 256 columns (optional) • Visual attributes not stored on screen — ihics with 100 characters • 28 non-volatile user- programmable function keys ** ft set up eliminates DIP itches . .jt 10 compatible graphics (optional) . Faleo DATA PRODUCTS 1286 Lawrence Station Rd. Sunnyvale, CA94086 (408)745-7123 Telex: 172494 keep naive users from getting stuck.) You've probably gone through the usual tedium of identifying your terminal, hitting carriage returns, and going through all the usual make-work dialogue required to get onto databases. The Telecomputer eliminates all that. Once the Access Center downloads its protocols to your terminal, your terminal automatically completes the dialogue with, say, Dow Jones. You need only enter your password and you're instantly online. It takes only a cou- ple of seconds. If you regularly access several databases or electronic mail services, you'll appreciate not having to memorize a lot of annoying protocols. This sort of elegant engineering will help popularize computers. Another useful feature is the pair of speed-control keys, labeled SLOW and FAST, that control the speed at which text scrolls across the display by sending XON and XOFF control characters to the remote computer. Every time you press one of the keys the display incrementally slows down or speeds up. You can slow the display down to transcribe messages or speed it up to quickly scan through material. There's little more to add about the operation of the Telecomputer — it's that simple. The built-in autodialer remembers your local Tymnet and Telenet numbers after you enter them once. It even shuts itself off if not used for eight minutes, first giving you an audible warning. The machine is truly "goof-proof." Peripherals for the Telecomputer (see photo 4), includ- ing an acoustic interface (not the same as an acoustic coupler because the modem circuitry is already contained inside the Telecomputer — therefore the price is lower); a 20-column thermal dot-matrix printer made by Olivetti; an RS-232C interface; and a video interface designed for use with both TV sets and video monitors, will be avail- able by July. Design Philosophy It's no surprise that the Telecomputer takes a human- factors approach. Its designers come from strong back- grounds in consumer electronics. Bob and Holly Doyle have invented more than a dozen computer toys, includ- ing Parker Brothers' best-selling Merlin and Stop Thief. While at Mattel Electronics, Jeff Rochlis supervised the production of the Intellivision personal computer and hand-held games such as Brain Baffler (to which the Tele- computer bears a coincidental resemblance). Rochlis's four design goals were to make the Telecomputer cheap (it will sell for approximately $500 to $550); portable; easy to use (meaning both ease of access to databases and ease of use via plain English dialogues); and secure. That last point deserves a volume in itself. Someone once said that today's electronic mail services are more like "postcard" services because the security measures are so lax that any half-competent programmer can crack them. The Telecomputer's three-way security keying sys- tem goes a long way to correcting this situation. The user 16 April 1982 © BYTE Publications Inc Circle 177 on inquiry card. PCWSL API § pa^SffS^SSSSS. rom THIS AD MARKED THE BEGINNING OF A NEW ERA IN MICROCOMPUTER PROGRAMMING It announced PEARL" PEARL ushered in the era where programmers could free themselves boring, routine and repetitive tasks. Because PEARL handles 60-70% of programming details, which permits programmers to spend their time more creatively, and more productively. But that was two years ago. Today, there's Personal PEARL - to be introduced at the West Coast Computer Fair. And it goes a giant step further. Personal PEARL makes the capabilities of the computer available to virtually anyone. For its $295 price, even people without technical backgrounds can use it to visually create their own applications and reports on any computer. So the ad you're reading now is announcing an even more important breakthrough in computer and personal productivity. Just think about the RELATIONAL SYSTEMS INTERNATIONAL possibilities. 1 hen Contact OUr rq Box 12892/Salem, Oregon 97309/(503) 363-8929 ersonal PEARL Product Manager. B Circle 355 on inquiry card. CPU International is the former name of Relational Systems International. PEARL (Producing Error-Free Automatic Rapid Logic) Send today for our NEW full-color 56-page catalog with continuous checks, statements, invoices, stationery, envelopes, supplies and accessories. We will also send our FORMS SELECTOR GUIDE, to help you find the right forms for your software. • Quality products at low prices • Available in small quantities • Fast Service • Money-Back Guarantee • Convenient TOLL-FREE ordering Fast Service by mail or. . .PHONE TOLL FREE 1 + 800-225-9550 Mass. residents 1+800-922-8560 8:30 a.m. to 5:00 p.m. Eastern Time Monday — Friday Please rush a new computer forms catalog to: CITY, STATE and ZIP Hardware and Software being used. I S N^ CODE 22460J I Computer Forms I 78 Mollis Street, Groton, Massachusetts 01471 A division of New England Business Service, Inc. Editorial. has a password, the terminal has a built-in password (unknown to the user), and the host computer has a pass- word. (This is the proposed standard. Presently, only the IXO Access Center computer adheres to it.) The host computer combines its password with both the user's password and the terminal password in complex, ran- domized ways to make it virtually impossible for some- one else to emulate your terminal with another terminal or computer, even if he knows your password. It's an ad- mirable approach to securing data. I hope manufacturers will pay serious attention to it. The Telegraphic Age Rochlis likes to compare today's computer age to the telegraphic age of the nineteenth century. In many ways, he says, the technique of talking to computers is still in its "telegraphic" stage. Back when the telegraph was the chief means for long-distance communication, telegraph operators were required as intermediaries for all trans- actions. Unfortunately, they "spoke" a different language than their clients: Morse code. Today, most of the public at large do not know how to operate computer terminals and must rely on computer operators. The latter are in ef- fect the most expensive 'peripherals" of all. To bring computing power to the people, we must supply them with cheap and easy-to-use computers and terminals. There is a trend this year toward the development of briefcase-sized computers and terminals. (See the report about Epson's new HX-20 portable computer on page 104. ) And that's just the beginning: watch for a series of new, small computers from both America and Japan. But size and cost alone will not guarantee the success of these machines with the general public. Human engineering has to be our paramount concern in the personal-computing field; the IXO terminal is a major step in this direction. Piracy Addendum Many people have asked me to comment on the issues of software piracy raised in Jerry Pournelle's January col- umn. (See "User's Column: Operating Systems, Lan- guages, Statistics, Pirates, and the Lone Wolf," January 1982 BYTE, page 132.) My only comment is that, while I sympathize with many of the opinions expressed by Jerry's "mad friend" Mac Lean, my overall attitude toward copying software has not changed since I spoke out in the May 1981 editorial. Nevertheless, I think it's important to air opposing viewpoints in BYTE. The debate is healthy and being overly dogmatic serves no useful purpose. I'd like to hear more from readers about this issue. ■ 18 April 1982 © BYTE Publications Inc Circle 293 on inquiry card. Circle 285 on inquiry card. An Apple II®, a printer, a video screen, a modem, a disk drive, The CPS Multifunction card and cables are all you need to connect almost any printer, mo- dem, or terminal to your Apple II®. It's really three cards in one. It provides the capabilities of a serial interface, parallel output interface, and real-time clock/calendar. It saves you money, power, and slots. The CPS Multifunction is compatible with DOS, CPM, PASCAL, and BASIC. Suggested retail price $239, including software. Cables $24.95 each. The RAMPLUS+ card allows you to expand the available memory of your Apple II® to 80K. RAMPLUS+ has two 16K banks of RAM. The card is supplied with 16K of installed RAM, with an additional 16K of plug-in RAM available. It is compatible with DOS, CPM, PASCAL, and BASIC, also. Suggested retail price $ 189. Additional 16K RAM $24.95. Letters The Missing LINC I keep seeing the "personal computer era" referred to as having begun in the mid-1970s, as if it required the microchip to make it possible to design hardware and software for a single-user computer. But there are important antecedents to this, dating back twenty years, and they were not hand-held calculators so much as proper computers with analog interfaces and mass storage — namely, lab com- puters. In 1962, at MIT's Lincoln Labs, Wesley Clark and Charles Molnar designed the LINC (Laboratory INstrument Com- puter), to be used in a research lab in a manner analogous to an oscilloscope. It wasn't merely its display and analog-to- digital converters (hence joysticks and Spacewar) which made it unique: its soft- ware was designed to enable the scientist- user to program without a professional programming staff. Much of the design rationale was process-control oriented (hence interrupts) so that online data analysis could be performed during an ex- periment, allowing modification to the ex- perimental protocol. But having such a friendly computer in the room, shared only with the other users of the same lab, created the atmosphere of "personal com- puting" a decade before mass-market economics extended it. The first 24 LINCs (with their small memories and dual small-reel magnetic tapes — so-called LINCtapes — which were the forerunners of the floppies) were built under a government research grant and distributed around the country in 1963 to various physics, chemistry, and life sciences labs (they were especially impor- tant in my own field of neurobiology). With the plans in the public domain, several computer manufacturers began selling them (Digital Equipment Corpora- tion's version cost $54,000 — and in 1966 dollars, at that) and improving on the design (DEC's LINC-8 and PDP-12 were the major extensions). In essence, thousands of users experienced the per- sonal computer revolution in the 1960s and helped shape its present philosophy. It is curious how this heritage has been forgotten in the great expansion. One con- sequence is an excessive amount of rein- venting the wheel. The interactive soft- ware packages developed by LINC users (especially at Washington University and the University of Wisconsin) were ex- cellent— I have yet to see a statistics-and- plotting package for microcomputers which equals LINDSY for the LINC, and the LINC s text editor and operating sys- tem (LAP) puts CP/M to shame. And — another forerunner of the present micro- computer situation— the really good general-purpose software came from small groups, not manufacturers. Most people tend to compare new microcomputer software to fancier main- frame versions, but it is often more ap- propriate to compare it to the lab com- puter antecedents, which shared a similar philosophy. It is the design philosophy for microcomputers that so sets them apart from the staffed mini- and main-frame computers, and it is that single-user-as- master philosophy that was so extensively developed by the LINC users. William H. Calvin, Ph.D. Associate Professor of Neurophysiology Department of Neurological Surgery RI-20 University of Washington Seattle, WA 98195 Computer Scrabble* We were pleased to see an article dis- cussing the feasibility of a computer op- ponent for Selchow & Righter's popular Scrabble word game (see "Computer Scrabble," December 1981 BYTE, page 320). Others who are intrigued by this concept will appreciate knowing that the state of the art in microcomputer Scrabble has made a great leap forward. It is far beyond the boundaries that Mr. Roehrig tells us will not be broken by anything less than a new, superior generation of micro- computers. "Monty plays the Scrabble Brand Crossword Game" (a computer-opponent program available on disk for the Apple II and TRS-80 Models I and III from Ritam Corporation for $39.95) demonstrates both speed and ability, within the con- straints of today's microcomputers. Monty spends an average of only 4Vz minutes per move at the highest skill level, and yet it uses an extensive word list (over 50,000), based in part on the Official Scrabble Players Dictionary . As for memory, the program requires no more than 48K bytes for Apple and 32K bytes for TRS-80 versions, much of which is devoted to machine-language graphics, music, and other user-interface requirements. The dictionary is accessed from disk and is stored in an average of only two bytes per word (with an average length of 6 or 7 letters) by use of advanced compression techniques. In addition, Monty is capable of challenging other players' words, based on linguistic anal- ysis, without accessing the disk. To give Mr. Roehrig's efforts due credit, the "game's complexities" do offer a challenge I It took us several major design breakthroughs, over four man- years of programming (for three different computers), and a lot of determination to develop "Monty plays Scrabble" without conceding to "certain constraints" on word length, search, and placement. Although his conclusion that "im- proved computerized Scrabble will re- quire a faster host computer with more memory capacity" has been disproved by example, we thank Mr. Roehrig for his ar- ticle. It makes our endeavor seem quite worthwhile when we learn that we've achieved the impossible! By the way, Mr. Roehrig neglected to properly acknowledge that Scrabble is a trademark of the Selchow & Righter Com- pany, and to disclaim, as does Ritam, any sponsorship or endorsement by Selchow & Righter. Robert Walls, President Ritam Corporation POB 921 Fairfield, IA 52556 * Scrabble is a registered trademark of Selchow & Righter Company. We apolo- gize for not acknowledging this in a prior article. . . . MH More Commbat I would like to thank George Stewart for his excellent and perceptive review, "Commbat: A Tele-Game for Two," in the December 1981 BYTE (page 100). He captured my motivation for creating Commbat in the first paragraph. The problems he mentioned of synchro- nizing both systems upon initial start-up 20 April 1982 © BYTE Publications Inc Circle 426 on inquiry card. 897 N. W. Grant Ave. • Corvallis, Oregon 97330 • 503/758-0521 Introducing the Enhancer ][: a new Standard which is improving the relationship between Humans and Apples. The Enhancer It can help your Apple It's keyboard become more sociable by remembering words or phrases which can be entered into the Apple by the mere touch of a key. Life can become even easier because the Enhancer ]t can remember what you typed while your Apple was busy talking to your disc (or doing other things). Naturally, it knows the difference between upper and lower case letters and what shift keys are supposed to do. It even knows to auto repeat any key held down. The Enhancer ][ replaces the encoder board making installation simple. Suggested retail price: $149.00. THE DAWN OF A NEW ERA FOR APPLE ]L' ■ ENHANCER It lip VIDEOTERM The time tested Videoterm 80 column card: • 80 characters x 24 lines • True decenders • 7 x 9 character resolution • Low power consumption • Compatible with most word processors • Softcard and CP/M compatible • Modem compatible • Most popular character set of any 80 column card • Alternate character fonts available Suggested retail price $345.00 y ' Xj ■ SOFT VIDEO SWITCH The Soft Video Switch is an auto- matic ver- sion of the popular Switch- plate. It knows whether it should display 40 or 80 columns or Apple graphics. It does the tedious work of switching video- out signals so you don't have to. The Soft Video Switch can be controlled by software. Any Videoterm with Firmware 2.0 or greater may be used with the Soft Video Switch. The single wire shift mod is also sup- ported. Package price is $35.00. ■ KEYBOARD AND DISPLAY ENHANCER The original Keyboard and Display Enhancer is still available for Revi- sion 0-6 Apples Con which the new Enhancer M will not fit). These Apples have memory select sockets at chip locations D1, El & F1. The Keyboard and Display Enhancer allows entry and display of upper & lower case letters with fully func- tional shift keys. It does NOT have user definable keys nor a type ahead buffer. The price is $ 1 29. 00. ■ ACCESSORIES Videoterm Utilities Disc $37.00 [includes) • Font Editor • Pascal Mid-Res Graphics • Applesoft Read Screen Utility • Top & Bottom Scrolling • Pascal Vidpatch • Graphics Template Character Set EPROMs $29. 00 ea • Half Intensity • Inverse • German • Katakana [Japanese] • Line Drawing Graphics (Expanded] • Spanish • French • Math & Greek Symbols • Super & Subscript Dvorak EPROM (Enhancer) $29.00 Lower Case Chip $29.00 mistered trademarks of Apple Computer Inc Circle 218 on inquiry card. a Screen Oriented Relational Database , designed to put \bu in control of a powerful information management system: quickly, easily, and at a price you can live with. Powerful •User defined CRTentry screens speed data input and editing. •Makes full use of *CP/M 2.0+ facilities for rapid access and retrieval. •User controlled security access codes. •Up to 32k records per relation with up to 8k per record. User Oriented •A consistent system of help messages, menus, and prompts assits the user in all phases of operation. •An English-like query format that is easy to use yet comprehensive. Clear Documentation •Our manual is concise, easy to understand, and indexed. $25 manual VISA.MC and COD welcome m INNOVATIVE SOFTWARE TECHNOLOGIES INC 3990 VARSITY DRIVE ANN ARBOR , MICHIGAN 48104 (313) 996-1890 JIRES: CP/M 2.0+ SYSTEM WITH ATLEAST 42K , 64-80 COLUMN SCREEN, ADDRESSABLE CURSOR AND,8 !! DISK DRIVES. "CP/M is a trademark of Digital Research, Inc. Letters. and keyboard sluggishness are a result of accommodating the TRS-80 Model Is RS-232 port. It cannot interrupt the pro- cessor when it has a character, so it must be operated in a polled-loop configuration in order not to lose data. As long as Model Is or their look-alikes are a signifi- cant part of the market this problem' will be necessary. I believe the first release of Cornmbat was the one reviewed. As a result of the synchronization problem, the current release, Cornmbat Version 2.1, has a split-screen dumb-terminal option that is presented to the user upon start-up. This mode can be entered without any particular worries as to timing by both participants, and when both are com- municating they can exit to the game. This mode also allows communications to be established through some of the dial-up services that can handle pass-through communications between users. At last report, the Atari version of this game was in production and should be available soon from Adventure Interna- tional, and an Apple version is on the way. The major feature of these different versions is that they will all play against each other. My intention is to keep Cornmbat system independent; as other systems become a significant portion of the market they will get their own com- patible version. Anyone who buys Cornmbat will be able to play anyone else who has ever bought it, regardless of equipment. The second game of this planned series is finished and will be marketed in the near future, and the third is coming along well. Robert A. Schilling 725 SE Vance Circle Palm Bay, FL 32905 No Contest Despite the "battle" for dominance por- trayed in the "Unix vs. CP/M" item in the November 1981 BYTELINES column (page 306), the position of the apologists for CP/M has become all but untenable. The implication that Unix and CP/M can be compared on the same terms is wholly misleading. Unix is a full-featured operat- ing system which is widely regarded as the finest ever written, while CP/M is little more than a program loader. The only reason for the continuing popularity of CP/M is summed up in the column's last sentence: "CP/M appears to have much more public-domain and com- mercial software for it than does Unix." As the computer community recognizes that Unix is bound to become the standard 16-bit microcomputer operating system, commercial applications software for it will inevitably begin to appear. And, since most Unix software is written in the powerful C programming language rather than in assembly language or some dialect of BASIC, we can be sure that the com- mercial software which will eventually be available under Unix will be of higher quality than that found in the CP/M market, John Lynn Roseman Urban Software Corporation 11 West 34th St. New York, NY 10001 Toward a Structured Assembler I have just finished reading the two-part article 'Toward a Structured 6809 Assem- bly Language" (November 1981 BYTE, page 370, and December 1981 BYTE, page 198), I found the article quite interesting, especially since I have been selling a struc- tured assembler (STASM09) package since 1980. STASM09 uses a pre-/post- processor to generate the appropriate in- ternal labels and to modify the listing to provide automatic indentation of the listing. (The indentation of the code pro- vides graphic display of the structure of the program module.) STASM09 provides the IF. . .ELSE. . . ENDIF but not the WHILE. . .ENDWHor REPEAT, . .UNTIL constructs described by Mr. Walker in his article, Instead, STASM09 provides a more general DO. . .ENDO construct with several methods to BREAK out of the loop. This allows both the WHILE and REPEAT functions to be implemented. In addition, STASM09 provides a COUNT function that can be used to control the number of times a loop is traversed. STASM09 is designed to run under the FLEX operating system from Technical Systems Consultants rather than the more industrially oriented Motorola operating system. STASM09 is available on a SVi-inch, single-density disk for $49.95, including shipping and handling, from Sansaska Systems, 3311 Concord Blvd., Concord, CA 94519. ^^r jSsflflHBHtti^^^^^^^^^^M^^^^^^^^^^^^MflflflflHii^ ' . -zr^r — IZr- ^ Our new guarantee covers two lifetimes. A lifetime of performance. All Memorex® disc packs and cartridges are now warranted to be free of defects in material and workmanship and will perform according to read/write capability for as long as they're properly used and maintained. Any product that fails to do so will be repaired or replaced by Memorex. No hassles, no excuses. Well help you isolate and correct any prob- lems that relate to the operation of our disc packs or cartridges for as long as you use them. It's that simple. To find out more about our new* Comprehensive Guarantee of Satisfac- tion and Service, call or write: Marketing Manager, Memorex Rigid Media and Components Division, 1125 Memorex Drive A lifetime of service. Second- §| HETH il^^DET \f MS-0064, Santa Clara, Cali- ly, you get a lifetime of technical |VIClVIV*rllC^ fornia 95052. Telephone: A Burroughs Company (408)987-0267. assistance from Memorex. Circle 479 on inquiry card. 1 1981 MEMOREX CORPORATION. MEMOREX ISA REGISTERED TRADEMARK OF MEMOREX CORPORATION. 'Effective 11/1/81 H ii« When You Have To Face A Deadline . . . I ill nee its introduction, Pa$cai/MT + * has been used to produce thousands of I professional solutions to industrial, business and systems level application J problems. In addition to implementing the complete ISO STANDARD, ] Pascal/MT + * contains a host of powerful features and facilities which make II program construction a snap! Pascai/MT + " is a total programming system including our native machine code com- piler, linker, Pascal-level debugger, disassembler, run-time subroutine library and the ex- clusive SpeedProgramming* m Package. With the advent of 16-btt machines and increasing customers demands, you can no longer afford to write programs in anything but a professionally constructed and profes- sionally supported package like Pascal/MT + * . MT MicroSYSTEMS has demonstrated its commitment to keeping your programs and programmers productive with our recent in- troduction of Pascal/MT + 86 and Pasca»/MT + 68K for the 8086. While Pascal/MT + * provides the capability to write non-portable programs when the need arises, portability between radically different machines is a reality while still translating into efficient, optimized native machine code. Our Pascal/MT + * compilers and Speed Programming Package are available on a wide variety of processors and operating systems, with more to come! We are continually work- ing to provide innovative solutions to the ever present problem of translating your ideas into software solutions. The Pascal/MT + * System Compiler: Generates ROM able Native Code • Complete ISO Standard (superset of Jensen & Wirth) Powerful Extensions Include: Modular Compilation, Direct production of binary relocatable modules • Dynamic strings • Chaining * Powerful Overlay system • Address and Size returning functions • Bit manipu- lation (test, set, clear, shifts) • Byte manipulation (high, low, swap) • Imbedded assembly language • Easy linkage to external assembly language • Full NEW and DISPOSE pro- cedures • Direct access to I/O ports • Fast floating point, both software and AMD 9511 • Accurate 18 digit BCD (fixed point, 14,4) • Include files • Hex literal numbers * and more. , . . . Arm Yourself With Pascal/MT+® >w> do oo 03 1^6 Linker: Combines relocatable modules into executable tiles * Can generate Hex format for use with PROM programming. ;trve Symbolic Debugger Variable display • High-level breakpoints by procedure/function name • Tracing/single 3 by Pascal statement * Procedure/function entry and exit trace available DhMfttembter: Combines a relocatable module with its listing file to produce interleaved Pascal and ap- proximate assembly language code. The Sp«ed Programming Package tTT1 ; The Speed Programming Package is an integrated set of tools which allows you to create Pascal/MT+ ' programs, check them for correct syntax and undefined identifiers, format them to display flow of control, and do this all within the editing environment before you ever invoke the compiler. Programmers like SpeedProgramming because it frees them from the time consuming chore of repeated compilations to correct simple syntactic and typing errors. Managers find that SpeedProgramming improves productivity, thereby reducing development costs. SpeedProgramming combined with our field tested Pascal/MT + " package gives you a comfortable, powerful, interactive programming environment in which to create your professional quality software Your products demand production quality tools. Order Pascal/MT + • with SpeedProgramming today? Screen Editor: User configurable • Standard random cursor movement, file access, search and replace, insert, delete, exchange, etc. * Structured language editing features such as automatic in- dent, fine adjustment, reading from and writing to a file, block text insertion and duplication uires: 24 x 80 CRT (or larger). ASCII Keyboard <7 bit data), random cursor addressing ctlve Syntax Scanner: > syntax errors in text being edited • Enters SPEED, puts cursor at error, prints error Variable Checker: hes undefined and mis-spelled variables before the compiler is invoked On Line Reformatted Beautify programs in seconds • Clearly shows structure and program flow, Source Code Management Toots: Automatic Modification Log and Backup utility program. PRICING: "Read carefully, some systems do not include the SpeedProgramming Package but do include the compiler, linker, disassembler, debugger and other utilities. AVAILABLE NOW! '8080V8085/Z80 without SpeedProgramming 56K or larger CP/M 808Q78085/Z80 complete including SpeedProgramming . 56K or larger CP/M 8080/8085/280 for special MP/M environments . Price $350.00 . . Price $475.00 . Contact Factory •8086/8088 without SpeedProgramming . . . Price $60000 CP/M -86 or MP/M-86, requires 1'1.6K program area 8086/8088 complete including SpeedProgramming . . Price $800.00 All 808678088 packages include 9511 and 8087 support and program to convert MT object fifes into Intel OBJ 8086 files Digital Research, Inc. is now the sole distributor for Pascal/MT+ , and is proud to add it to the Digital Research family of operating systems, languages and utilities. Available on 8" (3740) Single Density Disks Contact Distributors For Other Formats Pascal/MT+, CP/M, MP/M are trademarks of Digital Research, Inc. FOR: 8080/8085/Z80/8086 147 on inquiry card. M DIGITAL RESEARCH P.OBox579 160 Central Ave. Pacific Grove, CA. 93950 Phone No. 408/649-3896 TWX 910.360.5001 'All prices and specifictions subject change without notice. m^^BH CRT'S • PRINTERS • TELEPRINTERS MICROMAIL OFFERS THE LOWEST PRICES AND PERSONAL SERVICE. BETTER THAN EPSON!! $499.00 C. ITOH 8510 PRINTER •NEW* LIMITED STOCK $499.00 TEC 511 CRT •SAVE* foX DEC v LA 34 DA... $849.00 ^V DEC LA 34 AA $999.00 VT100 $1399.00 VT101 .............. ..CMU. VT 131. . . . . ................ CALL ANADEX DP 9500 DP 9501 DP 5000 1149.00 1149.00 $749.00 TELEVIDEO 910 $569.00 912 $689.00 920....... ...... $725.00 950 $939.00 925..... NEW!.. ...CALL TEXAS INSTRUMENTS 810/2..... ....$1299.00 (includes upper /lower case option) eio/2 vtc/cf ........$ ww.oo (includes u/1 case, forms control & compressed print) LETTER QUALITY PRINTERS DIABLO • 630 RO $1949.00 . 630 KSR... CALL . 1640 CALL .620 CALL GLUME . SPRINT 9/45 $1849.00 • SPRINT 9/35 CALL FOR PRICE NEC • 7700 SERIES • 3500 SERIES CALL FOR OUR LOW PRICES SOROC IA120 Id 140 IQ. 135 C. ITOH $675.00 $999.00 . $699.00 CIT 101 ... Special ... $ 1399.00 TELETYPE 43 PF(TTL) $899.00 [CALL TOLL FREE (800) 854-6028J To Order: Send check to MICROMAIL, P.O. Box 3297, Santa Ana, CA 92703. Personal or company checks require two weeks to clear. Visa/MasterCard accepted. CO.D. requires a 15% deposit. Handling: Add 3% to C.O.D. or credit card orders. Add 5% to 15% deposit on C/C and balance COD. NOTE: Handling charges are waived on orders pre-paid in advance by check Shipping: We ship FREIGHT COLLECT via UPS or Motor Freight Air and Express delivery is available. Prices subject to change without notice. ] WE SELL INTERNATIONALLY c HI a ra a i \ P.O. Box 3297 Santa Ana, CA 92703 II Phono: 714/731-4338 b— ■!! TWX: 910 595 U46 Letters Incidentally, I have noticed a possible problem with the macros defined in part 2 of the article. When an error condition is recognized in a macro, a long branch to the EXBUG monitor is inserted into the code. Since this can occur in code that is entirely relocatable, the relative offset of this error jump will be wrong any time the program is relocated. If this happens, the results will be entirely unpredictable and possibly very hard to debug. Derek Gitelson Sansaska Systems 3311 Concord Blvd. Concord, CA 94516 A Recipe for Standards I have been involved with the micro- processor standards work of the IEEE (In- stitute of Electrical and Electronics Engineers) Computer Society from its beginning (August 1977), so Chris Morgan's editorial in the November 1981 BYTE caught my eye. The question is "Can we agree on standards?" The correct answer is a qualified "Yes," and the "heated debate" usually occurs only when that qualification is violated. What is this qualification? The standard must be done right. The right way to establish a standard, once the need for a standard is apparent, requires three steps; • First define the objectives of the stan- dard that the potential users can agree on. • Examine the marketplace to see if there exist any widely accepted products that are designed to specifications that meet or are near the objectives. This examination can go four ways: (1) if there are no prod ucts, establish a design team of competent technical people to design specifications; (2) if there is one product fully meeting the objectives, adopt its specifications; (3) if there are one or more products close to the objectives but in some way inade- quate; establish a design team to adopt one (impartially, if possible) and to pro- duce from it adequate specifications; (4) if there are several incompatible products whose specifications fully meet the objec- tives, establish an impartial selection board to choose one set. (In this case it is usually too late to define a standard, but sometimes the need for it will reshape the marketplace.) • Write the specifications into a draft standard and take it out for public review. This is a necessary safeguard against per- 26 April 1982 © BYTE Publications Inc Circle 273 on inquiry card. DISCOUNT & BONUS COUPONS for PRINTERS, DISK DRIVES, DISKETTES, SOFTWARE, BOOKS and MORE! No gimmicks! For BIG SAVINGS on top-quality products from well-known suppliers, just circle (-25$) on your Reader Service Card and mail it today, or send your name and address to: FREE COUPONS P.O.Box 32010 Cleveland, Ohio 44132 NOTE: There is absolutely nothing phony about this offer. The companie extending these unusual bargains want and appreciate your business. The least expensive method of introducing top-quality products is by direct mail. The companies save money . . . and so do you. No tricks, no obligation. Just good business . . . Letters, sonal bias and technical incompetence in the designers. All responses to this review step must be dealt with before the stan- dard can be established. The draft stan- dard need not be modified for every re- sponse, since some of them will them- selves be biased or incompetent, but all responses must be considered. The American National Standards In- stitute (ANSI) and the IEEE, as a member of ANSI, are set up to develop standards by these procedures, and the standards so developed do receive wide public accep- tance. Although it is still being reviewed and revised, the proposed standard for the S-100 bus is an example of such success. What about the wrong way? Usually it is some variety of "Let's standardize on my way of doing it." A lot of standards are proposed this way, and some actually succeed. If they succeed, it is in spite of the attitude, not because of it, and then only because the proposer has done the WORD WHY DOES OUR SPELLING CHECKER COST LESS THAN THEIRS? Maybe we goofed by not charging more for The WORD. Our customers tell us we must be crazy, giving away this much software for only $75. What's wrong with it? Frankly, we're a little hurt when people ask us this question. We guess everyone must be getting used to paying $200 to $300 for decent software. Anything that costs less must be junk. Right?... WRONG!!! The WORD is not only cheaper, it's better! Available NOW for: 8" single CP/m', CDOS™ XEROX 820 (8" only) Intertec Superbrain™ Apple™ with CP/M Softcard 135.000 word dictionary) North Star™ Double/Quad with CP/M CP/M is a registered trademark of Digital Research OASIS SYSTEMS 2765 REYNARD WAY, SAN DIEGO, CA 92103 The WORD gives you more! The WORD gives you a 45,000 word dictionary that fits into less than 140K of disk space. The WORD works with your favorite text editor and marks mistakes in your document for easy, in-context, correction. i The WORD'S one-touch word review lets you add new words to the dictionary with a single keypress. You can build your own custom dictionaries too! • The WORD will look up the correct spelling of misspelled words. • The WORD analyzes your writing, counting words and showing you how often each word was used. The WORD has a special homonym helper feature to deal with these pesky words. » The WORD will find rhyming words, solve crossword puzzles, and much more! CALL TODAY! (714) 291-9489 technical homework and controls the marketplace (for example, IBM, which is known for this attitude). How does DIF fit in? [Editor's Note: DIF, for Data Interchange Format, is a method for representing data in a pro- gram so that it can be transported directly to other programs. See "DIF: A Format Between Applications Programs" by Can- dace E. Kalish and Malinda F. Mayer, November 1981 BYTE, page 174. j Soft- ware Arts is promoting DIF as a standard, using the "let's do it my way" approach. It may succeed at this, because Visicalc hap- pens to dominate the market. It may even be that DIF is a good technical proposal, but we cannot know this without the pro- per review procedures, which Software Arts has bypassed. I think it is unfortunate that monopoly industries like IBM and Software Arts can wield such Machiavellian powers as to im- pose on the rest of the world standards like EBCDIC (extended-binary-coded- decimal interchange code) and (possibly^ DIF without the benefit of good technical review. Tom Pittman Itty Bitty Computers POB 23189 San Jose, CA 95153 / concur with Mr, Pittman' s rational ap- proach to the establishment of a standard. However, our industry does not always behave rationally. I take issue with the implication that IBM and Software Arts are necessarily Machiavellian or even monopolistic. To be monopolistic, by definition a company must have exclusive control of the means of producing a pro- duct or service. Visicalc may be the best- selling microcomputer program of all time, but that hardly excludes competitors from offering their own types of spread- sheet programs. In the case of IBM, what- ever its past record has been in the main- frame market, its behavior in the personal computing market has been remarkably open and nonmonopolistic , if I may use that term . . . CM Multicolored Flayers, or The Atari Tutorial Debated I enjoyed reading Chris Crawford's "The Atari Tutorial, Part 3: Player- Missile Graphics" in the November 1981 28 April 1982 © BYTE Publications Inc Systems Group System 2800 computers. They're making people stand up and take notice. But then Systems Group products have always appealed to those who appreciate sensible value, high performance, un- matched reliability and prompt, courteous service. Through the years, Systems Group product acceptance in Z80 CPU, disk controller, I/O and memory boards have been the result of some very pur- poseful and carefully thought out engineering. Not to mention strict industrial quality produc- tion standards. That same effort has made System Group's new family of expandable System 2800 com- puters what they are today. Fast, reliable and powerful. System 2800 computer sys- tems are designed for a single user with 64K of memory or for up to as many as six separate users with additional add-in memory. They can easily ex- pand as your organization's needs grow. You can handle up to 8000 customers and 24,000 inventory items in our lowest cost dual floppy model and much, much more in our 40M byte hard disk models. And you can connect up to 12 terminals or printers and other add-on Systems Group floppy, tape and hard disk single or dual drive subsystems. Select CP/Mt MP/M f or OASIS tt operating systems to run all your word processing and accounting programs. No mat- ter what size organization you control, control- ling will be easier from now on. See the System 2800 from Systems Group, they're what computers should have been in the first place. | registered trademark of Digital Research ft registered trademark of Phase One Systems Dealer Inquiries Invited For dealers only, circle 396. All other inquiries, circle 397. Systems Group A Division of MEASUREMENT systems &. controls incorporated 1601 Orange wood Avenue Orange, California 92668, (714) 633-4460 TWX/TELEX 910 593 1350 SYSTEMGRP ORGE Be Permanently Impressed. The Expandable Computer Family from Systems Group. n n f3 n 1981 Today's Requirements Dual floppy single or multi-user system 1983 Tomorrow's Requirements 10M byte hard disk and floppy drive, single or multi-user system 1985 Your Future Requirements 40M byte hard disk and 20M byte tape back-up, single or multi-user system Circle 313 on inquiry card. VTrt ryx software What does the Oryx, an African antelope, have in common with reliable service? They are both almost extinct. Oryx Software wants to bring trustworthy ser- vice back to life. We're here to stay! GUARANTEED LOWEST PRICES! To celebrate our opening, we will absolutely guarantee the lowest prices. We will match any advertised price. Just show us the ad. ORDER TOLL FREE ■ Outside Wl 1-800-826-1589 SOFTWARE Graphpower 299.00 Tax Preparer '82 127.00 Real Estate Analyzer 127.00 Creative Financinq 127.00 Word Processor 1 425.00 Financial Projection 550.00 Mail Management 250.00 Micropro Wordstar 248.00 Mailmerge 90.00 Spellstar 169.00 Supersortll : 159.00 Context Connector 180.00 EasywriterfPro) 195.00 Easymover 45.00 Tellstarll 70.00 Easymailer 160.00 Datadex 249.00 Microplan Basic 419.00 Executive Secretary 212.00 Nevada CoBol 129. 00 Visicalc(3.3) 209,00 Apple Panic 25.00 SpellGuard 239.00 Computer Air Combat 53.00 PFS 4 Report 80.00 Sublogic Flight Simulator 28.00 SpeedStar 115. 00 Systems Plus Ace tg. Module 425.00 Micropainter 34.00 Zork II 33.00 Edu-ware (Apple) 35.00 Painter Power 34.00 Invoice Factory 148.00 Locksmith 99.00 Raster Blaster 25.00 SuperCalc 269.00 Visiterm 88.00 Visiplot 165.00 Visidex 209.00 Visitrend/Visiplot 249.00 Magic Window 79.00 Int I Grand Prix 25.50 Estimator 295.00 A-stat 79 145.00 SuperVyz 95.00 Graphic Software 19.00 CO. R.P.I 235.00 Real Estate Office Mngmt 425.00 Electronic I, II. or III 39.00 WordPro 3+ 295.00 Mailing List Program 50.00 Apple Doc 49.00 . . AND MANY MORE! Programs for popular microcomputers. Quoted prices valid for stock on hand and sub- ject to change without prior notice. Ask for our FREE catalog. For Peripherals see our other ad, page 382 Please: • Wisconsin residents - add 4% sales tax • Foreign orders - please add 15% • Add $2.50 for shipping per software and small item. Call regarding others. We Welcome: • Visa, MasterCharge - (Add 4%) • Checks (Allow 1-2 weeks for clearing) • COD (Add $1.50 per shipment) TOLL FREE ■ Outside Wisconsin: 1-800-826-1589 For Technical Info & in Wisconsin: 715-848-2322 %]| Oryx Software Dept. A. P.O. Box 1961 • Wausau, Wl 54401 Letters. 30 April 1982 © BYTE Publications Inc & BYTE (page 312). I believe, however, he has made an error. On page 319 he stated that multicolored players are not possible unless you use display-list interrupts. On the contrary, there is a way to produce multicolored players in BASIC very easi- ly. If you look on page III. 7 of the Atari Hardware Manual, you will see that set- ting the fifth bit of GPRIOR ($26F) at location 623 decimal will cause a logical OR function of the colors of player with player 1 and player 2 with player 3. The result is a choice of three colors in the overlapped region. The following pro- gram demonstrates this effect; 10 A=PEEK(106)-8:POKE 54279,A:REM SET UP PLAYER -MISSILE GRAPHICS 20 POKE 559,46:POKE 53277, 3:REM DOUBLE -WIDTH RESOLUTION 30 POKE 704, 26;POKE 705, 102:REM PLAYER & 1 COLORS 40 PMBASE = 256*A + 512 50 FOR l = 0TO 256:POKE PMBASE+l,0:NEXT I 60 FOR I = TO 7:READ A;POKE PMBASE + 48 + IANEXT I 70 DATA 255,255,195,195,195,195,255,255 80 FOR I = TO 7;READ A:POKE PMBASE + 176 + I,A:NEXT I 90 DATA 60,60,60,60,60,60,60,60 100 L=100:R=148:POKE 53248, LPOKE 53249 R 110 FORT = 0TO 1000:NEXTT 120 FOR 1 = 1 T0 24:L=L+1:R = R-1 130 POKE 53248, LPOKE 53249,R:NEXT I 140 FOR T = TO 300: NEXT T 150 POKE 623,32:REM SET BIT 5 OF GPRIOR 160 GOTO 160 Lines 50-100 POKE the player images into the player graphics buffer and set their horizontal positions. Lines 110-160 let you see the player images coming together and then the three colors being produced as one player. Remember that to move this three-colored player requires you to POKE the same horizontal position into the horizontal-position registers of both player and player 1. Peter Hecke 767 Bergen Blvd. Ridgefield, NJ 07657 Chris Crawford replies: Thank you for your program; it dem- onstrates the OR function of GPRIOR bit 5 very well. This technique, however, does not create a multicolored player. In- stead, it creates a three-colored object us- ing two players— certainly a useful tech- nique for "getting more for your money" with two players. If you are not otherwise using all your players, you can create a multicolored object by overlapping several players of different colors, With the technique you describe, you can get seven colors (the normal five plus two "overlap" colors), although you do not have full control over the overlap colors; without this technique, the most you can get is five colors (if you use all four players and the missiles as a fifth player). The method I referred to in my article modifies the display list to execute an assembly -language display-list interrupt routine to change the color register of a given player while the video image is be- ing drawn. This technique can produce one player that has multiple colors, but it has two disadvantages: first, it can only produce images striped horizontally with different colors; and second, unless you change the display list on the fly, the multicolored player cannot move vertical- ly (display -list interrupts are tied to a cer- tain horizontal line of the video display). Thanks for sharing your letter and pro- gram with other BYTE readers and me. Wanted: Education In Computerized Business Systems Students interested in obtaining a university education in the development of business-oriented computer systems should investigate the programs offered by the business schools. Paul Brady in his article on "Bridging the 10-percent Gap" (see the October 1981 BYTE, page 264) identifies the need for this type of train- ing, which combines courses on com- puters with courses on business organiza- tions and management skills. However, his comments do not indicate hat such programs already exist. Rigorous com- puter science programs provide excellent technical and theoretical training but are not typically designed to produce busi- ness-systems analysts and application pro- grammers. For further information on the educational issues involved and a survey of programs offered, see the article by Jay F. Nunamaker Jr., "Educational Programs in Information Systems," Communica- tions of the ACM, March 1981, and the in-depth report on "the DPMA Model" in Computerworld, September 21, 1981. Hugh Howson Professor Invite Universite du Quebec a Montreal Case postale 8888, Succursale "A" Montreal P,Q. H3C 3P8 ■ mmmwm A simple fad: The considerable benefits of a per- sonal computer like the Osborne 1® are often intangible, often exciting, and always expanding. The value of the Osborne 1 is clear and simple: $1795. Complete. $1795 includes this hardware: Z80A™ CPU with 64K RAM □ Dual floppy disk drives with 100K bytes storage each □ 5" CRT □ Business keyboard with numeric keypad and cursor keys □ RS-232C Interface □ IEEE 488 Interface □ Weather-resistant, portable housing □ Operates on European and American voltages □ $1795 includes this software: □ CP/M® Operating System □ WORDSTAR® word processing with MAILMERGE □ SUPERCALC™ electronic spreadsheet □ CBASIC® □ MBASIC® Available at your local computer retailer. Trademarks: Z80A: Zilog Corporation SUPERCALC: Sorcim Corporation Registered Trademarks: OSBORNE 1: Osborne Computer Corporation CP/M. Digital Research MBASIC Microsoft CBASIC: Compiler Systems, Inc. WORDSTAR, MAILMERGE: MicroPro International The Generic Word Processor A word-processing system for all your needs. You 11 be amazed by this product's versatility. Congratulations on your purchase of the GWP Inc. Generic Word- Processor System. We are sure that you will find this word processor to be one of the most flexible and conve- nient on the market, as it combines high unit reliability with low operat- ing costs and ease of maintenance. Before implementing the system, carefully study figure 1 to familiarize yourself with the main features of the GWP word-processing unit. Initialization The word-processing units supplied with your GWP are factory -fresh and Editor's Note: Once in a while we come across a product that's so useful we feel compelled to bring it to our readers' attention. The Generic Word Processor System (GWP) is such a product, incorporating the essentials of a word processor in a sublimely sim- ple form. With the manufacturers permission, we are reprinting the documentation for this product. After working with the GWP for several weeks, we're de- lighted by the feeling of total control that the system gives us and are certain you will be too. No more accidentally erased files, no damaged disks, no hardware problems .. . . SJW. Philip Schrodt Department of Political Science Northwestern University Evanston, IL 60201 uninitialized. Before they can be used, they must be initialized using the GWP initialization unit (see figure 2). Because of the importance of this unit, we designed it with a distinctive shape so that it will not be misplaced among the voluminous vital papers on your desk. To initialize a word-processing unit, carefully place the character in- sertion subunit into the left side of the initialization unit and rotate the word-processing unit approximately 2000 degrees clockwise while exerting moderate pressure on the word-pro- cessing unit in the direction of the in- itializer. Check for successful in- itialization by attempting a character insertion. If the insertion fails, repeat the initialization procedure. The word-processing unit will have to be reinitialized periodically; do this whenever necessary. (Warning: do not attempt to initialize the word- processing unit past its character dele- tion subunit. Doing so may damage both the word processor and the initializer.) Operating the Word Processor The GWP can perform all the basic functions featured in word processors that cost thousands of dollars more. Furthermore, because the GWP does not require electricity, it can operate during power blackouts, electrical storms, and nuclear attacks. By con- serving precious energy resources, it helps free our beloved country from the maniacal clutches of OPEC. Basic functions of the word pro- cessor are listed below: Inserting text: Use the character- insertion subunit to write in the words you wish to insert, applying moderate downward pressure to the unit. Be sure to write clearly so that the typist can follow what you have written. Deleting text: With moderate downward pressure, rub the charac- ter-deletion subunit across the text to be deleted. Repeat this procedure several times. The text will gradually disappear, whereupon you will be able tb insert new text. Underlining: Using the character- insertion subunit, place the unit slightly below and to the left of the first character you wish to underline. Move the unit to the right until you reach the last character to be under- lined. Bold face: Repeat the text-insertion procedure twice, pressing downward with greater pressure than you would normally apply. Move to beginning of text: With the text you are working on in hand, 32 April 1982 © BYTE Publications Inc " Adding manpower to a late software project makes it later. Brooks' Law: TheMytl ihI^T Don't waste man-months: Try CRTForm. Programming deadlines aren't met by adding more programmers to the job, but you can increase productivity, and reduce errors, by giving pro- grammers the tools they need. CRTForm is a program which produces an interface between the programmer and the end user. It saves time by: • Gathering application program specifications. • Providing friendly and consistent runtime communication with the end user. • Implementing CRT screen handling code. • Assuring programmers that the information which they receive is correct, • Allowing screen modifications and specifica- tion changes without requiring recompilation of application code. If you're writing applications code then CRTForm can save you time, as well asTeduce errors and provide a terminal independent solution to your own custom programming problems. The CRTForm system contains: • A forms manager that manipulates a random access file of input specification forms. • An editor that creates and modifies the specification forms. • A print utility that produces hard copy of forms and their specifications. • A terminal-independent runtime module in the machine language of your host processor. • A code generator that writes source code skeletons in Pascal, FORTRAN, COBOL, PL/ 1, BASIC, C, and even (for advance planning purposes) Ada. CRTForm is available for most micros and minis running under the CP/M-80, CP/M-86, UCSD, RMX-86 and Apple Pascal operating systems. Stat- eom will soon be releasing CRTForm under UNIX for both the 68000 and Z8000 processors. Please call or write for further information on OEM licensing arrangements, or for information about Stateom's other productivity tools. PROGRAMS WRITING PROGRAMS C OR P O R ATI Q N 57GB BALCDNES- SUITE 2Q2 AUSTIN TEXAS T'BT'SI R [Form are trademarks of Slate* h » T ™»'<*« CP/M Ds< UCSD-UCS^i^MX-..*: PHONE 512/451-0221 -ZHog. CHARACTER DELETION SUBUNIT CHARACTER INSERTION SUBUNIT Figure 1: The GWP System word-processing unit is composed of the character-insertion subunit (at right) and the character-deletion subunit (at left). INITIALIZATION UNIT Figure 2: The word-processing initialization unit, which should be operated over a wastebasket. PASTE NON-TOXIC AGES 6-12 Figure 3: The block text extraction and replacement units, commonly run in unison. SANSKRIT m s^ HIEROGLYPHICS iTtaU-illHsl t Figure 4: Sample type fonts illustrating the wide variety available with the GWP System. The manufacturer claims that if a language can be written, the GWP System can be adapted to it. move the unit to the beginning of the text. Move to end of text: Take the text you are working on and move the unit to the end of the text. Moving blocks of text: Block moves require use of the block text extraction unit and the block text re- placement unit pictured in figure 3. By means of the block text extractor unit, sever the paper immediately above and below the text you wish to move. Instructions for operating the extractor unit are etched on the side of the unit in Korean. If you still have difficulty operating the unit, call our service department for consulting help at our introductory fee of $50 per hour, or ask any 5-year-old child. After separating the text to be moved, open the lid of the block text replacement unit and, grasping the block text replacement medium appli- cation unit, spread the block text re- placement medium on the back of the text. Move the text to the new loca- tion and affix it to another sheet of paper with gentle but firm pressure. In a few minutes, your text will be permanently affixed in the new loca- tion. Other Features Page numbering: After writing your entire text, inscribe a 1 on the first page, a 2 on the second page, etc. When you finish, all of the pages will be numbered. Centering: Determine where the center of the page is by looking at it. The center is usually near the middle of the page. Place the text to be centered evenly on each side of the center. It is now centered. Special fonts: The GWP System is extremely versatile and easily adap- table to specialized type fonts such as Sanskrit, Amharic, and hieroglyphics (see figure 4). You will find these fonts valuable in business corre- spondence, particularly if you are in frequent contact with Vedic gurus, Egyptologists, or Ethiopian Airlines. Saving files: Put the work you have finished in a safe place, one where nobody will find it or spill coffee on it. If it is not disturbed, it will be there when you return. 34 April 1982 © BYTE Publications Inc 3&' ■ ... . . ,. ; . ■ ........ ■•. p,p ■ ; ;... . .... . .; . - ■ . ;, . INTELLIGENT PRINTER INTERFACE Free Your Computer from the Mundane Task of Printing Imagine being afc>le to use your computer seconds after beginning an extensive printout. Visualize your printout with page breaks, page numbering and titles, margins of your choice, indented carryover lines, on any size paper! Appreciate the time and money you 11 save by not waiting on your printer. SooperS pooler, a buffered printer interface, maintains control over your printer while you go on using your computer for more productive activities. Eliminate waiting while your printer pecks through a long document. SooperS pooler accepts information from your computer at up to 2500 characters per second and feeds it to your printer as fast as it can handle it — without using any of your computers memory or time! As soon as SooperS pooler has stored your document in its buffer, control of your :>mputer is returned to you. SooperSpooler features include: 16K Memory — Will handle most of your printing jobs (expandable, see options) Buffer Status Readout— Lets you know just how much data is stored Space Compression — Makes the best use of memory on columnar documents Pagination— Eliminates printout on page perforations Page Stops — For single sheet printouts Headers and Page Numbering — Give your listing a professional look Indentation on Carryover Lines — Easy to find the beginning of a line Self Test Routine — You instantly know that all is well All Features Software Controllable — Your program can take over Plugs into Most Computer Systems — Standard cables available $349.00! — 16K parallel I/O unit Options: • Serial Board— $95.00— Gives you the option of any combination of serial or parallel input or output. Can also be used for modem transmission. • Memory Expansion — $159.00 — Additional 46K for a total of 62K • Cables — Available per your application. TM SooperSpooler by Compulink — The missing link that gives your microcomputer mainframe printing. COMPULINK CORPORATION 1840 Industrial Circle, Dept. A Longmont, CO 80501 (303)651-2014 Order line: 800-525-6705 Dealer inquiries welcome Circle 96 on inquiry card. POWER SooperSpooler INTELLIGENT PRINTER INTERFACE BUFFER STATUS RESET tfg* SPACE COMPRESSION % PAGE m • VISA • MasterCard Checks Money Orders COD Add $3.00 per order for postage ; COD add S3. 00 Colorado residents add sales tax :es and Spec; Without Notice ications Subject to Change Deleting files: Take any files you no longer need and deposit them in the wastebasket. They probably will be gone in the morning. In most of- fices, this can also be accomplished by leaving the files in the open, for- getting to remove them from the copying machine, or writing CON- FIDENTIAL on the file in bold letters. Appending files: Place the first file on top of the second file. Treat the two files as though they were one file. Justification: Most word processors have little justification. This word processor has no justification at all, as it does not even lend prestige to the office where it is used, which is the justification for most word processors. Printing Files A printer for the GWP must be purchased separately. For conve- nience of operation, we recommend an ordinary typewriter and a typist. Give the text to the typist and tell him or her to type it. Printing speed can be improved by increasing the wages of the typist, threatening to withhold the wages of the typist, kidnapping pets, plants, or children of the typist, instigating intimidating tactics, and other conventional office-personnel management techniques. Printing speed can be decreased by asking to see the text, making continual changes in the text, asking the typist to answer the phone, decreasing the typist's wages, and installing a con- ventional electronic word processor. You will soon learn to adjust the printing speed to the optimal level for your particular needs. Copyright © 1981, Generic Word Processing Inc., Skokie, IL 60076 (WARNING:This system and ac- companying documentation are fully protected under the provisions of the Galactic Copyright Convention, ser, B, Rigal system, Code 56-*ADF6 45932030: f. Duplication is strictly prohibited without the permission of copyright owner. Violators will be prosecuted to the fullest extent of the law or devoured at the discretion of the copyright owner or such agents as the copyright owner may choose to designate.) ■ 36 April 1982 © BYTE Publications Inc CompuView New! CP/ M-86 For IBM PERSONAL COMPUTER The first available implementation of CP/M-86 for the IBM Personal Computer has the features needed to run the full range of CP/M-86 application programs. Included are serial and parallel printer support, a 'smart' screen driver which can emulate most popular CRT terminals, and double density 193K/drive disk capacity. The Tecmar Inc. Winchester hard disk & other peripherals are also supported. Innovative features include built in horizontal scrolling and screen line editing which lets the user extensively edit or re-enter any line on the screen for CP/M and application programs. Besides editing the line being typed in, the cursor may be moved to any line on the screen, and the line edited by overtyping or inserting and deleting characters. Typing the 'Return' key will then send the line, as it appears on the screen, to CP/M. While common on mainframe systems, this screen line editing is new to CP/M and greatly reduces the amount of retyping necessary due to mistyped or repeated commands. CompuView CP/M-86 for IBM Personal Computer. . . $325 VEDIT-86 with above purchase $100 8086 Software • VEDIT full screen editor for CP/M-86, SCP 86-DOS, IBM Personal Computer and IBM Displaywriter. Disk and Manual $195 • CP/M-86 BIOS for popular S-100 disk controllers and SCP 8086 computer. Source Code $90 V-COM Disassembler Finally a Z-80 disassembler for CP/M which produces easy to read code, a cross reference table and handles INTEL and ZILOG mnemonics. V-COM is exceptionally fast and produces an .ASM file directly from a .COM file. V-COM can accept two user created information files. One contains assignments of labels to 8 and 16 bit values; the second specifies the location of tables and ASCII strings. The resulting .ASM file will then contain labels and proper storage allocation for tables and strings. Each information file may contain nested 'INCLUDE' to other files. Each package includes a 30 page manual, sample program files and variations of V-COM compatible with the TDL, MAC and two types of ZILOG assemblers $80 SoftV\f3te An Industry Standard for CP/M & 8086 Uniquely User Oriented VEDIT is user oriented to make your editing for program development and word processing as fast and easy as possible. The customization (installation) process makes VEDIT the only editing package that allows you to determine your own keyboard layout and use any available cursor and function keys. Just think of the difference it makes in your ease of learning and usage to type cursor and function keys instead of memorizing obscure control characters. This customization is menu driven, extends to much more and takes only a few minutes. Unequaled Hardware Support The CRT version directly supports over 35 terminals (including ANSI standard) in its installation menu and utilizes 'smart' terminal features such as line insert/delete, reverse scroll, status line and reverse video. Function keys on terminals like the Televideo 920/950, Heath H19, and IBM 3101 are all supported. The memory mapped version is extremely flexible, supports bank select such as on the SSM VB3 and screen sizes up to 70 X 200. Sophisticated Full Screen Editing VEDIT gives you true 'what you see is what you get' full screen editing with an extensive set of features for creating and editing standard text files of up to one diskette in length. Very large files are effortlessly handled by VEDIT's ability to edit up to 47K of a file entirely in memory without performing any slow and annoying disk accessing. And you can handle multiple files, insert a specified line range of another file anywhere in the text and even change diskettes. User Oriented Features You get the features you expect, like searching, a scratchpad buffer for moving and rearranging sections of text, complete file handling on multiple drives and flexible macros. For ease of use VEDIT has features you won't find elsewhere, like automatic indenting for use with structured languages such as Pascal and PI/I- You are less likely to make a mistake with VEDIT, but if you do, one key will 'Undo' the changes you just made to a screen line. And if you run out of disk space with VEDIT, you can easily recover by deleting old files or even inserting another diskette. It is therefore no surprise that VEDIT is the industry standard for program development editing. Word Processing VEDIT is suitable for simple stand-alone word processing, or it may be used in conjunction with a text processor. Its features include word wrap, adjustable left margin, reformatting of paragraphs, word oriented cursor movement and deleting, and imbedding of printer control characters. VEDIT can print any portion of your file and display the cursor's line and column positions. Now for IBM Personal Computer XEROX 820 Ordering Please specify your micro- computer, video board or the CRT terminal version, the 8080, Z80 or 8086 code version and disk format. VEDIT - Disk and manual For 8080 or Z80 $145 For CP/M-86 or IBM MDOS . $195 Manual only $15 VISA and MASTER CARD Welcome. Apple II Softcard • TRS-80 II and I SuperBrain • Heath H8/H89 • Altos NorthStar • Vector • MP/M • IBM 1955 Pauline Blvd., Suite 200 Ann Arbor, Michigan 48103 (313) 996-1299 i I' M and MP U are registered trademarks of Digital Research, lnc Apple II is a registered trademark of Apple Computer, lnc Softcard is a trademark of Microsoft. TRS-80 is a trademark of Tandy Corporation. CompuView PRODUCTS, INC. Circle 450 on inquiry card. Here's just a taste of our great prices. To really feast your eyes, send for our new catalog. Great prices are only one feature of our new catalog. More important- ly, we think you'll find it to be a well-written, well-organized reference tool. When you receive our catalog, you get with it our committment to help you keep it up to date. Unlike most catalogs that are obsolete the moment they're printed, ours is designed to ac- commodate all the rapid-fire changes in micro-computer hard- ware and software. Its loose-leaf-binder format makes it a snap to add the new pages we'll send out on a regular basis. Our new catalog was developed on exactly the same principles as our business — to offer you the lowest possible prices combined with the highest quality of service. 16K RAM KITS .13.95 Set of 8 NEC 4116 200 ns. Guaranteed one full year. DISKETTES ALPHA DISKS 21.95 Single sided, certified Double Density 40 Tracks, with Hub-ring. Box of 10. Guaranteed one full year VERBATIM DATALIFE MD 525-01. 10. 16 26 50 MD 550-01. 10. 16 44.50 MD 557-01 10. 16 54 95 MD 577-01. 10 16 34 80 FD 3? or 34-9000 36.00 FD 32 or 34-8000 44 95 FD 34-4001 48.60 DISKETTE STORAGE 5V." PLASTIC LIBRARY CASE 2 50 8" PLASTIC LIBRARY CASE 3.50 PLASTIC STORAGE BINDER w/ Inserts 9.95 PROTECTOR 5 1 /4 " (50 Disk Capacity) 23.95 PROTECTORS" (50 Disk Capacity) 29 95 DISK BANK 5V 5 95 DISK BANK 8" 6.95 NEC PERSONAL COMPUTERS PC-8001A CPU 899.00 PC-8012A I/O 559.00 PC-8033A DISK I/O 125 00 PC-8031A DUAL DISK 899.00 ALTOS COMPUTER SYSTEMS Call Alpha Byte for our low Altos prices. ATARI COMPUTERS ATARI 800 699.00 ATARI 400 (16K) 339.00 ATARI 810 DISK DRIVE 44900 ATARI 850 INTERFACE . 449.00 ATARI 410 PROGRAM RECORDER 79 00 EPSON CABLE 35.00 MEMORY MODULE (16K). 89.95 JOYSTICK CONTROLLERS 10 00 PADDLE CONTROLLERS . 19.95 STAR RAIDERS 35.00 MISSILE COMMAND .35.00 ASTEROIDS 35,00 INTEC PERIPHERALS RAM MODULES 48K FOR ATARI 400 . 279.00 32K FOR ATARI 800 ....... 135 00 ACTIVISION ATARI CARTRIDGES LAZAR BLAST . . 21 95 SKIING 21.95 DRAGSTER . .21.95 BOXING 21.95 CHECKERS . 21 95 BRIDGE KAB00M 21.95 21.95 HEWLETT PACKARD HP CALCULATORS HP-11C LCD SCIENTIFIC 115.95 HP-12C LCD BUSINESS . 128.95 HP-37E BUSINESS 64.95 HP-32E SCIENTIFIC w/ STATS . 46.95 HP-33C Programmable Scientific 76.95 HP-41C Advanced Programmable 211.95 HP-41CV Advanced Prog 2K mem. 274.95 HP-41 PERIPHERALS HP-82106A MEMORY MODULE. . HP-82170A Quad Memory Module HP-82143A PRINTER/PLOTTER HP-82160A IL INTERFACE . . HP-82161A DIGITAL CASSETTE HP MATH PAC HP STATISTICS PAC HP REAL ESTATE PAC HP SURVEYING PAC HP STRUCTURAL ANALYSIS PAC. HP COMPUTERS HP-85A PERSONAL COMPUTER , HP SINGLE 5VDISK DRIVE HP DUAL DISK DRIVE HP-85A 16K MEMORY MODULE HP-7225B GRAPHICS PLOTTER HP PL0TER MODULE HP HP-IB INTERFACE HP STD APPLICATIONS PAC. HP GENERAL STATISTICS PAC HP GRAPHIC PRESENTATIONS HP VISICALL PLUS HP ROM DRAWER HP PRINTER/PLOTTER ROM . HP MASS STORAGE ROM HPRS-232 INTERFACE . PRINTERS ANADEX DP 9500 ANADEX DP 9501 C-IT0H 25 CPS PARALLEL. . . . C-IT0H 25 CPS SERIAL C-ITOH 45 CPS PARALLEL. C-ITOH 40 CPS SERIAL C-ITOH PR0WRITER PARALLEL C-ITOH PROWRITER SERIAL C-ITOH COMET I EPSON MX-80 EPSON MX-80 F/T EPSON MX-100 GRAPHIC . . EPSON GRAFTRAX IDS-445G PAPER TIGER. . . IDS-460G PAPER TIGER. . IDS-560G PAPER TIGER NECSPINWRITER3510S.ro. . NECSPINWRITER3530P.ro . 27.95 89.00 .324.95 .119.00 419.00 .29.00 .29.00 .39.00 29.00 ..39.00 .21.95 . 12.95 .19.95 .239.00 ..21.95 605.00 329.00 .83.00 .83.00 .159.00 .159.00 .39.00 .116.00 .116.00 329.00 1295.00 1295.00 1440.00 1495.00 .1770.00 1870 00 . .549.00 .695.00 289.00 $CALL SCALL . SCALL . .90.00 . 779 00 .945.00 .1195.00 2095.00 2095.00 NECSPINWRITER7710S.RO . 2545.00 NECSPINWRITER7730P.R0 2545.00 NEC SPINWRITER 7700 DSELLUM , 2795.00 NEC SPINWRITER 3500 SELLUM 2295.00 OKIDATAMICROLINE80 389.00 0KIDATAMICR0LINE82A 549,00 0KIDATAMICR0LINE83A 799.00 OKIDATA MICROLINE 84 .1199,00 0UME9/45 2149.00 MALIBU 200 DUAL MODE. .2695.00 CORVUS FOR S-100, APPLE OR TRS-80 MOD I, III Controller. Case/PS. . Operating System. A & T 5 MEGABYTES 3245.00 10 MEGABYTES 4645.00 20 MEGABYTES 5545.00 MIRROR BACK-UP 725.00 APPLE HARDWARE VERSA WRITER DIGITIZER. . ABT APPLE KEYPAD MICROSOFT Z-80 SOFTCARD MICROSOFT RAMCARD VIDEX 80x24 VIDEO CARD VIDEX KEYBOARD ENHANCER II . . . VIDEX ENHANCER REV 0-6 VIDEX SOFT SWITCH M & R SUPERTERM 80 x 24 VIDEO BD. SSM AI0 BOARD (INTERFACE) A & T. SSM AI0 BOARD (INTERFACE) KIT. . APPLE FAN T/G JOYSTICK T/G PADDLE VERSA E-Z PORT MICRO SCI A40 W/C0NTR0LLER. . MICRO SCI A40 W/0 CONTROLLER. . MICRO SCI A70 W/C0NTR0LLER. . . MICRO SCI A70 W/O CONTROLLER. . THE MILL-PASCAL SPEED UP PROMETHEUS VERSACARD SUPERCLOCK II LAZAR LOWER CASE + MICR0BUFFER II 16K MICROBUFFER II 32K WIZARD 80 COL VIDEO 259.00 .119.00 299.00 .159.00 299.00 129.00 .99,00 . .29.00 .315.00 .165.00 .135.00 .44.95 .54.95 34.95 . .21.95 479 00 409 00 .629.00 549.00 .329.00 .229.00 12900 59.00 .259.00 299.00 279.00 MONITORS NEC 12" GREEN MONITOR NEC 13" COLOR MONITOR. , SANYO 12" MONITOR (B&W). . SANYO 12" MONITOR (GREEN). SANYO 13" COLOR MONITOR ZENITH 13" HI RES GREEN M0N AMDEK COLOR I AMDEK RGB COLOR AMDEK RGB INTERFACE .199.00 .399.00 249.00 .269.00 .469.00 .139.00 .389.00 859.00 169.00 38 BYTE April 1982 Circle 17 on inquiry card. MOUNTAIN HARDWARE 100-3 SINGLE HEAD 80 TRK 100-4 DUAL HEAD 80 TRK 299 00 429 00 CPS MULTIFUNCTION BOARD * 199.00 SUPERTALKER SD200 259 00 ROMPLUS W/ KEYBOARD FILTER 179.00 ROMPLUS W/0 KEYBOARD FILTER 130 00 KEYBOARD FILTER ROM 49 00 COPYROM 49 00 MUSIC SYSTEM 369.00 ROMWRITER 149 00 APPLE CLOCK 252 00 A/D + DVA 299.00 EXPANSION CHASSIS 625 00 CALIF. COMPUTER SYSTEMS S-100 BOARDS 2200A MAINFRAME 459 00 2065C64K DYNAMIC RAM 53900 2422 FLOPPY DISK CONT & CP/M* 359.00 2710 FOUR SERIAL I/O . 27900 2718 TWO SERIAL/TWO PARALLEL I/O 269.00 2720 FOUR PARALLEL I/O 199.00 2810 Z-80 CPU 259.00 APPLE BOARDS 7710A ASYNCHRONOUS S. INTERFACE 149. 00 7712A SYNCHRONOUS S INTERFACE 159.00 7424A CALENDAR CLOCK 99. 00 7728A CENTRONICS INTERFACE 105.00 VISTA COMPUTER CO. APPLE VISION 80-80 COL CARD 329.00 APPLE 8" DISK DRIVE CONTROLLER 549.00 MODEMS NOVATION CAT ACOUSTIC MODEM 145.00 NOVATION D-CAT DIRECT CONNECT 165 00 NOVATION AUTO-CAT AUTO ANS 219.00 NOVATION APPLE-CAT 349.00 UDS 103 LP DIRECT CONNECT .175.00 UDS 103 JLP AUTO ANS 209.00 HAYES MICROMODEM II (APPLE) 299 00 HAYES 100 MODEM (S-100) 325 00 HAYES SMART MODEM (RS-232) 249.00 HAYES CHRONOGRAPH 225.00 LEXICON LX-11 MODEM 109.00 RACAL VADIC 1200 BAUD/21 2A 795.00 TERMINALS TELEVIDE0 910 639.00 TELEVIDEO 912C . . 745.00 TELEVIOEO 920C 830.00 TELEVIDEO 950C 995.00 ZENITH Z-19 799.00 TRS-80 MOD I HARDWARE PERCOM DATA SEPARATOR 27.00 PERCOM DOUBLER II 159.00 TANDON 80 TRACK DISK DRIVE 429.00 TANDON 40 TRACK DISK DRIVE . 289.00 LNW DOUBLER W/ DOSPLUS 3. 4D . 159.00 MOD II! DRIVE KIT 649.00 MORROW DESIGNS FLOPPY DISK SYSTEMS Controller. P.S., Microsoft Basic, CP/M' A & T. DISCUS 2D (Single Drive - 500K) . 869.00 DISCUS 2D (Dual Drive - 1 MEG). 1499.00 DISCUS 2 + 2 (Single Drive - 1 MEG) 1099.00 DISCUS 2 + 2 (Dual Drive - 2 MEG) 1999.00 HARD DISK SYSTEMS Controller. PS.. Microsoft Basic. CP/M* A& T, DISCUS M10 (10 Megabytes) 3099.00 DISCUS M26 (26 Megabytes) . 3749.00 ISOLATORS ISO-1 3-SOCKET ISO-2 6-SOCKET BARE DRIVES TANDON 5 1 A INCH 100-1 SINGLE HEAD40 TRK 100-2 DUAL HEAD 40 TRK . 5395 .53.95 219.00 299 00 TANDON THINLINE8 INCH 848-1 SINGLE SIDE 459 00 848-2 DUAL SIDE 549 00 MICRO PRO APPLE CP/M" WORDSTAR* SUPERSORT* MAILMERGE* DATASTAR* SPELLSTAR* CALCSTAfl* CP/M' WORDSTAR SUPERSORT MAILMERGE DATASTAR SPELLSTAR CALCSTAR MICROSOFT APPLE FORTRAN* BASIC COMPILER* COBOL* Z-80 SOFTCARD . RAMCARD. TYPING TUTOR OLYMPIC DECATHLON. TASC APPLESOFT COMPILER CP/M" BASIC 80 BASIC COMPILER FORTRAN 80 COBOL 80 MACRO 80 mu MATH/mu SIMP mu LISP/mu STAR 249 00 145.00 90.00 21500 169.00 169 00 310 00 195.00 11000 245.00 195.00 239.00 165.00 315.00 595.00 299.00 159.00 17.95 24.95 159.00 299.00 319.00 369.00 595 00 189.00 219 00 175.00 APPLE SOFTWARE MAGIC WINDOW 79.00 MAGIC SPELL 59.00 BASIC MAILER 59.00 APPLE PIE 99.00 DB MASTER ... 179.00 PfS: PERSONAL FILING SYSTEM 7900 PFS: REPORT 79.00 Z-TERM* 89.95 Z-TERMPRO*. 129.95 ASCII EXPRESS 63.95 HAYDEN APPLESOFT COMPILER 149.00 EASY WRITER-PRO 199.00 EASY MAILER-PRO 79.00 EXPEDITER II APPLESOFT COMPILER . .73.95 A-STATCOMP STATISTICS PKG 129.00 SUPER TEXT II... 129.00 FINANCIAL PARTNER. 199.00 LISA 2.5. .59.95 SUPERSCRIBE II 99 95 CONTINENTAL SOFTWARE G/L 19900 A/R. .... .199.00 A/P 199.00 PAYROLL 199.00 PROPERTY MGMT 399.00 THE HOME ACCOUNTANT 59.95 PERSONAL SOFTWARE DESKTOP PLAN II ... . .199.00 VISIPLOT . . 17900 VISITREND/VISIPLOT 239.00 VISIDEX 199.00 VISITERM 79.00 VISICALC ... 199.00 VISIFILES 209.00 CP/M® SOFTWARE THE WORD-SPELL CHECK 75.00 d BASE II 599.00 SUPER CALC 229.00 SPELLGUARD 239.00 P&TCP/M* MOD II TRS-80 .175.00 COMMX TERMINAL PROG. ..82.50 C BASIC 2 .115.00 PASCAL Z 349.00 PASCAL MT+ 439.00 PASCAL/M 205.00 SYSTEMS PLUS - G/L. A/R. A/P. P/R 1799.00 CONDOR I .579.00 CONDOR II 849.00 DIGITAL RESEARCH MAC 89.00 SIO 6900 ZSID 97 00 PL/ 1-80 43900 SUPERSOFT DIAGNOSTIC I 69.00 DIAGNOSTIC II 89 00 X" COMPILER 179 00 UTILITIES I 59.00 UTILITIES II 59.00 RATFOR 89.00 FORTRAN 239.00 TRS-80 GAMES TEMPLE OF APSHAI 34.95 HELLFIRE WARRIOR 34.95 STAR WARRIOR 3495 RESCUE AT RIGEL 24.95 CRUSH. CRUMBLE AND CHOMP 24.95 INVADERS FROM SPACE 17.95 PINBALL 1795 STAR TREK 3.5 . 17.95 MISSILE ATTACK 18.95 STAR FIGHTER 24.95 TRS-80 SOFTWARE NEWDOS/80 2 MOD I. II 139 00 LAZY WRITER MOD I. II 165.00 PROSOFT NEWSCRIPT MOD I. Ill 99.00 SPECIAL DELIVERY MOD I. Ill 119 00 X-TRA SPECIAL DELIVERY MOD 1. HI, 199.00 TRACKCESS MOD 1 24 95 OMNITERM SMART TERM. MOD 1. Ill 89.95 MICROSOFT BASIC COMP FOR MOD 1 165 00 LDOS5.1 MODI. II 159.00 APPLE GAMES PERSONAL SOFTWARE CHECKER KING 21.95 GAMMON GAMBLE 1 21.95 BRIDGE PARTNER 21.95 MONTY PLAYS MC NOPOLY 29.95 ZORKI 32.95 ZORK II 32.95 MONTY PLAYS SCF BABBLE 34 95 BRODERBUND GALAXY WARS 20.95 ALIEN RAIN (AKA GALAXiAN) 20.95 ALIEN TYPHOON 20.95 APPLE PANIC 24.95 MIDNIGHT MAGIC 29.95 SPACE QUARKS 24.95 AUTOMATED SIMULATIONS INVASION ORION 20.95 STAR WARRIOR 32 95 TUES. MORNING QUARTERBACK . 25.95 CRUSH, CRUMBLE AND CHOMP 24,95 THE DRAGON'S EYE 20.95 MUSE SOFTWARE ROBOT WARS .32.95 THREE MILE ISLAND 32.95 ABM. 20.95 GLOBAL WAR . .20.95 CASTLE WOLFENSTEIN 24.95 ON-LINE SYSTEMS WIZARD AND PRINCES 29.95 MISSILE DEFENSE . .25.95 SABOTAGE 20.95 SOFT PORN ADVENTURE . 24.95 THRESHOLD 31.95 JAW BREAKER - 24.95 CROSSFIRE . 16.45 TIME ZONE 69.95 H/R FOOTBALL 32.95 H/R CRtBBAGE .20.95 PEGASUS II 25.95 SIRIUS SOFTWARE SPACE EGGS 24.95 GORGON 32.95 SNEAKERS . 24.95 EPOCK 29.95 BEER RUN 24.95 HADRON 29.95 PULSAR II 24.95 EPOCK. 29.95 EDU-WARE PERCEPTION PKG 19.95 COMPU-READ 24.95 STORY TELLER 18.95 COMPU-MATH ARITHMETIC 39.95 COMPU-MATH FRACTIONS 34.95 COMPU-MATH DECIMALS 34.95 COMPU-SPELL (REQ. 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Add $2.00 for standard UPS shipping and handling on orders under 50 lbs, delivered in continental U.S. Call for shipping charges over 50 lbs. Foreign, FPO and APO orders, add 15% for shipping. Californians add 6% sales tax. Prices quoted are for stock on hand and subject to change without notice. 31245 LA BAYA DRIVE, WESTLAKE VILLAGE, CALIFORNIA 91362 Circle 17 on inquiry card. CP/M is a reg. trademark of Digital Research. 'Requires Z-80 Softcard BYTE April 1982 39 Ciarcia's Circuit Cellar Use Infrared Communication for Remote Control The Texas Instruments SN76832AN Infrared Remote-Control Receiver simplifies the tough job of receiving modulated infrared light. Steve Ciarcia POB 582 Glastonbury, CT 06033 Two dozen images of Howard Cosell danced before my eyes. Sud- denly there were two dozen images of acid indigestion, and then, just as suddenly, Howard Cosell was back. Undaunted, I stood my ground, which happened to be in the televi- sion department of a large store a few miles from home. I was wielding a small box covered with push-button switches, trying out a display of About the Author Fifteen years ago, Steve Ciarcia (pronounced "see-AR-see-uh") gave up a promising career as a security guard for the Famous Writers' School to become an electrical engineer and computer consultant. He has experience iti nuclear instrumentation, process control, digital design, product development, and marketing. In addition to writing for BYTE magazine, he has published several books, in- cluding Build Your Own Z80 Computer (BYTE Books, 1981). When he's not working in his Circuit Cellar, he enjoys cooking such foods as Eggplant Siciliana and Shrimp Proven^ale and driving his DeTamaso Pantera sports car. remote-controlled TV sets. There has been a silent revolution going on in the TV remote-control business. Silent indeed. No longer do Detecting an information-bearing infrared beam in an infrared-saturated environment is a signal-to-noise horror show. the control boxes emit ultrasonic im- pulses that drive all the dogs in the household into hysterics. Today's remote-controlled TV sets receive viewers' instructions on beams of in- frared light. The silent revolution has also made controlling the sets easier. Ultrasonic remote-control units, because of their complexity and cost, usually have had only two or three control chan- nels, making channel changing a tedious, repetitive task and limiting the set functions that could be remotely commanded. Infrared-light units are not only practical; they have become much more sophisticated, often making available thirty or more control chan- nels for less than the cost of a pair of ultrasonic transducers. To supply the demand for support circuitry to build remote-control systems, several semiconductor man- ufacturers (such as General Instru- ment, Hitachi, Signetics, and Texas Instruments) are producing integrated circuits that encode and decode the command information used in these TV remote controls. Most encoder chips are designed to accept a key- board input and directly modulate an infrared light source. At the receiving end, the encoded data stream is decoded by a decoder chip and a few discrete components. I decided to buy a pair of infrared encoder/decoder chips and build a 40 April 1982 © BYTE Publications Inc RELATIVE SPECTRAL CHARACTERISTICS RESPONSE OF TYPICAL SILICON PHOTOTRANS1STORS AND PHOTODIODES OUTPUT OF TUNGSTEN SOURCE AT 2870 K- 1.0 0.8 0.2 -ULTRAVIOLET BLUE 0.7 0.8 0.9 X-WAVELENGTH-/i.m RED INFRARED Figure 1: Relative spectral characteristics of infrared light-emitting diodes and photo- diodes. quick and dirty remote-control unit. It was going to be so easy. Not so fast! There was a missing link: detecting the beam of infrared light so it could be decoded. To Find a Missing Link Was I going to let a little thing like a beam of light stop me? Of course not. I started investigating how to sense a beam of infrared light. Once again I found myself working on a topic about which I could find very little published information of use in practical experimentation. I suspect there have been few magazine articles dealing with infrared-light communication because of the diffi- culty in detecting an information- bearing beam of infrared light in an infrared-saturated environment. It's a signal-to-noise horror show! The sen- sitivities and dynamic ranges required are beyond simple amplifier-design techniques. My goal of building an inexpensive remote-control scheme using TV-set encoder/decoder chips therefore had to wait until I first designed a reliable infrared com- munication receiver. This article contains both a discus- sion of optical communication and a construction project of a useful in- frared-light transmitter /receiver in- terface for use with a personal com- puter. Along the way I attempt to answer some basic questions includ- ing the following: In what kind of ap- plications can light transmission be useful? Why use infrared rather than visible light? What is the best choice of optoelectronic components for each application? Why Use Light? Light is used in communication for two major reasons: the medium's immunity to certain forms of interference and the relative ease of providing security for the communi- cations link. Electrically noisy motors and other equipment generate electro- magnetic interference (EMI) that can play havoc with radio-wave trans- missions, and ambient noise can disrupt ultrasonic communication. These problems do not bother light beams, and a protected line-of-sight beam path or waveguide provides fair security against unauthorized inter- ception. Light can also be used in providing physical security for premises; a prowler might step over a tripwire, but he wouldn't know to avoid an in- visible shaft of infrared light aimed at a detector in an alarm system. What Is Infrared Light? The segment of the electromagnetic spectrum that we perceive optically as visible light is narrow. On both sides of this band of visible light are regions of radiation that we can't see but which otherwise exhibit similar optical properties. Radiation of wavelengths shorter than we can see is called ultraviolet (UV) light, while wavelengths longer than we can see form infrared (IR) light. Any warm object radiates some amount of in- frared radiation. (Some may quibble with my use of the term "light" to discuss radiation that cannot be seen. I feel that any radiation that can be manipulated op- tically [by lenses and the like] should be called light, and that's how I am using the term in this article.) The spectral graph of figure 1 shows that the visible band has wave- lengths between about 400 and 700 nm (nanometers). Within the range of 400 to 700 nm, the different frequen- cies are perceived as different colors. For example, a light beam of 550-nm wavelength is perceived as green. What we perceive as white light con- tains all the visible frequencies. Transmitting information on a beam of light is done much the same way as on a radio wave. The light must be amplitude-modulated at some carrier frequency, say 40 kHz. This allows the receiver to differen- tiate between the light coming from the transmitter and unmodulated am- bient light. The data to be transmitted can be modulated onto the carrier in a number of ways, including amplitude and frequency modulation, pulse- width modulation (PWM), and pulse- code modulation (PCM). For my application of a simple op- tical remote-control system, the less complicated PCM technique seemed best. This merely consists of turning the 40-kHz-modulated light on and off. At the receiving end, the presence of light is interpreted as a logic 1 and the absence of light as a logic 0. Why use so high a carrier frequen- cy? We have to use a frequency high enough that the communication is not susceptible to interference. The operating environment of our in- frared system may contain such sources of interference as fluorescent lights, which flash at 120 Hz, or television sets, whose screens emit light with interference patterns at over 15 kHz. For open-air optical communication, frequencies at or above 40 kHz are preferred. Any electrically excited light source can be amplitude modulated, but not April 1982 © BYTE Publications Inc 41 EMITTED PHOTONS Si 3 N 4 - AV^ f / ^DIFFUSED p LAYER C J / / / Zn DOPED / /-p/n JUNCTION ?5 fe^. _ [ J_ [ [ C_sjzzzi _±A »:■>»:-' • :■ :-:-i-r-: : :."- r: n a c d fditayy :-r-i-i-z->>>i->i-:-i-z-5l- " p/n JUNCTION 2 5/im 25/im GaAsP EPITAXY GaP OR GaAsP SUBSTRATE - n DOPED I- • 150um i ^— AuSn BACKSIDE CONTACT Figure 2: Cross section of the structure of a standard visible red light-emitting diode. Blue LEDs at Last Longtime readers of BYTE may recall Steve's article from several years ago on a self-refreshing LED graphics display (see reference 2). In it, he described how single-color graphic im- ages can be formed on display panels containing arrays of many red light- emitting diodes and suggested that multicolor images could be displayed on a panel that contained arrays of triads of different-color LEDs. But his suggestion was ahead of technology. At that time, no practical method was known for making an LED that could emit blue light. Now the blue-light barrier has been broken, and in a way eminently suit- able to flat-panel graphics displays. In October 1981, the Sanyo Electric Com- pany of Japan unveiled an LED lamp component that contains two separate LED chips, one of which emits blue light at a wavelength of 480 nano- meters (see reference 3). The blue- emitting chip is formed from two Hquid-phase-epitaxial layers of silicon carbide grown on a silicon-carbide wafer. The other chip , made of gallium phosphide with four epitaxial layers, can emit both red light at 700 nano- meters and green light at 565 nano- meters. A single component that can produce all three additive primary col- ors makes possible a full-color, flat- panel LED graphics display. The voltage potential dropped by the blue LED chip is about 3.5 V, pro- ducing 2 mcd (millicandelas) of light, while the two-color chip drops 2 V for 3 mcd of green light and 1.9 V for 3 mcd of red light. Thus we see that real components reflect the theoretical predictions of greater efficiency at longer wavelengths. . . . RSS all of them at 40 kHz. Modulating a 100-watt incandescent light bulb at such a high frequency is out of the question: the thermal time constant of the filament is much too long. The only light sources capable of switch- ing at such a frequency are elec- troluminescent devices, of which the light-emitting diode (LED) is the least expensive and most familiar. In a light-emitting diode, shown in figure 2 on page 42, light is generated when a forward-bias current is ap- plied. This causes electrons to be in- jected into the n-type (negative- doped, electron-rich) semiconductor material and holes (shortages of elec- trons) to be injected into the p-type (positive-doped, electron-poor) material. When the injected electrons and holes recombine with the majority carriers at the p/n junction, energy is released in the form of photons. The pattern of radiation emission can be controlled somewhat by reflective surfaces within the mounting struc- ture and by plastic lenses. Generally, a spherical dome lens with a narrow beam width is best for communica- tion. The color of the light emitted de- pends upon what semiconductor materials are used in the p/n junction and how they are doped (seeded with selected impurities): the amounts of energy released in the electron/hole recombinations of different materials vary, and the wavelength (and there- fore the color) of light varies in a direct relation to the amount of energy contained in its photons. Most of the semiconductor materials used in LEDs are com- pounds of gallium: gallium arsenide phosphide (GaAsP, which emits red, orange, or yellow light), gallium phosphide (GaP, green emitting), gallium aluminum arsenide (GaAlAs, red emitting), and gallium arsenide (GaAs, which emits infrared photons at about 900 to 1000 nm). The effi- ciency of an LED depends upon wavelength. The longer the wave- length, the higher the efficiency (see the text box "Blue LEDs at Last"). Operating at longer wavelengths, infrared LEDs are more efficient than visible-light red or green LEDs; IR LEDs are therefore preferred for line- of -sight beam breaking or communi- cation. For a given power input, an IR LED produces a brighter light than a green LED. Many IR LEDs have radiant-power outputs of more than 10 mW (milliwatts) — for instance, the TIL39 component I have been experi- menting with has an 11-mW output at 940 nm. Efficiency is important, because an LED is almost a point source of light. The illumination it casts on a surface is proportional to its brightness and inversely proportional to the square of the distance to the surface. If we want our open-air communication link to operate over distances as great as 10 meters, our LED light source must be very bright to produce an ac- ceptable signal-to-noise (S/N) ratio using an ordinary-sized receiving photosensor measuring perhaps 0.1 cm 2 (square centimeter). Other incentives for using IR light are reduced sensitivity to ambient visible light, greater ability to pierce through fog or smoke, and better re- flection off most surfaces for a greater chance that the receiver will be able to see the light source. Choosing the Light Detector Choosing the proper light detector is as important as selecting the light emitter. Selectivity, response, and in- herent noise are important considera- tions. There are many materials which function as photoconductors. The simplest are bulk materials such as cadmium selenide (CdSe), lead sulfide (PbS), and cadmium sulfide (CdS). 42 April 1982 © BYTE Publications Inc Generally these materials exhibit poor temperature stability and are sensitive over a very broad range of wavelengths. The familiar semiconductors ger- manium (Ge) and silicon (Si), on the other hand, are sensitive chiefly to the near-infrared (wavelengths close to the visible range) light radiated by IR LEDs. Two types of devices that use silicon and germanium are photo- diodes and phototransistors. Photo- transistors are constructed in much the same manner as commonplace planar-diffused transistors. The base area is usually made large to provide an area into which incident light can penetrate and generate electron/hole pairs. Phototransistors are subject to the variation in performance typical of all transistors. Many of the bad traits of photo- transistors are eliminated in PIN photodiodes. The term PIN is an acronym meaning that the compo- nents are made from three layers of different types of semiconductor material: p-type, ''intrinsic/' and n-type. A PIN photodiode is one in which two heavily doped p and n regions are separated by a lightly doped region (which exhibits mostly properties intrinsic to the substance). Its large depletion region (interface region between the p-type and intrin- sic layers) provides the PIN photo- diode with much faster speed, lower noise, and greater efficiency at longer wavelengths. Photo 1 shows a TIL413 infrared- sensitive PIN photodiode (right) and a TIL39 infrared light-emitting diode (left). Ready-Made IR Detector Designing a reliable infrared-light detector/receiver is no simple task; it has been the major obstacle in design- ing any infrared communication sys- tem. The engineer must coax his receiver into extracting the trans- mitted data from a dismaying amount of background noise, and he must take care that his design will with- stand the impairments to theoretical performance caused by deviations from ideal component values and manufacturing techniques. But there m ^ Sj Photo 1: The TIL413 infrared-sensitive PIN photodiode (right) and the TIL39 in- frared light-emitting diode (left). Photo 2: Prototype of the infrared-light remote-control or communication re- ceiver of figure 4. is nothing conceptually complicated in the receiver, just a photodiode and a series of amplifiers and filters. I haven't presented an infrared communication system before now because I couldn't design one that I felt readers could successfully duplicate. But recently I discovered that an integrated circuit has been de- veloped to do all the hard work. Texas Instruments recognized the need and designed a chip which eliminates all the frustrations in building the IR receiver. The new component is the SN76832AN Infrared Remote-Con- trol Receiver. This chip replaces a combination of several integrated cir- April 1982 © BYTE Publications Inc 43 VCO TIMING ;r2 r /* SUPPLY DECOUPLING 10 Dl TIL413 PHOTO - DIODE LI) ►Rl 11 A, *C5 vcc VCO .CI TUNED INPUT STAGE ;c3 m DECOUPLING CAPACITOR C2 COUPLING CAPACITOR S ;c7 m DIFFERENTIAL DECOUPLING ^ R3 ;cio LOOP FILTER ;cs rh AMPLIFIER CAPACITORS s HHV :c6 OUTPUT FILTER CAPACITOR m OUTPUT ENABLE 4 DATA OUTPUT VCO TIMING CAPACITOR [ 1 VCO TIMING RESISTOR [ 2 OUTPUT ENABLE [ 3 DATA OUTPUT [ 4 LOOP FILTER [ 5 SECOND AMPLIFIER DECOUPLING [ 6 SECOND AMPLIFIER INPUT [ 7 SECOND AMPLIFIER DECOUPLING [ 8 SN76832AN 16 ] V CC 15 ] GROUND 14 ] LOCK FILTER 13] FIRST AMPLIFIER DECOUPLING 12 ] FIRST AMPLIFIER OUTPUT 11 ] FIRST AMPLIFIER INPUT 10] AMPLIFIER SUPPLY DECOUPLING 9 ] GROUND Figure 3: Block diagram of the internal structure of the Texas Instruments SN76832AN Infrared Remote-Control Receiver, cuits and discrete components. It con- nects directly to a PIN photodiode and is designed to receive and detect digitally encoded information modu- lated on a carrier (typically 40 kHz). It has an open-collector gated output suitable for direct operation with a microprocessor. For the benefit of readers of BYTE, the Micromint will be distributing a kit that includes the SN76832AN (see page 49). A block diagram of the SN76832AN receiver chip is shown in figure 3 . In- side the receiver chip, the signal from the photodiode is connected to an amplifier with an input impedance of 220 kilohms and a typical gain of 1.6 million volts/amp at 40 kHz. The output of this first amplifier stage is fed to a differential amplifier coupled to the demodulator section. The receiver chip demodulates the signal by comparing its amplitude and phase with that of reference signals produced by a voltage-con- trolled oscillator (VCO) and a fre- quency divider. The bandwidth and capture frequency are controlled by external passive components. The de- modulated output signal is filtered and gated by the output-enable con- trol signal. (A high level on the output-enable line causes the demod- ulated signal to appear on the output line. If the demodulated signal is to be constantly present, the output-enable line should be tied high.) Figure 4 on page 45 is a schematic diagram of the completed circuit for a very sensitive IR receiver which oper- ates at a carrier frequency of 40 kHz. A prototype is shown in photo 2. In the receiver circuit of figure 4, potentiometer Rl sets the frequency of the VCO, which is twice that of the capture frequency (the center fre- quency of the incoming modulated carrier signal). With the external oscillator-control components shown, this circuit can detect carrier frequen- cies from 20 kHz to 70 kHz. The rest of the components, however, are op- timized for 40-kHz operation. The photodiode I suggest is a type TIL413, because it has a spherical lens that allows it to "see" over a wider angle, 44 April 1982 © BYTE Publications Inc r> 11L •—^OUTPUT Figure 4: Schematic diagram of a remote-control or communication circuit based on the SN76832AN. This circuit is set up for use at 40 kHz, although the voltage-controlled oscillator can he adjusted from 20 kHz to 70 kHz. Any voltage from +S V to +18 V may power the circuit. thus enhancing the effective sensitivi- ty. In a pinch other photodiodes such as the TIL100 may be used. The data output is permanently en- abled in my design unless the external-output-enable line is brought to ground potential by external means. The output signal is buffered and level-shifted through transistors Ql and Q2 to provide a TTL- (tran- sistor-transistor logic) compatible output. The circuit runs at any volt- age between + 8 V (volts) and +18 V. I run it at +12 V. When the circuit "sees" a 40-kHz- modulated infrared light beam, the output goes to a normally high state, and the indicator light (LED1) comes on. The output then changes state in accordance with the demodulated data, exactly duplicating the sequence of the logic levels of the input signal that was fed into the infrared transmitter. Photo 3: Prototype of the infrared transmitter assembly, internal view. Photo 4: The assembled infrared remote-control/ com- munication system. On the left is the infrared receiver; the transmitter is to the right. The TIL413 photodiode is the small projection to the right of center of the receiver's front panel; the small projection on the left is a visible red LED that lights when the infrared carrier is detected. April 1982 © BYTE Publications Inc 45 Number IC1 IC2 C3 0.1/iF R13 EXTERNAL r-^^!^. DATA INPUT LJ>— ^W^" Figure 5: Schematic diagram of a handheld infrared remote-control transmitter. Four pushbutton switches actuate a NAND gate wired as an oscillator; different frequencies may be selected for testing or in communicating simple command functions. Two high- power infrared and one visible indicator light-emitting diodes are modulated at a carrier frequency of 40 kHz; control signals are sent as a simple on/ off modulation of the 40-kHz-modulated light beam. FREQUENCY ADJUST 10K — »$/€— +9V T — " — ^ — rft Figure 6: A simple circuit that provides only a 40-kHz carrier modulation for an infrared beam. This may be used for sim- ple beam-breaking intrusion-detection schemes. A Matching Transmitter After building and testing the receiver section, I argued with myself about an appropriate transmitter. The "hardware" side of me wanted to follow up on the inspiration that got me started on the project by using one of those complex encoder/decoder chip sets previously mentioned. The encoder chip would be built into the transmitter, and the decoder would be connected to the infrared-receiver circuit, providing parallel decoded outputs. The "software" side of me (I do have one!) argued that anything these chips could do in encoding and de- coding could be done by any fairly competent programmer in a few lines of code. The real challenge of the pro- ject was creating the infrared-light communication link, not encoding and decoding the signal. In the end, I decided that my inspir- ing vision was not worth the trouble, and I designed a relatively simple transmitter essentially consisting of a gated 40-kHz oscillator driving a pair of high-power infrared LEDs. As you can see in the schematic diagram of figure 5, jumper connections on the oscillator can be changed to allow modulation from an external signal source or to allow the communication link to be tested by your pushing one of the four pushbutton switches con- nected to the CD4011 NAND-gate component (ICl). The prototype transmitter circuitry is shown in photo 3 on page 45. The assembled transmitter and receiver are shown in photo 4 on the same page. 46 April 1982 © BYTE Publications Inc In the transmitter circuit, ICl is configured as a low-frequency oscillator. The four switches control the frequency of the oscillator. With the "1" button pressed, an 8-Hz, 50-percent-duty-cycle waveform is directed to the IR LEDs. Pressing "2" produces a 16-Hz waveform, pressing "4" produces a 32-Hz waveform, and pressing "8" produces a 64-Hz wave- form (the exact frequencies may vary somewhat). By pressing two or more of the buttons together, a total of 16 distinct frequencies can be created. System Testing and Use To test the transmitter and receiver, aim the transmitter's IR LEDs in the general direction of the receiver unit and press the buttons. The output signal from the receiver should be the frequency correspond- ing to the switch operated on the transmitter. The single-bit output of the receiver can be connected to any con- venient input line on your computer (such as a game-paddle input), and a simple program can be written to count and determine the frequency of the input signal. While much higher frequencies can be transmitted by this system, I chose these low, pulsed fre- quencies so that even a BASIC pro- gram could count the frequency. Nevertheless, if the frequencies are still too fast, simply substitute a higher capacitance for Cl in the transmitter circuit of figure 5 on page 46. The external modulation input of the transmitter is quite suitable for use in a wireless data link. Attach a serial output from your computer to the external data-input line, and con- nect the output of the receiver to another computer or to a remotely located printer. In fulfillment of my original plan, I decided to configure the transmitter in my infrared remote-control system as a hand-held actuator. If you simply want an infrared beam source for use as an intrusion detector in a security system, you don't have to build the entire data- transmission circuit; the simple Photo 5: The familiar BSR X-1Q hand- held control unit. This was built to work using ultrasonic pulses, but it can be modified to use infrared light. The added infrared LED can be seen on top of the housing. CUSTOM BSR IC PIN 7 40-kHz oscillator in figure 6 on page 46 will work nicely. TV-Set Controllers, Too After building the IR receiver and transmitter circuits described, I discovered that signals from any of the commercial TV-set remote-con- trol transmitters could be received just as easily as those from the transmitting device I had designed. Most set controls operate with car- riers in the 38-kHz to 41-kHz range. Of course, the data output that you get is a coded bit stream, generally 5 to 12 bits repeating every half second, but this should be no obstacle. While I haven't analyzed the coded TV-set-control data, they should be susceptible to differentiation by the same methods that worked for my simple frequency input. Perhaps you'd have to use a machine-language program to catch the fast data (about 25 milliseconds per word), but the results would be a professional- quality, very versatile remote inter- face to your computer. BSR Goes Infrared The remote-control transmitters for television sets are not the only means to an elegant remote-control CUSTOM BSR 3.9K IC PIN 15[> — VW- 3f)TIL39 33\*,^ ~ . Photo 6: Interior view of the modified BSR X-10 hand-held transmitter, modified according to figure 7. of the 40-kHz carrier will be marked by a high logic level coming out of the infrared receiver board for the dura- tion of the 40-kHz signal. The coded data is sent as a series of 1.2-ms and 4-rns bursts, representing logic and 1 respectively. The complete 13-bit message consists of a start bit (logic 1), 5 data bits corresponding to the key being pressed, 5 bits representing the logical inversion of the first 5 data bits, and 2 stop bits (logic 1). The binary codes and the transmission se- quence are shown graphically in figure 8 on page 49. I'm sorry I was halfway through writing this article before I thought to use the BSR X-10 controller. After the idea struck home, I took a pizza break. Then I came back to the Cir- cuit Cellar, added the modification of figure 7, and verified correct data reception using an oscilloscope . I haven't actually written the code to interpret the BSR controller's signals yet. But considering the well-docu- mented transmission protocol used in The longer the wave- length of its light, the higher the efficiency of an LED. the BSR, it may be easier to use this unit rather than figure out the unknown coding of a TV remote- control unit. In Conclusion Building a reliable infrared receiver has been a goal of mine for a long time. Many of my first designs did eventually work, but they couldn't be easily duplicated. Since I believe that many other experimenters are equally interested in IR communication and have experienced similar frustrations, I have arranged with Micromint to make available a complete kit of the infrared-communication circuits shown in figures 4 and 5. Included with these kits is a complete data sheet on the SN76832AN should you care to configure it for another fre- quency range. If you try infrared communication and are successful, you might develop applications for it that have previous- ly been ignored. Certainly experi- menters like myself have been look- ing for better types of man/machine interaction than presently exist. Until computer speech recognition becomes 48 April 1982 © BYTE Publications Inc / ^-START OF MESSAGE (LOGIC 1) r i D8 D4 D2 Di F D8 D4 D2 Dl F 11111(11111 minimi mm — «| 8ms [^ — EACH DIVISION IS 8ms D OR F I 40kH 2 LOGIC "1" 8 ms D OR F LOGIC "0" — *J 24ms \* — -40kHi 1.2 8ms D8- Figure 8: Timing diagram and binary command-code table used by the BSR X-10 Home Control System. CHANNEL NUMBER BINARY CODE OR FUNCTION D8 D4 D2 Dl F 1 1 1 2 1 1 1 1 3 1 4 1 1 5 6 1 7 1 I 8 1 1 9 1 1 10 1 1 1 11 1 12 1 1 13 14 1 o 15 1 16 1 1 ALL OFF ALL LIGHTS ON 1 ON 1 OFF 1 1 DIM 1 BRIGHT 1 1 practical, we shall have to be satisfied with pushing buttons to communicate with computers. But perhaps the in- frared transmitter and receiver in this article can make the connection a lit- tle more convenient. Next Month: It's been a long time since I wrote about time, time as measured by a computer's real-time clock. Next month, well look at plans for connecting a versatile clock to a per- sonal computer. ■ Editor's Note: Steve often refers to previous Circuit Cellar articles as reference material for each month's current article. Most of these past articles are available in reprint books -from BYTE Books, 70 Main St., Peterborough, NH 03458. Ciarcia's Circuit Cellar, Volume I covers articles that appeared in BYTE from September 1977 through November 1978. Ciar- cia's Circuit Cellar, Volume II contains articles from December 1978 through June 1980, Ciar- cia's Circuit Cellar, Volume III contains the ar- ticles that were published from July 1980 through December 1981. Parts Source The following is available from: The Micromint Inc. 917 Midway Woodmere, NY 11598 telephone (516) 374-6793 (for technical data) (800)645-3479 (orders only) Infrared Transmitter/ Receiver Kit $42 Includes two printed- circuit boards (one for the transmitter and one for the receiver) and all com- ponents shown in figures 4 and 5. Does not include the cases and power supplies shown in the pro- totype photos. Assembly manual and specification sheets provided. Please include $2 for delivery within the United States or $6 for foreign delivery. Residents of New York state please add 7% sales tax. References Ciarcia, Steve. "Computerize a Home," BYTE, January 1980, page 28. Ciarcia, Steve. "Self-Refreshing LED Graphics Display," BYTE, October 1979, page 58. Reprinted in Ciarcia's Circuit Cellar, Volume It. Peterborough, NH: BYTE Books, 1981, page 109. Cohen, Charles. "Blue-light LED joins red and green chip in package," Electronics, October 6, 1981, page 6E. Hewlett-Packard Optoelectronics Divi- sion — Applications Engineering Staff. Op- toelectronics Applications Manual. New York: McGraw-Hill Book Company, 1977. Seippel, Robert G. Optoelectronics. Engle- wood Cliffs, NJ: Prentice-Hall, 1981. Copyright 1 982 by Steven A. Ciarcia. AI! rights reserved. To receive a complete list of Ciarcia's Circuit Cellar project kits available from the Micromint, circle 100 on the reader-service inquiry card at the back of the magazine. April 1982 © BYTE Publications Inc 49 How to Use Color Displays Effectively A look at the elements of color vision and their implications for programmers Color is becoming an affordable option for personal computers, but like any new tool, it has special limitations and requirements. John Durrett and Judi Trezona Center for Automated Systems in Education (CASE) Southwest Texas State University San Marcos, Texas 78666 Walk into a computer store these days and you'll be blitzed by color: games with vividly colored objects moving amid colored textual instruc- tions'; graphs representing many rela- tionships at once, using a different color for each; and screens full of color-highlighted text. If you're a veteran of the black-and-white days of personal computing, you'll prob- ably feel like celebrating. After spending some time with one of those colorful systems, however, your eyes may give you quite a dif- ferent message. Where did those shadows on the screen come from? About the Authors John Durrett is a psychologist and the director of CASE, a research center for human factors in automation. Judi Trezona is a freelance writer based in New Braunfels, Texas. Why is the red fading in and out? Is that a purple enemy ship or a blue friendly ship? Your eyes will be telling you that something is wrong with the color; it actually seems to interfere with the presentation of information. Misuse Color vision is a complex process of three interacting variables: hue, brightness and saturation. of color is all too common in software designed to take advantage of this new small-computer capability. Like all new tools, color has its own special limitations and requirements, many of which are based on human physiology and psychology. Physiology of Color Vision The eye receives light in an area known as the retina. An extension of the brain, the retina is the most com- plex component of the eye. The light- sensitive cells within the retina are called rods and cones. Rods respond to low levels of illumination, produc- ing visual sensations of shades of gray but no color. They respond most to blue light and require about 30 minutes to totally adapt to changes in illumination brightness. Cones respond to high illumina- tion, producing visual sensations of color and detail. They require about 7 minutes to totally adapt to changes in illumination. Each cone is sensitive to red, green, or blue light; blue recep- tors are significantly less sensitive than are green and red. Near the retina's center is a slight depression called the fovea. Here, light has unobstructed access to the 50 April 1962 © BYTE Publications Inc *********** ****** *.*.*.*:* ****** ***** * * * * • * • • • • • ****** Photo 1: Green and yellow against a dark background can cause confusion by produc- ing the sensation of shadows and afterimages with color reversal. For a demonstration, stare at the center of the flag for 30 seconds, then look at a blank white surface. cones, which cover this area and are responsible for sharply detailed vi- sion. The number of cones gradually decreases from maximum concentra- tion at the fovea toward the edge of the retina, where the concentration of rods is greatest. Because a high con- centration of cones produces detailed visual experiences, the sharpness of an image decreases as the distance from the fovea increases. Besides determining sharpness, the retinal area receiving light affects color perception as well. In the fovea, the eye is sensitive to all colors, Mov- ing away from the fovea toward the edge of the retina, red and green become difficult to perceive. Even farther from the center, yellow and blue become difficult to perceive. At the extreme periphery of the retina, only black, white, and shades of gray are perceived. Current Theory The current theory of color percep- tion is based on an opponent-process mechanism. Three opponent recep- tions — blue/yellow, green/red, and white/black — produce color sensa- tion by increasing and decreasing neural firing rates. The theory em- phasizes adaption, contrast, color ap- pearances, and afterimages to explain color vision. For example, since it's impossible to see a mixture of red and green in the same patch of light, these sensations are explained as results of opposite and incompatible activity in the same system. The opponent-process theory has several implications for programmers setting up color displays. If the goal is to convey text or graphic informa- tion, opponent-color combinations should always be avoided. Yellow on a blue field and red on a green field produce the sensation of "shadows" on the display and afterimages with color reversal. This phenomenon is il- lustrated in photo 1. Certain other color combinations are undesirable because the colors tend to "vibrate" (imagine red on blue as an example). These characteristics and limita- tions of the visual system lead to the following recommendations about color display organization: • Since red and green areas of the col- or spectrum are reduced at the edge of the eye's visual field, don't use red and green outside the normal line of sight or place codes in these colors where they're likely to be overlooked. If they must be used at the periphery of the visual field, first get the user's attention by making the codes blink before beginning continuous display . • For best viewing on a black background, always code alphanu- merics in red, white, or yellow. • Limit blue to large nonfoveal areas (i.e., nonfocal); blue characters are more difficult to read than other characters. Psychophysical Factors Psychophysical factors also affect how we perceive color. Color vision is a complex process of three interact- ing variables: hue, brightness and saturation. Hue is what we normally think of as color (e.g., red and green are different hues). Brightness is related to the intensity of light reach- ing the retina. Generally, higher- intensity light sources appear brightly Guidelines for Using Color Effectively Select compatible color combina- tions. Avoid red/ green, blue /yellow, green/ blue, and red/ blue pairs. Use high color contrast for char- acter/background pairs. Highly saturated colors are generally limited on inexpensive color displays, so stay within the primary hues of red, blue and green. For casual users, limit the number of colors in one display to four. For ex- perienced, long-term users, up to seven colors may be used. Always code alphanumeric informa- tion in red, white, or yellow and con- fine light blue to large background areas. Since red and green are not easily visible at the periphery of the eye's visual field, code signals to be per- ceived in this area in white. Assign colors in ways that agree with the usual denotations. For exam- ple, use red for "stop" or "danger" and green for "go" or "all-clear." Incorporate shape as well as color when possible. This redundant coding improves communication and makes the system usable by color-blind indi- viduals. When fast responses are needed, use highly saturated red or blue prompts rather than yellow. If color coding has been used to teach relationships, use the same color coding when the individual is tested or expected to apply the learned relation- ships. As the number of colors increases, increase the size of the color-coded ob- jects. April 1982 © BYTE Publications Inc 51 Photo 2: Reduction in contrast lowers our ability to determine details, as illustrated in the various foreground and background color combinations. Photo 3a: Common denotations used incorrectly: green shouldn't be used to show deficit. Photo 3b: Common denotations used correctly to portray the same information. colored while lower-intensity light sources appear more dull. The retina, however, is also sensitive to dif- ferences among various wavelengths in the color spectrum. For instance, yellow is perceived as the brightest spectral color, while red and blue are perceived as the least bright. Saturation, which is produced by the interaction of hue and brightness, is diminished by adding white light. For example, a fully saturated spec- tral red becomes pink when you add white light. In terms of hue, it's still red, but a red of decreased saturation. Highly saturated colors are easiest to read. (Unfortunately, displays capable of producing saturated colors are among the most expensive.) Contrast is another variable that interacts with the physiological com- ponents of the human eye. While brightness is essentially a measure of the intensity of a light stimulus, con- trast is the relative brightness of signal over background. The greater the contrast, the better the readability of a display. In other words, darker colors (red or blue) are not as visible as light colors (white or yellow) when both are viewed on a dark back- ground. By using higher contrast, you produce more readable graphics. This phenomenon arises from charac- teristics of the human visual system. Lower contrast reduces our ability to determine details, as illustrated in the various foreground /background combinations presented in photo 2. Research has indicated that visual acuity depends on the size and color of a symbol as well as the type of background. In fact, symbol size must be increased as the number of colors increases. Another factor affecting display visibility is the environment in which a task is performed. Artificial or natural lighting in the work environ- ment can reduce foreground-to- background contrast. Too, sensitivity to color increases as the eye adapts to darkness. Improper lighting can re- sult in reduced performance, discom- fort, and fatigue in addition to limiting the effectiveness of color changes. Illumination surrounding a color-display task can have a signifi- cant effect on the time required to re- 52 April 1982 © BYTE Publications Inc RED GREEN GREEN RED BLUE ORANGE ORANG Photo 4: The words are easy to read, but try naming the colors! spond to the displayed information. Response times range from fastest for red and blue to slower for yellow and yellow-orange. When programming games and other interactive tasks, consider the user's environment. Remember that not all individuals have a perfect visual system. About 6 to 10 percent of the male population is color-blind, meaning that their eyes have defective color receptors and are unable to perceive certain colors. This factor affects less than .05 per- cent of the female population. Out of consideration for color-blind in- dividuals, programmers can code re- dundantly, i.e., use both color and shape for coding. For memory's sake, a limited number of color codes should be employed in most contexts. Users have recognized more than 50 colors with training, but the average user shouldn't be expected to remember more than 5 to 7 colors. This is the "magic number" usually associated with short-term memory (the memory you use to keep a telephone number in mind from the page to the dial). Novel displays should have no more than 4 colors, since this number is well below the average limit of short-term memory. This provides your brain with some memory space for other decision-making activities while the meaning of colors is being processed. Color also influences attention (where you are looking and what you are thinking about). By carefully us- ing color to manipulate attention, you can partition material at key points, organize it, and code or give meaning to it. Again, the number of colors used is important; having too many can interfere with the attention- gaining potential of color. You pay attention to the first flash of red, but by the tenth, it's routine. Our understanding of information can also be significantly affected by color. Material presented in color is generally processed faster than the same material presented in black-and- white. Apparently, color helps the computer operator organize work by directing his or her attention to what's important. No differences in the interpretation of information presented in either color or black- and-white are observed if adequate study time is allowed. Color can assist learning if used as a redundant cue or to highlight key concepts. However, the color coding of the concepts and responses must be matched for optimum performance. Common denotations of color should be considered when you plan color displays. For example, most people assume that red denotes "stop," "danger," or "down." Usual- ly, green indicates "go," "up," or "OK," and yellow means "caution," "slow," or "test." Any application of color to a specific task should employ these col- or denotations to achieve maximum performance. Graphics using red and green in ways contrary to accepted meanings interferes with information processing and can result in incorrect conclusions. Conversely, applying these two colors in agreement with their usual denotations actually assists information processing. For a clearer idea of this, compare photos 3a and 3b. Photo 4 illustrates the confusion that can result from improper color coding. Guidelines for the effective use of color in displays are summarized in the text box. Conclusions Color motivates. It gets attention. If applied with its limitations and re- quirements in mind, color can be a powerful manipulator of our atten- tion, memory, and understanding. ■ References LBorges, Marilyn A,, Stepnowsky, Mary A., Holt, Leland H. Recall and recognition words and pictures by adults and children. Bulletin of the Psychonomic Society. Feb- ruary 1977, vol 9(2), 133-144. 2.Cahi!l, Mary Carol and Carter, Robert C. Color code size for searching displays of different density. Human Factors. June 1976, vol 18(3), 273-280. 3. Christ, Richard E. Review and analysis of color coding research for visual displays. Human Factors, December 1975, vol 17(6), 542-570. 4. Durrett, H J. Color display systems: State of the art. Behavior Research Methods and Instrumentation. April 1979, 11. 5. Dwyer, Francis M. Color as an instruc- tional variable. AV Communication Review. Winter 1971, vol 19(4), 399-416. 6.EN0, Renee E. And Reutener, Donald B. Color context as a factor in encoding and as an organization device for retrieval of word lists. Journal of General Psychology. Ocotober 1978, vol 99(2), 223-232. 7. Farley, Frank H. and Grant, Alfred P. Arousal and cognition: Memory for color versus black-and-white multimedia presentation. Journal of Psychology. September 1976, vol 94(1), 147-150. 8.Katzman, Nathan and Nyenhuis, James. Color vs. black-and-white effects on learn- ing, opinion, and attention. AV Com- munication Review. Spring 1972, vol 20(1), 16-28. 9. Knoll, Neal E. Effects of irrelevant color changes on speed of name decisions. Quarterly Journal of Experimental Psychology. May 1977, vol 29(2), 277-281 . 10.Schontz, William D., Trumm, Gerald A., Williams, Leon G. Color coding for infor- mation location. Human Factors. June 1971, vol 13(3), 237-246. April 1982 © BYTE Publications Inc 53 CCE EVE Why this operating system? Ask the leading independent software vendors. They know- Intel s iRMX 86 well ■ enough to know it's an industry standard; that it allows them to plug into VLSI tech- nology, and to design in a heap of high-perform- ance features. Ask OEMs. They'll point out how it lets them tap a vast reservoir of mass- market application software. And how major software houses have already packed it with popular languages. And both will tell you that iRMX 86 s performance and cost advantages are flat out impressive. Which makes it a marv- elous match for the industry s most widely used VLSI microcomputers— the iAPX 86andiAPX88. N \\^ v> ^ ClO ^0^^^^ How marvelous? iRMX 86 has two to five times the multitasking talents of any other microcomputer operating system. So users can perform various chores simultaneously —with blazing, realtime system response. Thanks to ultra- fast context switching, task synchronization and memory-based message passing. And iRMX 86 even supports multi- processing. Not only overseeing our 8087 numeric processor and 8089 I/O processor, but going even further Often helping a whole team of 8086, 8088 microprocessors and 8087, 8089 processor extensions work together While you're reaping the rewards of multiprocessing performance— without PTED WHERE Company Microsoft Microfocus Digital Research Intel having to wrestle with multiprocessing software. Most importantly, iRMX 86 is the only operating system taking full advantage of VLSI— already putting its advanced archi- tectural virtues into silicon. A prime example being our iAPX 80130 operating system processor. It squeezes timing tasks, interrupt processing and key functions of the iRMX 86 nucleus all onto a chip. Marking the first major chapter in our commitment to bring operating software into silicon —so performance goes up as the cost goes down.. And when its time to tie into a com- munications network, you wont have to get tangled up writing complicated software: built-in software drivers are already in place. In fact, iRMX 86 is the only microcomputer operating system to support Ethernet^ the de facto standard for local area networks. The leading software vendors have added the most popular languages to iRMX 86. Incidentally, all these features are available for $130/unit in OEM quantities. Plus all are backed by extensive docu- mentation, development tools, workshops, field support, software main- tenance, and a company name that's liable to turn up anywhere. Who knows, maybe everywhere. For a free copy of our article "Choosing a Microcomputer Operating System, 11 contact your local distributor. Or write our Literature Department, 3065 Bowers Avenue, Santa Clara, CA 95051, (408) 987-8080. Language Available BASIC Interpreter BASIC Compiler COBOL CIS COBOL CBASIC FORTRAN Pascal PL/M Macroassembler iny delivers solutions Europe: Intel International, Brussels, Belgium, japan. Intel japan, Tokyo. United States and Canadian distributors: Alliance, Almac/Stroum, Arrow Electronics, Avnet Electronics, Component Specialties, Hamilton/ Avnet, Hamilton/Electro Sales, Harvey, Industrial Components, Pioneer, L,A. Varah, Wyle Distribution Group, Zentronics. Circle 211 on inquiry card. *Ethernet is a trademark of Xerox Corporation. A Human-Factors Case Study Based on the IBM Personal Computer Members of a human-factors evaluation team put the Personal Computer to the test. Robert G. Cooper Jr. Paul Thain Marston John Durrett Theron Stimmel Center for Automated Systems in Education (CASE) Southwest Texas State University San Marcos, TX 7S666 How user-friendly is the new IBM Personal Computer? How hard is it to learn to use? Will I get eyestrain from using it eight hours a day? Are the manuals complete, understandable, and easy to use? Does it operate effi- ciently for an experienced user? Are the error messages informative? These are some of the questions that a human-factors specialist would pose in evaluating any computer system. In this article we will use the IBM Per- sonal Computer as an example in evaluating human-factors issues in microcomputers. Microcomputers present a special challenge to the human-factors specialist because the group of operators is diverse and the machine is used for many different tasks. Thus, it's impossible to specify any single set of criteria by which to measure the computer's human- factors performance. We will examine here some of the features of the IBM Personal Com- puter that involve consideration of About the Authors The authors are psychologists at the Center for Automated Systems in Education (CASE) in San Marcos, Texas, human factors to illustrate that the set of criteria fluctuates. A complete human-factors evaluation of the Per- sonal Computer would be far too ex- tensive to present here. Our discus- sion should not be interpreted as either a complete or a representative assessment of the Personal Computer's overall quality from a human-factors perspective. We chose the IBM Personal Com- puter as an appropriate model for il- Expert users often un- cover new human- factors problems. lustrating the process of human- factors evaluation for two reasons. First, it is a new model and marks the entry into the microcomputer market by the largest computer manufac- turer. Thus, it has generated substan- tial interest. Second, because it is a new model, it will almost inevitably exhibit some human-factors flaws despite the best efforts of the designers and engineers. Evaluation Procedures Two kinds of information go into any human-factors evaluation: judgments made by human-factors specialists based on their knowledge of previous research and their ex- perience with similar systems and observations of users operating the system. The data collected often include: • types of errors made • frequency of different types of er- rors • frequency of consulting instruction manuals or seeking other kinds of aid • user comments about strengths and weaknesses of the system • user suggestions about needed addi- tions or changes to the system Most human-factors specialists prefer to draw conclusions based on em- pirical data collected from users of the specific system. However, because this way of evaluating a system is very time-consuming and expensive, most human-factors analyses, including those done at CASE, are based on a combination of the two methods. For the evaluation of the Personal Computer, we asked several types of users to operate the system. Some had experience on other systems, in- cluding substantial programming ex- 56 April 1982 © BYTE Publications Inc MORE COMPUTER POWER MINIMUM REAL ESTATE NOW! All ALSPA computers come standard a CORVUS** hard disk interface. In than 5 minutes you'll be up and running. In the space of a standard 8 inch drive, ALSPA com- puters have three RS-232, one parallel, and one hard disk port; 8 inch drives; and run CP/M software. Optional clock/ calendar. ALSPA per- formance starts at $1995, list. DEALER/ DISTRIBUTOR INQUIRIES INVITED Circle 22 on inquiry card. NTA CRUZ, CA 95060 • (408) 429-6000 *CP/M 'irfinrfflema k ajfjjl J TAL RESEARCH, IWC. *CQRVUgisI'trademark of CORVUS .SYSTEM&rtnc. Circle 176 on inquiry card. 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MOUNTAIN HARDWARE Rom plus — $1 19 Music System — $429.00 OK ID ATA M80 — $325 SL125 — $3150 M82A — $459 SL250 — $4200 M83 A — $729 M84 — $1 1 79 XEROX 820 -$2399 ZENITH Z19 — $669 289 — $2129 Arizona 1-602-246-1783 EXPOTEK CORPORATION 2231R W. Shangri La Rd. Phoenix, AZ 85029 perience. Some were adults— like many in the target market for the Per- sonal Computer — with little or no previous experience with computers. And some were children from age 10 to 14 with at least some experience programming microcomputers at home or in school. An important group missing from this set of users was individuals who have had extensive experience on the Personal Computer. People with ex- perience on a particular system often have the most informative comments. They often demonstrate that ap- parent problems can be minimized simply by changing the operating procedures. Because they are compe- tent enough to use the full set of features a system offers, they often uncover new human-factors prob- lems. However, because the Personal Computer is so new, we couldn't find such a group of users, and we didn't have the Personal Computer long enough at CASE to develop such a group. Also, because of limited time and resources we couldn't test using standard scientific methodology. Rather than following a carefully planned procedure, we made new procedures as we went along, re- sponding to insights from the test group. This type of evolutionary pro- cess normally occurs before an actual human-factors experiment is con- ducted. Then a consistent procedure is established so that all participants are asked to do the same set of tasks. Hardware Characteristics We will begin our examination of the Personal Computer by looking at some of the human-factors character- istics of the overall packaging. In its simplest form it consists of three units: the computer, the keyboard, and the display. For many applica- tions, it is irrelevant whether these three components are integrated or separate. For others, separate- component packaging is a decided ad- vantage because it offers flexibility in choosing a display or the option of locating the main unit with the disk drive away from potentially destruc- tive young hands (see also the discus- sion of the keyboard below). However, for a user who must move the system from place to place, the benefits of one-piece packaging may bias him or her toward an integrated system like the Superbrain or TRS-80 Model III. For a school system, the separate units are at least a complica- tion: three units rather than one must be anchored permanently to avoid ac- cidental damage or pilfering. A second characteristic, which has been the focus of substantial human- CASE . Researchers at the Center for Auto- mated Systems in Education (CASE) at Southwest Texas State University con- ducted the human-factors research on the IBM Personal Computer discussed in this article, The staff of CASE is engaged in teaching, research, and development in the area of the human- factors considerations associated with computer-based systems. Although much of the early work by CASE em- phasized human-factors issues in the use of computers in educational set- tings, recent projects, including work for Control Data Corporation (CDC), Comshare, and Polaroid, encompass a much broader range of human^factors issues in computer systems. The procedure at CASE is first to define the scope for a particular human-factors analysis. Once the issues are clarified, researchers collect data from previously published human-factors studies as well as more general psychological studies in the areas of perception, cognition, and learning. Occasionally, previous research is adequate, but more fre- quently it is used to further clarify issues and design the appropriate research study to answer the specific human^f actors issue being studied. In some ways the analysis of the IBM Personal Computer presented here is not characteristic of our usual research because no single task or user group is anticipated for the Personal Computer. As a result, researchers simulated a range of human-factors ex- periments that represent the kind of research which would be done in a full- scale human-factors analysis of a microcomputer. Thus, the general ap- proach and analysis presented here typify work conducted by groups like CASE on human-factors issues am problems in computer systems. I 58 April 1982 © BYTE Publications Inc T 1 [tj j POII I ; ZE/xS™ is a minicomputer AND a microcomputer. Through multiprocessor tech- nology, each user has a dedicated Z-80A-based single-board micro- computer module, housed in the system mainframe. But users enjoy minicomputer performance and capacity. Includ- ing modular hard disk storage of 34 to 600 megabytes. Tape backup. Shared printers with spooling and queuing. Disk caching. Access to a common database. Unequalled flexibility and reliability. The completely mod- ular, stackable system can expand to 64 users. To add a user, add only a dumb terminal and an inexpensive user microcomputer module. ZE/iS sounds powerful. Now prove it. Name Company Address City/ State /Zip Phone Trademarks ZE/aS, MUSE: OSM Computer Corporation Registered trademark: CP/M: Digital Research And ZE/xS isn't fazed by light- ning, voltage variations, or power failures. Power for the entire system is "buffered" through a battery/ recharger system that provides up to 20 minutes of operating power. Unequalled value. MUSE™ multiprocessor operating system is compatible with CP/M®. Minicom- puter performance and capacity. New levels of reliability and flex- ibility. All at a per-user price that is shockingly competitive. If the coupon isn't fast enough, call. OSM Computer Corporation 2364 Walsh Avenue Santa Clara, CA 95051 (408) 496-6910 TWX 910-338-2099 Circle 317 on inquiry card. BYTE April 1982 59 ?mmf m/Am The Aspen Software Company Spelling Checker. + QRAMMATlk Beyond Spelling Checking THE ONLY COMPLETE PROOFREADING PACKAGE FOR ALL CP/M, MS-DOS, AND TRS-80 WORD PROCESSORS We'll match Proofreader with any other spelling checker on the market. It has a big 38,000 word expandable dictionary, and can check even your largest documents in under four minutes. Proofreader looks up every word, and does not use less accurate root word analysis like some others. Full inter- active correction is standard on CP/M and TRS-80 Model 11 systems, and is a low cost option for the TRS-80 Model 1/ III. Spelling checking alone is not enough! No one else has anything like Grammatik! 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MS-DOS versions scheduled for March 1982 release. Proofreader Grammatik CP/M. MS-DOS $129.00 $149.00 TRS-80 Model II $99.00 $99.00 TRS-80 Mod. I/lII $54.00 $59.00 (Model l/III interactive correction option - $30.00) Trademarks: CP/M; Digital Research: TRS-80: Tandy Corp.; Proofreader. Grammatik: Aspen Software Co. A9Kea mtmmm ~\i , €m&$m P.O. Box 339-B. Tijeras, NM 87059 (505)281-1634 factors research, is the quality of the display. This of course depends large- ly on the monitor used. The IBM monochrome monitor, the only monitor supplied by IBM for the Per- sonal Computer, meets or exceeds all the standard criteria with respect to character size and clarity, screen brightness, freedom from flicker, etc. All the users we questioned were im- pressed by the display, even those who did not in general like green- phosphor screens. When evaluating a display for a large group of potential users (for example, for a school system), the criteria based on the results of published experiments are particularly useful because they were developed from data on a represen- tative sample of users. When an in- dividual evaluates a display for per- sonal use, experience with the display may be more useful than reading published results because the pub- lished criteria are more stringent than many people require. A third feature of the Personal Computer, on which a substantial amount of human-factors research exists, is the keyboard. Despite some of the advantages of alternate keyboard designs, it appears that American National Standards In- stitute (ANSI) standard and related keyboards (sometimes called QWERTY keyboards because of the first row of letters) will continue to dominate the field because of conver- sion and retraining expense. Therefore, we will examine the IBM keyboard from within these standard constraints. The keyboard "feel," the tactile sensation of typing on it, was highly praised by all who used it, particular- ly those who were familiar with other microcomputer keyboards. Frequent- ly mentioned virtues included the ability to move and change the angle of the keyboard, the sculpturing of the keys, and the keyboard's curved- plane surface. Hpwever, every user complained about the Enter and the left Shift keys (see photos la-lf). The Enter key is about Yi inch farther to the right than most users expected, and the left Shift key is about Vi inch farther to the right with the backslash key inserted between the Z and the Shift key. These unconventional loca- tions caused errors initially, but ex- tended practice usually eliminated such errors after about a week. Again, the importance of the key- board layout depends on the context in which the computer will be used. For occasional use by individuals who frequently type on other key- boards (e.g., by a secretary in an of- fice or by someone at home who does a substantial amount of typing at work), the keyboard layout may be a major annoyance. For the individual who types mostly on the IBM keyboard, it should be no problem. Also, if the use of the computer in- volves nontext materials, as in finan- cial planning or playing games, the layout may be less important than if the computer is needed for word pro- cessing. The inclusion of an extra key be- tween the Z and the left Shift key may become standard in the future. In Europe, many keyboards have this extra key to facilitate typing extra characters required in some languages. Some word processors in the U.S. are using this style keyboard to accommodate extra functions re- quired in word processing. So what is a potential human-factors problem today may be an asset in the future. However, on several Japanese key- boards, it is the right Shift key that is moved to allow the addition of an ex- tra key, illustrating that no standard exists for these additions. The keyboard of the NEC PC-8001 suggests one near-term solution. On this computer the user can select, with a single button, either an almost- ANSI-standard keyboard (with the right Shift key out of place) or a keyboard with the letters in alphabetical order (which is helpful for young children). This flexibility could be expanded to let users pro- gram the arrangement of their own keyboards. Documentation Human-factors considerations are especially significant in the area of documentation. Minimally, docu- mentation needs to fulfill three func- 60 April 1982 © BYTE Publications Inc /In d The Winner Is. By Four Users! ABC A'ig ^^^m^^fcT"— ■ — - Sfej^l'"^ Mm v*« ar /\ ^v sr % ^ F iimlrtiii When you are racing toward that finish line, beating the competition is everything. 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Join us in the winners circle with high performance equipment and the best dealer plan in the industry, Call or write: OUTSIDE THE USA WITHIN THE USA > Integrated Business Computers 21592 Marilla Street Chatsworth, CA 91311 (213)882-9007 TELEX NO. 215349 IBC/ DISTRIBUTION 4185 Harrison Blvd., Suite 301 Ogden, UTAH 84403 (801) 621-2294 Photos la-lf: Comparisons of keyboards. All have letters in the same position, hut note the variation in the placement of the Shift, Return, and other special symbols. Note also the various solutions to the problem of where to put all the keys not needed on ordinary typewriters. tions: initial training in using the system, quick reference for momen- tarily forgotten information, and complete documentation of capabil- ities and how to access them. Ideally, many other functions will be served, including guidance on uses for system features, information to aid in debug- ging (including common errors and their symptoms), etc. The manuals for the Personal Com- puter have received very high praise. Gregg Williams in "A Closer Look at the IBM Personal Computer" (January 1982 BYTE, page 36) wrote, 62 April 1982 © BYTE Publications Inc Your m computer. Compute. Compute. Compute. Compute. Compute. Compute. Compute. Compute. Compute. Compute. 1111 Yoiir printer New Microbuffer II lets you use your printer without tying up your computer. Time. As an important resource it shouldn't be wasted. One such waste is in printing, where your computer must wait for your printer. Now there's a way to eliminate this waste. Introducing the Microbuffer ][™, a buffered parallel printer interface for the Apple V computer with 16K characters of memory (user ex- pandable to 32K). It accepts data as fast as your computer can send it, allowing you to use your computer while the Microbuffer]! is in control of your printing. The Microbuffer ](, compatible with Applesoft, CP/M" and Pascal, comes with complete print formatting features as well as advanced graphics dump routines for most popular graphics printers. The Snapshot™ option per- mits you to dump the text screen or graphics picture to the printer while any program is /MICROBUFFER H running — without interuption. The 16K Microbuffer His available for $259. And the 32K version, for $299. The Snapshot option is $69. So why waste time while your computer waits for your printer? Ask your computer dealer for the Microbuffer]! or call us for the name of a dealer near you. hot are trademarks of Practical CP/M is a registered trademark of Digital Research, Inc. Apple I is a registered trademark of Apple Computer, PRACTICAL PERIPHERALS. Inc. 31245 La Baya Drive Westlake Village. California 91362 (213) 991-8200 "They will set the standard for all microcomputer documentation in the future." Our analysis of the manuals is less enthusiastic, although in many ways the documentation is excellent. We will take a look at the BASIC manual first to illustrate some of the strengths and weaknesses of the documentation. The manual is for reference and does not claim to be a programming tutorial. For its stated purpose the manual is quite good. All users who had prior knowledge of BASIC had no difficulty program- ming on the Personal Computer, in- cluding using some of the special features of IBM's version of BASIC. The features of the manual that are most useful are the index and the brief and extended descriptions of every command, statement, and function. The extended descriptions are most complete for those features that are unique to IBM's BASIC and include informative examples. There are five parts to each keyword description: format, ver- sion, purpose, remarks, and example. The only drawback is that some in- formation is omitted, apparently because it does not fall neatly into any of the categories. For example, restrictions and probable error messages from mistakes are only in- cluded in some of the descriptions. For the FOR and NEXT statements, information about errors is given in IBM has left the market for tutorial manuals to outside publishers. the body of the remarks section, and no information is given at all about restrictions on the amount of nesting or about overflow in nesting, which will lead to an "out of memory" er- ror. Despite these problems, the manual can be used effectively. As adequate as this manual is for the experienced user, it does not fill the need of the novice for an instruc- tion manual. General instruction manuals do exist (e.g., Basic BASIC and Advanced BASIC), but the idiosyncrasies of different BASICs have led to a demand for instruction manuals for individual machines. Ac- cording to our observations, novice IBM users had much greater difficulty with IBM's reference manual than do novices starting out on an Apple II Plus with Apple's instruction manual. IBM apparently made a conscious decision to leave the novice market to the independent producers of com- puter manuals and books. An IBM spokesperson assured us that such in- dependent sources are already hard at work and their manuals should be out shortly, but until such manuals are written, a hole remains in the documentation from the perspective of the computer novice. In the interim, IBM could make two simple additions to the current manual that would be helpful. One is a quick-reference card that could be removed from the manual; it would decrease the need to flip back and Allenbach Industries is putting tomorrow on disks. The future of the world is written in software. And Allenbach disk duplication is making sure that the future is faithfully reproduced. We use our own Allenbach diskettes and state of the art equipment with electronic surface evaluation of each diskette before use. Copies are 100% verified, track by track, and checked for readability on the appropriate computer. For information and prices, please call (800) 854-1515. In California, call (714) 438-2258 collect. 64 April 1982 © BYTE Publications Inc Circle 15 on inquiry card. JM •**£ --"* .» *- ...-♦■*■■ * - » r • - r* \ x _ •' * * v <*' ^H SYSTEM BUILDERS: THINK SOLID. THINK PRICE. THINK CCS. Each month, CCS produces, tests, and ships over 3,000 board-level building blocks. About ten come back for repair. And we're working on that. Built like a commodity. 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California Computer Systems, Inc. 250 Caribbean Drive Sunnyvale, CA 94086 408 734 5811 Telex 171959 CCS SUVL Circle 76 on inquiry card. forth from the brief- to extended- description sections of the manual. Second, a comment could be added to the preface about the existence of Ap- pendix D, which discusses the dif- ferences between IBM Personal Com- puter BASIC and other BASICs. None of our novice users discovered this appendix within the first hour of trying to learn to program in BASIC (we showed it to them after an hour), and such information would have been very useful in trying to use the general manuals for BASIC. Of course, these changes would be useful for more experienced users also. IBM's Guide to Operations presents a similar problem. It appears to be written for novices and contains 3 H :ie n *!itfc i ieutr~cis« r«l i this display on a Hf ** ?■ onitor. The AppI e' s tract tr line was 4«si9ft** (New items or new prices) CP/M users: specify disk systems and formats. Most formats available. DATA BASE FMS-80 $649/$45 dBASE II $595/$50 Condor II $899/$50 Access 80 Level 1 $249 Access 80 Level 2 $429 Access 80 Level 3 $679 WORD PROCESSING WordSearch $ 1 79/$50 SpellGuard $229/$25 VTS/80 $259/$65 Magic Wand $289/$45 Magic Spell $269/$25 Spell Binder $349/$45 Select $495/$na ** The Word $ 65/$na OTHER GOODIES Micro Plan $419/$na Plan 80 $269/$30 Target $189/$30 BSTAM $149/$na BSTMS $149/$na Tiny tr $ 89/$50 Tiny "C" Compiler $229/$50 Nevada Cobol $ 1 79/$25 MicroStat $224/$25 Vedit $130/$ 15 MmtModel $449/$50 StatPak $449/$40 Micro B+ $229/$20 Raid $224/$35 String/80 $ 84/$20 String/80 (source) $279/$na ISIS CP/M Utility $199/$50 Lynx $199/$20 v* Supervyz $ 95/$na INFO UNLIMITED® EasyWriter $199 Datadex $249 EasyMaifer $128 Other less 15% MICROSOFT® Softcard (Z-80 CP/M). . $298 Fortran $ 1 79 Cobol $499 Tasc $139 MICROPRO® Wordstar $269 MailMerge $ 99 Wordstar/MailMerge . $349 SuperSort I $159 Spellstar $129 PERSONAL SOFTWARE/ VISICORP® * Visicalc3.3 $225 •** Desktop/Plan II $225 ** Visiterm $ 90 "* Visidex $225 •* Visiplot $180 •* Visitrend/Visiplot $300 ** Visifile $225 PEACHTREE® G/L,A/R,A/P,Payor Inventory (each) $224/$40 OTHER GOODIES VU #3R (usew/Visicalc) $ 79 Context Connector (usew/Visicalc) $129 Micro Courier $219 Super-Text II $127 Data Factory $134 DB Master $184 DON T SAY UNCLE; SAY MICROTAX TODAY! Individual $ 250/$na Professional $1000/$na Partnership $ 750/$na Package $1500/$na ACRS, depreciation, batch computing/printing of over 30 forms /schedules, and much more. ORGANIC SOFTWARE* TextWriter HI $111/$25 DateBook II $269/$25 Milestone $269/$30 OSBORNE® General Ledger $ 59/S20 Acct Rec/Acct Pay. . , $ 59/$20 Payroll w/Cost $ 59/$20 All 3 $1?9/Sfi0 All 3+ CBASIC-2. . Enhanced Osborne PEACHTREE® General Ledger. . . Acct Receivable. . Acct Payable Payroll Inventory Surveyor Property Mgt CPA Client Write-up . .$199/$75 ... ,$269/$60 . . $399/$40 . $399/$40 . $399/$40 . $399/$40 . . $399/$40 $399/$40 . $799/$40 . $799/$40 Add $1?Q MagiCalc $269/$25 Other less 10% SOFTWARE WORKS® Adapt (CDOS to CP/M). $ 69/$na Ratfor $ 86/$na SOHO GROUP® MatchMaker $ 97/$20 Worksheet $177/$20 STRUCTURED SYSTEMS* Business Packages, Call for Price SORCIM® SuperCalc $269/$na Trans 86 $115 Act $157 TCS® GLorARorAPorPay $ 79/$25 All 4 $?fi9/$9Q Compiled each. . . . Inventory SUPERSOFT® Diagnostic I Diagnostic II Disk Doctor Forth (8080 or Z80) Fortran Fortran w/Ratfor . C Compiler Star Edit Other. . .$ 99/$25 . $ 99/$25 . .$ 49/$20 . .$ 84/$ 20 . .$ 84/$2Q . $149/$30 . $219/$30 . .$289/$35 . $174/$ 20 . $189/$30 less 1 0% UNICORN* Mince Scribble Both . $149/$25 . $149/$25 $249/$ 50 WHITESMITHS® 'C" Compiler Pascal (incl "C") PASCAL Pascal/MT+ Pkg... . Compiler Sp Prog . $600/$30 . $850/$45 . $429/$30 . $315 . $175 Pascal/Z Pascal/UCSD 4.0 . . Pascal/M . .$349/$30 . . $670/$ 50 . $355/$20 IBM PC SOFTWARE Business/Med/WP Call for Price ORDERS ONLY-CALL TOLL FREE VISA • MASTERCHARGE 1-800-854-2003 ext. 823 • Calif. 1-800-522-1500 ext. 823 Outside Continental U.S. -add $10 plus Air Parcel Post • Add $3.50 postage and handling per each item • California residents add 6% sales tax • Allow 2 weeks on checks, C.O.D. $3.00 extra • Prices subjectto change without notice. All items subject to availability • ®-Mfgs. Trademark. Blue Label $3.00 additional per item. THE DISCOUNT SOFTWARE GROUP 6520 Selma Ave. Suite 309 • Los Angeles, Ca. 90028 • (213) 837-5141 Int'l TELEX 499-0446 DISCSOFT LSA • USA TELEX 194-634 (Attn: 499-0446) TWX 910-321-3597 (Attn: 499-0446) without a long period of time in which to observe users trying to ac- complish this task. Also, an examina- tion of the individual features of the Personal Computer reveals that many of the best features from microcom- puters of other manufacturers have been incorporated. A separate ex- amination of each feature in terms of how it helps facilitate people's ability to use the system would start to sound like an IBM press release. However, the Personal Computer's versatility (in itself a human-factors asset) does entail human-factors costs. For example, many individuals have happily used their microcom- puter for years without being bothered by lack of precision or by rounding errors. On the other hand, the use of some computers for business bookkeeping is problematic because of limited precision. The IBM The error message appeared on the screen so briefly the operator never noticed. Personal Computer (and several others) offers the choice of single or double precision. This is an advan- tage to business users but requires a decision by other users ("Is 6~digit precision enough, or do I need 17?"). Some users may find that they prefer the old situation in which they obtain 9-digit precision (sufficient for home bookkeeping) automatically and do not have to make the determination. The system reset procedure on the Personal Computer provides a dif- ferent perspective on the problem of assessing human factors without a specific context. For purposes of com- parison, it is important to be aware of the human-factors problem with the system reset on the Apple II. On the Apple II, an operator would push the key labeled Reset, an extremely sim- ple procedure. Unfortunately it was too simple, and because the Reset key was directly above the Return key, it often occurred accidentally. Apple corrected this problem on the more recently produced versions by giving the user the option of choosing to re- 68 April 1982 © BYTE Publications Inc Circle 149 on inquiry card. iWCNTS FpLSO*?£0N MSRKfcT fO»C«ST-r*If3a6 is ntfu'ia 1 ill I »r .llllllullll How to chart your company's fortune without spending one It's a fact. A single chart or graph can tell you instantly what it takes hours to interpret from printouts or other raw data. Now, with the Strobe 100 Graphics Plotter and Software package, you can create superb hardcopy graphics directly from your computer. And you can do it for an investment of only $995. The Strobe System transforms complex data into dynamic, colorful visuals with a few simple commands from your computer. Charts and transparen- cies that once took hours to pro- duce are plotted within minutes. Information can be presented as bar charts, pie charts, curves or isometrics in a variety of colors. And with a resolution of 500 points per inch, the Strobe 100 matches or surpasses the quality of plotters costing thousands of dollars more. You can also save and modify your graphics through Strobe's menu-driven programs. A broad selection of software — including a VisiCalc* -compatible program — is now available. When the Strobe Graphics System is interfaced to your computer, an 8-1/2 x 11 inch sheet of paper can speak any- one's language — visually. Visit your local dealer and learn how to start charting your for- tunes today. Because a perspective on the present can also be your window on the future. " ^ Q STROBE X . .INCORPORATED^ Strobe Inc. 897- 5 A Independence Avenue Mountain View, CA 94043 Telephone 415/969-5130 The Strobe Graphics System Seeing is believing Circle 389 on inquiry card. * VisiCalc is a trademark of VisiCorp. quire a control key plus Reset for a reset to occur. On the Personal Computer, the operator initiates a system reset by holding down the Control and Alter- nate keys and then pressing the Delete key. This procedure is certainly cumbersome enough that it is unlike- ly to occur by chance. Is it too cumbersome? Because the operator uses three keys, none of which is labeled Reset, will the procedure be forgotten by those who need to use it? Without considering a specific con- text we can't answer these questions, but we can consider the kind of criteria a human-factors specialist would use in answering them for some particular context. First, how frequently is a system reset executed? If it occurs extremely rarely (as might be the case for someone using already developed software), it probably is all right if the command is forgotten and the user has to look it up. If it is used quite frequently (perhaps in debug- £Z* ging complex programs), it will be remembered because of the constant use. If it is used occasionally, it may be hard to remember and yet be frustrating to have to look up each time. Second, what are the conse- quences of making a mistake when trying to execute a system reset? If delay in a reset or if some combina- tion of related keys might lead to dire consequences in some application, then for that application the Personal Computer would have a major human-factors failing. Third, what alternatives are available and how do they interact with other human- factors characteristics of the system? For example, a separate key could be used as on the Apple II, but that either adds another key to the keyboard or takes up a key that might have been used for some other function. Too many keys produce an added memory load on the human operator, just as multi-keystroke commands do. The human factors trade-offs here must be evaluated in terms of the way the system will used. The Personal Computer has ten special-function keys called "soft keys," which have a set of default functions but can be changed by the user. The "soft keys" are a very popular characteristic among the ex- perienced users we questioned. However, because the keys can be redefined, they are labeled Fl through F10 — not very effective labels for remembering their functions. The Personal Computer solves this prob- lem by displaying partial labels at the bottom of the screen (for all 10 keys on an 80-column display and for the first 5 on a 40-column display). We expect that those operators using a television display (40 columns) and others not wanting the labels at the bottom of the screen will tape a list of the ten functions somewhere near the computer. In some ways it would have been nice if space had been left on the keyboard for labeling these keys. However, that would have had the undesirable effect of enlarging the keyboard. Again, there are always trade-offs. The relation of the line-editor pro- 70 April 1982 © BYTE Publications Inc Circle 416 on inquiry card. SANYO MONITORS When you're ready to stop playing around. Maybe your home TV was OK as a display when all you were concerned with was blasting Klingons. But if you spend more than I a couple of hours in front of your TV screen, you'll start to pay the price in eyestrain. Maybe even headaches. It's not worth it hot when you can get a 5anyo data moni- tor that's specifically designed for long-term, day-in, day-out use. Compare display quality of a typical home T\J (left) with a 5anyo professional monitor (right). 5anyo monitors have been the industry standard for as long as there's been a personal com- puter industry— in fact they're recommended by computer dealers and manufacturers alike. That's because when you buy a Sanyo, you're notjust getting a stripped-down TV set. You're getting a truly professional dis- play system. 5anyo offers a complete selection of monitors for any ap- plication. You can choose from 9" models with either white or easy-on-the-eyes green phosphors. Or a sleek new 12" model with a special anti-reflec- tive screen (green or white), and an optional desk stand with ad- justable tilt. If color graphics are your thing, check our 13" full- color models— one with TV- compatible video input, and a new ultra-high resolution RGB model for computers like the IBM, MEC and Apple III. Visit your computer dealer and find out how much better things look on a real, professional monitor from 5anyo. Anything less isjust playing around. © 1982 Sanyo Electric, Inc. Communications Products Division Sanyo Eiectric Inc., 1200 W. Artesia Blvd., Compton, CA 90220 (213) 537-5830 Circle 360 on inquiry card. 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A106- 1093 W.Broadway Vancouver, B.C. Canada V6H1E2 (604) 738-3500 gram that is part of the disk operating system (DOS) to some of the charac- teristics of BASIC is another human- factors issue. Using the line editor, for example, the Personal Computer lists lines 100 to 200 with a command of the form "100, 200 L" and deletes with a command of the form "100, 200 D". In BASIC, lines are listed with a command of the form "LIST 100-200" and deleted with a com- mand of the form "DELETE 100-200". The difference in syntax adds a memory burden for no intrinsic reason to anyone who uses both capabilities of the Personal Com- puter. An experienced user who was asked to use the line editor had trou- ble with the syntax. On the second day he used it he made errors and had to go to the manual to check the syntax of the commands. This syntax problem is a relatively minor issue when considering the line-editor pro- gram and BASIC but is representative of the more general class of dif- ferences in syntax that can lead to disastrous mistakes (not necessarily on the IBM machine). Perhaps the best example of syntax-function problems is that of commands for copying: on some systems the source is first and the destination second, whereas on others the reverse is true. Errors that were the product of mov- ing from one system to the other can and have resulted in the loss of crucial files. Conclusions We have illustrated the process of human-factors evaluation of microcomputers and its importance. Understanding that the user is part of the system is crucial to understanding the human-factors approach. Just as no single language is best for all pro- gramming, no single system design is best for all users. We have presented some general principles that apply to all systems but, for the most part, evaluations must take into account requirements of the specific, potential user. Groups like CASE, which per- form human-factors evaluation, start by determining the requirements of the user, then they evaluate the human-factors characteristics of the hardware, software, and documenta- tion in terms of those requirements. Because user needs vary so, it was almost certain that the IBM Personal Computer would have some human- factors failings; it could not be all things to all people. Although we did not attempt to perform a complete evaluation, our overall impression of the human-factors design of the Per- sonal Computer is very positive. IBM has begun to put substantial emphasis on human-factors design, and the IBM Personal Computer exhibits many positive results of the efforts of human-factors specialists. However, some of the simple and easily changed human-factors failings that we un- covered could have been detected from relatively simple observations of users. If you are considering purchasing a microcomputer, these comments have two major implications. First, be clear about the use or uses to which the system will be put, and then concentrate on human-factors characteristics that are relevant to those uses. Do not buy a computer that will be used primarily for word processing on the basis of the en- thusiastic recommendation from someone who uses his for home finance and playing games. Second, get as much information on the actual use of the system as possible. Use it yourself in the way you intend to use it; do not just go through a set of demonstration programs, even if they are designed to illustrate the features of the programs you will be using. Try to find someone who is already using the system in an application similar to the one you anticipate. As mentioned previously, we find ex- perienced users to be one of the best sources of human-factors insights. If you make use of the insights of others, you may avoid being the source of negative human-factors in- sights about your own system. ■ Acknowledgment BYTE would like to thank Computerland product manager Richard Mandel and the Austin, Texas, Computerland store for equip- ment and assistance provided during the preparation of this article. 72 April 1982 © BYTE Publications Inc Circle 248 on inquiry card. In an age when new standards are constantly emerging, one disk consistently meets or exceeds them all. Maxell.The Gold Standard. Not all disks are created equal. Some are better than others. To find out what's best for you, look for Maxell disks. They now carry the Gold Standard symbol of quality. It's your assurance Maxell disks meet or exceed every definition of quality. No matter who establishes it. 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Bank on it. maxell Maxell Computer Products Division, 60 Oxford Drive, Moonachie, N.J. 07074, 201-440-8020 STANDARD • 64K internal memory. • Up to 1.5 Megabytes of dual disk storage — easily expandable to 10 Megabytes. • Twin RS-232 serial ports. • A CP/Mf disk operating system. • Two 4 MHZ Z80A Processors for faster response. • A Full 80 x 24 line display on a 1 2 -inch non-glare screen. • Optional graphics capability. SUPE3BRAIN TM It used to be that buying a microcomputer was a simple task. There were only two or three manufacturers offering them and comparing prices and specifications was easy to do. Today, Intertec is no longer one of a handful of micro- computer vendors trying to attract your attention, but. . . we think we're still the best. And for a good reason. Consider pricing. Our customers tell us we're still the price/performance leader in single-user and multi-user micro- computer systems. Ask around. Most folks (and even some manufacturers) will concede that point. What a lot of people do not know is that Intertec may very well offer the best customer protection programs in the industry. What is customer protection? It's a totally new, comprehensive product and customer support program which virtually guarantees your long term satisfaction with every new Intertec product you buy. It means that if you are not satisfied with your Intertec purchase, you can get your money back at any time during the original factory warranty.* Or, in the unlikely event your equipment should become inoperative during the first few weeks of the warranty period, we will FEATURES • True multi-user capability— network up to 255 users. • Up to 1 .5 Million bytes of local, off-line user storage. • Four models of user workstations available. • 64 K Internal memory in each workstation. • A CP/Mf operating system. • 10—384 Megabytes of auxiliary disk storage. COMPUSTAR TM replace it for you! And we'll even provide a reimbursement allowance to cover your cost of returning the system to us. Go ahead. Review the pricing and performance specifi- cations of all the microcomputers available today. We think you'll agree with us. . . ours are still the best! If you want uncompromised performance, competitive pricing, sophisti- cated expandable products and just plain peace-of-mind, you'll want Intertec. Ask your dealer about Intertec's SuperBrain and CompuStar microcomputer systems. Or, call or write us at the iatered trademark of Digital Research, Inc. address below and get more information on today's values in single and multi-user microcomputer systems. SipiNTE^TEC =feSYSTEMS, 2300 Broad River Rd./Columbia, SC 29210 (803) 798-9 1G0/TWX: 810-666-2115 :ie 214 on inquiry card. Hardware Review The Hewlett-Packard Interface Loop — HPIL Unique Two-Wire System Allows Low-Cost Data Collection Robert Katz 248 East 90 St. #3B New York, NY 10028 The most intriguing feature of the Hewlett-Packard HP-41C has been the multiple plug-in port on the unit's back (see Steve Leibson's "The Input/ Output Primer, Part 3/' page 186). Until now, four ports have been available for plug-in RAMs, ROMs, a card reader, a ther- mal printer, and a bar-code reader. Yet users have been begging for the chance to let the HP-41C talk to the out- side world. Hewlett-Packard is very protective of its pro- ducts and does not publish specifications of the connec- tions to these ports. Justifiably, because the calculator's delicate CMOS (complementary metal-oxide semicon- ductor) circuitry can be damaged easily by improper con- nections. The public demands and Hewlett-Packard responds. By announcing the Hewlett-Packard Interface Loop (HP- IL), Hewlett-Packard has provided users with much more than they've been requesting. The HP-41C was a quan- tum leap beyond conventional calculators, and, remarkably, the HPIL is a quantum leap for the HP-41C. The Loop Hardware HPIL operation is powerful and sophisticated, but the hardware is simple, small, and easy to interconnect. A board called the HPIL Module (HP82160A) plugs into any of the four ports on the back of the HP-41C. The module receives its power from the HHC's internal bat- teries. Two 71-cm (28-inch), 2-wire cables extend from the module; at their ends are 2-pin male and female con- About the Author Robert Katz, who prefers to be called "Bob, " is a recording engineer for records, TV, and radio. He also dabbles in computers. At a Glance Name Hewlett-Packard Interface Loop (HPIL) Manufacturer Hewlett-Packard 1000 Northeast Circle Blvd. Corvallis, OR 97330 Price HP82I60A HPIL Module: $125, available now; HP82183 Extend- ed I/O ROM: price to be announced, available summer 1982; HP82I80A Extended Functions/Memory Module: S75, available now; HP82I81A Extended Memory Module: $75, available now; HP82I66 HPIL Converter: $395 for a prototyping kit including 2 converters, test board, HPIL cables and manual, or $ 1 250 in quan- tities of 10 with no accessories, available spring 1982; HP82182A Time Module: $75, available mid- 1982; HP82161A Digital Cassette Drive: $550, available now; HP82162A Thermal Printer/Plotter: $495, available now; HP3468A Programmable Digital Multimeter: $695 plus $ 125 for battery option, available now; HP82938A HPIL Interface Card for HP Series 80 Personal Computers: $295, available now; Description HPIL is a complete software and hardware system that turns the HP-41C handheld computer/calculator into a general-purpose, data collection, measurement, and analysis tool as well as an equip- ment controller. Other features Simple 2-wire connectors, "transparent" operating system Hardware options Digital Data Cassette, Thermal Printer/Plotter, Programmable Multimeter, GPIO Interface, Computer Interface, among others Audience Original equipment manufacturers (computer-aided manufacturing), instrumentation manufacturers, hobbyists, others 76 April 1982 © BYTE Publications Inc ^enjoy the problem-solving power of APL language on your Apple computer Solve engineering, scientific, or business problems easily-write finished applications software in a fraction of the time you'd take to write similar programs in BASIC, FORTRAN, or COBOL. . . and do it all with your Apple® right at your desk. Test your language against APL/V80™ To compare APL/V80's clear concise code with the language you're now using to solve problems, take this short programming test. Here are three common problems, showing the APL/VSO solution for each. Program your best effort for each problem in the language you use now. Now compare the number of lines and keystrokes needed to achieve a solution in your language to the APL solution. Keep in mind the APL/V80 solution shown contains not only the computation commands, but also every instruction needed to input required data , as well as all the commands to print out the results. Problem 1: Write a program to input a list of values (List "A"), sort the list from lowest to highest values, then print all the values in list A in ascending order. APL/V80 solution: Solution in your present language: ^Li/MIl] (Hint: Usually this takes two loops and 15 to 20 statements.) Problem 2: Write a program to input a list of values (List "X") and compute the standard deviation for the list values. APL/VSO solution: Solution in your present language: (( + /u-( + /n*fl)*2)*"i+ff«-p*«-a)*.5 ( Hint: Tnis * akes at least one lo °P and about 16 statements.) Problem 3: Write a program which will compress adjacent spaces to a single space, with possible multiple occurences, in a string of characters called TEXT. APL/V80 solution: Solution in your present language: (1, ("l + r)*l + T-t-' *=TEXT)/TEXT*-to ? Whether you're an engineer, scientist, educator, or businessman, now you can solve problems faster than ever using your Apple®. With APL/V80™ from Vanguard Systems Corporation, search for solutions in a fraction the time you thought possible. Get the added benefit of creating programs which are not only easier to write, but also are easier to under- stand, modify, and explain. Solve your problems faster APL/VSO™ is the most concise powerful program- ming language available for computer solutions to scientific and business problems on Apples (or CP/M®-based computers). When you have APL/V80, you can focus your attention moreon problem-solving, and concern yourself less with the details of program coding. APL/VSO lets you develop functional soft- ware, and debug it, in about one-fifth the time you need to program a solution in other languages. If you're an APL user already, you'll appreciate knowing we developed APL/V80 for the Apple with the ISO-ANSI proposed APL standard in mind. All future enhancements will be guided by developments in this standard, so APL/V80 programs maximize compatibility with other APL systems. More than a language: a new world of convenience APL/VSO is more than a language. . .it's a whole new world of convenience for you and your Apple. A variety of special features and auxiliary processors give you problem-solving power unmatched by any other language available for the Apple. Powerful auxiliary processors included The Graphics Processor gives you full access to Apple's high resolution graphics from APL. You can print to any ASCII device, including plotters, through arbitrary input and output modes. Our system vari- able quad-AV gives you all the characters any APL/ ASCII device can print, plus all 32 ASCII control characters, APL overstrikes, underlines, lower-case letters, and special control characters for full-screen applications. The Utility Processor gives you memory access and processor calls to both the 6502 and the Z80, so APL/VSO can access virtually any Apple system ROM or peripheral card. Our CP/M input File Processor lets APL/V80 read and work with any CP/M file. An Input Stack Processor lets you spool input commands for later execution. Our APL File Proces- sor gives you an indexed file system. The WSFNS workspace makes APL/VSO compatible with common functions from standard mainframe APL versions, plus some non-standard functions such as string- searching and extended formatting. Workspace FILE- FNS gives you the most commonly used facilities of file systems found on large timesharing services such as LP. Sharp and STSC. Make your Apple a wizard of a terminal Appropriate settings of APL/V80's system variable quad-TT, combined with your modem, let your Apple communicate with other computers. The APLTERM ■iiiliiiiiiiiiiiliiiiiiiiiilllllliiililiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiitiiiiiiiitiiiiiiiiiiiifiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiifl s Contact your local Apple dealer for a demonstration of APL/VSO and get your copy today. If you don't = have a local dealer, use this coupon to order direct from us now: Please rush the items ordered below. : I understand all items are normally in stock and available for immediate shipment: workspace goes even further, transforming your Apple into a wizard of an APL terminal. WSIS uses the workspace Interchange Standard format to transfer application workspaces in from or out to other APL systems. This gives you the power to move APL programs developed in one version of APL into another. Amazing APL power for your Apple If you already use some version of APL on a mainframe, a time-sharing service, or a minicomputer, you may wonder how useful APL/V80 can be in an Apple-size workspace. Our answer: you'll be amazed! To give you utmost memory availability, APL/V80's auxiliary processors occupy memory only when loaded. By using our )CSAVE and )CCOPY commands to move functions and variables into and out of a work- space, you can run applications far larger than your workspace. Also, APL/VSO makes auxiliary proces- sors you develop more powerful. By offering a variety of supervisory services, APL/V80 lets your AP's write error messages, read input, convert data, do string search and compare, or even halt processing upon error discovery. Minimum hardware required APL/V80 for the Apple requires a 48k Apple II with autostart ROM, or Apple II+, one disk drive, a Z-80 SoftCard, and either the Language Card, RamCard, or some other compatible 16k memory extension card. To learn more, act now No matter what problemsyou'resolving, APL/V80™ can help you solve them faster, more easily. If you'd like to know more, send us the coupon below. APL/V80 does so many things, in a single page we can hardly begin to tell all the ways it can help you. Write today for the full story of APL/V80 for your Apple. NOTE; Specifications subject to change without notice. Apple design, Apple II, Apple II+, and Lan- guage Card are trademarks of Apple Computer, Inc. CP/M is a trademark of Digital Research. SoftCard and RamCard are trademarks of Microsoft, More information about APL/V80 for Apple APL/V80™ User's Manual - Enclosed is $30. Complete APL/VSO - Apple Software Package Enclosed is $500. Please send me an end- user license, object code disk, documentation manual, and special APL character generator. Software PLUS RamCard - Enclosed is $675. Software PLUS Z-80 SoftCard - Enclosed is $850 5 Enclosed is my check for $ | OR Charge to: □ MasterCharge □ Visa = Ship to: Name 1 Address 1 City Card | Signature. Software PLUS Z-80 SoftCard PLUS RamCard Enclosed is $995 Complete Hardware - Software system - APL/ V80 - Apple Software PLUS Apple 11+ 48k computer with APL character generation card already installed PLUS Apple Disk Drive, PLUS NEC 12" video screen PLUS SoftCard PLUS RamCard. Enclosed is $3195. As above with second Disk Drive - Enclosed is $3695. date exp. .State, Phone . _Zip. VanguarcI Systems Coup. 6901 Blanco Road = San Antonio, TX 78216 § (512)3401978 = Circle 423 on inquiry card. A Day in the Life of an HP-41C / prefer to call my HP-41C an HHC. That way I don't have to call it a "calculator" or a "computer." Hewlett-Packard calls it both a "calculator" and a "system." Actually ; the versatile HP-41C can be treated any way the user desires. Its power and flex- ibility are illustrated by the following tour of the HP- 41C world. It's morning and I find no cash in my pockets. No, the HP-41C cannot mint money, but its continuous memory can tell me how much I have in my checking account. Upon pushing RCL (recall), the legend RCL appears in the alphanumeric liquid-crystal display. To the right, two prompts (cursors) can be seen; these prompts are the HHC's signal to supply a two-digit number in response. Since data register 9 contains the amount of my checking account balance, I punch and 9. The HP-41C answers with $127.59000. I only need to display two digits after the decimal, so I push SHIFT for secondary key functions, then FIX and 2. Each key gives a satisfying "thunk" when pressed; tactile feedback has always been a Hewlett- Packard feature. The display is even more helpful by naming each button's function as it is pushed. It's also easy to cancel or correct a function if a mistake is made. By using the back arrow key *-, the screen unambiguously shows each correction, and HP-41C error messages appear in English. I see that I have exactly $127.59 in my checking ac- count. Before deciding to deplete the account, I run downstairs to check the just-delivered mail and happi- ly discover the arrival of a check for $300. Pushing 3 STO + 09 adds the $300 to my checking account (at least within the calculator). In addition, I push E + and see the number 12, marking the twelfth deposit I have made since I began to count deposits in the Sigma registers. The Sigma registers can compute the mean (average) of all my deposits, the standard deviation, and other statistical functions. To find the mean, I push XEQ (for execute or run) and then spell out M-E-A-N. This ability to call a function by spelling out its name is very much a computer-like action. After stopping at the bank, I head for the recording studio where I work as an acoustical consultant and maintenance man. Arriving at the studio, I discover a volume unit (VU) meter that reads too low. I apply a sine wave to the recording console's input; 2.0 volts (V) are measured across the output terminals, yet the meter reads VU. Thanks to a program I've written, my HP-41C can talk to me in English and clue me in to the decibel error of the meter (see listings 1 and 2). I can call this program in two ways. One way is by name as above: XEQ d-B-V, and the program begins running. Since I use the dBV program a lot, I reduced the keystrokes to a single one via the USER mode. In USER mode, the HP-41C is customized for in- dividual use; programs or functions can be reassigned to any keys. The entire keyboard can even be recon- figured if desired, then returned to normal by a second push of the USER key. An added attraction is a keyboard overlay which allows you to identify reassigned keys with stick-on labels. Thus, a small, uncluttered keyboard can call literally hundreds of functions. Throughout the course of the morning, I will use several HP-41C functions and two other programs. When the job is done, I attach the HP-41C to one of many available accessories, a battery-powered ther- mal printer. With the aid of still another program, it prints out an invoice of parts and labor performed on this job. On the way to the next job, a friend and I play a game of Hangman on the HP-41C. This game is in- cluded in the Games Pac, which is designed to help while away those between-business hours. More serious Standard Module Pacs are available to help perform engineering and scientific tasks, among others. The average application module price is $35. The COPY function permits copying any program from ROM (read-only memory) to RAM (random- access read/ write memory) to allow customizing. For example, I have added personalized prompts to the game of Hangman. Listing 1: A single key depression in USER mode executes the author's program dBV. The calculator first prompts for a voltage entry; response is 2.0 V, and the RUN key is pressed. The calculator asks for reference voltage; 0.775 V is assumed if RUN is pressed. The answer is 8.2 dB over 0.775-V reference. Next, the program is run with a different reference voltage (1.23 V, which is 4 dB above a one-milliwatt reference across 600 ohms). The answer is 4.2 dB over 1.23 V. Another key depression in USER mode executes the author's program VOLTS. The calculator indicates that 1.55 V is 6 dB over 0.775 V. The display is formatted to two decimal places but can easily be changed. XEQ "dBV" VOLTS? 2.6 RUN REF?R/S=STND RUN 8.2 dB/0.3 V XEQ "dBV" VOLTS? 2.8 RUN REF?R/S=STND 1 . 23 RUN 4.2 dB/1.2 V XEQ "VOLTS" dB? 6.00 RUN REF?R/S=STND RUN 1.55 V/0.77 78 April 1982 © BYTE Publications Inc ft gamble with your «. Z • DUSUIGSS! * • $ ''Okay, which entry 4evel, sxngfe- user microcomputer should I own?" The BOS M System, "Which multi-user system should I own?" The BOS M System. "If I want a larger system with the ultimate in performance and capacity , what should 1 own?" The BOSMSystem Multiprocessor. "How much more does it cost to own a single-user set-up and upgrade it, than to start with a larger system?" Not a penny more. "Can I have diskette, tape, and large rigid disk storage?" Yes. "Hpw about really good accounting software?" TheMBSI* package (GL, AR, AP, PR, OE/INV, Sales Analysis — all in Cdbbl) is probably the best available on any system... this is one you have to see to believe . "How about Word Processing?" WordStar™, and others. "Can I run all the other software I've seen?" Yes, if it's GP/M* * * compatible, almost certainly! "Will I have to change the operating system when I expand?" No, with BOS/TURBODOS* * **, just upgrade ity "Well, this is important . . .will service be available when I need it?" Yes> with a large dealer network, strategically placed maintenance depots, and fast factory repair turn-around. "Sounds great! But isn't it too good to be true?" No., .and it's not even expensive! So, why take a chance with somebody else? "Okay, how can I get one?" Contact your dealer, systems house, or consultant — or call us toll-free! Dealer and OEM Inquiries Welcome Business Operating Systems, Inc. 2835 East Platte Avenue Colorado Springs, Colorado 80909 In Colorado Call: (303) 634-1541 Ton Free Number: 1-800-525-3898 Circle 63 on inquiry card. PPUCABLE INDUSTRY STANDARDS: S- 100 IEEE 696 • RS 232, HDLC/ SDLC, Async, Sync * CP/M* * * TURBODOS** " * 8" soft sectored diskettes ♦ ANSI X3/B5/15 Tape Cartridge *Micro Business Software, Inc. • ^Trademark of Micropro Int. Corp., San Rafael CA * * * 'Registered Trademark of Digital Research * * ** 'Software 2000, Inc. The powerful programming ability of the HP-41C is enabled by an extended version of the RPN language that Hewlett-Packard introduced to the public in 1971 with the world's first handheld scientific calculator, the HP-35. Over 130 scientific functions and 56 pro- grammable flags are available, some of which keep track of the status of peripheral devices as well as con- trol the peripheral's status. While all previously made calculators were hardware-intensive devices, the HP- 41 C is a software-intensive device. As such, each plug- Listing 2: A single key depression in USER mode executes the author's program PTOF (pitch to frequency). The calcu- lator asks for the note, and the operator responds with "B Flat/' one octave below middle C. The answer is 223 Hz; the note and its octave are also given. Next comes a printout of the first 22 steps of the PTOF program. Note the compact nature of the RPN code. Each line's interpretation follows: 01 — ALPHA Label; 02 and 03 — store loop control number in register 00; 04 and 05 — store ALPHA string in register 01; 06 —display format with no digits following the decimal; 07 through 09 — these steps display the PROMPT shown above; 10 — the operator's note is stored in the X register; 11— clear flag 22, the digit entry flag; 12 through 14— these steps display the second PROMPT shown in the running program; 15 through 17 — if flag 22 is clear, store in register Z. Other- wise, store the octave number there; 18 through 22 — some of the alphanumeric manipulations available to the HP-41C user. A complete listing of this program is available from Hewlett-Packard's Users' Library. Write to Hewlett-Packard, in module adds completely new functions, giving the HHC a new personality. Hewlett-Packard has taken a lot of care in naming functions so one can remember them easily, but if I forget the name of a function and don't have the in- struction manual handy, I'm not helpless. I can call up a CATALOG, a directory of the many functions available. Three such catalogs exist in the HP-41C (see listing 3). Usually this list is enough to jog my memory. The future of the HP-41C is virtually unlimited. If there were enough demand, a higher-level language such as FORTH or even BASIC could be implemented in a plug-in ROM. However, I find that the versatility of RPN eliminates the need of a higher-level language in most applications. A BASIC interpreter would run markedly slower than RPN. FORTH might be faster than BASIC, but the experienced user soon discovers that new functions can be added in a remarkably FORTH-like manner. Listing 3: A printout of the HP-41Cs CATALOG 1 function, which lists all user programs in RAM, including the number of bytes required. Total room used here is 1148 bytes. Ap- proximately 1064 bytes are free in the HP-41CV for more user programs, an astounding amount of storage ability for an HHC. Corvallis Division, 1000 Northeast Circle Blvd., Corvallis, CAT OR 97330 for information on how to join the Library. LBL'fO EHD 26B BYTES XEQ "PTOF" 07 "NOTE?" LBL 'PTOF NOTE? 08 RON EHD 283 BYTES BF 09 PROMPT LBL'dBV RUN 10 RSTO X LBL 1 VOLTS OCTfiVE?R/S=0 1 1 CF 22 LBL'dBH -1 RUN 12 "OCTAVE? LBL'HATTS 233 HZ, BF/- R/S=6" EHD 292 BYTES 1 13 OOFF LBL'Z PRP " " 14 PROMPT END 62 BYTES 15 FC?C 22 LBL'FREA 01+LBL "PTO 16 EHD 19 BYTES F" 17 STO Z LBL 'PAR 02 . 005 18 XEQ 05 LBL'RPAR 03 STO 00 19 RRCL Y EHD 37 BYTES 04 "CDEFGR" 20 RSTO Y LBL 'HANG 05 RSTO 01 21 RSHF EHD 262 BYTES 06 FIX 22 RSTO T .END. 33 BYTES Text continued from page 76 nectors. The cables are simple stranded wire; gauge is of little importance. Cable lengths can be up to 10 meters between devices when using simple stranded wire. Distances of up to 100 meters are possible with twisted, shielded, pair wire. Each HPIL peripheral (e.g., printer or data cassette) is equipped with two corresponding mating connectors. Extension cables are available from Hewlett- Packard. Plug the two loose cables into the side of the peripheral and you're ready to go. If there is more than one peripheral, connect the devices in a sort of daisy chain. In this loop, information passes from a sending device 80 April 1982 © BYTE Publications Inc Look What Apparat has for your IBM Personal Computer %rf^^ The following add-ons are available immediately: • 2 Dual Headed 40 Track Drives — (appears as four) 640K of storage, software patch, easy internal mount. $630.00 • Combo Card - Parallel printer, ASYNC communication (RS-232), and clock calendar functions, uses only one slot. $279.00 • 2 Single Headed 40 Track Drives - 320K of disk storage, easy internal mount. $450.00 • 48K additional RAM - 27 chips plug into master PC board $75.00 • Add-on Memory Card - (uses 64K dynamic RAM chips), 64K - $425.00, 128K - $525.00, 192K - $625.00, 256K - $725.00 • Prom Blaster — Programs most IK to 4K EPROMS of 25XX and 27XX single or multivoltage, personality modules, read/write software. $149.00 • Apparat Game Diskette - $24.95 • Clock Calendar - Features seconds, minutes, hours, day of week, date, month and year, backup battery, leap year and crystal time base. $129.00 • Prototype Card - 3.5 by 8 inch wirewrap holds 150-14 pin dips. $29.95 • RQB Color Monitors - Includes cable, 16 color modifications, MEC - $1,095.00, AMDEK - $899.00, TECO - $699.00. • 3rd and 4th Add-on Drives - Expansion cabinet and IBM compatible drives, cabinet and 1 drive - $499.00, two drives - $749.00 • 64K Hardware Print-Spooler - Parallel printer adapter, buffers 13 minutes of output at 80 characters/second. $399.00. • EPSOM MX Printers - MX-80 (with dot addressable graphics) — $499.00, MX-80 F/T - $575.00, MX-100 - $775.00 • Verbatim Datalife Diskettes - (5-1/4" 40 track, box of 10) $24.95 • 16K Memory Kits (9 chips) - $25.00 • 5-1/4" Flip-Sort - $21.95 • 5-174" Plastic Library Case - $1,95 Apparat will continue to develop add-on products for your IBM Personal Computer. Call today for more information. Dealer inquiries welcome. (303) 741-1778 IBM Personal Computer is a trademark of IBM. Apparatlnc. .— 440 1 So. Tamarac Parkway, Denver, CO 80237 (303) 74 1-1 778 TVY GOING SUPPORT FOR MICROCOMPUTERS' Circle 33 on inquiry card. W/izard-80 INSTANT 80 COLUMN APPLE The miracle of the 80's... 80-column card. STOP STARING AT 40 COLUMNS WIZARD-80 lets you see exactly what you will get when typing 80-column format. It gives you a full 80-column by 24-line display with ail these features. ■ Fully compatible with Apple II and Apple II Plus""* ■ Fully compatible with most word processors, micro-modems and prom programmers, plus all current Apple II expansion boards » Lists BASIC programs, integer and Applesoft ■ Fully compatible with Pascal ■ Uses software to switch between 40 and 80 column formats everything you want in an ■ Displays 7x9 matrix characters » Provides upper/lower case characters with full descenders ■ Fully edits . . . uses ESCape key for cursor movement • Scrolling stop/start uses standard Control-S entry Retains text on screen while it is being printed ■ Contains crystal clock for flicker-free character display ■ Has low power consumption for cool reliable operation ■ Leads soldered directly to board for maximum reliability ■ 2Kon-boardRAM,50or60Hz operation ■ Inverse video selection standard Available at all fine Computer Stores $295.00 ■OliiEsreii ii|ii;mi Si|sti:ms SUBSIDIARY OF WESPERCORP 'Registered trademarks of Apple Computer Inc. ■ Photo 1: The HPIL Module, Photo 2: HP-41C connected to an HPIL Module, Digital Cassette Drive, and Thermal Printer/ Plotter in the loop. \ J Figure 1: The HPIL is a continuous loop, with data and instruc- tions traveling from an originating device back to that device for a complete, bit-for-bit error check. through all the other devices. When data return to the source, they are completely checked for errors (see photos 1 and 2 as well as figure 1). Since each succeeding battery-operable device uses its own power to retransmit the data it receives, total power in the loop is shared equally, minimizing battery drain. All communication between devices is supervised by the HPIL Module, which is now available for $125. Circle 431 on inquiry card. HPIL Specifications: The New Firmware As mentioned earlier, plugging a ROM into the HP- 41C gives it a new personality. The HPIL Module is no exception. Within it are the routines essential for turning this portable, programmable calculator into a versatile "outside world" controller. Three types of HPIL routines are supported: printer-type operations (also suitable for video display and for controlling external devices); mass storage operations (for digital cassette or disk drive); and interface control operations (largely used for controlling external devices). The HP-41C as controller can address each device in the loop by a unique number. The HPIL Module is capable of addressing up to 30 devices in the loop, cer- tainly a quantity large enough to satisfy most users. If that's not enough, the addition of a module called the Ex- tended I/O (Input/Output) ROM will allow the HP-41C to extend its address capability to a total of 961 devices on the loop. If still more devices are needed, loops can be connected through an HPIL Converter. (Each loop, however, must have its own controller.) The Extended I/O ROM has additional capabilities which I'll discuss later. The calculator/controller designates which peripheral is to be a sending device (called a talker) because there can be only one talker at a time. The other devices on the loop become listeners. When so instructed, listeners can also act upon data passing through. For example, a printer can print information, a video display can display it, etc. Hewlett-Packard does not intend to publish the actual voltage levels or the digital nature of the commands used within the two-wire HPIL loop. It has revealed that the HPIL communicates with the outside world through the HPIL Converter, a general-purpose interface board designed to be attached to the user's GPIO (general- purpose input /output device) equipment. For example, an original equipment manufacturer (OEM) may wish to install an HPIL Converter within its electronic voltmeter, enabling the voltmeter to be programmed by an HP-41C or other computer. Hewlett-Packard intends to aid other manufacturers by providing all the details necessary for them to successfully communicate with the HPIL Con- verter. An overview of converter hardware connections will be presented in a later section. An Asynchronous Communication Loop Quite a few more essential details are known about the loop's protocol. The HPIL is an asynchronous com- munication loop whose speed self-adjusts to that of the slowest active device in the loop. For example, if a slow printer is connected within the loop but is not to be used, the controller can instruct the printer to ignore data/in- structions and pass them on to the next loop device. That way the loop can operate at its fastest possible speed. The Extended I/O ROM will even allow a means for the Digital Cassette Drive to pass data to the printer through an essentially inert HP-41C. In this mode, the HP-41C Circle 432 on inquiry card. WtzarJ-JGX 16K RAM APPLE MEMORY CARD Unleashes your Apple II* and Apple II Plus* computer. ON TO MAXIMUM MEMORY Wizard-16K gives your 48K Apple II or Apple II Plus the last bit of directly accessible add-on memory it can accept. And, it interfaces with all Z80** cards to give you CP/M*** ■ Fully compatible with Apple II and Apple II Plus ■ Adds 16K bytes of Random Access Memory (RAM) ■ Fully compatible with Z80 microprocessor cards for CP/M ■ Used with Z80 card, it turns your Apple II into a two- microprocessor system with 56K of usable memory ■ With a Z80 card, it lets you run BASIC-80****, COBOL-80**** F0RTRAN-8Q****, BASIC Compiler**** and Assembly Language Development System**** plus Applesoft BASIC*, Integer BASIC* Apple Pascal System* Apple FORTRAN* and Apple Pilot* Utilizes Apple DOS 3.3* 16-sector system to permit loading both Applesoft* and Integer BASIC* Compatible with VisiCalc***** Offers all features of Apple Language Card* (except Autostart ROM) Available at all fine Computer Stores $149.00 'Registered trademarks of Apple Computer Inc. •Registered trademark of Zilog "Registered trademark of Digital Research •Registered trademarks of Microsoft •Registered trademark of Personal Software ■Olin-srai ii|ii;iiu Hi|sti:ms is SUBSIDIARY OF WESPERCORP ^m will become a relay device rather than a controller and will not retard loop operation. HPIL Speed Just how fast is the HPIL loop? Depending on cir- cumstances, it can approach speeds of 40,000 bps (bits per second). While this is many times faster than most RS-232C serial links, the HPIL can be slower than the parallel-based IEEE-STD-488 bus. (Originally known as GPIB or HPIB for Hewlett-Packard Interface Bus, the present IEEE-STD-488 was developed by Hewlett- Packard.) The HPIL is intended to be a low -cost, non- competitive alternative to IEEE-STD-488. The HPIL is competition, however, for the more antiquated RS-232C. Just the fact that the HPIL uses only two wires gives it a definite advantage; then there is the availability of an HHC as a controller. Let's look at the speed of this asynchronous loop in more detail. Since instructions as well as data are sent around the loop, the instruction cycle of the controller may become a significant factor. In almost all cases, the loop controller will be the HP-41C portable calculator. While microcode (machine language) runs through the HP-41C at a speed of about 350 kHz, the practicalities of the Macro Instruction Interpreter effectively make an in- struction cycle much slower. An instruction such as ENTER!, originally keyed into program memory by the operator, takes about 40 ms to execute. This includes the overhead of the Instruction Interpreter and the HP-41C Operating System. Therefore, practical data throughput speed will probably average about 150 bytes per second (1200 bps). The 40,000-bps HPIL maximum could only be managed by, for example, an HP-80 series computer run- ning a machine-language controller program or by con- trollers Hewlett-Packard is now developing. Using the Loop Operation of the loop can be completely transparent to the user. When a printer is in the loop, the operator (or a running program) simply executes a PRINT function; the HPIL searches for the first available printer to perform the function using a unique feature called an accessory poll. Optionally, the operator (or a program) may specify a particular printer by means of the SELECT func- tion. In this case, the operator becomes only a little more involved with HPIL operation. Manufacturing plants may wish to have the HPIL con- trol a set of relays and read a number of indicators. The HP-41C is ideally suited to that task. Its alphanumeric capabilities and versatile keyboard allow programs to be written so that they can talk to the plant operators in plain English while performing complex underlying operations. Efficient firmware in the HPIL Module is available, allowing a user to perform READ /WRITE functions onto a mass storage device (such as the Hewlett-Packard Digital Cassette Drive) or PRINT functions. Firmware supports either the Hewlett-Packard printer or any ASCII-compatible standard printer having a parallel port. Using less efficient instruction methods, the present firmware also allows the HP-41C to query and change the status of relays, monitors, voltmeters, or hundreds of other devices. More Efficient I/O Operation The Extended Input/Output ROM plugs into the back of the calculator and will add the following functions to the firmware: • Extended addressing of up to 961 devices on the loop • User access to all additional functions involved with Terminal Patient. Avoid computer disasters with anti-static protective covers. Let's face it. Computer hardware can be subjected to many unex- pected ills,. . .dust, grime, spills, static, pets and more. Cover Craft Protective Covers are easily the best available. Our exclusive STAT-PRUF ,A anti- static vinyl prevents damaging static electricity. Double-fold stitching means unsurpassed life. Designed to precisely fit terminals, printers, drives, and more. Give your sensitive electronic equipment a fighting chance. Visit your local computer dealer or write to Cover Craft. Starting at $ 8.95 TM c COVER CRAFT CORPORA T t N ANTI-STATIC PRODUCTS PO. Box 555B, Amherst NH 03055 • (603)889-6811 84 April 1982 © BYTE Publications Inc Circle 129 on inquiry card. SXfea v* \ X* ** \lG ¥8. w x * * , . . describing the price performance leaders in table top computers. Owning an SX from IMS International is a joy no matter which model you choose. Both give you Winchester perform- ance and a lot more. Our 5000 SX table top computer features either a 5.5 or 11 MByte Winchester subsystem, plus one or two &Va" floppy drives. And our 8000 SX offers a 10, 20 or 40 megabyte Winchester, phis one or two 8" floppies, and a 17 megabyte incremental cartridge tape drive subsystem. Both high performance Winchester subsystems deliver awesome speed — ten times faster than floppies, on the average. You can load a 20 KByte system program in less than a second. More importantly, IMS systems are engineered for reliability, so downtime won't take away the gains Winchester technology brings. They're strictly business, from their metal-not-plastic cabinets to their test-don't-guess circuitry. And with our full 2-year warranty, you have it in writing. Software for the SXs includes either single user, or our new high performance multiuser/ multiprocessor operating sys- tems, plus BASIC, FORTRAN and COBOL languages, and a host of compatibility-tested application programs. For complete information and specifications on the 5000 SX and 8000 SX, along with the location of your nearby IMS International dealer, just contact us. We'll tell you everything you ever wanted to know about SX. Call (714) 978-6966 or (702) 883-7611 today, or write: INTERNATIONAL WE BUILD COMPUTERS AS IF YOUR BUSINESS DEPENDED ON THEM. 2800 Lockheed Way, Carson City, NV 89701 -Tfelex: 910-395-6051 Circle 203 on inquiry card. Listing 4: The DIRECTORY that leads every HP digital cassette. Owners of the Card Reader will be interested to know that file ALL is a WRITE ALL file containing the complete status of an HP-41CV. This file loads in about 25 seconds as opposed to the several minutes and inconvenience of using over 10 magnetic cards. More than 50 files of this size can be stored on one cassette! MR mtil TYPE REGS HEX PR 39 STATUS KE 1 TEST ST 18 fiLL HR 336 PTO PR 29 dBV PR 42 Z PR 9 control and query of external devices attached to the loop • A routine to enable bar-code generation on the new HP82162A Thermal Printer/Plotter • A routine to allow one or more cassette copies to be generated; especially valuable when distributing software or data for OEM use • An external device will be able to "call" the controller for service requests The HP82183 Extended I/O ROM will be available by the summer of 1982, with price to be announced. Extended Functions/Solid-State Mass Memory The HP82180A Extended Functions /Memory Module adds firmware as well as additional read /write memory to the HP-41C. While this new product is not directly in- volved with HPIL operations, it is being introduced now in an effort to make the HP-41C a more "friendly/' ver- satile controller and, of course, an even more powerful HHC. HP-41C owners not interested in controlling exter- nal devices can still make use of the Extended Func- tions/Memory Module. First, this device adds 47 new functions not included in the HP-41C mainframe. Second, the HP82180A and two companion Extended Memory Modules can increase the solid-state memory space of the calculator by 4.2K bytes to a whopping, handheld total of 6.2K bytes. Many users will look forward to a programmable ASSIGN function, which will enable special-purpose keys to be automatically assigned and later cancelled within specific programs. Previously, key assignments had to be executed manually. Note that the software- intensive design of the original HP-41C is what makes these post-production enhancements possible. Another extended function allows alphanumeric manipulations previously manageable but relatively cumbersome in the standard HP-41C. For example, the leftmost character of an alphabetic string can be iden- tified by a program and then acted upon. The 104-step program PTOF (partially described in listing 2) could be reduced to approximately 80 steps and would run faster with the new extended functions. Additional memory of 889 bytes is contained in the HP82180A; its companion, the HP82181A Extended Memory Module adds 1666 bytes. Two HP82181A units can be used at any one time. With all three modules plug- ged in, 4221 bytes of extended memory are available to the user. The additional 4.2K-byte memory is called ex- tended memory to distinguish it from the resident memory of the HP-41C. Extended memory is not online in the sense that programs can be executed directly or that data can be used directly. Instead, the new read/write memory is organized in a file and register for- mat, just as on a disk drive and with equivalent access speed. For example, two completely different specialized cal- culators could be kept in solid-state storage and down- loaded into the main RAM on demand. ASCII data of up to 4221 characters could be collected and stored in the field to be acted later on by the HHC, by a computer, or transferred to the new Digital Cassette Drive. It will not be necessary to "wipe" information in main RAM in order to move data from the extended memory to the Digital Cassette Drive. Data within the extended memory can also be sorted, alphabetized, or otherwise organized at disk-access speeds. The HP82180A Extended Func- tions/Memory Module is now available for $75, as is the HP82181A Extended Memory Module. Industry Reaction to the HPIL The HPIL is certainly a versatile system, but what's the catch? For now, there is one little catch: other manufac- turers may design peripherals to attach to the HPIL, but the only loop controller presently available is a Hewlett- Packard product. Therefore, a turnkey system would contain at least two Hewlett-Packard products — the HPIL Converter and an HPIL controller. The company says that the converter hardware will support controller operation. Unfortunately, the software to run a con- troller is very complex, causing concern over possible im- proper HPIL operation. Nevertheless, manufacturers who wish to develop a controller for the HPIL may con- tact Hewlett-Packard for details. Despite the Hewlett- Packard monopoly on the controller, the HPIL will pro- bably become popular with other manufacturers simply because the versatility of Hewlett-Packard's most power- ful calculator makes it the ultimate controller. HPIL Peripherals: The Digital Cassette Drive To me, the most intriguing new peripheral is the Digital Cassette Drive. Using digitally certified magnetic tape, it is truly a mass storage device (see photo 2). Up to 131,072 bytes of online mass storage will fit into a small cassette similar in size to an audio microcassette. The drive itself is compact, and its flip-top cover contains a convenient storage space for two cassettes. The magnetic storage is 50 times the size of the HP-41CV RAM and, ac- cording to Hewlett-Packard, contains enough mass memory to accommodate all the programs from the 26 HP-41 Solutions Books onto one tape. If this is not enough online capacity, HPIL firmware even allows "chaining" of multiple drives. 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Manual available at $25.00 each refundable with order. MACROTECH International Corp., 22133 Cohasset St., Canoga Park, California 91303 MACROTECH International Corp.. 22133 Cohasset St., Canoga Park, California 91303 Circle 244 on inquiry card. Photo 3: With the HP-41, HP82160A, HPIL Interface Module, HP-85, and HP82938A HPIL Interface Card, portable data col- lection, direct data transfer, and sophisticated data analysis are made easy. gram simply calls a file by its name. The HPIL firmware searches the directory at the head of each cassette until it finds the selected file, then loads the file from that drive into RAM. The cassette drive is of digital quality. It records data with parity, and a VERIFY function is available to check for errors. Being HPIL compatible, it can be addressed by controllers yet to be developed for the loop. Powered by rechargeable batteries, the drive has a standby power mode feature, especially valuable where operation on batteries and without human intervention is expected for long periods. The controller automatically calls a POWER UP function when it wishes to access the cassette drive. As a result, this unit is truly field operable. Using a two-track format, the cassette drive is bidirec- tional (one track per direction) with two speeds: 23 cen- timeters (9 inches) per second read /write speed and 76 centimeters (30 inches) per second search /rewind speed. For those concerned about potential head wear at these speeds, the company asserts that the tape-to-head pressure is so light that head wear is insignificant. Data density is 335 bits per centimeter. Format is 256 bytes per record, with 512 records available per cassette. When a file is called, the machine first reads the direc- tory at the head of the cassette for the location of the named file (see listing 4 for an example of a tape direc- tory). Then the cassette rapidly (76 cm/s) winds to the file and reads it back to the HPIL. Before writing a file, the machine looks through the directory to see if the name already exists. If so, it will rewrite (record over) that file. If not, and if space is available on the medium, it will add the new file name to the directory, speedily jump to the free spot on the tape, then record the new file, all under HPIL control. Seven different types of files may be recorded: Pro- gram, Data, Key Assignments, Status (condition of the HHC — useful for reestablishing conditions after a run- ning program has been interrupted), Writeall (entire con- tents of the calculator), ASCII, and Unknown. To check the effective speed of the cassette drive, I recorded and then read back a Writeall file (2352 bytes). I timed the machine from the moment I pressed the last key of the READALL command to the time the read was com- pleted. It took 27.5 seconds; therefore, effective average speed of data transfer using cassette is 85.5 bytes per sec- ond (684 bps). The read /write speed on the medium is a respectable 963 bytes per second, but, as you can see, tape-cuing time must lower the real speed considerably. The same amount of information could be loaded from a typical disk drive in a couple of seconds. New Thermal Printer Probably the most important feature of the new ther- mal printer is its HPIL capability, which allows it to be addressed by future controllers and computers. The HP82162A Printer/Plotter includes all the features of the earlier HP82143 as well as the ability to print bar code. Since it too runs on rechargeable batteries, a standby power mode is included. For those who are unfamiliar with the earlier printer, its features include: ASCII standard upper and lowercase characters and special characters, double-wide printing option, a 24-character line, user-definable characters, and plotting capabilities. HP-41C users should im- mediately see the potential of the HPIL interface plus printer plotting — an input signal can now be plotted in real time. More HPIL Peripherals The HP3468A Digital Multimeter (DMM) is program- mable through the HPIL. Its 12-character alphanumeric display can output messages generated by the controller or by the DMM. Resolution is adjustable from 3 to 5 digits, with increased resolution resulting in a propor- tional trade-off in speed. The HP82938A HPIL Interface Card shown in photo 3 plugs into the Hewlett-Packard Series 80 personal com- puter. The computer will then be able to take control of the loop. It can also be programmed to store and analyze data collected on the calculator. ROMs for the Series 80 machines are compatible with the HPIL Interface Card, allowing the computer to use the printer, cassette drive, and all future HPIL peripherals. The HP82182A Time Module plugs directly into the HP- 41C. This will allow the unit to be turned off and then "awakened" automatically by the timer's programmable ALARM function. The program will start running the line at which the HP-41C was positioned when it was turned off (or when it turned itself off). Since OFF is a programmable function, the process can be repeated in- definitely. The timer becomes especially useful in a con- troller situation, allowing measurements to be taken at regular intervals, devices to be turned off, pressures regulated, etc. This module can also display time and date and provide calendar data over a 2738-year span. The HPIL Converter The key to the HPIL's success will be the availability of 88 April 1982 © BYTE Publications Inc TAKE A 1 TEST DRIVE. ■ With a reliable TRAXX "100/200/300 F55* K ■ S I ^S5» ^ .. , ■■" , 1 !| V E^ E*23 gS33 ES23 Our drives feature excellent engineering; and all of the advanced performance features you've come to expect from the nation's leading disk drive manufacturers. All systems are completely burned-in and tested. And, you'll see at least five quality assurance stamps on each and every drive, which is how we make sure our drives will run and will continue to run past our optional two year extended warranty. Our drive packages start at $250.00 and in- clude a comprehensive operations manualand an attractive static free, dust free cover. Systems available for Altos, 1 Apple™, Atari, Heath™, North Star™, S-100, 2 TRS-8CF M (Model i, II, III, Color), Zenith™. If one of our drives fails to meet your highest expectations of how trouble free and reliable a disk drive can be, then return it to us for a complete refund.* So, before you buy another drive, take a test drive with one of ours. We're sure that you'll find TRAXX to be the finest. IT'S GUARANTEED! Circle 419 on inquiry card COMPUTER CORPORATION Call our toll-free TRAXX LINE: 1 -800-621 r31 02.. In Illinois, call: (312) 987-1024 10AM-6PM CST, Monday thru Friday. 'For full refund drives must be returned within 10 days of purchase. Photo 4: The HPIL Converter (4.5 by 11 by 2 cm) connects the HPIL loop with the outside world. the HPIL Converter. This component (see photo 4) is designed to interface the HPIL with the outside world, OEMs may wish to build HPIL capability into com- ponents such as measurement instruments, enabling pro- grammable control by an inexpensive HHC rather than a much more costly computer. BYTE readers who have connected hardware to com- puter input/output ports are probably familiar with a VIA (versatile interface adapter) or a PIA (peripheral in- terface adapter). Applying a similar philosophy, the HPIL Converter is a much smarter device. The converter contains the necessary firmware to recognize HPIL instructions and to convert specific instructions and data from the serial HPIL format to a dual 8-bit parallel for- mat. As a matter of fact, one of the sample schematics presented in the converter manual is an interface with a Centronics-style parallel printer connector. Hewlett-Packard supplies a 34-pin printed-circuit-type mating connector; a standard ribbon connector will also work. Power for the HPIL Converter ( + 5 V DC at 90 mA) is derived from the host device. All input/output lines are TTL-compatible and include two bidirectional 8-bit ports, three input handshake lines, three output handshake lines, and several special-purpose lines. The latter are used for triggering external devices and for communicating special conditions such as power down, power up, or service request. Complete hookup details for programming negative or positive logic strobes, full or half duplex operation, and more are furnished in the HPIL Converter documentation. Some Revisionist Thoughts The addition of all this hardware to the Hewlett- Packard arsenal poses a couple of logistical problems. The first problem concerns battery charging; there are too many plugs and not enough sockets. The HP-41C, printer, and cassette drive each come with identical-style power connectors. A power transformer and a charging cable are also furnished with each unit. It is certainly inconvenient to have to find wall sockets for all these devices. I hope that Hewlett-Packard relieves the conges- ts InfoWorld experts voted SPGLLGUARD H^\ I SOFTWARE PRODUCT III OF 1981" The Spelling Checker for Professionals FAST. Proofreads 40 pages a minute on a floppy disk. EASY TO USE, Beginners can use almost immediately. FLEXIBLE. Dictionary is expandable and technical dictionaries can be easily created. RELIABLE. Used daily by thousands and is guaranteed. COMPACT. 20,000 word dictionary uses only 53K. (jo Spellguard requires CP/M 'operating system and a word processing program. nnovATi 90 April 1982 © BYTE Publications Inc Circle 208 on inquiry card. A GALAXY of features makes the LNJ/V8t) a remarkable computer. As you explore the LNW80, you will find the most complete, powerful, ready to run, feature-packed per- sonal and business computer ever made into one compact* solid unit. QUALITY CONSTRUCTION - Instrumenta- tion quality construction sets LNW80 com- puters apart from all the rest. Integrated into the sleek solid steel case of the LNW80 is a professional 74-key expanded keyboard that includes a twelve key numeric keypad. HIG.H RESOLUTION GRAPHICS & COLOR- The stunning 480 X 1 92 resolution gives you total display control - in color or black and white. The choice of display formats is yours; any combination of eight colors. PERFORMANCE- Lift-off with. a 4MHzZ80A CPU for twice the performance. The LNW80 outperforms all computers in its class. MODEL I COMPATIBILITY - The LNW80 is fully hardware and software compatible with the Model I. Select from a universe of hardware accessories and software - from VisiCalc- to space games, your LNW80 will launch you into a new world of computing. • FULLY LOADED - A full payload includes &n on-board single and double density disk controller for 5 W' and 8" single or double sided disk drives. RS2-32C communications port cassette and parallel printer interfaces are 'standard features and ready to go. All memory is fully installed - 48K RAM, 16K graphics RAM and 12K ROM complete with Microsoft BASIC. Our down to earth price won't send you into LNW Research Corp. 2620 WALNUT Tustin, CA. 926 '14)641-8850 (I "* Monitor and Disk drives n©ftncluded TM Personal Software. Inc.* Circle 237 on inquiry card. Photo 5: Hewlett-Packard's HP82163A Video Interface connects a monitor or TV to HP's interface loop. This permits handheld computers like the HP-41C —previously limited by a single-line display— to display information in a 16-line by 32-character video format. Aided by the new interface (available by the end of 1982), HP-41C owners can review up to 16 program steps at a time. tion by introducing a charger capable of powering several peripherals at once. The second logistical problem is more serious. Hewlett- Packard has supplied a "horn of plenty" in modules, but there are only four sockets to receive them. A user may very well need to operate several of these modules simultaneously. Hopefully, the company will soon sup- ply a "piggyback module adapter" of some sort to relieve the problem. Outside of the above, very few complaints can be made about Hewlett-Packard's well-supported products. The Future With the introduction of the HPIL Loop, Hewlett- Packard has made a commitment to issue a series of new HPIL controllers, peripherals, and instruments. Expect to see in the near future a video/TV monitor interface (shown in photo 5), an 80-character/Iine impact printer, an HPIL/RS-232C converter, and a self-powered version of the GPIO board designed for the home hobbyist. No official corporate announcement has been made at this writing, but Hewlett-Packard probably will introduce these items before the end of the year. I'm sure someone will ask about word processing with the HP-41C and the HPIL. It's conceivable but not without an external keyboard since the HP-41C is only good for "hunt and peck" typing. Its alphanumeric capabilities and portability will lend themselves to many other unique jobs in the very near future. Conclusions As usual, Hewlett-Packard's documentation is ex- cellent. Prototypes of the new products must have been in use within the Corvallis, Oregon, plant for a con- siderable length of time because the style of the instruc- tion manuals reflects much experience with the products. With any new and complicated product, there are bound to be bugs. The ones I have found so far have been minor. My experience is that Hewlett-Packard's Corvallis Division will respond to consumer complaints quickly and efficiently. The potentials of the HPIL loop are literally awe- inspiring. As such, it is difficult for me to make an overall evaluation other than that the future looks bright. I sug- gest you read on to page 94 and delight in what's just over the HPIL horizon. ■ 92 April 1982 © BYTE Publications Inc ■ C-tnn cTQTir mcmhou QOEQi/Tuoni trtt tUU -fit ItIL I ILI tut 1 1 Ut ILI ttttttt tuuut t _/ '•• ••••• ••• ••• •••••• :u :::•*:; ::: :;: :::♦•• ••• ••* ••• ••• ••• •<__ lOfHiHirHHiirihlrr 5 tn su ::: su ::: ::: « *««— ••• ••• ••• ••• ••• ••• ••• ••• Hi Hi ::: :::: ••••••••• ••• — - , •••••* ••• • •• •••••< ::: ::: ::: ::: ::: ••• ••• •• «r ••• ••••*• ••• H:Sr*:H1:: .::::: •*• ••• ••• •••••• ••• ::::::: ••• ••• ••• ••• ••« ••• ••• ••• ::: ::: ::;.::: ::: ::: ::: ::: ••• ••• ••••• ••• ••• ••• ••• HUH Hi ::: ::: ::: ::: ::: ••••• ••• ••• •••♦• •::: ■• ••• ••• ••« 111 ••• »•••• ••*•• •••«•• ••• •••»••• •••••• •••••• ->•• ••• ••• ••• ••• ::: BE. :::.•. s::s:« ••:::;::••• ::: ::: ::: ::: ::: ::: ••••• •♦• ••• ♦•• ••• •••••• •••••• ••••• ••• ••• ••• ••• •••*• •••••• ••••* •• ••• •••••• ••• ••••••• ••••••• ••♦♦•• ••• ::: ::: ::: ::: ::: ::: ::; ::: ::: in in— ::: :ss ::: ::: s:s :::*•• ttt ••• ••• ••• •*• ••• ••• i m —m t^ . .■• ••• •*•*•* ••• ••••• ••• ••• •••••• ••• 16K STATIC RAM $169 64K STATIC RAM $795 32K PARTIALLY POPULATED $479 48K PARTIALLY POPULATED $659 Finally, you can buy state-of-the-art S-100 static memory for your computer at unprecedented savings. 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OEM and DEALER inquiries invited. a, memory fflfflff merchant Prices, 14666 Doolittle Drive San Leandro. CA 94577 (415) 483-1008 terms, specifications subject to change without notice. Circle 252 on inquiry card. 64K RAM, Model MM65K16S Cool running operation to 10 MHz Ultra low-power consumption Fully loaded 64K board draws: Typ. 350 Ma. (Max. current 550 Ma.) Bank Select Capability Extended Addressing Capability One 16K submodule equipped with a 2K window which may be located in any of the 2K segments 2716 (5V) EPROM Compatibility: Programmed 2716 EPROM's may replace any or all of the RAM Four independently addressable 16K submodules on one board organized as two pair of independent 32K banks or as one 64K Extended Address Page, Each 32K bank responds independently to phantom. Bank Select logic is compatible with either Cromemco Cromix* or standard Bank Select software. ♦Cromix is a trademark of Cromemco. New 16K (2K X 8) 150ns Static RAM Runs on any S-100, 8-bit system MPM Conversion Option: Write for details. 16K RAM, Model MM16K14 Bank Select Capability Extended Addressing Capability One 4K segment equipped with IK windows Four independent 4K X 8 byte segments Uses field proven 2114 (IK X 4) Low-power consumption (Typ. 1.3 Amps) Runs on any S-100 8080, 4 MHz Z-80 or 5 MHz 8085 system. The AI13 Interface puts your Apple* Computer to work in the Laboratory For Only $550 You can plug this powerful interface easily into your Apple Computer and create a fast, flexible analog data acquisition system with all these features: • 16 independent input channels • Ranges from lOOmV to ± 5V, selectable by software • 12 -bit precision, 0.024% accuracy • Fast 20- microsecond conversion time • Sample-and-hold circuitry captures changing signals • External trigger mode responds to commands from remote equipment • Software diskette included, to get you started right away A 1 13 comes with a 1 -year warranty and is backed by full technical support. It is part of a full line of IS analog and digital systems, all inexpensive and modularly designed so that you can select and pay for only the interfaces and functions you need. Interactive Structures has been designing and producing interfaces for Apple Computers since 1 977. Thousands of IS units are in use internationally. One is being used in the instrumentation for making analog readings aboard the NASA Space Shuttle. Write or call now for more information on the A I 1 3 — the best investment you'll make in a research assistant. •Recommended (J S list price each Apple is a registered trade name ot Apple'" 1 Computer Inc Circle 464 on inquiry card. Inc. Interactive Structures 112 Bala Avenue P.O. Box 404 Bala Cynwyd, PA 19004 (215)667-1713 A Future Day in the Life of an HP-41C It's morning (February 1, 1983), and I find no cash in my pockets. No, the HP-41C cannot mint money, but it can call the bank for me and engage in a friendly conversation with the bank's computer. I plug the Modem Management Pack into a blank slot and con- nect the HP-41C to an HPIL converter which in turn has been hooked up to a telephone coupler. I quickly learn that the check from Detroit finally cleared, a\ my checking account is good for $1000. Later, I arrive at the recording studio and discover a faulty VU meter (things haven't changed much). I am now carrying a powerful tool consisting of my trusty HP-41C attached to an HPIL Converter, an A/D (analog-to-digital) converter, and a long cable ter- minating in alligator clips. These components make up not just a programmable multimeter, but a complete measurement and analysis system customized by fi user — me! The HHC tells me that there is 2.0 V across the con sole's output terminals, which represents 4.2 dBs above the reference of 1.23 V. I suspect an intermittent connection, so I've programmed the HP-41C to beep whenever a change in level occurs (a high-frequency beep if the level goes up, low-frequency if it goes down) and to display the new voltage and dB level. When I wiggle a loose resistor on the circuit board, the HP-41C cheerfully beeps to signal the cause of the pro- blem. Even in 1983, cold solder joints and bad connec- tions cause the majority of service problems. My next job is rather distantly located, but this time the HP-41C is not available to play Hangman. It has a much more important job to do — it's helping to fly my Beechcraft. You see, back in 1981, the Hewlett- Packard company produced a custom ROM for the Beech Aircraft Corporation, turning the HP-41C into a revolutionary flight-planning system capable of saving thousands of gallons of fuel a year. Well, today (19841) this system has been updated so that the plane is equipped with an HPIL Converter. Since instrument data is now transmitted directly to the HP-41C, the pilot does not need to key in information about fuel flow, speed of descent, wind velocity, or air speed. Of course, as soon as I get the money, the next step will be to purchase the HP-41C Auto Pilot. By 1985, I will be able to plan my flight at home on the portable HP-41C, carry it with me to the airport, and plug it in- to the control panel of my airplane. Thus, it will help me in the air and continue to serve me on the ground. The preceding "science fiction" story is based entire- ly on components that are available today and on technology that is completely within reach. We have only begun to dream. I ELECTRONICS Electiohome Distributois Misumer Computer Mktg. Inc., Sudbury, Mass (617) 443-5128 Components Unlimited Inc., Lynchburg, VA (804) 237-6286 EMES Systems Ltd., New York, NY (800) 223-1799 Circ Anthem Systems Company, Burlingame, CA (415) 342-9182 Mycrosystems Distributors Inc., Dallas, Tbxas (214) 669-9370 Computerland, San Leandro, CA (800) 772-3545 (Ext. 118) Outside California (800) 227-1617 (Ext. 118) le 164 on inquiry ca TRS-80 DISCOUNT BUY DIRECT Q^3 C£?5 WE SELL THE FULL LINE OF TRS-80'S AT WHOLESALE PRICES *** PERSONAL COMPUTERS*** MICRO MANAGEMENT SYSTEMS TRS-80 MODEL II 26-4002 64K I Drive $3279 Ask About Hard Drives MODEL III 26-1062 I6K $819 26-1066 48K with 2 Drives, RS232 $2049 COLOR COMPUTER 26-3001 4K $309 26-3002 1 6K Ext. Basic $455 26-3003 32K Ext. Basic $569 POCKET COMPUTER 26-3501 Pocket Computer $ 1 55 COLOR COMPUTER DISK DRIVES 26-3022 Color Disk Drive #1 $498 26-3023 Color Disk Drive #2,3,4 $338 •LARGE INVENTORY WRITE FOR YOUR •FAST DELIVERY FREE CATALOG THOUSANDS OF SATISFIED CUSTOMERS ] ORDER TOLL FREE 1800-841-0860 MICRO MANAGEMENT SYSTEMS, INC. DEPT. NO. 1 1 15 C. SECOND AVE. S.W. CAIRO, GA. 31728 GA. 912-377-7120 TM TANDY CORPORATION FREE COPY OF WARRANTY UPON REQUEST Hardware Review Strawberry Tree's Dual Thermometer Card for the Apple Dr. William Murray RD #3, Box 363 Montrose, PA 18801 If you've ever needed to monitor temperatures over an extended period of time, then Strawberry Tree's Dual Thermometer Card is for your Apple. Actually, the card is part of a complete package that also contains a disk, two thermometer probes, and a user's manual. The thermometer card has an internal clock that can be set when the system is loaded, or, if a clock/calendar card is present in the system, the clock can be set automatically. This feature enables your Apple to record the time at which temperature data is taken. Data-sam- pling intervals can also be set to occur at any preset time by means of the internal timer. The current temperature, along with the maximum and minimum, can be recorded for each probe and stored on disk or sent to a printer as output. Everything in the package (see photo 1) is first class, which helps justify the retail price of $260. The card has fully socketed integrated circuits (ICs) and gold-plated edge connectors. The 83-page manual covers virtually every topic from installation to software modification. The software is a refreshing departure from many Apple peripherals on the market today. It is usable, under- standable, and can be modified if necessary. Photo 1: Strawberry Tree's complete package of temperature- monitoring equipment for the Apple. 96 April 1982 © BYTE Publications Inc Circle 265 on inquiry card. ■ THE $595* SMART TERMINAL The Heath 19 Smart Video Terminal gives you all the important professional features you want in a ter- minal, all for under $600.* You get the flexibility you need for high-speed data entry, editing, inquiry and transaction processing. It's designed to be the back- bone of your system with heavy-duty features that withstand the rigors of daily use. Standard RS-232C interfacing makes the 19 com- patible with DEC VT-52 and most computer systems. And with the 19, you get the friendly advice and expert service that makes Heath/Zenith a strong partner for you. Sold through Heathkit Electronic Centerst nationwide (see your white pages for locations). Stop in today for a demonstration of the Heath 19 Smart Video Termi- nal. If you can't get to a store, send for the latest Heathkit® Catalog. Write Heath Co., Dept. 052-894, Benton Harbor, Ml 49022. HEATH/ZENITH Your strong partner Completely ad- dressable blinking cursor lets you edit anywhere on screen. Reverse video by character lets you emphasize words, phrases or paragraphs. High resolution CRT gives you sharp, easy- to-read image, reduces eye-strain. Complete ASCII character set includ' ing uppercase, lower case with descenders, and special graphic symbols. 80 character by 24 line format, plus 25th line for operator mes- sages and prompts. Professional quality keyboard, standard type- writer layout, 72 keys, including 12 special function keys. Z-8G microprocessor- control makes the 19 capable of multitude of high-speed functions. It's the only terminal with ROM source code readily available. Insert and delete character or line plus erase to end of line and end of screen make the 19 ideal for sophisticated editors like WORD- STAR. Cursor and special functions are accessible by keyboard or computer, using either DEC VT-52 or ANSI Standard protocols. Keypad in calculator format permits fast, easy entry of numeric data. *In kit form, RO.B. Benton Harbor, Ml. Also available the completely assembled Zenith Z-19 at $895. Prices and specifications are subject to change without notice. t Heath Company and Veritechnology Electronics Corporation are wholly-owned subsidiaries of Zenith Radio Corporation. The Heathkit Electronic Centers are operated by Veritechnology Electronics Corporation. CP-202C At A Glance Name Dual Thermometer Card for the Apple 11 Use Long- and short-term temperature measurements Manufacturer Strawberry Tree Computers 949 Cascade Drive Sunnyvale, CA 94087 Price $260 Features Two temperature-sensing probes, Apple hardware board, software contained on a 5/4 -inch disk, user's manual Capabilities Reads present temperature of each probe, keeps track of maximum and minimum of each probe, and records temperature difference between probes. Also records date and time when samples are taken and sends data to printer or to disk for storage. Hardware required Apple II Plus with 48K bytes of memory or Apple U having 48K bytes of memory with Applesoft; disk drive with DOS 3.2, 3.21, or 3.3 (will load on 13- or 16-sector machines). Additional options Will output with no modifications to almost all printers that have been correctly interfaced; will set the date and time directly from a Mountain Hardware card; otherwise, the internal clock can be set from the keyboard. 1982 VERSION IFR SIMULATOR Apple II Plus DOS 3.3 Features a lifelike panel that simulates the airplane instruments that are used for flying and navigating in clouds. FLY IFR LANDINGS, PATTERNS, and CROSS COUNTRY in several areas of The United States. $50.00 at your computer store or direct from: PROGRAMMERS SOFTWARE 2110 N.2nd St. Cabot Arkansas 72023 (501) 843-2988 Hardware The thermometer card contains 12 ICs that draw 70 mA (milliamperes) from the +5-volt supply and 30 mA from the + 12-volt supply. If the need arises, up to 7 cards can be installed in an Apple II, permitting you to monitor 14 different temperatures. The probes come with 10 feet of wire but can be extended to 500 feet without loss of accuracy. The probes are electrically isolated from their 0.19-inch by 0.65-inch case but cannot be immersed in water or other conductive fluids. (Special probes are available upon request.) For noncritical applications, the probes could be enclosed in a boilable freezer bag. The accompanying loss in sensitivity wouldn't affect results where slow temperature changes are expected. The accu- racy of the unit is 0.4° from -20° to 50 °C and within 1° from -50° to -20° and 50° to 100°C. The thermometer card contains two major sections — a timer and an analog-to-digital converter. Its data- acquisition is similar to that used by the Apple's game paddles: resistance changes from the probes are used to alter the timing of a latch. The precision of the timing cir- cuit is much more accurate, however, than the Apple's simple circuit and is fully described in the user's manual. Because the system is set up to be slot independent, the card can be located anywhere (yes, even slot 0) without major modifications. External devices such as fans or heaters can be controlled using the data obtained from the dual thermometer board with the addition of the nec- essary interface hardware. This makes the device helpful not only for monitoring temperatures but also for controlling them. Software The software will load on 16- or 13-sector machines (DOS 3.3 or 3.2) without modification. When the disk is loaded, the time must be set from the keyboard if a clock /calendar is not available. This shouldn't be much of an inconvenience once the equipment is up and run- ning. The internal clock of the dual thermometer is trig- gered by the Apple's crystal-controlled clock, so accuracy shouldn't be a problem. The second thing that must be done upon starting the system is to set up the data-measuring parameters. The program gives you the ability to: • choose one or two probes for temperature measure- ment • monitor maximum and minimum temperatures of both probes • set alarms for temperatures above and below the preset maximum and minimums • record the difference between the two thermometers • specify output in Fahrenheit, Celsius, or absolute (Kelvin) • record data at predefined intervals on a printer or disk If the same setup is used frequently, it too can be recorded on disk, eliminating the necessity of entering the same information each time. 98 April 1982 © BYTE Publications Inc Circle 338 on inquiry card. ■ k f T A nJTTj ■ 1 J I lllllllllllllll! .* mm SEATTLE COMPUTER S NEW RAM+ GIVES YOU THE MEMORY YOU NEED AT A PRICE YOU CAN T FORGET. A great new machine, the IBM personal computer, just got better. With RAM+, the new expansion memory from Seattle Computer.™ RAM 4- can change your personal IBM from a pony to a workhorse by adding up to 256 K of memory. RAM + is expandable, reliable and is made by Seattle Computer, the people who created the operating system for the I BM personal computer. To make your IBM work even better, each RAM + card has a RS-232 serial port which uses IBM supplied software. And RAM + comes fully assembled, tested and with a 90 day guarantee* The RAM+ is available in 64 K, 1 28 K, 1 92 K or 256 K, with affordable prices ranging from $475. to $1,075. Expansion kits are also available. * Extended warranty available. How to order: Call Anna Ford at (206) 575-1830 for the location of the nearest RAM+ dealer. The RAM + —a great addition to your IBM personal computer. At a great price. Dealer inquiries welcome. &mfi TER 1114 Industry Drive, Seattle, Washington 98188 Circle 366 on inquiry card. (la) o o LU (X D < LU LV O 90 i \ r 1 x r— -i 1 \ 4 4 + 80 4 * 70 4 4 -t 60 4 4 + 50 4 + ■ 40 1 4 30 20 4 10 + -* * 4 1 + * Lower curve = Probe * Upper curve = Mercury Thermometer 12 3 4 5 6 7 8 9 10 11 12 13 14 TIME (MINUTES) (lb) 90 80 70 60 50 40 30 20 10 i ■ * * ■\ + + * * * Lower curve - Probe ' * 4 * *Upper curve =a Mercury Thermometer 1 2 3 4 5 6 7 8 9 10 11 12 13 14 TIME (MINUTES) Figure l:Tracking Strawberry Tree's thermometer probe versus a laboratory mercury thermometer. Figure la shows responses to an 8. 89°C/ minute rate of change; figure lb shows responses to a 4. 57 °C/ minute rate of change. One missing feature, however, is a method for obtain- ing an average temperature for the collected data. If desired, the software can be modified to accumulate the sum of all temperature samples taken and divide that sum by the total number of samples. This should be an easy modification since the disk is not "copy protected/' and the software is fully described in the user's manual. Limitations One of the major limitations of the Strawberry Tree Dual Thermometer card is the stabilizing time necessary for accurate measurements. The manual states that the probe requires 4 minutes to stabilize to within 0.1° for a 100° change. For comparison, a laboratory -grade mer- cury bulb thermometer will stabilize over the same temperature change in approximately 10 seconds. This would limit application of the device where large temperature variations can occur in relatively short time intervals. Appendix E of the user's manual addresses this issue and offers several suggestions for obtaining greater accu- racy. Figure 1 shows two experimental plots. Each plot contains two curves, one of the probe and one of a mer- cury bulb thermometer. In figure la, the average rate of change is 8.89 °C per minute, while that of figure lb is 4.57°C per minute. The rapid change in temperature with respect to time in figure la produces as much as a 4° error between probe and mercury thermometer. When the rate of change is slowed by a factor of 2, the two devices give about the same reading. This drawback won't be a prob- lem where temperature variations change slowly. In- deed, given the required stabilization time, I found the probes to be well within their rated accuracy. Applications The possible applications of this dual thermometer board are many because of the careful attention given to writing the software. With the ability to record data on a printer or disk, many long-term temperature studies can be undertaken. An engineer could use the dual-thermometer board in a solar heating experiment. One thermometer probe would monitor the internal temperature of the solar collector while the other would record the surrounding temperature. The data collected would help determine the best angle for the collector, the best collector coating for maximum heat gain, etc. With the card, readings for an entire day could be gathered automatically. A homeowner might want to do a long-term energy study by monitoring the temperature difference between the inside and outside of the house. After keeping track of temperature differences and the amount of oil, gas, or electricity used per month, the most efficient temperature setting for the house could be determined by plotting a curve of temperature difference versus fuel consumption. A scientist desiring to monitor the temperature of a microscopic culture might wish to record the information on a printer as it is gathered. A further possibility would be to have the computer sound an alarm if the culture got too hot or cold (this could be done by setting the alarms for the probe at the maximum and minimum limits). Conclusions The hardware and software of the Strawberry Tree Dual Thermometer board are excellent, with all opera- tions fully supported and documented. Any modifica- tions to the BASIC program should be straightforward and require only fundamental programming skills. The temperature probes can be located at distances up to 500 feet, offering great flexibility in probe placement. Special probes can be ordered for immersion in liquids. Two probes can be used at the same time, each recording its present temperature, maximum, minimum, and the temperature difference between the two. The software permits readings to be calibrated in Fahrenheit, Celsius, or Kelvin. Data can be recorded on a printer or disk at preset intervals. An alarm can be set for each probe to indicate when a preset maximum or minimum temperature has been passed. ■ 100 April 1982 © BYTE Publications Inc ERFILE, SOLVES YOUR FILING PROBLEMS SUPERFILE makes your information files an ASSET! CLIENT RECORDS Menu driven SALES LEADS CORRESPONDENCE JOURNAL ABSTRACTS Learn in minutes Customize PERSONNEL RECORDS Ready to run program MAILING LISTS Demo data base included CARD FILES LEGAL CONTRACTS ALMOST ANYTHING! included The USERS MANUAL tells you how to use SUPERFILE to index and retrieve information for these and other practical uses. IF YOU CAN TYPE, YOU CAN TEACH YOURSELF TO USE SUPERFILE IN MINUTES. You Need Computer with Z-80® cpu and at least 48K memory CP/M® operating system 2 or more floppy disk drives or hard disk Disk Formats 8" single density 5" including: Osborne, Xerox, North Star, Intertec, Apple (cp/m), Vector. Technical Specifications SEARCH SPEED: 100 records per second* RECORD ENTRY: your own text processor or easily convert your present files # RECORDS PER DATA BASE: max. 8,000 on 8" SD (depends on disk capacity) RECORD LENGTH: variable to 256,000 char. (free format - no fixed length fields) # KEY WORDS PER SEARCH: max. 64 using "and", "or" & "not" # KEY WORDS PER DATA BASE: max. 3,000 alpha-numeric plus 32,000 integers # KEY WORDS PER RECORD: max. 250 KEY WORD LENGTH: max. 64 char, each # FILES PER DATA BASE: no limit FILE SIZE: max. 256,000 bytes SORT: alpha-numeric by record MERGE and/or SPLIT: records and files Where Your Dealer Call FYI, INC. Write FYI, INC. Reader Service # SUPERFILE costs only $195 (including DEMO data base, manual and 30 day money back guarantee) MANUAL only: $50 (applies to purchase) Special Dealer DEMO free, on request from qualified Dealers and OEM's. SUPERFILE (TM) trademark of FYI, INC. Z-80* registered trademark of Zilog CP/M* registered trademark of Digital Research * Using Z-80, 4mhz, 8" DD, av. 10 keywords/record. Please add $10 outside the US, Canada, Mexico FYI, INC. P.O. BOX 10998 #615 AUSTIN, TX. 78766 (512) 258-6310 MC/VISA IT'S WHAT YOU CAN FIND THAT COUNTS! Circle 182 on inquiry card. Book Reviews Software Psychology: Human Factors In Computer and Information Systems Ben Shneiderman Winthrop Publishers Inc. Cambridge, MA, 1980 320 pages, hardcover $24.95 Reviewed by Bruce Robert Evans 16 Marwin Road Pickering Ontario Canada L1V2N7 Until recently, computers have been the domain of pro- fessionals. With the advent of personal computers, informa- tion networks, and dedicated controllers in equipment, programmers and designers must be aware of the impact of software on end users and vice versa. Much has been written about human engin- eering, but nothing has ap- peared about humanizing software. Software Psy- chology will help the systems engineer and programmer remedy this deficiency. The layout of the book re- flects the author's back- ground in the psychology of learning. At the beginning of each chapter, there is a list of the section headings, fol- lowed by an explanation of what is to come. Two sum- maries, one of practical points for the programmer and one of possible leads for the psychology researcher, follow the body of the book. The repetition distressed me, but with time it became obvious that it was achieving the desired purpose — I was re- taining the material. Shneiderman starts by analyzing what programmers do. Using one of the key tenets of management analysis, he delineates tasks and their performance. With- out generalizing, the author dissects some of the well- entrenched "truths." Do com- ments clarify a program? Do symbolic variable names help? Expect your prejudices to be challenged. The author insists on measuring as he at- tempts to assess a program- mer's output. Many com- monly held beliefs topple. For example, while the number of lines produced may be accept- able criterion for one pro- gram, the efficiency of style may be better in another. Chapters seven and eight, in which Shneiderman dis- cusses database systems, should be read by all pro- grammers. In them, the author explores possible sources of friction between programmers and nonprofes- sional users. Ways of dealing with irate nonprofessional users (Why is my credit card bill different from what I think it should be?) are dis- cussed. In chapter nine, Shneider- man discusses programming languages, emphasizing the at- tempts to create new lan- guages that will correct some of the faults of existing ones. (Does a month go by when someone doesn't come up with the "perfect language"?) The author stresses that because no one language covers all situations, pro- grammers should consider the advantages and disad- vantages of each when writ- ing for a nonprofessional. Chapter ten, "Interactive Interface Issues," justifies the entire book. In it, Shneider- man indicates the need for more study of the psycho- logic impact of computer pro- gramming on the end user. He discusses computer sys- tems from the user's point of view and points out user demands of which the pro- grammer may be completely unaware. In summary, Ben Shneider- man guides the systems engineer in deciding what a customer wants and needs, suggests how the software should be written, and assists in its evaluation. At the same time, the author shows the programmer what the soft- ware user wants and how the end user looks at a computer system. Often the user is very different psychologically and intellectually from the pro- grammer; the successful pro- grammer must be aware of this.B The Graphics Family. the most versatile, easiest-to-use graphics available for your Apple II. The A2-3D1/3D2 with A2-GE1 Graphics Editor package lets you put simultaneous multiple images on your screen . . . where you want, in the size you want, in your choice of orientation, complete with upper and lower case text. Because the most important part of your computer system is you. $119.85 ©tyfeUOGIC Communications Corp. 713 Edgebrook Drive Champaign, I L 61820 (217) 359-8482 Y I onftQCm Apple is the registered trademark of Apple Com 102 April 1982 © BYTE Publications Inc Circle 390 on inquiry card. I Start talking business with your Apple COBOL is the most effective business language. Apple II is the most friendly business computer. CIS COBOL with FORMS-2 brings together the best teatures of COBOL and Apple to enable you to deliver the most effective, user-friendly applications, Business Programmers: Take the COBOL expertise you have acquired on big business mainframes, and use it on Apple II to create friendly applications that will talk directly to your users - where it suits them best, on their own desks. CIS COBOL's dynamic module loading gives you big application capability and the FORMS-2 source generator lets you build and modify conversational programs from visual screen formats, creating much of the code automatically. Application vendors: CIS COBOL with FORMS-2 steps up the pace for your development of the high quality professional application packages needed today. And creating them in COBOL makes them more maintainable. Over half the Apple II 's now being sold are going to business or professional users so demand for quality applications is growing fast, creating big business opportunities for you. Stability proven by the US Government. CIS COBOL has been tested and approved for two consecutive years by the US General Services Administration as conforming to the ANSI 74 COBOL Standard. Apple II under CP/M is included in CIS COBOL's 1981 GSA Certificate of Validation (at Low-Intermediate Federal Standard plus Indexed l-O and Level 2 Inter-Program Communication). Get your hands on CIS COBOL at your Apple dealer. Talk business with him now! Micro Focus Inc., 1601 Civic Center Drive Santa Clara, CA 95050, Phone:(408)248-3982. H— <\ MICRO FOCUS CIS COBOL with FORMS-2 for use on the Apple II with CP/M is an Apple Distributed Product. CIS COBOL and FORMS-2 are trademarks of Micro Focus. CP/M is a trademark of Digital Research, Apple II is a trademark of Apple Computer. Circle 264 on inquiry card. ALL IT NEEDS IS THE PERSONAL COMPUTER CONNECTION FROM ,|l|e § NETWORK Sft?> DATA SYSTEMS. This printed circuit, small enough to fit inside the case of an IBM Model 50, 60, or 75 electronic typewriter, will interface with any RS232C computer system. The typewriter is still a type- writer, and an electronic com- munications system as well, with: • User-selectible baud rates • XON—XOFF protocol • Four parity options • Full or half duplex modes Yet for little more than the cost of the typewriter alone! For information call Network Data Systems of Fla., Inc. 1500 N.W. 62nd St., Suite 308 Fort Lauderdale. FL. 33309 (305) 772-9320 DEALER INQUIRIES INVITED Product Description The Epson HX-20 The First BYTE-sized Computer 104 April 1982 © BYTE Publications Inc Circle 298 on inquiry card. Gregg Williams Senior Editor Unfortunately, no monthly magazine can be complete- ly up to date on a given subject — some new product or idea always appears between the time we send the magazine to the printer and the day you see that same issue. However, we did get a chance to preview a product so exciting that we "stopped the presses" to get it into this issue. The Epson HX-20 microcomputer (see photo 1) is a remarkable unit that might be dubbed the first "notebook computer" — larger than a pocket computer and smaller than a briefcase computer, it is about the size of a notebook. It weighs in at 1.73 kilograms (3 pounds, 13 ounces) and measures 28.9 by 21.6 by 4.44 centimeters (11.375 by 8.5 by 1.75 inches)— somewhat lighter than but almost the same size as two issues of BYTE. The HX-20 has a full version of Microsoft BASIC, 16K bytes of memory, a standard-size and standard-configuration keyboard, a 24-character-per-line printer, a built-in cassette interface, and a 20-character by 4-line liquid- crystal display. The product will be officially announced at the National Computer Conference in June. Epson plans to have its distributors fully stocked with HX-20s by the time it is officially introduced. The unit was lent to us for a few days by Chris Rutkowski of Epson America Inc. Since this was a sneak preview of the HX-20, Chris told us some but not much about it. Most of the details below are a result of our physical inspection of the unit. For example, executing the BASIC statement "PRINT FRE(X)" produces the answer 12,832. This leads me to believe that the unit has 16K bytes of RAM (random-access read/write memory), Circle 239 on inquiry card. » Appje Logo has arrived * + » * the sophisticated yet simple to use language yoithave been reading about is now available for your Apple //.\ " Contact yoi/r Apple dearer today. WW 222 Brunswick Blvd. Pointe Claire, Que. Canada (514) 6£4-2885 CRtRegistered Trademark, Apple Computer Inc. computer *- systems inc. 989 Avenue of the Americas New York, N.Y. * U.S.A. (212) 564-6020 Product Description. ^^^^^H miHBHHI Photo 1: ^4 prototype of the HX-20 microcomputer. The final unit will have a different keyboard layout. Photo 2: The HX-20 printer and a printout of its character set. The Japanese katakana characters will be replaced in the U.S. version of the unit by geometric symbols that can be combined to make larger graphic images. Photo 3: The liquid-crystal display of the HX-20, which gives four rows of 20 characters each. 12,832 of which are free for BASIC programs and data. The unit we saw is a prototype of the final unit, which may be packaged somewhat differently and which will have a typewriter-style keyboard layout. Aside from the layout, the present keyboard is very good— it is stan- dard-sized (a very important feature if the computer is used for programming, word processing, data entry, or similar applications) and the keys have a good feel. The printer can display 24 characters per line, each in a 5 by 7 dot matrix (see photo 2). The LCD (liquid-crystal dis- play) provides four rows of 20 characters, each displayed within a 6 by 8 dot matrix (see photo 3). Both the printer and the LCD can show graphics, numbers, punctuation, and uppercase and lowercase letters. The LCD is ultimately 120 dots by 32 dots, each of which can be con- trolled by BASIC, Because Epson is a subsidiary of Seiko (the watchmakers), you might suspect the HX-20 to con- tain a clock; it does. The clock is accessed from BASIC by reading the variable TIME$. Setting the clock is just as easy. The cassette interface is said to transfer information at about 2400 bits per second (about 300 bytes per second) onto a standard dictating machine microcassette. This area of the unit appears to be detachable, which may in- dicate other storage options and/or telecommunication potential. The unit has several interesting sockets. The rear of the unit contains a socket for a power supply (the unit is estimated to run 50 to 100 hours on the internal nicad batteries), as well as two DIN sockets marked SERIAL (with holes for five pins) and RS-232C (with holes for seven pins). The left side contains a long, narrow, re- cessed plug containing two rows of 20 pins each (perhaps a system bus of some kind), and the right side contains plugs for an external cassette recorder, as well as a small phono jack marked BARCODE (which means that the unit is capable of reading bar codes). In addition, the right side of the unit contains a recessed Reset key and an on-off switch. (The unit, however, is never really "off"; this switch turns off the LCD display, but retains the pro- gram currently in memory.) Few details on the internal organization of the machine are yet available. It contains CMOS (complementary metal-oxide semiconductor) memory to keep the power consumption low. The HX-20 also uses the 6301 microprocessor, a CMOS version of the Motorola 6801 microprocessor. The price? Epson hadn't decided at the time this was written, but I was led to believe that it would be under $1000. I hope you are as tantalized by this information as I am. More information will be available after the unit is introduced at the NCC in June. Until then, it is enough to know that microcomputers are becoming more portable, more powerful, and cheaper at the same time, a trend that will probably not stop with the HX-20. ■ 106 April 1982 © BYTE Publications Inc ▲ 5-10-20 Megabytes in an add-on hard disk for IBM Personal Computer • Xerox 820 Apple • SuperBrain • Heath-Zenith TRS-80 Models II & III Targa, a truly high perfor- Targa 5 mance design, whether by Porsche or by CMC. Targa hard disk system, a signifi- cant extension to the stor- Targa 10 age capacity of your micro- computer, at an unheard of price/performance ratio. Suggested list for 5 mb: Targa 20 only $2895. 6.38 Mbytes unfor- matted, 5 MB for- matted. Upgrade- able to 10 MB 12.8 Mbytes unfor- matted, 10 MB for- matted. Upgrade- able to 20 MB for- matted 20 Mbytes format- ted, 25.6 MB un- formatted Our Targa Winchester-type, hard disk drives are offered in desk-top dimensions of 15" x 5 1 /4" x 13%*. It comes complete with ca- bles, software and interface. Call or write for complete specifications and/or the dealer nearest you. Dealer inquiries invited. Circle 86 on inquiry card. CMC INTERNATIONAL A Division of Computer Marketing Corporation 11058 Main • Suite 220 • Bel levue, WA 98004 • Phone (206) 453-9777 • Telex: 152556 SEATAC Call Toil-Free 1-800-426-2963 A Human-Factors Style Guide for Program Design Taking the user into account in the design of software. Henry Simpson Anacapa Sciences Inc. P.O. Drawer Q Santa Barbara, CA 93102 Human factors is a small but grow- ing discipline which seeks to provide a method for taking into account human strengths and limitations during the design of computer hard- ware and software. In this article, I'll present a brief introduction to human factors and discuss its application to program design. I'll define six human- factors design principles and show how they can be applied to three areas of program design: data entry, display-screen design, and sequence control. Human factors can be applied to any area in which a human being in- teracts with a machine. The discipline applies, or at least can and should be applied, to many aspects of man's in- teraction with computers. The most obvious area, and the one most people think of when considering human factors, is hardware design. Human-factors specialists often design video displays and controls. More recently, human factors has been applied to software design. Re- search has led to the development of human-factors guidelines that pro- grammers can use to make their pro- grams easier to use and less prone to error. Human factors is also impor- tant to the design of computer operat- ing systems, programming languages, and documentation, although the discipline has received less attention in those areas. Human factors matter because peo- ple must operate machines. If you fail to take people into account during de- sign, then your machine (or system or program) may be difficult or impossi- ble for people to operate. As obvious as it seems, this point is often over- looked. Consider some recent ex- amples. No brand names are men- tioned in what follows, but you may recognize some of the players: • The microcomputer whose non- standard keyboard made it awkward for touch-typists — all keys were there, but they were the wrong kind of keys and in the wrong locations. The more serious the error consequences, the more designers should consider human factors. (The keyboard has since been rede- signed.) • The minicomputer whose operat- ing system identifies program errors with numeric codes that are con- tained in three separate manuals. (This machine was recently discon- tinued.) • The computer program whose screen displays are cluttered and con- fusing, whose data-entry sequences permit input errors that cause the program to interrupt, whose menus can lead the operator down blind alleys and into stable program states from which he or she cannot escape. The documentation for this program consists of three smudged photo- copies of an original that displays creative spelling and grammar and omits many important details. We often blame human error for disasters and near disasters, from nuclear near-meltdowns to bank errors in checking account balances. Equally often, we blame "the com- puter" for some ill fate that befalls us. Seldom do we recognize that neither man nor machine alone is completely responsible. In today's complex world, man and machine work to- gether interactively. The "system" is the combination of both. When we design things, it is usually fairly easy for us technically oriented people to take into account the limita- tions of our hardware. However, we are likely to forget that the operator or maintainer of our system has limitations. We can design much better systems — more workable and more maintainable — if we accurately take human limitations into account. What are human limitations? First and most obvious, no two human be- 108 April 1982 © BYTE Publications Inc ■HIH ■^^■H^^^BH^^HI^^HI^H i^^^HI Qantex Impact Printers 1 50 Characters Per Second 1 36 Columns Per Line The microprocessor controlled Series 6000 is packed with standard features. True lower case descenders and underlining. Bidirectional logic seeking. Built-in test capability. Rugged 400 million character print head. Beautiful 96 character set in a 9x9 matrix. Parallel, or up to 19,200 baud serial interfaces supporting RS-232, X-ON, X-OFF or Current Loop. Full operator con- trols. Quietized, sleek enclosure to en- hance your system. Delivery from stock. QdnteX* Division of North Atlantic Industries 60 Plant Avenue, Hauppauge, N.Y. 11788 (516) 582-6060 TWX 510-227-9660 (800) 645-5292 For more information call your local distributor: ARKANSAS Hemco Electronics (501) ARIZONA The Phoenix Group Inc. (602) CALIFORNIA Basic Systems Corp, (213) Basic Systems Corp. (714) Basic Systems Corp. (408) ILLINOIS Electro-Tech Marketing Assoc. (312) Engineered Sales (312) INDIANA Audio Specialists (219) LOUISIANA Micro Computer of New Orleans (504) MARYLAND Systems International Inc. (301) MASSACHUSETTS S & S Electronics, Inc. (617) MINNESOTA 663-0375 Integrated Peripherals (612)831-0349 Vikeland Sales (612)645-4647 9671421 MISSOURI ESC Sales & Leasing (314)997-1515 673 4300 NEW YORK 268-8000 Washington Electric Co. (21 2) 226 2121 / (800) 221-5416 727-1800 Daily Business Products, Inc. (516) 543-6100 (800)645-5556/ (212)594-8065 588-4535 Synchro Sound Enterprises (516)484-1852 832-8425 PENNSYLVANIA QED Electronics (215) 674-9600 2345001 TENNESSEE Southland Video Distributors (800) 238-3274 885-5883 TEXAS Datanet, Inc. (214) 669-1758 977-0100 VIRGINIA Nine Associates, Inc. (703) 273-1803 458-41 oo Distributor inquiries welcome! "Registered Trademark of North Atlantic Industries, inc. AUSTRALIA Mitsui Computer Systems CANADA Computer Markets DENMARK T.M.S. Dataudstyr ENGLAND Northamber Limited FRANCE Gepsi GERMANY Technitron HONG KONG Computerworld Ltd. Hong Kong Equipment ITALY Eltron s.r.l. (030) 55026-41554-44414 NETHERLANDS Compudata Benelux B.V. 31-73-215700 SPAIN 2i Ingenierta Informatica 204-2099 02-9299921 416-445-1978 (45) 2-911122 (44) 372-67646 (33) 1-554-9742 49 (89) 692-4141 5-44033 5-453870 Circle 342 on inquiry card. ings are alike. They vary in size, strength, acuity, intelligence, educa- tion, and level of motivation. The general requirement for considering human factors in the design of your system, whether hardware or soft- ware, is to recognize the needs of the users. The type of user varies with the application. If you are designing an arcade game with a coin slot and two push buttons, you are aiming at a dif- ferent sector of the population than if you are developing a computer-based econometric model to predict the gross national product in 1985. Either of those programs can be written for specific, definable, homogeneous groups of users. More often than not, however, the hardware or software we design will be used by a varied group that ranges widely in sophistication. Knowing your system users and recognizing their needs are the first two steps in taking human factors into considera- tion during system design. In general, the rules for designing a system with the user in mind parallel those for good writing: define your system users, know their limitations, and find the simplest way to get your message across. That which separates good pro- grams from bad cannot always be described in terms of simple, obvious things such as bad keyboard designs or cumbersome error-handling proce- dures. I can name some general qualities to look for, however. First, programs that consider human fac- tors are generally easier to learn and use than those that do not. They usually have simpler displays, are less likely to "bomb," and are supported by good user documentation; they appear to be written for less special- ized users and not for computer ex- perts. These programs also refrain from trying to make the machine behave as if it were a human being. Poorly designed programs lack some or all of these features. To illustrate when human factors matter I'll limit my discussion to soft- ware design and, more specifically, to microcomputer software in which the operator controls the computer and interacts continuously with it. This scope includes such applications as games, business and scientific pro- grams, computer graphics, and com- puter music but excludes most con- trol, robotics, and other minimally interactive applications. A human-factors purist might say that serious consideration of human factors always matters, but this simply isn't true. You can decide in each case how important human fac- tors are by looking at four different aspects of your program: (1) number of people who will operate the pro- gram, (2) diversity of the operators' backgrounds, (3) complexity of the program, and (4) consequences of operator error. Obviously, the more people who will operate your program, the more time and energy you will invest in its development. If you are running a business, you want to assure that your A/R (accounts receivable) pro- gram works efficiently and effectively because it will cost you money and DATAFACE GRQ SERIES INTERFACE TURNS YOUR ELECTRONIC TYPEWRITER INTO A PRINTER/TYPEWRITER The Dataface GRQ-1 1 Interface expands your Olympia ES Series or Rem- mington 200 Series electronic typewriters into a let- ter press quality printer for your personal or business computer. And, you still have a fully featured elec- tronic typewriter — two machines in one. The GRQ Series Interface features: 1. Standard EIA RS-232-C Serial Interface and Parallel (Centronics compatible). 2. Standard asynchronous ASCII code, 7 bit data; 1 start bit; accommodates 1 or 2 stop bits automatical- ly; accommodates odd, even or absence of parity bit. 3. Fifty thru 9600 Baud data rate options. 4. Two K buffer; supports X-on, X-off protocol as well as RTS signals. 110 April 1982 © BYTE Publications Inc 5. Circuit board is installed inside typewriter back panel along side logic board. The connection between boards accomplished by 40 pin jumper cable using existing socket. No soldering required. Power is provided to the GRQ thru two pins of the 40 lead cable. Installation in 10 minutes. GRQ-10 — CALL FOR SPECIAL WHOLESALE PRICE. SUGGESTED RETAIL $349.50. DflTflFflCE inc. 2372 A WALSH AVE., SANTA CLARA, CA 95050 (408) 727-6704 Circle 136 on inquiry card. At Hayes, we don't believe in sec- ond best. Or planned obsolescence. We believe in taking the state of the art to the limit. Our new Smartmodem, for exam- histicated 300-baud jinaie/answer modem you can buy. And yet, it is perhaps the easiest-to-use modem ever. RS-232C Compatible. Smartmodem lets any RS-232C compatible computer or terminal communicate by phone with other computers and time-sharing sys- tems located anywhere in North America. You get full and half-duplex operation ind pulse dialing. Auto-Answer/ Dial /Repeat. Smartmodem can answerthe phone, dial a number, receive and transmit data, and then hang up the phone- automatically! if desired, Smartmodem wilt even repeat the last command. You can depend on trtmodem for completely unattended ttion. Completely Programmable. Smartmodem can be controlled usinq Microcomputer Component Systems any programming language. Over 30 dif- ferent commands can be written into your programs or entered directly from your keyboard. Smartmodem also includes sever- al switch-selectable features that let you tailor performance to your exact needs. You can "set it and forget if for the ulti- mate in convenience. Built-in Audio Monitor. Thanks to an internal speaker, you can actually listen to your connection being made. You'll know immediately if the line is busy or if you reached a wrong number - and you don t even need a phone! Status at a Glance. Seven LED's indicate Smartmodems current operatmc mode: auto-answer, carrier detect, off hook, receive data, send data, terminal ready and modem ready. You're never left in the dark! Direct-Connect Design. Smartmodem is FCC registered for i rect connection to any modular phone jack- there's no acoustic coupler to cause signal loss and distortion. Smartmodem, Smart Buy. Pro- fessional quality features. Versatile per- formance. A full two-year limited warranty. A suggested retail price of only $279. What more could you want? Per- haps the matching Hayes Stack Chrono- graph, an RS-232C compatible calendar clock system. Check out the Smartmodem wher- ever fine computer products are sold. And don't settle f w\ for anything less III LJ olfja€ * than Hayes I T J rfaVGS Smartmodem, The ultimate concept in modems is now a reality. * *. Hay§s Mj^^eompi pfee Corners East, Norcross, Georgia 30092 (404) 449- Mohly m >he u - A rp* Arnt. scan T t c-i <■*<. r ( « -» c Tviejun.^ 196? H^ves f le H on inquiry card. Products, Inc. perhaps your credit rating if it doesn't. If that same program must serve a wide group — ranging, say, from clerk to company president— then you must assure that the program serves all levels well. This takes special effort during program design. The more complex the program, the greater the chance of error, and the more you must strive to reduce the likelihood of error by carefully considering human factors. Last, and probably most impor- tant, are error consequences. The more serious these are, the more im- portant the human element becomes. If the reactor core will melt down, the navigator will get lost, or the names and addresses of all the people who owe you money will disappear, then the consequences of error are very serious indeed. If the worst that can happen is that the bouncing ball in your game program may disappear from the screen, then the conse- quences are not quite so serious (unless you depend upon the program for your livelihood). In sum, if you are writing programs purely for your own use and are not tracking important data, then you have probably spent too much time on this article already. On the other hand, if you are writing programs for a wide and varied group of users to track things that matter to them, then human-factors considerations are im- portant. Design Principles If you decide to apply human fac- tors to your program design, where do you begin? Probably the best way is to familiarize yourself with some general human-factors design princi- ples. Six such principles are presented below. These principles grow out of behavioral research conducted over the last several decades, although their application to program design is recent. Later in this article I'll give Now there is an affordable, high performance, 5 1 /4-inch disk drive that is fully compatible with your Apple — and compatible with your pocketbQok. The A.M. Electronics drive comes complete with an Apple- beige case and connecting cables It's fully tested with Apple's disk operating system and software. Just plug it in- it's ready to run. You also receive a 90-day limited warranty and a 10-day money back guarantee. Order Today. The Apple-compatible disk drive is now available direct from A.M. Electronics for only $395 (40 track) or $495 (80 track). Upgrade your Apple with our disk drive today and increase the fruit of your labor. Am A.M. ELECTRONICS, INC. '-■..:■:■■•. 3446 Washtenaw Avenue «Ann Arbor Ml 48104 313/973-2312 Attention Dealers & Distributors: For information on attractive pricing and sales opportunities, call us today. Key territories are stili available. rn specific examples of how these prin- ciples may be applied. Provide Feedback: People need to know that an action they have taken has had an effect. When you turn the wheel of your automobile, you re- ceive feedback in the form of resistance from the wheel, centrifugal force on your body, and movement of your visual field. In turn, you adjust the rate at which you turn the wheel to conform to the feedback you are receiving. Without this feedback, you would find it much more difficult to control your automobile. The user of your program also needs feedback. If he makes a key- board entry and nothing appears on the screen, then he has no way of knowing that his action has had an effect. In consequence, he may repeat his action or try another, possibly causing something unintended to happen. Feedback should be immediate and obvious. Show it on the screen in a place where it is expected. Be Consistent: Mention "consisten- cy" in a group and someone will probably quote Emerson to the effect that it is the "hobgoblin of little minds/' Emerson may have been able to get along without it in certain trivial matters, but computer pro- grammers cannot. The tools and pro- gramming languages with which they work are based on rigid adherence to rules of syntax, the order of program- ming operations, and the laws of mathematics. Rigid adherence to these "laws of the machine," which are internally consistent, reduces un- certainties and makes it possible to program the machine exactly. Human beings can tolerate more ambiguity than machines, but ambiguity re- duces people's effectiveness. If we paid half as much attention to con- sistency in our programs' interactions with human beings as we do in the in- teractions between programs and machines, most of our programs would be improved. What, exactly, do we mean by "consistency"? One way of defining it is as a set of rules that you, the pro- grammer, establish for yourself and follow compulsively. These rules per- 112 April 1982 © BYTE Publications Inc Circle 2 on inquiry card. 64K at 8MHz Static RAM PLUS HIGH STANDARDS The bus standards are theirs (the IEEE's 696/S-fOO). The quality standards are ours. The combination of price, performance, and rsatility sets NEW standards unmatched by any other EPROM- ipatible memory on the market. 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Available partially populated to 48K or 32K. *CROMIX is a trademark of Cromemco. *MP/M is a trademark of Digital Research. NO RISK TRIAL All Indigo Tech products are sold on a no- risk basis. If not completely satisfied return board within 1 5 days and the full purchase price will be promptly refunded. MI 2/64 64K $725.00 Ml 2/48 48K S 645.00 Ml 2/32 32K $595.00 Shipping and handling $5.00 per board. Visa or Mastercard accepted. California residents add 6% sales tax. indigo tech 670 NUTTMAN AVENUE, SUITE 1 10 SANTA CLARA, CA 95050 • (408) 727-4710 Circle 204 on inquiry card. mit the operator to learn one part of your program's operation and then to apply the new knowledge to other parts of the program. For example, you might make a rule that all of your error messages will appear on the bot- tom line of the display screen. When the operator sees one error message displayed on the bottom line, he ex- pects all others to be displayed there, too. If they are, then the rule is ad- hered to, and the operator will not have to learn a new rule for each new display. If not, then the operator's learning task is that much more dif- ficult. Minimize Human Memory Demands: Psychologists have deter- mined that human beings possess two types of memory — short-term and long-term. A vast amount of research has been conducted on the subject, most of which will interest only the specialist. About human memory, the computer programmer needs to recognize two things. The first of these is obvious, the second less so. First, computers have better memo- ries than people. (We said it was obvious.) Data stored on magnetic media are never forgotten. Second, computers always remem- ber things exactly as they were stored. People usually do, but some- times they get things mixed up. What follows from these two points is that, when designing pro- grams, you should rely on computer memory as much as possible. Sup- pose, for example, that your program has many subprograms. How should the operator select a subprogram — from a displayed menu or by entering a memorized mnemonic? Although selection with memorized mnemonics (used in 'program-like languages") has advantages in some situations, the displayed menu depends much less on operator memory and is generally preferable. (Some players of Star Trek games may recall the frustration with which they S-100 BUS (CP/M) Heath H89, H90 (CP/M, HDOS) Zenith Z89, Z90 (CP/M, HDOS) TRS 80 Model (CP/M, TRS DOS) Xerox 820 (CP/M) IBM Personal Computer (CP/M 86, IBMDOS) AMTs EZ8X5 is a complete, ready to plug in Winchester Hard Disk Sub- system. Featuring easy implementation, enhanced system interface cards, an extensive disk test package. The EZ-8X5 delivers a full 5, 10, or 20 megabytes. Dealer and Distributor inquiries are being accepted HliiE Route 30 West Greengate Professional Building Greensburg, PA. 15601 412/837-7255 or call Toll Free 1-800/245-6908 • . • If s What's Inside That Counts. attempted to master the game in the absence of displayed menu options.) Keep the Program Simple: Simplicity in programming, as in writing, does not come easily or pain- lessly. You must work to achieve even the appearance of simplicity. Simplicity usually results from paring down or editing. In programming, as in writing, simplicity is an ideal that one strives to achieve by conscious design, by trial and modification, by cutting away the unnecessary, and by reorganizing and rearranging. Match the Program to the Operator's Skill Level: You must determine the operator's skill level before you write your program. Determine also if operators of differ- ing skill levels will use the same pro- gram. Human-factors specialists do these two things systematically by conducting a task analysis. There are several ways to do this, but usually it involves defining what mission a system must perform, what functions are involved in this mission, and what tasks are required to accomplish the functions. Conducting task analyses is time-consuming, tech- nical, expensive, and probably beyond your needs or interests. Still, you do need to think about operator tasks as you write your program and ask questions like the following: • What will operators be expected to do? • What decisions must they make? • What must they know to make the decisions? • What skill levels will be required? Consider these questions before you write your program. Then design your program so that it matches the skill level of your system users. Sustain Operator Orientation: If you have ever been lost then you know what not being oriented is. Anyone who has ever used a com- puter has had the experience of get- ting into some new program and not being able to find the way out. This often happens when you try the pro- gram without first reading the manual (as all of us are prone to do). You have an obligation as a pro- 114 April 1982 © BYTE Publications Inc Circle 38 on inquiry card. APPLE • ALTOS • ATARI • MAXELL • DYSAN • EPSON • CCS • SHARP • CASIO • HP • VERBATIM • MEMOREX • SOROC • CORVUS • ADDS /MICRO TI-99/ SEC S PRINTER BUSINESS WORLD INC. Information Line (213) 996-2252 TOLL FREE MAIL ORDER LINES (800) 423-5886 outside Cam. r < SHARP BUSINESS COMPUTER s 64K SYSTEM %•*■* * 5.25" diskette ^ * 284K byte per disk drive * 2 disk drives per unit * Expandable up to 4 units * Including SHARP'S FDOS (Floppy * Disk Operating System) MSL OUR PRICE ^^^SS 599500 $3995.00>^ isa: HEWLETT ARC HP 125 Microcomputer HP 85 Microcomputer HP 83 Microcomputer 16K ExpMemory Module Graphics Plotter 7225 Personality Mod. 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Phs. Video Monitor <&* EPSON MX 80 FT MX 80 IMPACT MX 70 IMPACT MX 100 ANADEX 9501 NEC 5510 5515 3510 3515 OKIDATA MICROLINE 80 MICROLINE82 MICROLINE 83 PAPER TIGER 445G with Graphics 460G with Graphics 560G New full size DIABLO (LETTER 630 R 102 bi-directional tractors 1640K109 keyboard tractors 630 RO Receive Only 1650K 136 keyboard fc tractors 795.00 1,394.00 1,695.00 1 QUALITY) 2965.00 : 4.000.00 2,710.00 2,899.00 2,250.00 4.000.00 3,100.00^ 12" Grn. Phs KQ (15 Hz) 12" Grn. Phs £0(18 Hz) 12" Grn Phs (20 Hz) 12" Colour Composite Hi Res. Grn. Phs 12" NEC Grn. Phs. 12" Zenith 12" LE MONITOR * 9-B&W . * 9" Green Phs V *V - * 12-B&W S V>* * 12" Green Phs. 4 *• 12" Green Phs. * Anti Reflective Screen ** T.V. Grade Screen SANYO MONITORS 13" Color (new) high quality 12" Green Phs. 12" B & W 15" B & W 9" B & WThe Bestseller! 9" Green Phs. 219.00 1249.00 279.00 439.00 275.00 225.00 159.00 179.00 189.00 209.00 229.00 199.00 $550.00 360.00 340.00 370.00 235.00 275.00 165.00 185.00 209.00 319.00 165.00 179.00 119.00 159.00 165.00 185.00 199.00 159.00 399.00 269.00 239.00 255.00 159.00 199.00J AVINGS ERVICE ELECTION ATISFACTION Egrfo] XEROX 820 WORD PROCESSING SYSTEM (INCLUDES SOFTWARE) 5*1 OUR PRICE c* „ ojcnn MSL $2649.00 >**e 846.00 3495.00 TELEVIDEO 910 91 2C 920C ^950C 104/1 5" SOFT SECTOR 104/10 =" DBL. DEN-SOFT SEC 3740/1 8" SOFT SECTOR 3740/1D 8" DBL DEN.SOFT SECTOR MAXELL MD-I 5" SOFT SEC- TOR/DBL. DEN. MD-2 " SOFT SECTOR/DBL. SIDE./DBL. DEN. FD-I 8" SOFT SEC./DBL. DEN. FD-1 8" SOFT SEC./DBL ^SIDE/DBL. DEN Our ist Price J 699.00 J 599.00 950.00 699.00 995.00 795.00 1.195.00 949.00 DISKETTES sold in boxes of 10 (Min. Purchase) $100 Ljst DYSAN PRICE PER DISKETTE Our Price 4.60 4.75 6.40 7.25 5.00 7.00 ^1 Our List Price 750.00 S3.050.00 .350.00 4,449.00 6.45000 5,325.00 EXPANSION BOARD QSTAR 16K RAM BOARD LIST OUR PRICE 199.00 129.00 SOFTWARE FOR APPLE II Language System with Apple Pascal BPI General Ledger System Visidex Visicalc Desktop Plan II Microlab Database System Stoneware DB Master Muse Supertext II Softape Magic Window Q commodore COLOR COMPUTER \f|£^20 il 1 5 VicTV Modual .T77TT.S 19.00 Vic Cassette $69 00 Vic Disk Drive Hall Vic 6 Pack program $44.00 MSL 299.00 our price Save $255.00 4400 FOR COMMODORE Ozz The Information Wizard Wordcraft 80 irma-jnfo Retrieval & Mgmt Aid Dow Jones Portfolio Mgmt. Pascal Development Pkg. Ebs-Receivables, Inventory Bpi General Ledger Word Pro 340 Column Word Pro 4-80 Column ^Word Pro 4 Plus SOFTWARE Lis! 395.00 395.00 495.00 149.00 295 00 750.00 395.00 250.00 375.00 450.00 Our Price 1289.00 289.00 389.00 119.00 219.00 569.00 389.00 175.00 259.00 319.00^ MODEMS, „ List NOVATION CAT MODEM ^^ 189.95 NOVATION 0-CAT 199.00 NOVATION APPLE-CAT 389.00 HAYES MICROMODEM 379.00 HAYES SMARTMODEM 279.00 Our Price 140.00 150.00 329.00 295.00 239.00 •J | CALCULATORS/! CASK) HR 10 Paper Feed HR 12 Paper Feed FR-100 Paper Feed FR-1210 Paper Feed PQ-20 LC-785 LC-3165 FX 68 Scientific FX 81 Scientific FX 3600P Scientific FX-602P "Computer Talk' 88 Memories Pro gramming Upper & Lower Case Dot Matrix 512 Step 129.95 FX-702P Solves Problems with Alpha- Numeric Clarity, uses Basic Language 199.95 49.95 54.95 79.95 129.95 29.95 12.95 12.95 29.95 19.95 39.95 Our Price 39.00 42.00 59.00 99.00 23.00 10.00 10.00 23.00 17.00 29.95 TELE. ANSW. DEVICES PHONE MATE 900 Economy 905 Remote Dual Tape Sys. 910 60 Calls Per Side 920-C Vox 925 Remote Call Monitor 930 Remote Twin Cass. 950 Remote 960 Remote Built In Tele Microcomputer Controlled A \ 1 2 Ji/I ■ r"»Q|—l BUSINESS WORLD ■ ■^^■1^^ WAREHOUSE 1 M OUTSIDE CA CALL TOLL FREE Name (Please print) „ Address ^___ City Stati 3720 Oxnard, #108 Tarzana. CA Pnnsfi I (800) 423-5886 IN CA (213) 996-2252 Qty Make Model Description Price Total Telex: 182852 Answer: MICKO TZNA 'California residents add 6% sales tax. "Add 3% Shipping & Handling - Add 3% surcharge for credit cards. Orders cannot be shipped unless accompanied by payment, including shipping, handl- ing and tax where applicable. TOTAL ORDERS TAX IF APPLICABLE* SHIPPINGS HANDLING" „ TOTAL ENCLOSED $ » I D Certified Check or MO. D Bank Wire Transfer CREDIT CARD* Exd. Date D Allow 2 weeks clearance for personal check VISA .Signature MAXELL • DYSAN • EPSON • CCS • SHARP • CASIO • HP • VERBATIM • MEMOREX • SOROC • CORVUS • PERSONAL SOFTWARE • CCS Circle 257 on inquiry card. BYTE April 1982 115 DATA COLLECTION FORM Daily Man-hour Availability / / NAMES MAN-HOURS Available Direct Overtime DATA ENTRY SCREEN Daily Man-hour Availability } Date (Month/Day/Year) MAN-HOURS NAMES Avail. (0-12.0) Direct ( 0-12.0) Over, (0-4.0) I i } ( ) II } { i i } I ) I I } { I i I Figure 1: A data-collection form and the data-entry screen that goes with it. The data- entry screen resembles the form. Prompts shown in parentheses on the screen make clear the expected data formats and give range limits. The brackets serve as field delimiters, showing the maximum length allowed for each entry. grammer to minimize the possibility of disorientation. Provide your operator with signposts that tell him where he is and how to get back to where he came from. Menu-driven programs often do this by providing a main menu which serves as a home base. The program begins with this menu from which the operator can select various subprograms, perform them, and then return. Some game programs are inten- tional mazes, consciously designed to disorient the operator. If that's your intention, all well and good. But if it's not, remember that an unwanted maze is about as much fun as an inac- curate road map on a dark and rainy night. The six principles described above reduce to one idea: know the needs of your system users. Recognize that they need feedback to avoid confu- sion, consistency to ease the learning process, minimal strain on memory capacity, simplicity rather than com- plexity, demands gauged to their skill levels, and constant, clear orienta- tion. The remainder of this article will focus on three areas of computer pro- gramming: data entry, display-screen design, and sequence control. Data entry concerns how you get data into a database; display-screen design concerns layout of video-terminal- display screens; and sequence control concerns how you interact with your program to get it to do something. I'll show how the six human-factors principles apply in each of these areas. In most cases, recommenda- tions made are based on research that has shown that the suggested feature permits more effective man-machine interaction. In a few cases, recom- mendations are based on prevailing practice. None of these guidelines should be applied blindly, and all of us will find it necessary to ignore them from time to time. But most of these are simple things to do, and if you follow them, you will write a better program. Data Entry The following guidelines apply mainly to programs in which data are entered through the keyboard to build a database which the program accesses later. Typically, the data entry process consists of the follow- ing sequence of steps: • presentation of a prompt • data entry by the operator • display of entered data on the screen • error test • presentation of an error message if entered data fail error test • editing of data • acceptance of data into database Prompting: If data are to be entered into the computer from a standardized data-entry form, then the data-entry screen should resemble that form as closely as possible. The cursor should move from field to field as the operator fills in the form. It is easier to write a program consisting of a series of INPUT statements that cause the screen to scroll. However, the operator can more readily orient himself to a screen that looks like a data-entry form. Figure- 1 shows a data-collection form and a data-entry screen designed to elicit the necessary data. The screen presents prompts, states acceptable ranges, and delimits fields. The program should provide a prompt for every data input. The prompt should be brief and specific, and show the range limits and entry 116 April 1982 © BYTE Publications Inc Circle 345 on inquiry card. • Quality Computer Services presents, . $3195. ForT 6,12,20,40 and 00 Megabyte systems Completely assembled and tested subsystem including: • Switching power supply • Winchester drive • Host adapter card • Sealed case • Expansion The encloser, controller and power supply have been designed to allow for future backup hardware or increased storage • Software • Auto attach CP/M* • Hard disk utilities • Real time clock t • Formatting program Assigns alternate sectors for any weak sectors detected during formatting assuring the lowest possible error rate • Warranty: The system has a full one year warranty on all parts and workmanship • Also available: attach for TRSDOS, OASIS*, Apple DOS shown) ♦-- ^Wffe- ^, m Sis' ,Jr Hi See local dealer or call: Quality Computer Services 170 Main Street Metuchen, New Jersey 201-548-2135 • Quantity discounts av and OEM inquries invited. H number: 800 631 5944 2/31/1979 | Date (Month/Day/Year) DATA ENTRY ERROR: Date contains invalid DAY -- re-enter date Figure 2: A sample error message. The message is specific and helps the operator correct the error identified. format of data to be entered. Range limits or entry format can be shown parenthetically after the prompt. For example, a date entered in the form of month-day-year could be prompted as follows: "Enter Date (Month/ Day /Year)/' If there is a length limit, then this length should be shown on the screen using an underline, pair of brackets, or other visual cue. If cer- tain data entries have default values (i.e., values that the computer will assign unless the operator enters others), then display the default values — do not rely on operator memory. If there are similar or iden- tical data-entry requirements in dif- ferent parts of the program, prompt consistently. One way to do this is to put data-entry statements into sub- routines that can be called from various parts of the program. Entering Data: You do not always control the length of the data to be entered, but when you do, keep length to a minimum. This saves key- strokes and time and reduces errors. Provide feedback by displaying entered data on the screen. If data be- ing entered consist of logically related groups, then permit the user to enter several fields together, rather than re- quiring him to enter each item sepa- rately . Error Check: Check all entered data for errors. The types of checks you must make depend upon the data and what will be done with them. An- ticipate possible errors, check for them, and protect against them. For example, if the entry is supposed to be a number, anticipate what will happen when (not if) the operator enters a letter. Many programmers protect against this by taking all in- puts as character strings and then converting them to equivalent numer- ic values. Analyze the situation and be ready for errors. Are there range or length limits to what is acceptable? Is it possible for the operator to enter something that will cause an illegal program action to take place — for ex- ample, dividing by zero or attempting to take a substring of illegal length? When an entry error is detected, alert the operator, identify the error, and tell him how to recover. In other words: alert, identify, direct. Alerting signals must differ from the custom- ary background. An audio tone — a beep — is alerting but meaningless if the program is already emitting a continuous stream of beeps. Similar- ly, a flashing message can effectively alert, provided that the screen is not filled with other flashing messages. Many programmers reserve the use of both sound and flashing messages for those conditions that truly require an alert. The error message itself should be placed consistently from screen to screen. Ideally, it should appear near the erroneous entry. The content of the message must tell what is wrong — for example, that the entered value is too long. If error identification will permit the operator to figure out what to do next, then that is all the message needs to contain. However, if many possible actions may be taken, then the message must also tell the operator which to take. If prompts to the user are adequate, then it should be possible in most cases for the operator to figure out what corrective action to take based solely on definition of the error. Figure 2 shows a helpful error message. Editing: Editing is an important part of the data-entry process, and no data-entry program is complete with- out editing capability. Being human, operators will make data-entry errors that they may not recognize until later. You should therefore permit them to edit entries before the pro- gram accepts data into a database. Many programs permit data to be edited at three stages: during initial data entry (while being typed in), after a block of related entries has been made, and after the data have become part of the database. The first editing capability is rou- tine and in fact most people probably do not think of this as editing. If you make a typing error, you can usually back up the cursor before data are stored. The last capability, editing the actual database, varies in impor- tance, but in many programs with large databases it is considered as necessary as utility programs for copying files, purging files, or the main menu itself. Less routine, often ignored, yet very important is the block editing capability mentioned above. Often the program user will not recognize an error until after he has made several data entries. If he cannot go back and correct the error at that point, it may be uncorrectable, or he may have to use a separate database editing program to make the correc- tion. The way block editing typically works is that after the operator has made a set of related entries, the screen presents a prompt asking if he wants to edit any earlier entries. If he 118 April 1982 © BYTE Publications Inc r"My computer helped me write The Final Encyclopedia I wouldn't trust anything less than Scotch" Brand Diskettes to make a long story short" Gordon R. Dickson, Science Fiction Author, Minneapolis, Minnesota Gordon Dickson: a small business- man whose product is his own imagination. He's written more than 40 novels and 150 short stories; his newest work is The Final Encyclopedia. He uses his personal computer and word processing software to maximize his production. All his words-his product- are stored on diskettes. He calls up sentences and paragraphs on demand, and gets more rewrite out of the time available. So he depends on Scotch diskettes to save himself production time. Dependable Scotch media can work just as hard for you. Each Scotch diskette is tested before it leaves ourfactory, and certified error-free. So you can expect it to perform exactly right. Scotch 8" and 5 1 /4" diskettes are compatible with computer/diskette systems like TRS-80, Apple, PET, Wang and many others. Get them from your local 3M distributor. For the one nearest you, call toll-free: 800/328-1300. (In Minnesota, call collect: 612/736-9625.) Ask forthe Data Recording Products Division. In Canada, contact 3M Canada, Inc., Ontario. If it's worth remembering, it's worth Scotch Data Recording Products. cUske 3M Hears You. Circle 414 on inquiry card. . ORANGE MICRO JUST TURNED IN PRINTER HISTORY. OUR PRICES, SELECTION & SAME-DAY SHIPPING MAKE US COMPETITIVE. NEC 8023 Outstanding Graphics, Print Quality & Performance 144 x 160 dots/inch ■• Proportional Spacing • Lower case descenders • Nx9 dot matrix • 8 character sizes • 5 unique alphabets • Greek character set • Graphic symbols • 100 CPS print speed • Bi-directional logic- seeking • Adjustable tractors * Single-sheet friction feed • Vertical & horizontal tabbing NEC 8023 £f*lll Dot Matrix List $795 ptsdll IDS Paper Tiger 560/Prism 80/132 Affordable Color, Speed Dot Resolution Graphics • 9-wire staggered prmthead • Lowercase decenders • Over 150 CPS • Bi-directional, logic-seeking • 8 character sizes • 80-132 columns • Hi-res dot graphics • Proportional spacing • Text justifications Prism 80 List $899 $700 IDS Paper Tiger 560G . . . List $1395 $1100 Prism 132 (Color) List $1995 $1895 NEC Spinwriter 7700 & 3500 Daisy Wheel Quality Leader High speed, letter quality • 55/33 CPS • Typewriter quality • Bi-directional plotting & proportional spacing • Quiet • OCR quality print • Hi-res plotting/graphing • Quick change ribbon • Optional cut-sheet feeder, horizontal or bidirectional tractors • Prints up to 8 copies. NEC Spinwriter RO Serial Parallel 77xx List $3055 $2575 35xx List $2290 $1975 The Epson Series. High-Quality Printers at a Low Price. !f Epson MX70 Super low priced dot resolution graphics • 5x7 dot matrix • User replacable prmthead • Top of form • 80 CPS optional friction feed • 10" paper width COQft Epson MX70 List $450 ^u" U Epson MX80/MX80FT 9x9 dot matrix • Lower case decenders • 80 CPS • Bi-directional • Logic seeking • 40. 66. 132, columns per line • 64 special graphic characters: TRS-80 Compatible • Forms handling • Multipage printing • Adjustable tractors Of*«*II Epson MX80 List $645 0L>3il Epson MX80FT List $745 SCall Epson MX100 Same basic features as the MX80 • Plus friction feed for single sheets • Plus 15" wide carriage • Dot Resolution Graphics Af*_|| MX100 List $995 pLdll Full Line of Epson Accessories Anadex 9501 High Speed, Commerical Duty Plus Graphics Dot graphics • Wide carriage • 11x9 dot matrix • Lower case descender • Dot resolution graphics • Bi-direcitonal. logic seeking • Up to 200 CPS • RS 232 Serial & Parallel • Forms control • X-On/X-Off • Up to 6 part copy OlOCfl Anadex 9501 List $1650 y 10311 INTERFACE EQUIPMENT Complete stock of options, cables and accessories. GRAPPLER APPLE INTERFACE $175 CCS APPLE SERIAL Interface & Cable $150 ORANGE INTERFACE for Apple II Parallel Interface Board and Cable $110 NOVATION D-CAT direct connect modem $180 COMPLETE STOCK OF EPSON ACCESSORIES $Call CUSTOM PRINTER CABLES FOR Apple, Atari, IBM, TRS-80 (all models) $Call HAYES MICROMODEM $300 PRINTER STANDS: Large $99 Small $25 PRINTER RIBBONS— Most Types $Call E'RE NOW Red Baron COMPUTER PRODUCTS OUR PEOPLE MAKE US EXPERTS. Maiibu 200 Dot Matrix & Letter Quality in One Printer 200 CPS standard • Letter quality font • 12 optional fonts • Bi-directional logic seeking • 19x18 dot matrix • Expanded characters (2x, 4x) Optional • Dot resolution graphics of 144 x 120 • Underlining ^#%*%*»** Maiibu 200 List $2995 $2600 Okidata 82A Hi-Res & TRS-80 Block Graphics Mf' 120 CPS • Bi-directional printing • Logic seeking • Double width & condensed printing • Friction & tractor feed standard • Font selection, character pitch & line spacing are program controllable CP^II Okidata 82A List $799 uOdlt Centronics 739 Crisp Dot-Matrix Characters Graphics & word processing print quality • N x 9 dot matrix • suitable for word processing • Underlining • Proportional spacing • Right margin justificaiton • Serif typeface • 80/100 CPS • 9V 2 " pin feed/friction • Optional 2 Color Kit Centronics 739-1 ...... List $695 Centronics 739-3 List $795 SCall $725 Our People, Our Product: Both Are Specialized. Because our salespeople are printer specialists, they know the capabilities of each printer— and how to match one to your exact need. Red Baron's volume stocking assures a low, low price on a wide array of major brands. We're sure you'll like the product and services you get from Red Baron, and we know you'll love our Customer Benefit Package; an exclusive at Red Baron. Customer Benefit Package 1. Free Expert Consultation. Before you buy, after you buy. 2. Toll-Free Ordering. There's never a toll charge when you place your order at Red Baron. 3. Free Catalog. Get your informative catalog with printer comparison chart and character samples today! 4. Warranty. The manufacturer's warranty applies where applicable. 5. Same-Day Shipping. Your order is sent the same day when you call before 1 1 :00 a.m. 6. Free/MasterCard & Visa. Call us toll-free and charge your printer to your credit card. 7. We Stock What We Sell. No bait and switch, no hassle. We make every effort to keep a large stock of our advertised products. Televideo CRT's Price, Performance & Reliability 910C List $699 920C List $995 925C List $995 950 List $1195 $600 $770 $750 $970 Here's how to order. Phone orders are welcome; same-day shipment on orders placed before 1 1 :00 a.m. Free use of Master- Card and Visa. CODs accepted. Personal checks require 2 weeks clearance. Manufacturer's warranty included on all equipment. Prices subject to revision. Orange Micro Retail Stores Sherman Oaks: 13604 Ventura Blvd. (213) 501-3486 Anaheim: 3150 La Palma, # I (714) 630-3622 Santa Clara: 3216 Scott Blvd. (408) 980-1213 Circle 309 on inquiry card. CALL FOR FREE CATALOG TOLL FREE Red Baron COMPUTER PRODUCTS 1100 N. TUSTIN ANAHEIM. CA 92806 CA, AK,HI 1-800-854-8275 (714)630-3322 A * * WARNING * * You have selected the 'PURGE FILES' program. If you use it, your data files will be purged. Do you want to continue with the PURGE program ? I Y/N )_ Figure 3: A message that protects the operator against a serious error. The operator must confirm the decision to purge the data files before the program will proceed. indicates that he dees, the program asks him to define the entry he wants to correct, usually by line number. Then the cursor moves to the appro- priate data-input field to permit re- entry of data, and the edit prompt re- appears to permit corrections. When the operator indicates that he has no more changes to make, the program moves on to the next step. Certain data entries have far- reaching effects. A 'profound, irre- versible data entry" is one that will significantly affect the database or a phase of program operation. How profound the data entry is depends, of course, on the situation. Conse- quences of data-entry errors in these cases vary from inconvenience (you are delayed because you must print a report) to disaster (you just purged six months' worth of data). Clearly, it is important to protect the operator from such traps by pro- viding "fail-safe" devices. The general idea is to make the operator action more complex than for usual data en- try. One way is to make data entry require two stages. For example, when the operator selects the "FIRE ICBM" program from the menu, fir- ing does not occur immediately but causes a message to appear on the screen that tells what will happen next. This is accompanied by a prompt that permits the operator either to continue or to back out. Protect your operator against him- self. The programmer who writes a program that will purge all files at the stroke of a single key deserves no mercy and will receive none from program users. Figure 3 shows a message that provides sufficient warning to the operator before begin- ning to purge data. Display Screen Design Screen layout design is partly art and partly science but all program- mers can profit by observing the guidelines in this section. Designing a good screen requires planning. Many experienced pro- grammers find that a screen design aid, consisting of a paper matrix that identifies all possible character loca- tions on the screen, is useful. This permits design of the screen with paper and pencil. The design can be perfected before it is committed to code. (It is much faster to make pencil erasures than to change a series of tab settings.) As a general rule, access screens by paging, not by scrolling. Keep in mind that people find it easier to read stationary pages than moving pages. The only people who like to read scrolling information are those at the end of hot news wires. Unless your program has that sort of application, clear the screen before you put up a new display. Most displays need a title to tell the operator what he is looking at. The title should be centered at the top of the screen. Display screen designers center dis- played information primarily for aesthetic considerations, although centering assumes more practical im- portance with large screen displays. With large screens, if information is not centered, the operator will spend his time turned to the left side of the screen instead of along a more natural line of sight— straight ahead. Your screens will probably contain a variety of different types of infor- mation: title block, numerical infor- mation, prompt line, error-message line, operating-mode indicator, etc. Analyze your needs and determine how many different categories apply. Then allocate a screen area for each information category. Assure that information on screens does not stray from its assigned area. This is an application of the con- sistency principle discussed earlier. The more complex your screen dis- plays, the more important it is to allocate areas. If you have complex screens and do not design them con- sistently, you will confuse the operator. If possible, separate each area of the screen from the next by at least three rows or columns of blank spaces. Different blocks can also be separated by lines, which will make the separation more distinct. More ef- fective still is to color-code different screen areas. "Keep it simple" has become a cliche but is valuable and important advice. Unfortunately, keeping it simple is, to use another cliche, easier said than done. What, after all, is "simple"? And when is something "not simple enough?" Finding the answers to these ques- tions requires you to take a close look at the information needs of your pro- gram users at each point in your pro- gram. Present no more information than necessary. Some programmers use the "one logically connected thought or step per screen" rule. Where much infor- mation must be conveyed, these pro- grammers break it up into logical thoughts or steps and present each one on a separate screen. This is like the rule of presenting one idea in each paragraph of prose. Programmers in the "densely packed display" school of thought hold the view that if they can get 122 April 1982 © BYTE Publications Inc IBM COMPATIBLE BOARDS BY IV MEMORY WITH PARITY Limited time only! $598 £ 5^9^^ HARD DISC SUBSYSTEM FOR IBM and S - lOQ $2495 HAB2 IBM BUS HARD DISK INTERFACE FOR WD-1000 4SP 4 SERIAL PORTS FOR IBM PB PROTOTYPING BOARD FOR IBM EB EXTENDER BOARD FOR IBM S -lOO BOARDS ZOBEX CPU Z-80A CPU WITH 4 SERIAL AND 3 PARALLEL PORTS ZDBEX DDFDC DOUBLE DENSITY DISK CONTROLLER ZMS-100 64 K RAM HDCI S-100 HARD DISK INTERFACE FOR WD-1000 ZOBEX 7343 J. RONSON RD* SAN DIEGO, CA. 92111 C714] 5 71-6371 ZOBEX is trademark of ZOBEX CORPORATION IBM is trademark of International Business Machines Corporation Circle 446 on inquiry card. BYTE April 1982 123 NOT THIS THIS Personnel Directory NAME Knuth Sams Lien Bowles King Grogono Liffick } Personnel Directory NAME Bowles Grogono King Knuth Lien Liffick Sams Figure 4: The same list presented in random order and in alphabetical order. Recognizable orderings—e.g. , alphabetical, numerical and chronological—make data easier for the operator to comprehend. everything onto one screen they are saving something. What, exactly, they are saving is unclear, although they must gain a certain satisfaction by rising to the challenge of making everything fit. This satisfaction resembles the exultation of the first guy who engraved the Declaration of Independence on the head of a pin. Judge for yourself how useful that was. In designing screen displays, it is important to follow prevailing con- ventions. Because of experience with written language, people have certain built-in expectations for the way in- formation will be presented to them. If you don't follow convention in dis- playing information, you make things more difficult for the operator. Think of your display screen as the page of a book. In a book, informa- tion is normally presented in lines that are read from left to right and from top to bottom. Numeric infor- mation is usually presented in tabular format, i.e., beneath column head- ings and from top to bottom. Certain obvious things you should avoid are printing numeric information from left to right or presenting very wide columns of text. If in doubt, recall how you have seen such information portrayed in books. You should display information in a recognizable order. Some screens present directories or lists through which the operator must search. A menu is one such list, although it is usually short, with the most frequent- ly called options listed at the top and the least frequently at the bottom (more on this later). Long directories or lists should be presented in an order that the operator will recog- nize, for example, alphabetic, numer- ic, or chronological order. This simplifies the search and saves time. Figure 4 shows the same information presented in random order and again in alphabetical order. Judge for your- self which ordering makes it easier to find the name "Grogono." Long strings should be broken up. A "long" string is one that has more than about five independent charac- ters. By "independent" we mean char- acters that do not unite to form a re- cognizable whole such as a person's name. A telephone number without the separating hyphen would be such a string. People have difficulty recog- nizing and separating the individual characters of long strings. If you have 124 April 1982 © BYTE Publications Inc Circle 330 on inquiry card. I learned that I could get specific advantages when purchasing from A.E.I. A.E.I, has valuable knowledge gained from selling millions of dollars of computer equipment, and will take the time to discuss which equipment is right for me. Based on its vast experience, A.E.I, sells only reliable equipment. A.E.I, can test and configure equipment to match my system. A.E.I, will initalize my software to match my system, saving me valuable time. A.E.I, stocks repair parts and can answer my "I found out why V.I.P.'s call A.E.I." technical questions, and expedite repairs to my equipment when necessary. A.E.I, is price competitive even when compared to No- Service sales companies. I learned that 40% of all A.E.I, sales are to public and semi-public institutions* such as the Universities of Nebraska, Virginia, Kentucky, California, M.I.T., the U.S. Air Force, Princeton; as well as scores of major corporations. Calling A.E.I, is the smart thing to do. *A.E.I. does not wish to imply that any of these fine organizations endorse A.E.I., merely that A.E.I, is proud to have them as customers. A PARTIAL LIST OF PRODUCTS AVAILABLE AT A.E.I. TELEVIDEO COMPUTER List Sell TS800 User Station 1795 1450 TS-801 Computer 3295 2650 TS-802 Comput/Terminal 3495 CALL TS-802H Comput/Termin. 6995 CALL TS 806 Multi User Pfoc. 7195 5749 NEC PRINTERS List 3510-1 30CPS Serial 2450 7710-1 55CPS Serial CALL 7720-1 KSR Serial CALL Forms Tractors CALL NORTHSTAR HORIZON PRODUCTS List Sell HRZ2Q-64K 3599 CALL HRZ10-64K-HD5 6695 4999 HRZ 1Q-64K HD18 9270 6749 NorthStar is discontinuing many ol their horizon products. 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MORROW DECISION COMPUTER List Sell Decision 1 BASIC 1725 1350 65 K Static Ram 1000 780 Switchboard I/O 259 210 Select drives from Morrow disc systems for desired configuration MORROW DISC SYSTEMS List Discus 20 1 Drive 1095 Discus 2D 2 Drive 1875 Discus 2 + 21 Drive 1395 Oiscus 2 + 22 Drive 2495 M 26 Hard Disc 4495 CP/M & Microsoft Basic Included LINE PRINTERS Okidata 82A Okidata 83A Anadex 9500 Anadex 9501 1195 1650 1650 799 1285 1285 —SEE THESE PRODUCTS AND MORE IN OUR SHOWROOM- PRICES CHANGE DAILY— CALL OR VISIT FOR CURRENT PRICING AUTOMATED EQUIPMENT, INC. 18430 WARD STREET, FOUNTAIN VALLEY, CALIFORNIA 92708 SYSTEMS GROUP 2800 Computer □ M 6400 Memory DMB-6400 Memory CPC 2813 CPU + 1/0 FDC2801 Control List Sell 5035 3595 760 585 995 735 460 365 465 370 SHU MICROPRO SOFTWARE List Sell Wordstar 495 330 Apple Wordstar 375 275 Spellstar 250 190 Mail merge 150 100 Datastar 350 250 Supersort 250 190 DISC CABLES Memorex 5 10 Verbatim $" 2D Verbatim 5" 2D Dysan 5" 2D RS-235 5 Cable RS 232 10' Cable Catif. and International (714) 963-1414 Toll Free. (800) 854-7635 ■IM ■■BUM Circle 44 on inquiry card. ACCOUNT REPORT DESCRIPTION Account #: 3281 name : Budget STATUS This account is not currently up to date. Last payment was made 12 months ago. ACCOUNT INFORMATION Balance Payment Amt Last Pmt $31,000.00 292.89 3.69 Figure 5: Standard methods of presenting text and numbers on the screen. Text is easier to read if left- justified. Numbers are easier to read if right-justified and aligned on the decimal point (if any). ever tried to count over to, say, the 15th character of a 40-character string, you know the problem. Elements of the string can be more readily located if you display the string as several short strings, (i.e., consisting of five or fewer characters) separated by spaces. (Better yet, find an explicit, uncoded method to pre- sent your information.) According to standard practice, text is normally justified to the left side of the screen or to a defined tab value. Numerical information is nor- mally justified to the right. Where the number of decimal places may vary on successive lines, decimal points on all lines should align at a particular tab value. These conventions are carry-overs from mainframe practice, where the availability of sophisti- cated formatting statements makes alignment easy. Justifying numbers to the right and aligning decimal points are more difficult with most micro- computer BASICs, although subrou- tines for performing these functions have appeared in publications, and most moderately skilled program- mers can write their own. Figure 5 il- lustrates conventional alignment of information on the display screen. Sequence Control Sequence control is the manner in which the operator controls the se- quence of program operations. In menu-driven programs, the operator exercises sequence control through menu choices. These let the operator select the subprograms he needs to do his job. An operator can exercise sequence control in many other ways. Control simply requires an interaction or ''dialogue" with the program. The menu-driven program permits a par- ticular type of dialogue. Other com- mon dialogue types are question and answer, query, program-like lan- guage, and action code. In question-and-answer dialogue the program displays a question and the operator responds with an answer. The expected answer is one of a limited set of alternatives, such as "yes" or "no." Example: Program asks whether output should be dis- played on video terminal or printer. Query dialogue is an extension of question and answer: a question is posed but the number of alternatives is large. Example: Program requests the number of the file it should dis- play. Program-like language dialogue uses a defined set of commands to control the program. Valid com- mands are usually brief mnemonic abbreviations of action words. Exam- ple: Command words used to control the Star Wars game. 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For more information, contact: In as.: ISE-USA P.O.Box 248 Lafayette, Indiana 47902 Tel: (317) 463-2581 In Germany: ISE-ADV/ORGA GERMANY Lipowskystr. 26 8000 Munich 70 Tel: (089) 776 023-4 In England: ISE-PACTEL Rochester House 33 Greycoat Street London SW1P2QF Tel: 01-828 7744 ISE-CEGOS Tour Chenonceaux 204. Rond-Point du Pont de Sevres 925 1 6 Boulogne Billancourt Cedex Tel: 620-61-04 In Switzerland and Austria: ISE-ADV/ORGA SWITZERLAND Mainaustrajte 1 7 CH-8008 Zurich Tel: (01) 32 02 70-1 Elsewhere: ISE-INTERNATIONAL P.O. Box 248 Lafayette, Indiana 47902 Tel: (317) 463-2581 P.O. Box 248 Lafayette, IN 47902 For more on one of our fine products, see page 314 126 April 1982 © BYTE Publications Inc As inevitable as evolution, Mainframe solutions at micro prices. A new era has begun. With computer prices down and five-year old mainframes, Professional demand was inevitable. Software unavailable. The solution: ISE. The new kind of computer company . ..offering mainframe-quality software at micro-software prices. For more information on this significant breakthrough, phone (317) 463-2581. Professionals know the difference. P.O. Box 248 Lafayette, IN 47902 Circle 261 on inquiry card. How to stay hot with the leading programming languages. 1 || System IWntoranc* V Diagnosticsn tor_Uuii«*n - ---| - ^ -^5\\H | _ ■* -*•' - ***3KZ?~ •• ^--^^0 When you're hot you're hot And SuperSoft's language series keeps you that way. Out front with the most advanced capabilities for microcomputer programming: SuperSoft's Language Series Ada* Required by the Department of Defense for all its programming, Ada is the language of the 80s. SuperSoft Ada is a native code, fully recursive two pass compiler which generates .COM" files. It currently supports most features of the standard Ada language, (requires 48k CP/M) Ada: $250.00. Manual only: $25.00. C Version 1.1 of SuperSoft's widely used C compiler has now been released. With this release SuperSoft's C, a two pass compiler which produces assembly code, now includes all the most widely used features of the C language, (requires 48k CP/M) C: $200.00. Manual only: $15.00. C for 8086: $500.00. LISP SuperSoft LISP is a complete implemen- tation of an EV-LISP type interpreter. It is fully recursive and also supports the much needed PROG functions. LISP for TRS-80 cassette: $75.00. (requires 16k level II) LISP for TRS-80 disk: $100.00. (requires 16k disk) LISP for CP/M: $150.00. (requires 32k CP/M) Manual only: $15.00. BASIC SuperSoft BASIC Compiler is a superset of Standard BASIC which accepts the most popular syntax and also supports many extensions to the language, (requires 48k CP/M) BASIC: $200.00. Manual only: $25.00. BASIC for Z8000: $500.00. FORTRAN IV and RATFOR The SSS FORTRAN Compiler is fast, efficient, and complete (full 1966 ANSI standard with extensions), (requires 32k CP/M, Z 80 only) FORTRAN: $275.00. RATFOR: $100.00. FORTRAN and RATFOR: $350.00. FORTRAN manual: $25.00 FORTH The production code of Stackworks FORTH (1977 FORTH Standard) is capable of compactness approaching and frequently smaller than the size of equivalent assembly code, (requires 48k CP/M) FORTH: $200.00. Manual only: $25.00. srSoft software available for virtually all CP/M systems. Please specify your system. Also Available From SuperSoft; System Maintenance Series Diagnostics II, Disk Doctor, System Checker Financial Planning Series Scratchpad, Data-vfew, Stats-graph, The Optimizer System Utilities Term II, Utilities Packs I & it, EHnk, Disk Edit, Encode/ Decode II, BCD Entertainment Series Nemesis, Dungeon Master, Anaiiza II Wbrd Processing Star-Edit, TFS Available from fine dealers everywhere, or directly from SuperSoft. UK and European Distribution: Digital Devices, 134 London Road, Southborough Kent, Tunbridge Wells, TN4 OPL, England. Tel. Tunbridge Weils (892) 37977/9 Telex. 95582. Japanese Distribution: ASR Corporation international, 3-23-8, Nishi-Shimbashi, Minato-Ku, Tokyo 105, Japan, Tel. (03)-437-5371, Telex. 0242-2723. Required by the Department of Defepse for Ada copyright protection: This compiler is presently an incomplete implementation of the Ada programming language; It is inteiided that this compiler will be further developed to enable implementation of the complete Ada programming ianguagerand then to be submitted to the Ada Joint Program Office for validation;' *Ada is a trademark of the Department of Defense (Ada Joint Program Office) CP/M registered trademark Digital Research SSS FORTRAN copyright Small Systems Services Unix registered trademark- BellLaboratories Circle 392 on inquiry card. FIRST IN SOFTWARE TECHNOLOGY P.O.Box 1628 Champaign, IL61820 (21 7) 359-21 12 Telex 270365 PROMPTING LEVEL SELECTION MENU Please select desired level of prompting: 1. Full 2. Partial 3. None Enter Choice # . Figure 6: Menu which allows the operator to choose the prompting level. Features like this accommodate operators who dif- fer in skill. Action code dialogue usually in- volves the use of specially defined and labeled function keys for calling up displays or programs. User-de- fined function keys are not widely available on microcomputers, but we will see more of them in the future. The new IBM Personal Computer has 15 or more user-defined function keys. Beside these methods, sequence control can be exercised in a number of other ways— in fact, via any chan- nels that permit the operator to enter data into the computer and receive feedback. Possibilities include track- ball, joystick, optical device, human voice, and whatever else creative minds can invent and implement. The Old Standby— the Menu-Driven Program In this article I cannot cover sequence-control design principles that apply to all dialogue types. For one thing, there isn't room. But more important, the research with many of these methods is limited, and I can offer few definitive recommenda- tions. For these reasons, I will focus on that old standby, the menu-driven program. Though its origin is trace- able to the earliest days of computing machinery, the menu-driven program remains the principal means by which people carry on dialogues with com- puters. Until people perfect ways of talking with computers, the' menu- driven program will probably remain the mainstay. There are good reasons for its popularity and success. First, it makes no demands on human mem- ory. Menu options are displayed on the screen and the operator picks the one he wants. This makes a menu- driven program easy to learn. Sec- ond, menus help the operator orient himself because they explicitly dis- play the available "roads" (sub- programs) from each "crossroad" (menu). Menu-driven programs have cer- tain drawbacks as well. Storing and generating menus cost memory and time overhead. Once familiar with a program, operators may find that layers of menus impede progress more than they help. For all that, the menu-driven pro- gram is a good vehicle for our discus- sion of sequence control because most people are familiar with it. Many of the design principles I will discuss in relation to it can be extended to other types of dialogues as well. Your menu-driven program should be self-explanatory. The operator should not have to refer constantly to a manual to figure out how to make something happen. Obviously, you cannot explain everything within the program, but you should provide screens that describe special se- quence-control features. For example, suppose that your program has several subprograms, each containing sub-subprograms, and so on, and that different program levels are ac- cessed through layers of menus. Sup- pose further that you have designed certain sequence-control features to shortcut some menus so that the ex- perienced operator can move quickly around to different parts of the pro- gram. Special features such as these should be explained within the pro- gram, either on separate screens which precede menus or, if the ex- planation is brief enough, on menus themselves. Your program will function, of course, without built-in screen docu- mentation. However, the operator will learn the intricacies of your pro- gram much more quickly if you do your explaining when and where he needs it — within the program itself. If the operators using your pro- gram will vary in skill level, attempt to build in features that will accom- modate skill growth. For example, let the operator select the level of prompting— full, partial, or none. This will help the inexperienced operator gain skill and confidence and save the experienced operator a lot of time. Make the choice of the prompting-level convenient, as shown in figure 6. Your program may have one menu or several, depending on complexity. If it is a complex program with many options, analyze how each sub- program will be used. Determine which subprograms are functionally related. Estimate how often each menu choice will be made. You may be able to make a very long menu into a number of short ones. Functional relationships and fre- quency of use of the subprograms are the two most important criteria to consider in designing a menu. List functionally related subprograms on the same menu. If possible, list fre- quently called subprograms on the same menu. If these requirements conflict, let functional relationships rule menu design. Avoid designing very long menus that contain a grab bag of unrelated options. This only makes sense if all programs are equal- ly likely to be called under all condi- tions. That is seldom the case. Make menu choices brief, explicit, and distinct from one another. To make up the label, consider exactly what each subprogram does and then label it accordingly. Use terminology consistently. For example, don't call subprograms that do essentially the same thing by dif- ferent names in the same program— don't call a program "edit" in one place and "modify/delete" in another. The menu itself has three essential parts; (1) title, (2) list of menu choices, and (3) prompt line. Some menus also contain a statement that directs the operator to "select one of the menu choices." This feature is useful to operators unfamiliar with computers and can be considered op- tional. 130 April 1982 © BYTE Publications Inc Circle 111 on inquiry card. %u G* 5 - v°? "DISCOUNT PRICING ON QUALITY PRODUCTS" FAST DELI VERY ON ALL MAJOR BRAND^^ACCESSORjES^^SOFT WAl ORDER TOLL-FREE! 1-800-854-2833>, ACCESSORIES Vic Datassette (6-pack) 68 Vic Disk Drive (6-pack) 489 Vic Graphic Printer 389 Vic 8K Memory Expander 52 Vic RS232C Interface , 43 Vic IEEE-488 Interface 84 Game Paddies 19 Joystick 19 Vic Super Expander 53 Vic Programmers Aid Cartridge 44 Vic Mon Machine Language Monitor 44 SOFTWARE Recreation Program Pack A 44 Home Calculation Program Pack A 44 Superslot 23 Avengers 23 Super Alien 23 Super Lander 23 Draw Poker 23 Vicatc 14 Viterm A 19 Vic Modem CALL 24K CALL VI Check 24 V P M 18 fly*. pppi FREE CATALOGUE 1-800-854-2833 CBM 8032 $1095 401 6N Pet 769 4032N Pet 969 SP9000 Super Pet 1 550 8032 1 095 8096 1 569 4022 Dot Matrix Printer 599 4040 Dual Disk Drive 985 8050 Dual Disk Drive 1299 2031 Single Disk Drive 529 8300P Letter Quality Printer 1790 IEEE-IEEE Cable 38 PET-IEEE 33 WordPro 3 Plus SOFTWARE 22g WordPro 4 Plus 329 Commodore Tax Package 399 Visicalc 149 BPI General Ledger 329 OZZ Information System 299 Dow Jones Portfolio 114 Pascal 229 Legal Time Accounting 449 Word Craft 80 289 Create-A-Base 249 CALL FOR COMPLETE SELECTION! 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ACTIVISION — Complete Selection HOW TO ORDER Ordering information: Phoneorders using VISA, MASTER- CARD, AMERICAN EXPRESS, DINERS CLUB, CARTE BLANCHE, bank wire transfer, cashier's or certified check, money order, or personal check (allow ten days to clear). Unless prepaid with cash, please add 5% for shipping. handling and insurance, (minimum 5.00) California resi- dents add 6% sales tax, We accept CODs, OEM's. Insti- tutions and corporations please send for a written quo- tation. All equipment is subject to price change and availability without notice. All equipment is new and complete with manufacturer's warranty (usually 90 days). Showroom prices may differ from mail order prices. L/mL/m^i^ IjJ^LJ] J Li^kJ >J I J Li T Li'Q 1 La » "msm ' (714) 579-0330 MAILTO:1251 BROADWAY EL CAJON, CA. 92021 ■-:■ Mm ■ Circle 32 on inquiry card. A0C4C9D3CBA0D5D4C9CCC9D4D9A0A4B5B0A0 A0 AO g Disk Utility » D3 for Apple DOS 3.3 D3 D4 rr CB § LOST PROGRAM g RECOVERY S C5 cc C5 |f you haven't D4 . I cs written over that C4 program accidental- Ad C6 ly deleted, this ^ software can re- C5 cover it for you. D3 AO A0 Also, it can A3 reorganize your disk cs and inform you of D8 -i. ci the remaining g space available. CE ^ And, it allows ci you to patch any H sector: display in af Hex and ASCII on 02 standard Apple M screen. w cc CI D9 A A6 D(3 CI D4 C3 C8 A0 D5 D4 C9 CC C9 D4 D9 A0 CD CI CE D5 C6 CI C3 D4 D5 D2 C5 C4 CI A0 ^ Menu driven and C2 C3 D9 cs easy for the novice a® £J while still efficient g ce for the professional. D3 H Compatible with g C4 M & R Superterm. D2 C9 A0 D3 C3 CB F or more information or CF D3 to place your order call: ^ | [208] 263-1213 £J D4 A0 £ Cost: $50 S A0 yVe pay first class postage and Cl A « insurance. You may use VISA or g~ A0 MasterCard. C p C9 TO ORDER: Send us your D4 D3 check, money order or credit card 07 CB number and expiration date. CI A< * Certified checks avoid clearance D2 o\ ANSWER Corporation ?{ D5 502 A North Second Ave. CF D3 Sandpoint, Idaho 83864 CC AO r AO A0A0C2D9A0CAC5D2D2D9A0D4C9C6C6D4A0A0 132 April 1982 © BYTE Publications Inc r\ """ MAIN MENU Select one of the following programs entering its number by 1. 2, 3. 4. 5. 6. ENTER DATA GENERATE REPORTS EDIT DATA BASE START NEW FILE PURGE FILE QUIT Enter Choice #_ V m ^> Figure 7: Menu showing the three essen- tial menu parts: title, list of choices, and prompt line. Some menus also have a directive to prompt operators unfamiliar with the system. Center the menu title at top of the display and put the word "menu" at the end of the title. If you are pro- viding the (optional) directive line, print this next, offset to the left, so that it is recognized as an instruction and not a title. Center the prompt and the data input field at the bottom of the screen. The prompt should be brief and explicit, for example, "ENTER CHOICE #," as shown in figure 7. Menu selection can be done in several different ways: by entering the number of a menu option, by entering a letter, by typing in the menu choice, and by moving a cursor to the choice. Typing in the menu choice label usually requires several keystrokes and should be avoided. Most microcomputer software is not set up to permit cursor selection of menu choices. The most common selection method is to type in a number or letter. In general, short menus should permit selection by letter — preferably the first letter of the choice label. (This can present problems if dif- ferent menu choices start with the same letter.) On longer menus, num- bered menu choices are more conve- nient. If you do use numbers, then any list of numbered items appearing on one of your display screens will resemble a menu. This may cause confusion. Minimize confusion by ti- tling menus as menus and titling other displays appropriately. Avoid num- bered items on nonmenu displays, if possible. If you are presenting a list of instructions, for example, precede each instruction by a bullet instead of a number. Conclusion This brief excursion into the world of human factors covered areas of in- terest to the average microcomputer programmer. Much more is written on the subject, and those interested should consult the references listed at the end of this article. Note that application of human- factors considerations to software design is immature as a technology and that much research still needs to be done. At present there is no single source to which the reader can refer to find all the important answers. (Martin's book is comprehensive but aimed primarily at the mainframe user.) Much of what is now available comes as technical reports that pre- sent recommendations cautiously labeled as ''preliminary" or "tentative" findings. In this article, I have attempted to congeal this somewhat indefinite material into a form that is useful to the average reader. Much has been left out because of inapplicability to microcomputers or because the material was of a specialized nature and would probably not be of in- terest. In general, what was presented is based on the references, although at some points I have condensed and simplified things. I hope that I have not distorted any author's intentions in the process. ■ References 1. Anacapa Sciences Inc. "Fundamentals ot Human Factors for Engineering and De- sign—Session 22: Human-Computer Interface Design" (classroom notes from seminar). Santa Barbara, CA: 1981. 2. Engel, $.£.,& Granda, R. E. Guidelines for Man/Display Interfaces, Technical Report TR 00.2720. Poughkeepsie, NY: IBM, December 19, 1975. 3. Martin, J. Design of Man-Computer Dialogues. Englewood Cliffs, NJ: Prentice- Hall, 1976. 4. Smith S. L. Man-Machine Interface: Re- quirements Definition and Design Guide- lines — a Progress Report, Project No. 572R. Bedford, MA: Mitre Corporation, February 1981. COMPUTERS INTERSYSTEMS DPS1. DPS1A. DPS2A CALL FOR PRICES DYN ABYTE List Less 30% ALTOS List . . . . Less 20% NORTHSTAR Horizons & Advantages CALL TELEVIDEO COMPUTER SYSTEMS CALL SUPERBRAIN 64K DD $2639 64K QD $2949 DSS-10MEG Hard Disk $3195 CROMEMCO CS-1 List $3495 OUR PRICE $3195 CS-2 List $4695 OUR PRICE $3549 CS-3 List $7995 OUR PRICE $6349 Z2H List $9995 OUR PRICE $7995 Tg§ttm I data I systems Z-89 List $2895 OUR PRICE $2099 TERMINALS TeleVideo Televideo 910C CALL 912C CALL 920C CALL 925C CALL 950C .CALL INTERTUBE $725 Emulator $725 OKIDATA MicrolineSO $359 Micro! me 82 A $469 Mtcrolme 83A $749 C.ITOH CALL FOR PRICES SOROC Soroc IQ120 $679 IQ130. $585 IQ135 $719 iQ135w graphics $789 IQ140 $995 HAZELTINE 1420 CALL 1500 SAVE 1510 CALL ZENITH Z19 $639 Prices quoted are for prepaid orders only, and reflect a cash discount. C.O.D.'s and chatge cards slightly higher. Most .terns in stock for immediate delivery, factory sealed Cartons w full factory warranty. NYS residents add appro- priate sales tax Prices do not include shipping. COD. orders require 25% deposit Prices subject to change without notice. PRINTERS CENTRONICS 749-1 PAR $699 739-3 SER $619 704-11 parallel $1569 704-9 (RS232) $1519 TI810 810 Basic $1289 810 Full Option $1599 820 RO Basic $1545 820 KSR Basic $1739 NEC 7710 (RS232) SERIAL $2395 7730 PARALLEL. $2395 Qume CALL FOR PRICE Diablo 630 RO $2049 1640 KSR $3495 1640 RO $3095 Paper Tiger 445G $739 560G $1099 Epson MX-80 MX-80FT MX 100 $465 $548 $745 DISK SYSTEMS MORROW Discus 2D $835 Dual Discuss 2D $1385 Discuss2 + 2 $1089 M 5 5meg Hard Disk $3750 M 10 10 meg Hard Disk $2999 M26 26 meg Hard Disk $3349 CORVUS 5 meg Hard Disk $3109 CORVUS 10 meg Hard Disk $4439 CORVUS 20 meg Hard Disk $5349 COMPUTERS WHOLESALE P.p. Box 144 Catnil lus, N.Y. 13031 Pnces subject to change without notice Circle 119 on' inquiry card. The Atari Tutorial Part 8: Generating Sound with Software The sound capabilities of the Atari 400 and 800 computers are influenced by the software technique used. Bob Fraser 1639 Martin Ave. Sunnyvale, CA 94087 The sound system in the Atari 400 and 800 microcomputers can be used in two basic ways: static and dynamic. Static sound generation is the simpler of the two. The program sets a few sound generators, turns to other activities for a while, and then turns them off. Dynamic sound generation is more difficult. The com- puter must continuously update the sound generators during program ex- ecution. For example: SOUND 0,120,8,8 generates a static sound, while: FORX = 0TO255 SOUND 0,X,8,8 NEXTX generates a dynamic sound. This article appears in slightly different form in De Re Atari, published by Atari Inc., and is reproduced with its express permission. Static Sound Although static sound is normally limited to beeps, clicks, and buzzes, there are exceptions. Two examples are the programs given last month as special effects in the sections on high- pass filters and 16-bit sound. Another way to obtain interesting effects is to use interference, as in this example: SOUND 0,255,10,8 SOUND 1,254,10,8 The strange effect is a result of closely phased peaks and valleys. Figure 1 shows two channels in- dependently running sine waves at slightly different frequencies and their sum. The sum curve shows the strange interference pattern created when these two channels are added. Figure 1 also shows that, at some points in time, the waves are assisting each other; at other points, they op- pose each other. Adding the volumes of two waves whose peaks coincide will yield a wave with twice the strength or volume. Similarly, adding the volumes of two waves while one is at maximum and the other is at minimum will result in a cancellation of both of them. On the graph of the sum curve, we can see this effect. An interesting project would be writing a program to plot interaction patterns of two, three, and four channels; the program would display graphs like that of figure 1. You might discover some unique sounds. The slighter the difference in fre- quency between the two channels, the longer the pattern of repetition. To understand this, draw some graphs similar to figure 1 and study the in- teraction. As an example, try the following BASIC statements: SOUND 0,255,10,8 SOUND 1,254,10,8 SOUND 1,253,10,8 SOUND 1,252,10,8 As the difference in frequency grows, the period of repetition decreases. 134 April 1982 © BYTE Publications Inc From CMC International, world's largest Intertec distributor... SUPERBRAIN and COMPUSTAR - YOUR CUSTOMERS WILL NEVER NEED ANOTHER SYSTEM! CMC International is the largest distributor in the world ot Intertec Data Systems products -the SuperBrain and CompuStar - Intertec's incredibly expandable microcomputers. 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We deliver. ^lPnATA TEC For Intormation Call (206)453-9777 sIls^aiMS To 0rder ' CaN To,,_free 1-800-426-2963 CMC A Division of Computer Marketing Corporation 11058 Main Street, Suite 220 Bellevue, Washington 98004 TELEX 152556 SEATAC SuperBrain and CompuStar are registered trademarks of Intertec Data Systems Corporation CP/M Is a registered trademark of Digital Research Circle 87 on inquiry card. BYTE April 1982 135 Minicomputer performance in Multi-user. Multi Tasking. Decision I™ memory man- agement hardware includes a memory map that is similar to the IBM 360f and IBM 370f It supports up to 16 tasks or 15 users and a supervisor without swapping. And, more with swapping. Each task or user enjoys complete memory protection and dynamic memory allocation. One task may be delegated as a supervisor to privileged system functions forbidden to ordinary tasks or users. Such functions (I/O calls, unauthorized memory access, etc.), will trap to the supervisor. If supervisory functions are not required the system can be configured for turnkey multi-user operation. Multi-purpose IEEE696/S-100. Decision I utilizes the Morrow Designs IEEE Standard S-1O0 Wunderbussf That means you can configure it to your specific applications. Add a floating point processor, add memory (to a full mega- byte), add I/O, add controllers... add boards from dozens of manufacturers. And S-100 has a major advantage over single-board computers: If a board goes down, you simply replace it. And keep running. If you want to expand your system. Add boards and terminals. An unmatched software base. Decision I runs on the M/OS™ operating system. M/OS sup- ports all system calls source compatibly with UNIX? Thus, UNIX programs will compile directly and UNIX documentation is almost totally applicable. Morrow CP/M® has been configured to run under M/OS and communicate with both CP/M and UNIX standard media for maximum portability. Languages available include BASIC, COBOL, FORTRAN, RATFOR, Pascal and C. That means Decision I offers you a software base unmatched in its price/performance arena. The OEM machine. A basic multi-user system at $5,225 includes the Decision I, 4 Mhz Z80A-based CPU, sophisticated memory IBM 360 and 370 are trademarks of IBM Corp. Wunderbuss is a registered trademark of Morrow Designs Decision I and M/OS are trademarks of Morrow Designs UNIX is a trademark of Bell Laboratories, Inc. CP/M is a trademark of Digital Research Corp. ION I a multi-user Microcomputer. boards, controllers and software allow you to configure your system your way... through a single supplier. The decision is yours. Compare the Decision jt, feature-for-feature with mini or microcomputers on the market today. Compare capabilities. Compare flexibility. Compare utility. Then, compare price. We think Decision I will change the way you think about microcomputer systems. Complete information? See your computer dealer. Or, write Morrow Designs. LOOK TO MORROW FOR ANSWERS. management hardware, CP/M 2.2, M/BASIC 5.2, 3 serial and 2 parallel I/O ports, 14 I/O slots with S-100 connectors, supervisor control in both hardware and software, 128K of RAM and two quad-density disk drives (800K) with DMA controller. Plus, cabinet (either desk-top or rack-mount), and power supply. The same system with 8" floppies and a full Megabyte of formatted storage costs $5,659. And, we offer OEM pricing. A better microcomputer. Whether you're build- ing a single or multi-user system, the Decision I offers you a hardware/software combination unmatched in the field. Decision I is not simply an improved 8-bit microcomputer. It's a breakthrough. In both computing power and price. Systems your way. Morrow Designs' full range of hard and floppy disk memory, add- in memory boards, I/O MORROW OESIGN5 5221 Central Avenue, Richmond, CA 94804 (415) 524-2101 Circle 284 on inquiry card. CHANNEL 1 CHANNEL 2 CHANNEL 1 CHANNEL 2 POSITIVE + NEGATIVE = ZERO NEGATIVE + NEGATIVE = DOUBLE NEGATIVE POSITIVE + POSITIVE * DOUBLE POSITIVE Figure 1: Complex waveform generation from the addition of waveforms. Listing 1: Using machine language to assist BASIC in generating multiple-note chords on the Atari 400/800. This demonstration program uses a short machine-language program placed in the BASIC string SIMUL$ (see lines 25 and 9999) to specify the frequency- and control-register values of up to four of the Atari sound generators. It is done quickly enough to make all the generators seem to start simultaneously (BASIC is too slow to do this). Note the use of the string SIMUL$ to store the machine-language program and the USR call in line 50 to execute it. 10 SOUND 0,0,0,0:DIM SIMUL$(16) 15 REM read in machine lang. program 20 RESTORE 9999:X = 1 25 READ Q: IF Q<> - 1 THEN SIMUL$(X) = CHR$(Q):X = X + l:GOTO 25 26 REM read and then play sound data 27 RESTORE 100 30 READ F1,C1,F2,C2,F3,C3,F4,C4 40 IF Fl = -1 THEN END 50 X = USR(ADR(SIMUL$),F1,C1,F2,C2,F3,C3,F4,C4) 55 FOR X = TO 150:NEXT X 60 GOTO 30 90 REM sound data 100 DATA 182,168,0,0,0,0,0,0 110 DATA 162,168,182,166,0,0,0,0 120 DATA 144,168,162,166,35,166,0,0 130 DATA 128,168,144,166,40,166,35,166 140 DATA 121,168,128,166,45,166,40,166 150 DATA 108,168,121,166,47,166,45,166 160 DATA 96,168,108,166,53,166,47,166 170 DATA 91,168,96,166,60,166,53,166 999 DATA -1,0,0,0,0,0,0,0 9000 REM 9010 REM 9020 REM this data contains the machine lang. program, 9030 REM and is read into SIMUL$ 9999 DATA 104,133,203,162,0,104,104,157,0,210,232,228,203,208,246,96, - 1 Dynamic Sound More complex sound effects nor- mally require the use of dynamic sound techniques. Three levels of dynamic sound generation are available to the Atari 400/800 pro- grammer: sound in BASIC, 60-hertz (Hz) interrupt sound, and sound in machine code. BASIC Sound BASIC is somewhat limited in its handling of sound generation. As you may have noticed, the SOUND state- ment negates any special AUDCTL setting. [The audio-control register AUDCTL was discussed in last month's installment of "The Atari Tutorial" . . . GW] This problem can be avoided by poking values directly into the sound registers, rather than using the SOUND state- ment. In addition, the use of BASIC to control sound generation is somewhat limited because of its slowness. If the program is not com- pletely dedicated to sound genera- tion, there is seldom enough pro- cessor time to do more than static sound or choppy dynamic sound. The only alternative is to temporarily halt all other processing while generating sound. Another problem can occur when using the computer to play music on more than one channel. If all four channels are used, the time separation between the first SOUND statement and the fourth can be substantial enough to make a noticeable delay between the different channels. The program in listing 1 solves this problem. SIMUL$ is a tiny machine- language program that pokes all four sound channels very quickly. A BASIC program using SIMUL$ can rapidly manipulate all four channels. Any program can call SIMUL$ by putting the sound-register values in- side the USR function as in line 50 of the demonstration program. The parameters should be ordered as shown, with the control-register value following the frequency- register value for each channel; this ordering is followed one to four times, once for each sound channel to 138 April 1982 © BYTE Publications Inc ■HHHHB^sa 8086 Super-micro 8 Mhz. - 16-bit - S-100 bus - 128K 70 nsec. RAM Computer Benchmarks - All systems running the same BASIC program. Manufacture - Model IBM 3033 Seattle Computer System 2 Digital Equipment PDP 11/70 Prime 550 Digital Equipment PDP- 10 IBM System 34 TEI System 48 Hewlett-Packard HP3000 Seattle Computer System 2 Alpha Micro AM-100/T Digital Equipment PDP 11/45 Data General NOVA 3 Ohio Scientific C4-P North Star Floating Point Radio Shack TRS-80 II Apple II + Cromemco System 3 Commodore Pet 2001 IBM 5100 Vector MZ * C - Compiler; I = Interpreter. Times (except for Seattle Computer) taken from August 1981 issue of Interface Age. Seattle Computer System 2 consists of 8 Mhz. 8086 CPU set, 128K of 70 nsec. static RAM, double- density disk controller, 22-slot TEI constant voltage mainframe, a cable for two 8' drives, and MS-DOS operating system (also called 86-DOS, IBM PC-DOS, Lifeboat SB-86). The system is fully assembled and tested and ready to run with the addition of disk drives (we can supply) and terminal. Price: $4185. 8087 Adapter also available. Class Operating Language Run Time System (Type*) (Seconds) Mainframe VS2-10RVYL Stanford BASIC 10 Micro MS-DOS Microsoft BASIC (C) 33 Mini n/a BASIC (I) 45 Mainframe PRIMOS BASIC V16.4 (I) 63 Mainframe TOPS- 10 BASIC (I) 65 Mainframe Release 05 BASIC (I) 129 Micro MAGIC 1.0 Microsoft BASIC (C) 178 Mini Time Share BASIC (I) 250 Micro MS-DOS Microsoft BASIC (I) 310 Micro AMOS 4.3a Alpha BASIC (SC) 317 Mini n/a BASIC (I) 330 Mini Time Share BASIC 5.32 517 Micro OS65D 3.2 Level 1 BASIC (I) 680 Micro NSDOS NorthStar BASIC (I) 685 Micro TRSDOS 1.2 BASIC (I) 792 Micro DOS 3.2 Applesoft II (I) 960 Micro CDOS 32K BASIC (I) 1074 Micro n/a Microsoft BASIC (I) 1374 Micro n/a BASIC (I) 1951 Micro n/a Micropolis BASIC (I) 2251 Call for location of our nearest dealer Software We have the following Microsoft high-level languages running under MS-DOS. • BASIC-86 Interpreter $400 • BASIC-86 Compiler $400 • Fortran-86 $600 • Pascal-86 $600 • Cobol-86 $900 • Macro-86 Assembler $300 Check for new additions 1114 Industry Dr. Seattle WA 98188 Information Hotline 206/575-1830 Circle 367 on inquiry card. 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BOX 35007 □ MINNEAPOLIS, IV1N 554350612-944-7907 140 April 1982 © BYTE Publications Inc be set. As a speed consideration, as well as a convenience, SIMUL$ allows you to specify sound for less than four channels (i.e., channels 1 through 3, channels 1 and 2, or just channel 1). Simply omit the unused parameters from the USR function. SIMUL$ offers another distinct ad- vantage to the BASIC programmer. The AUDCTL register is reset upon execution of any SOUND statement in BASIC. However, using SIMUL$, no SOUND statements are executed; thus, the AUDCTL setting is retained. Another method of sound genera- tion in BASIC is impractical. This method uses the volume-only bit of any of the four audio-control registers. Type in and run the follow- ing program: SOUND 0,0,0,0 10 POKE 53761,16: POKE 53761,31: GOTO 10 This program sets the volume-only bit in channel 1 and modulates the volume from to 15 as fast as BASIC can. Although it uses all the process- ing time available to BASIC, it pro- duces only a low buzz. 60-Hz Interrupt This technique is probably the most versatile and practical of all methods available to the Atari com- puter programmer. Precisely every 1/60 second the computer hardware automatically generates an interrupt. When this happens, the computer temporarily leaves the main program (the pro- gram running on the system — BASIC, Star Raiders, etc.). It then ex- ecutes an interrupt service routine, a small machine-language routine designed specifically for servicing these interrupts. When the interrupt service routine finishes, it executes a special machine-language instruction that restores the computer to the in- terrupted program. This all occurs in such a way (if done properly) that the program execution is not affected. In fact, it has no idea that it ever stopped I The interrupt service routine cur- rently resident on the Atari 400/800 Announcing trie Printing Breakthrough of the century: Smith-Corona TP-1 Text Printer LOW COSt Daisy Wheel Printer $ 845 oo • Microprocessor Electronics • serial or Parallel interface Simple, Reliable Mechanism ACT NOW: Limited Supply, low, low Cost Smith corona, one of the largest manufacturers of small printers in the world, gives a whole new perspective to printing with their electronic text printer— TP-1. The TP-1 is a microprocessor controlled, high quality daisy wheel printer. it produces perfectly formed, executive quality printouts at the speed of 120 words per minute. Typewriter quality printing at dot matrix prices. Simple, durable and dependable, TP-1 may be used with word processing systems, microcom- puters and most small business systems. 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Before the interrupt service routine returns to the main program, it can be made to execute any user routine — for example, your sound-generation routine. This is an ideal situation for sound generation since the timing is precisely controlled, and especially since another program can be executing without paying heed to the sound generator. Even more im- pressive is its versatility. Because it is a machine-language program, the interrupt sound program will lend itself equally well to a main program written in any language — BASIC, assembly language, FORTH, Pascal. In fact, the sound generator will re- quire few, if any, modifications to work with another program or even another language. A table-driven routine offers max- imum flexibility and simplicity for such a purpose. Table-driven refers to a type of program that accesses data tables in memory for its information. In the case of the sound generator, the data tables would contain the fre- quency values and possibly the audio-control-register values. The in- terrupt service routine would simply read the next entries in the data table and put them into their respective audio registers. Using this method, notes could change as often as 60 times per second, fast enough for most applications. Once such a program has been written and placed in memory (for example, at location 600 hexa- decimal, the beginning of the page of memory reserved for the user), you need to install it as a part of the 60-Hz interrupt service routine. This is accomplished by a method known as vector stealing. Direct control of sound registers with a dedicated machine- language routine opens new doors in sound generation. Memory locations 224 and 225 hexadecimal contain the address of a small routine called XITVBL (eXIT Vertical BLank interrupt service routine), which is designed to be executed after all 60-Hz interrupt pro- cessing is complete, restoring the computer to the main program as previously discussed. The following procedure shows how vector stealing can be used to in- stall your sound routine: 1. Place your program in memory (e.g., 600 hexa- decimal). 2. Verify that the last instruction executed is a JMP $E462 (since location E462 hexadecimal is the XITVBL routine, this will make the main program con- tinue). 3. Load the X register with the high byte of your routine's address (a 6 in this case). 4. Load the Y register with the low byte of your routine's address (a in this case). 5. Load the accumulator with a 7. 6. Do a JSR $E45C (to set loca- tions 224 and 225 hexa- decimal). Steps 3 through 6 are required to change the value of the pointer at locations 224 and 225 hexadecimal without error. The routine called is SETVBV (SET Vertical Blank Vec- tors), which simply puts the address of your routine into locations 224 and 225 hexadecimal. Once installed, the system works as follows when an in- terrupt occurs: 1. The computer's interrupt routine is executed. 2. The computer jumps to the program whose address is in locations 224 and 225 hexa- decimal, which is now your routine, 3. Your routine executes. 4. Your routine then jumps to XITVBL. 5. XITVBL restores the com- puter's state previous to the in- terrupt and makes it resume normal operation. GRAPHIC SOFTWARE GRAPHIC SOFTWARE FOR MICROCOMPUTERS — This self-teaching guide will show you how to write your own graphics software. 61 programs for 2D and 3D graphics: interactive input, translations, rotation, isometric views, perspective, scaling, stretching, clipping, surface intersections, shading, hidden line removal, tablet software, animation and more. Applications to science, engineering and business. "One of the most outstanding books on computer software"— A. Grund, U. Illinois; "The best book available on microcomputer graphics"— Creative Computing Feb, 1982. Book -$21.95; Disk-$18.95. ENGINEERING SOFTWARE ENGINEERING SOFTWARE FOR MICROS —A self- teaching guide to developing software for engineering applications of microcomputers. Emphasis is on combining graphics with engineering problem solving. Programs included to interactively create engineering drawings, store on disk file, recall, modify and merge. Other programs for simulation, mechanisms design, heat transfer, circuit analysis, optimizations and including Monte Carlo techniques. Programs for Fourier analysis display frequency spectra graphically. This is a valuable collection of modern engineering analysis software for students and professionals. Book-$28.50;Disk-$19.95. Books contain fully documented program listings in BASIC with theory and equations. Disks contain the same programs as the books but without documentation. When ordering disks, please specify APPLE II Plus48K DOS 3.3 or CP/M. 142 April 1982 © BYTE Publications Inc Circle 229 on inquiry card. [An elusive and infuriating "bug" may occur when a 60-Hz interrupt routine involving arithmetic opera- tions (ADC and SBC op codes) is used as part of a BASIC program. The Atari BASIC floating-point routines set the 6502 decimal flag and cause add and subtract operations to be done in binary-coded decimal (BCD) instead of binary. If the 60-Hz interrupt occurs during a BASIC floating-point operation, the inter- rupt routine will be in decimal — not binary— mode unless you execute a CLD instruction at the beginning of the routine. My thanks to Chris Crawford of Atari for pointing out this bug. . . . GWj If you do not wish to implement such a program yourself, one is available from the Atari Program Ex- change. The package is called IN- SOMNIA (Interrupt Sound Initial- izer /Alterer), It allows creation and modification of sound data while you listen and is accompanied by an inter- rupt sound generator that is table- driven and compatible with any language. For more information, con- tact the Atari Program Exchange, 155 Moffett Park Dr., POB 427, Sunny- vale, CA 94086. Machine-Code Sound Generation Direct control of sound registers with a dedicated machine-language routine opens new doors in sound generation. The technique is as follows: write a program similar to the 60-Hz interrupt routine in that it is table-driven. However, the only routine now being executed by the Atari is dedicated to sound genera- tion. By expending much more pro- cessor time on sound generation, you can produce higher-quality sounds. Consider, for example, the output of a typical 60-Hz interrupt music routine; its output will look something like figure 2a. The volume-only bit offers a tremendous capacity for accurate sound reproduction. Since much more processing time is available with a dedicated machine- language routine, you can change the frequency at very high speed during the note's playing time. For example, suppose you discover that whenever any piano key is struck it produces the characteristic sequence of fre- quencies shown in figure 2b. The graph in figure 2b is called the piano envelope. To simulate a piano, the idea is to apply the piano envelope very quickly to the "plain- vanilla" square-wave beep. The note is thus slightly modified during its playing time. For example, a piano simulation of the three notes in figure 2a would be modified to look like figure 2c. This is essentially the same sound produced by the standard music routine of figure 2a, only the (2a) F R E U E N C Y (2b) F R E Q U E N C Y (2c) 1 NOTE TIME r-r#- TIME Jft—i Jp—1 A^n TIME Figure 2: Complex waveform generation under computer control. Figure 2a shows a frequency -versus-time plot of three sim- ple notes generated by one of the Atari sound generators. If the complete resources of the computer are used to modulate the frequency (or other parameters) of the notes white they are be- ing played, the computer can produce highly complex sounds. For example, if we find that a frequency envelope such as figure 2b simulates the sound of a piano, the envelope can be superimposed on the generated notes of figure 2a to give a modified set of notes that has a graph like that of figure 2c. STRUCTURAL ANALYSIS SOFTWAl STRUCTURAL ANALYSIS ON MICROS -This self teaching guide contains a series of programs which calculate stresses and deflections in beams, plates, trusses and frames using conventional and matrix techniques. Theory, equations and program listings fully documented. Written for the^non-spectalist who wants to use his micro for structural analysis with minimum investment in time Use the programs as is or modify for your own applications. Book-$39.95;Disk-$19.95. DATA PLOTTING SOFTWARE DATA PLOTTING ON MICROS — A collection of programs to process and display all types of data: bar charts, stock market charts, engineering and scientific data, 3D views of surfaces, pie charts, sorting, filtering, running averages, curve fitting, and more. Application to business, engineering and science. All programs fully documented and keyed to theory. Use as is or modify for your own applications Book -$24.95; Disk -$19.95. To order, send check drawn on U.S. bank, money order in US funds, Visa or Mastercard number with expiration date to KERN PUBLICATIONS 1 90 Duck Hill Road, P. O 1029A, Duxbury, MA 02332 Add $2 per book 4th cl postage in US and Canada; $3 1 St cl or UPS in US; $4.50 1st cl Canada; $12 air Europe and Central America; $18 elsewhere. Call (61 7 J 934-0445 for faster delivery. PUBLICATIONS 190 Duck Hill Rd Duxbury.MA 02332 Circle 230 on inquiry card. April 1982 © BYTE Publications Inc 143 the Atari 8 Star Win $25,000 in cash, plus prizes and an ATARI STAR by entering your software in the ATARI* ASAP competition. ATARI is looking for some of the greatest software from the brightest stars in the software field. "And naturally, we re willing to re- ward you for it. Every three months, ATARI will be presenting ATARI STARS to the writers of software programs judged first, second and third place in the following categories: con- sumer (including entertainment, personal interest and develop- ment); education; home business (personal finance and record keep- ing); and system software. The de- cision of the ATARI judges is final. Quarterly prizes will be from $750 to $3,000 worth* of selected ATARI products and an ATARI STAR. The annual Grand Prize will be the coveted Super Star trophy and $25,000 in cash** To be eligible, your software idea must be submitted to and published in the ATARI Program Exchange cata- log. Submit your pro gram on the official entry form which we'll rush to you if you send in the attached coupon. The ATARI STAR Awards are in addition to the percentage of rev enues you will automat ically be entitled to as ATA fit PROGRAM ATARI PROGRAM ATAftr PROQKAM ATARI PROGRAM a result of sales of your software programs in the ATARI Program Exchange. If you're a star, ATARI wants to reward you. Send in the coupon today or call toll-free 800-538-1862, in California 800-672- 1850, and you could be the proud winner of an ATARI ASAP STAR Tro- phy, and some great ATARI prizes. *Based on manufacturer's sug- gested retail price. Taxes are the sole responsibil- ity of the winner. Void where pro- hibited by law. Winners will be notified by mail. ATARI employees and their families are not eligible. For more contest details, call the toll-free numbers.© 1981 ATARI, INC. Circle 42 on inquiry card. For more contest details, call 800-538- 1862, in California 800-672-1850. Send to: ATARI Software Acquisition Program, Dept. C1E, P.O. Box 427, Sunnyvale, CA 94086 Yes, I want to enter the ATARI ASAP com- petition. Please rush me my entry form. Name Add ress City State/Zip_ A ATARI f/J A Warner Communications Company We've Brought The Computer Age Home." Listing 2: A machine-language program that uses the waveform mode of the Atari 400/800 to generate tones with a sine wave amplitude envelope (tones normally produced by the Atari have a square-wave amplitude). 0100 0110 0120 0130 0140 0150 0160 0170 0180 0190 0200 0210 0220 0230 0240 0250 0260 0270 0280 0290 0300 0310 0320 0330 0340 0350 0360 0370 0380 0390 0400 0410 0420 0430 0440 0450 0460 0470 VONLY Bob Fraser 7-23-81 volume-only AUDC1-4 bit test routine AUDCTL = $D208 AUDF1=$D200 AUDC1=$D201 SKCTL = $D20F TEMPO MSC *=$B0 .BYTE 1 .BYTE *=*$4000 LDA #0 STA AUDCTL LDA #3 STA SKCTL LDX §0 LOO LDA #0 STA $D40E ; disable vertical blank interrupt STA $D20E ; disable nonmaskable interrupts STA $D400 ; disable screen DMA LDA DTAB,X STA MSC 0480 LDA VTAB,X 0490 L0 LDY TEMPO 0500 STA AUDC1 0510 LI DEY 0520 BNE LI 0530 0540 dec most significant counter 0550 DEC MSC 0560 BNEL0 0570 0580 0590 new note 0600 0610 INX 0620 CPXNC 0630 BNE LOO 0640 0650 wrap note pointer 0660 LDX#0 0670 BEQ LOO 0680 0690 ; 0700 NC .BYTE 28 ; note count 0710 ; 0720 , table of volumes to be played in succession 0730 VTAB . 0740 .BYTE 24,25,26,27,28,29,30,31 0750 .BYTE 30,29,28,27,26,25,24 0760 .BYTE 23,22,21,20,19,18,17 0770 .BYTE 18,19,20,21,22,23 0780 ; 0790 ; this table contains the duration of each entry above 0800 DTAB 0810 .BYTE 1,1,1,2,2,2,3,6 0820 .BYTE 3,2,2,2,1,1,1 0830 .BYTE 1,1,2,2,2,3,6 0840 .BYTE 3,2,2,2,1,1 notes now have a piano tone and they sound much prettier than just un- modulated beeps. Unfortunately, all other processing had to be sacrificed to get that piano tone. The sound channel is no longer updated only once every note; it is now done perhaps 100 times within the note's duration. Volume-Only Sound As indicated earlier, the AUDCn volume-only bits aren't of much use in BASIC. This is due entirely to the fact that BASIC is too slow to effec- tively use them. However, this is not the case with machine language. As mentioned last month, the volume-only bit of the AUDCfi registers offers a tremendous capacity for accurate sound reproduction. True waveform generation (within the time and volume resolution limits of the computer) is made possible with this bit. Instead of just putting a piano flavor into the music, you can now make it closely replicate a piano sound. Unfortunately, it can never precisely duplicate an instrument. Four bits (16 values) is not enough volume resolution for true high- quality work. Nevertheless, the technique does generate surprisingly good sounds. The program in listing 2 demonstrates the use of one of the volume-only bits. If you have an assembler, type it in and try it. Sur- prisingly, speed is not really a prob- lem here. The wave has almost sixty steps, and the program can still be made to play the wave at up to 10 kilohertz. Remove lines 390 through 410 and try the program once more. It will sound quite broken up. The cause is the 60-Hz interrupt discussed in the previous section. You can actually hear the interrupts taking place since all sound stops during that time. Line 410 disables screen DMA (direct memory access), By disabling screen DMA, the ANTIC chip within the Atari 400/800 no longer "steals" time from the 6502 processor to get data from screen memory in time to display it on the video display. This is why the screen goes to a solid background color when the program is executed. Disabling screen DMA serves two purposes: to speed up the 6502 processor and to make the tim- ing consistent, since screen DMA steals cycles at odd intervals. 146 April 1982 © BYTE Plications Inc get on Irah Get irah 5Va" & 8" Floppy Drives ■II 1 ** "««.T. 0(10 TRAK Drive Systems are ready to plug in and use- complete with power supply and cable. TRAK — the way to go in floppy disk drives. Whether you are just buying your computer system, adding to it, or up-dating it— make it TRAK. TRAK features the finest industry-standard 5W and 8" drives, custom compact packaging, custom power sup- plies, ventilating fans with multi-drives and unique control facilities for your convenience and protection. Complete control is yours with deluxe TRAK Sys- tems. System control panels feature lighted "Sentinal" power switch so you always know when your TRAK drive is powered up. And individual "Protector" (write-protect) switches guard your stored information. TRAK offers you the widest choice— singles or multi-drives— 5Vi" or 8"— double sided— single/double densities— 3 to 8 ms access— from 125 K-Bytes to 4.8 Meg- abytes storage— choice of colors (office brown, silver gray or oyster)— optional door locks, front bezels, write-protect switch, extender card, optional 220V/50 Hz power supply for international use— and more. System compatibility. TRAK drive systems are com- patible with more than just one or two popular computer systems. TRAK drives are compatible with Apple II®, TRS-80®, IBM, Xerox, Heath/Zenith and other micros and minis. And more compatible systems are added continuously. Circle 451 on inquiry card. TRAK is committed to making a significant contribution to the world-wide computer industry by providing the latest products at the best prices. We invite you to join us in this common goal and get on TRAK. For price, order information and the name of your nearest dealer call TRAK toll-free. 1-800-323-4853 (in Illinois call collect 1-312-968-1716). ||^3L4 Microcomputer Corp. II DlT 1511 OgdenAve. Downers Grove, IL 60515 TWX 910-222-1848 Distributorships, dealerships available. International and OEM inquiries invited for TRAK drives, cabinets, power supplies and computer systems. New TRAK products coming soon. 5%* & 8" Slimline floppy drives, SVk" & 8" Winchester systems, multi-user networking, spe- cial Controller and host system adaptor boards. INTRODUCTORY FACTORY REBATE {$25 Buy from your TRAK dealer, then mail copy ^-^ of sales receipt with TRAK serial number and this coupon to TRAK. We will rebate $25 direct to you as our way of welcoming you to the TRAK drive family. Name __ A dd re ss City .State^ Zip. Offer expires May 30, 1982. Limit one rebate per customer. Offer void where prohibited. J ® TRS-80 is a registered trademark of Radio Shack, a Tandy Company ® Apple II is a registered trademark of the Apple Computer Company PRINTERS Epson MX-80 or MX-80 FT CALL Anadex 9501 w/2K Butler , 1349 C, Hon Starwrlter25 CPS dalsywheel 1449 C. Itoh Starwrlter 45 CPS daisywheel 1649 Epson MX-70 CALL Epson MX-80 & MX-80 FT CALL Epson MX-100 CALL NEC 8023 Impact Dot Matrix 629 NEC Spinwriters (Latest models) CALL Paper Tiger IDS-460G w/graphics 899 Paper Tiger 1DS-560G w/graphics 1099 Qume Spring Daisywheels (Latest models) CALL Diable 630 Dalsywheel 40 CPS 1795 VIDEO MONITORS Amdek/Leedex Video 100 12" B&W 129 Amdek/Leedex Video 100G 12" Green Phosphor 149 Amdek (Hitachi) 13" Color w/audto output 389 NEC 12" Green Phospher Display JB-1 201 M CALL NEC 12" Lo-Res Color Display CALL NEC 12" Hi-Res RGB Color Display CALL Sanyo 9" B&W Display 185 Sanyo 9" Green Display CALL Sanyo 12" B&W Display 269 Sanyo 12" Green Phospher Display 285 Sanyo 13" Color Display 449 Zenith 12" Green Phospher Display 139 ZENITH 12" GREEN $139 IBM ?***$£Ff ACC ESSO R I ES BY TECMAR 256 Dynamic Ram Card Hi-Speed Parallel I/O Card G *g Hi-Speed Serial I/O Card ™L Real-Time System Clock .!"' Card Expansion Chassis PKiuta Ordering Information; Phone orders using VISA, MASTER- CARD, AMERICAN EXPRESS, DINER'S CLUB, CARTE BLANCHE, bank wire transfer, cashier's or certified check, money order, or personal check (allow ten days to clear). Unless prepaid with cash, please add 5% for shipping, handling and insurance (minimum 5.00). California residents add 6% sales tax. Foreign customers please call or write for shipping information and charges. OEM's, In- stitutions and corporations please send for a written quotation. All equipment is subjecct to price change and availability without notice. All equipment Is new and com- plete with manufacturer's warranty (usally 90 days). Showroom prices may differ from mall order prices. Send Orders to: GOOODtpQaOQtfS Mailorder 8338 Center Drive La Mesa, California 92041 VIO20 $249 *On all prepaid cash orders • Continental US Only APPLE ll ACCESSORIES VIC ACCESSORIES 8K Ram Cartridge for VIC-20 $50 3K Ram Cartridge for VIC-20 $34 Superslot $24 Super Alien $24 Jupiter Lander $24 Draw Poker $24 VIC Software 6 pack 'A' $49 VIC Software 6 pack 'B' $49 Datasette Cassette I/O Unit $69 VIC IEEE-488 Interface $79 Vicmon Machine Lang Monitor $47 VIC Super Expander $54 VIC RS232C Terminal Interface $39 Voice Synthesizer CBM/PET $319 Pgrm Char Set/Game Graphics ED $13 3D invaders $31 Spiders of Mars $39 Outworld $32 Satellites and Meteorites $39 Alien Blitz $32 RS-232 Communicator Interface $40 18 In. Communicator Cable M/M $13 36 In. Communicator Cable M/M . $15 3K RAM Expander for VIC-20 $65 8K RAM Expansion for VIC-20 $99 VIC-20 Reference Card $4 VICTermA $16 Vicalc for VIC-20 $11 VIC Portfolio Mgmf. (VPM) $19 VICHECK $19 PAC It In $15 Amok $15 Don't Fall $11 Simon $7 Blastoids $16 Superadditon $7 Supersubtraction $7 Skymath $12 Space Division $12 Long Division $12 Super Hangman $17 BK ROM/RAM 25 Alien Blitz $19 Globber $19 The Alien (Req. 6K memory) $19 Invader Fall (Req. 6K memory) $17 StarWars $13 3D Maze $11 Breakout $11 Carom $11 Raceway $11 LazerWar $14 Dragon Maze $13 Shape Matcher $9 Doggy Maze $9 16K RAMBOARD by ConComp for Apple II Computers FOR ONLY 16K RamBoard by ConComp Industries 99 Hayes Mlcromodem II 299 Hayes Smartmodem 369 Hayes Chronograph 199 Novation Apple-Cat 339 Novation Cat Modem 169 Novation Expansion Mod 39 Novation Handset 29 Novation BSR 19 Vldex Videoterm 80 column card 249 Vldex Keyboard Enhancer (Rev. 6) 115 Vldex Keyboard Enhancer (Rev. 7) 99 Videx Keyboard Enhancer II (Rev. 7 & up) 129 Vldex Switchplate 15 Videx Soft Video Switch 29 Z-80 Softcard by Microsoft 299 Applesoft Compiler 149 Typing Tutor II 20 Microsoft Adventure 25 Olympic Decathalon 24 16K RamCard by Microsoft 159 Thunderclock clock/calender card 1 29 Thunderclock X-10 Inter/Scheduler 49 Smarterm 80 col card 299 Corvus Winchester Disk Drives CALL ALF 3 Voice Music Card 199 ALF 9 Voice Music Card 149 Alphasyntauri keyboard system CALL Lazer Lower Case + 55 Lazer Keyboard Plus + 99 23 Key Numeric Keypad by Keyboard Co 120 Joystick by Keyboard Co 45 6809 CPU Card (The Mill) by Stellation 319 AIO Serial & Parallel Interface by SSM A&T 189 DB Master by Stoneware 189 Music System (16 voices) 299 A/D + D/A Interface 279 Expansion Chassis (8 slots) 569 lntrol/X-10 Controller card 169 Clock/Calendar Card 225 CPS Multifunction Card .175 Supertalker SD-200 159 Romplus + card 135 Romwriter card 149 Symtec Hi-Res Light Pen 210 Sup-R-Fan 45 Sup-RTerminal 329 SVA ZVX4 Megabyter 8" Disk Controller 649 SVA 2 + 2 Single Den. 8" Disk Controller 345 Speechlink 2000 by Heuristics 249 Versawriter Digitizer Tablet 229 Asynchronous Serial Interface card by CCS 1 39 Centronics Parallel Interface card by CCS 119 VisiCalc version 3.3 169 VIsiFile (NEW data base manager) 199 VisiTrend/VlsiPlot 219 VisiDex 169 VisiTerm 99 Desktop Plan II 169 Wordstar (Apple 80 col version) 299 VislPak (Calc, Trend, Plot, File) 550 Easywriter Word Processor 199 Tax Preparer '81 version 89 Real Estate Analyzer 129 Creative Financing 139 Personal Filing System (PFS) 79 PFS...Report 79 Datastar (Apple II ■ 80 col) 249 Spell Star (Apple II • 80 col) 219 Super-sort (Apple II - 80 col) 1 79 Peachtree Accounting Software CALL BPI Accounting Software CALL Systems Plus Accounting Software CALL CALL OR WRITE FOR FREE CATALOG NO RISK* MAIL ORDER DISCOUNTS *Call for Details ORDER TOLL FREE In California and [H I v Telex 6954100 Beta CCMO Circle 126 on inquiry card. E3 commodore CBM Business Computer CALL FOR BEST PRICES 73 Key Typewriter Style Keyboard 80 x 25 Column/Line Video Display Integrated ST Green Phosphor Monitor Standard Inverse & Overstrike Characters Full Screen editing capability Built-in Built-in Parallel I/O Port IEEE-488 Bus Interface Capability Standard! 2 Cassette Ports 18K ROM BASIC (Version 4.0) 9 Digit Floating Point Binary Arithmetic Sophisticated Disk & Tape Handling Software We couldn't tell you all the things the Commodore CBM system could do for your home or office, but think about hiring a secretary, an accountant, and a financial advisor all for the price of a Commodore CBM 8000 Computer! Just add the Commodore 4040 or 8050 dual floppy disk drive, and a printer of your choice, and you've got a fully in- tegrated system, ready to bring the computer revolution into your home or business! Start your revolution now at Consumer Computers. MASS STORAGE DISK DRIVES AVAILABLE ACCOUNT- ING SOFTWARE AND SPECIALIZED MARKET SOFT- WARE TOO! Personal Computer CALL FOR BEST PRICE Introducing the Commodor PET! All the things you need to start computing today are built right in. Things like 18K PET BASIC, 9" Green Phosphor Video Monitor, 74 key pro- fessional keyboard, numeric keypad, and more. As if this weren't enough, the PET comes has a parallel I/O port that is just waiting tor a printer, and the industry standard IEEE-488 bus for expansion. 40 x 25 Column/Line Video Display Integrated 9" Green Phosphor Monitor Standard Inverse & Overstrike Characters Full Screen editing capability Built-in Built-in Parallel I/O Port IEEE-488 Bus Interface Capability Standard! 2 Cassette Ports 18K ROM BASIC (Version 4.0) 9 Digit Floating Point Binary Arithmetic Sophisticated Disk & Tape Handling Software Other PET accessories and equipment available at great prices. At Consumer Computers we're experts in the business of selling computer products by mail. We have become one of the leaders not only because our prices are better, but because of the reputation we've worked hard to earn. Over the years we have learn- ed what you, the customer, want and need from a mail order company, if we offer any merchandise that you're in the market for, you should seriously compare what we have to offer over the others. Here are just a few of the reasons. Our helpful salespeople are prepared to meet any currently advertised price on anything we sell (call for details. ..it's Toll Free!). We pay shipping and insurance charges on prepaid cash orders (with destinations in the continental US). We ac- cept major credit cards for your conve- nience. If the product you receive is defec- tive, even up to 30 days after you purchase it, we'll repair or replace it and pay for ship- ping back to you. Consumer Computers carefully selects the hardware and software it offers to in- sure that quality is maintained in everything we sell. Our attention to quality is why we can stand behind our policy, because we stand behind our products. You'll never regret becoming a member of our growing customer family. You have our word. SEC Microcomputer r i I IffflMJli ■jfiSf f c cara™ / tiMitHiHuitmtt mimmmvYvvxv \ A ATARI ATARI 800 16K CALL FOR BEST PRICE Atari 400 W/16K 349 410 Program Recorder 65 810 Disk Drive 449 825 80 col. 7x8 Dot matrix impact printer 699 822 40 col. Quiet Thermal Printer 349 850 Interface Module 159 Atari 16K Ram Module 69 Axlon Ramcram 32K Module 189 Asteroids, Missile Comand and Star Raiders 35 ea. CALL FOR BEST PRICES If you're considering a computer, consider this: 4 Mhz Z-80A Operation 80 or 40 column modes STANDARD Built-in Centronics printer port Full ASCII keyboard with Shift lock Real Time Clock STANDARD RGB Color Output Mixed text and graphics Numerica Keyboard STANDARD CP/M Compatibility 5 programmable Function keys 24K Microsoft NBASIC in ROM with enhanced color graphic commands The NEC PC-8001A has all these features and much more. Expandibility you want, expandability you get. Through the use of the PC-8012A I/O unit, total system RAM can be extended to 160K. The PC-8031 Dual Disk Drive puts 286K of floppy disk storage at your comand. The NEC PC-8001A has so many things that are options on other computers built right in that you may never have to buy another accessory! The quality that the NEC name has come to sand for has been built-in, too. Compare the competition, and then call Consumer Com- puters for the NEC PC-8001. NEC COMPATIBLE SOFTWARE CP/M Operating system with graphics control CALL SUPERCALC Financial & Scientific Modeling (requires CP/M) CALL WORDSTAR Word Processing System {requires CP/M) CALL SYSTEMS PLUS Complete Accounting System (requires CP/M) CALL MICROSOFT BAStC-80 (requires CP/M) CALL MICROSOFT FORTRAN-80 (requires CP/M) CALL MICROSOFT COBOL-80 (requires CP/M) CALL consumer computers rder ORDER TOLL-FREE — 800-854-6654 In California and outside Continental U.S. 714-698-8088 *CalI for Details Please refer to ordering instructions on preceding page. Circle 127 on inquiry card. TIME Figure 3: An amplitude-versus-time graph of the sine wave sound produced by listing!. JONATHAN WINTERS COULD BE YOUR SALESMAN OF THE YEAR. . . ... if you sell small computers, word processing systems, software, media and supplies or computer services. COMPUTER SHOWCASE EXPO is coming to these cities in 1982 Because Johnny is our top salesman for COMPUTER SHOWCASE EXPO-a new concept in end-user computer shows. These sales events cater to your most serious prospects— small businessmen, doctors, lawyers, accountants, educators— and personal computerists excited about putting computer power to work at home. How does Johnny bring in the buyers? He is featured in an all out media blitz— • Prime Time TV • Drive Time Radio • High Visibility Newspaper Ads • Targeted Direct Mail You've never seen an end-user computer show promoted like COMPUTER SHOWCASE EXPO— because it's never been done before. And you've never seen buyers at an end- user show before like you'll see at COMPUTER SHOWCASE EXPO! But don't take our word for it. Here's what exhibitors said: AMERICAN COMPUTER NETWORK— "Our average configuration is about $42,000. We sold about 20 systems and probably have 300 good leads to follow. " RADIO SHACK— "100% most successful business show we ever attended." ALTOS COMPUTERS-" Very enthusiastic and serious buyers. The most professional computer show ever produced in San Francisco..." Marcn25-27 • Georgia World Congress Center ST, LOUIS April 15-17 • A.J. Cervantes Convention Center BOSTON April 15-17 • Commonwealth Pier Exhibition Hall April23-25 • Miami Expo/Center ANAHEIM May 7-9 • Anaheim Convention Center NEW YORK September 23-25 • New York Coliseum SAN FRANCISCO September 30-October 2 • Brooks Hall October 28-30 • Miami Expo/Center CHICAGO November 4-6 • McCormick Place LOS ANGELES November 18-20 • Los Angeles Convention Center So if you want Jonathan Winters on your sales force, write or call today for information on COMPUTER SHOWCASE EXPO. Call toll-free (800) 225-4620 Ask for Fred Stern (In Massachusetts, (617) 879-4502) fv/fTHE INTERFACE GROUP PO Sox 927, 160 Speen Street, Frarningham, MA 01701 (617) 879-4502, Outside Mass (800) 225-4620 Producers of INTERFACE FEDERAL DP EXPO COMDEX COMDEWSPRING COMDEX/EUROPE THE COMPUTER SHOWCASE EXPOS. In this demonstration program, the sound created is a close approxima- tion to a sine wave. A graph of the waveform is given in figure 3. The Role of Sound in Programs This article and last month's install- ment of "The Atari Tutorial" have discussed the technical aspects of sound generation with the Atari 400 and 800 computers. However, the programmer must also understand the broader role of sound in the com- plete software package. Moviemakers have long under- stood the importance of mood-setting background music. The recent Star Wars movies by George Lucas are ex- cellent examples. When Darth Vader enters the room, you immediately fear and hate him because of the menacing background rhythms ac- companying his entry. You know to gleefully applaud when Luke Skywalker saves Princess Leia because gallant music plays in the background. Likewise, horror films can frighten you merely by playing eerie music, even though the action may be completely ordinary. Tatio America's Space Invaders program for the Atari 400/800 issues a personal threat to the player with its echoing stomp. As the tempo in- creases, knuckles whiten and teeth grind. When you fire a photon torpedo in Atari's Star Raiders game, the computer gives you a "launch" sound that decreases in frequency as the torpedo speeds away from you. The effective use of sound can in- crease your involvement with a game or other program. Impressionistic sounds affect our subconscious and our state of mind. This may be due to the fact that sounds, if present, are continuously entering our mind whether or not we are actively listening. Visual inputs, on the other hand, require the user's attention. If we are distracted from the TV set, we cease to concentrate on the picture and the image leaves our mind. Sound therefore offers the programmer a direct path to the users' minds — bypassing their thought processes and zeroing in on their emotions. ■ 150 April 1982 © BYTE Publications Inc Circle 213 on inquiry card. In this age of runaway inflation... Look what $825 will buy The ideal input device for the small system user. Hi rJ S^lAm** /JES3 £££ wo «,* HH © Available with stylus or optional cursor. The HIPAD™ digitizer Inexpensive input to your computer The HIPAD™ digitizer can be used for both converting graphic information into digital values and as a menu. Utilizing either the stylus or the optional cursor, the operator can input graphic data into the computer by locating individual points on the digitizers 11" x 11" (28cm x 28cm) active area. In the "stream mode" a contin- uance of placements of coordinate pairs may be input. Not a kit, the HIPAD™ comes complete with both RS-232-C and parallel interfaces and has its own built-in power source. The origin is completely relocatable so coor- dinates may be positive or minus for a true reference value and oversized material may by input by simply resetting the origin. Accurate positional information, free form sketches, even keyboard simulation All can be entered using the multi-faceted HIPAD™ digitizer. Its capabilities and low price make the UL listed HIPAD™ a natural selection over keyboard entry, inac- curate joysticks, or expensive approximating light pens. It's perfect for inputting isometric drawings, schematics, X-rays, architectural drawings, business graphs, and many other forms of graphic information, as well as creating your own graphics. Use it with Apple II™ , TRS-80 Level II™, PET™ or other popular computers The HIPAD's™ built-in RS-232C and parallel 8 bit interfaces make it all possible. (For Apple II order DT-1 1 A, for TRS-80 or PET order DT-1 1). Furthermore, you get English or metric scaling, data format (Binary/BCD/ASCII), selectable baud rates, and resolution of either .005" or .01". For complete information, contact Houston, Instrument, P.O. Box 15720, Austin, Texas 78761. (512) 835-0900. For rush literature requests, outside Texas call toll free 1-800-531 -5205. For technical information ask for operator #5, in Europe contact Houston Instrument, Hochesterlaan 6, 8240 Gistei, Belgium. Phone 059/27-74-45. Telex Bausch 81399 Available with optional display. *U.S. Suggested retail price TM HIPAD is a trademark of Houston Instrument TRS-80 is a trademark of Tandy Corporation APPLE is a trademark of Apple Computer Inc. PET is a trademark of Commodore Business Machines, Inc. Circle 195 for literature. Circle 196 to have representative call. INSTRUMENTS & SYSTEMS DIVISION Tbgether...we'll create lomoiTDw BAUSCH & LOMB (W) Introducing the Sinclair ZX81 the If you're ever going to buy a personal computer, now is the time to do it. The new Sinclair ZX81 is the most powerful, yet easy-to-use computer ever offered for anywhere near.the price: only $149.95* completely assembled. Don't let the price fool you. The ZX81 has just about everything you could ask for in a personal computer. »A breakthrough in personal computers The ZX81 is a major advance over the original Sinclair ZX80-the world's largest selling personal computer and the first for under $200. In fact, the ZX81's new 8K Extended BASIC offers features found only on com- puters costing two orthree times as much. Just look at what you get: ■ Continuous display, including moving graphics ■ Multi-dimensional string and numerical arrays •Plus shipping and handling. Price includes connectors for TV and cassette, AC adaptor, and FREE manual, ■ Mathematical and scientific functions accurate to 8 decimal places ■ Unique one-touch entry of key words like PRINT, RUN and LIST ■ Automatic syntax error detection and easy editing ■ Randomize function useful for both games and serious applications ■ Built-in interface forZX Printer ■ 1K of memory expandable to 16K The ZX81 is also very convenient to use. It hooks up to any television set to produce a clear 32-column by 24-line display. And you can use a regular cassette recorder to store and recall programs by name. If you already own a ZX80 The 8K Extended BASIC chip used in the ZX81 is available as a plug-in replacement for your ZX80 for only $39.95, plus shipping and handling— complete with new key- board overlay and the ZX81 manual. So in just a few minutes, with no special skills or tools required, you can upgrade your ZX80 to have all the powerful features of the ZX81. (You'll have everything except continuous dis- play, but you can still use the PAUSE and SCROLL commands to get moving graphics.) With the 8K BASIC chip, your ZX80 will also be equipped to use the ZX Printer and Sinclair software. Order at no risk** We'll give you 10 days to try out the ZX81. If you're not completely satis- fied, just return it to Sinclair Research and we'll give you a full refund. And if you have a problem with your ZX81, send it to Sinclair Research within 90 days and we'll repair or replace it at no charge. "Does not apply to ZX81 kits. NEW SOFTWARE:Sinclair has published pre-recorded pro- grams on cassettes for your ZX81, or ZX80 with 8K BASIC. We're constantly coming out with new programs, so we'll send you our latest software catalog with your computer. ZX PRINTER: The Sinclair ZX Printer will work with your ZX81, or ZX80 with 8K BASIC. It will be available in the near future and will cost less than $100. 16K MEMORY MODULE: Like any powerful, full fledged computer, the ZX8i is expand- able. Sinclair's 16K memory module plugs right onto the back of your ZX81 for ZX80, with or without 8K BASIC), Cost is $99.95, plus shipping and handling. ZX81 MANUAL: The ZX81 comes with a comprehensive 164-page programming guide and operating manual de- signed for both beginners and experienced computer users, A $10.95 value, it's yours free with the ZX81. ^1 XI 99 95 personal comp iter. \ ore \ mi Introducing theZX81kit If you really want to save money, and you enjoy building electronic kits, you can order the ZX81 in kit form for the incredible price of just $99.95* It's the same, full-featured computer, only you put it together yourself. We'll send complete, easy- to-follow instructions on how you can assemble your ZX81 in just a few hours All you have to supply is the soldering iron' How to order Sinclair Research is the world's larg- est manufacturer of personal computers. The ZX81 represents the latest technology in microelectronics, and it picks up right where the ZX80 left off. Thousands are selling every week. We urge you to place your order for the new ZX81 today. The sooner you order, the sooner you can start enjoying your own computer. To order, simply call our toll free number, and use your MasterCard or VISA. To order by mail, please use the upon. And send your check or money order. We regret that we cannot accept purchase orders or C.O.D!s. CALL 800-543-3000. Ask for op- erator #509. In Ohio call 800-582-1364. In Canada call 513-729-4300. Ask for operator #509. Phones open 24 hours a day, 7 days a week. Have your Master- Card or VISA ready. These numbers are for orders only. For information, you must write to Sinclair Research Ltd., 2 Sinclair Plaza, Nashua, NH 03061 ■ ■ ■ indair - *:— «, *WK& / y *m r f Memory Module (for ZX81 or ZX80) PRICEf QTY. AMOUNT ZX81 ZX81 Kit 8K BASIC chip (for ZX80) Shipping and Handling $149.95 99.95 39.95 99.95 4.95 TOTAL $4.95 MAIL TO: Sinclair Research Ltd., One Sinclair Plaza, Nashua, NH 03061 . NAME ADDRESS fCITY/SWE/ZlP_ tU.S. Dollars 't£* /**.•.' -: '.-'OJbtL". m. -J*® Bison Takes the Bite Out of High Prices Epson Eradication Espon MX 80 $405 I Epson MX 80 FT $515 Epson MX 100 $695 Epson Graftrax Roms $ 74 | Epson Replacement Cart $ 11 Interface to Apple $ 84 | Monitor Munch Amdek 13" Color Monitor $346 I Amdek Color II RGB Monitor $895 NEC 1 2" Green Screen $1 66 NEC RGB Color Monitor $945 Zenith Green Screen $134 | Peripheral Portion D.C. Hayes Micromodem II $295 I D.C. 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Shipping C.O.D. based on weight. Free shipping on all orders over $500. No C.O.D. orders. Prices and availability subject to change without notice. Phone orders welcome. Mail to: Bison Products P.O. Box 9078-184 ^HP Van Nuys.CA 91409 mmSmm. FOR FAST SERVICE CALL (213)891-5702 Book Reviews The Minds I Douglas R. Hofstadter and Daniel C. Dennett, Basic Books Inc., New York, 1981. 501 pages, hardcover SI 5.50 Reviewed by Lloyd Milligan 8604 Maywood Dr. Columbia, SC 29209 This book is designed to provoke, disturb, and befud- dle its readers, to make the obvious strange and, per- haps, to make the strange obvious. (from the Preface) Most people take consider- able pleasure in being aston- ished . Witness the popular television show That's In- credible. For those who are less easily astonished, but who enjoy a special kind of challenge, Douglas R. Hofstadter and Daniel C. Dennett have "composed and arranged" The Minds I, a splendid collection of essays on mind and consciousness, "self and soul." Each essay concludes with a "Reflection" based on the editors' own thoughts and reactions. Of all the pursuits of man, science has been the most productive. In the present century, the so-called neuro- sciences (neurobiology, neurochemistry, neuropsy- chology, etc.) have con- tributed significantly to our understanding of how the human brain works. Para- doxically, however, deep issues of both historical and enduring interest have been on the whole ignored by these new sciences. The denial of mind and con- sciousness as valid topics of scientific inquiry may be traced to the influence of logical positivism, opera- tionalism, and behaviorism. The Mind's I could be said to be about those things that be- haviorism denies. A recurring theme or de- vice in many of these essays is the "thought experiment." In a thought experiment, one imagines all the procedures and conditions of an experi- ment and attempts to imagine or deduce what the outcome would be. The power of a thought experiment —and also its weakness — comes from imagining procedures which cannot be carried out in reality. The key to distin- guishing whether a thought experiment could be realiz- able is to decide if the condi- tions of the experiment are possible "in principle." In reading these essays I was sometimes reminded of Mark Twain's satire on facts and miracles: ". . . if it is a Miracle, any sort of evidence will answer, but if it is a Fact, proof is necessary." It is often difficult to know whether a suggested condition is merely technically infeasible or im- possible in principle. Fortu- nately, Hofstadter and Den- nett provide some assistance in this regard, but there is still a danger — thought experi- ments that support your point of view will seem more likely to be realizable than those that oppose it. Thus far it may not be ob- vious why The Mind's I has special interest to computer enthusiasts. That it does is partly due to a new breed of cognitive psychologists — called computer scientists — whose major research interest is artificial intelligence (AI). If your concept of AI is based on the Eliza program, then you probably need to be brought up to date. Current AI research involves topics such as simulating human ability to understand stories (Roger Schank et al.; dis- cussed by John R. Searle in "Minds, Brains, and Pro- grams," page 353). Such pro- jects shed new light on the meaning of "understanding," and at the same time expose the awesome complexity of human knowledge database design. In one sense, the ulti- mate goal of AI research is to give objective meaning to concepts that have heretofore been understood only in the subjective sense. The brain's hardware, which at the very least "sup- ports" thought, cannot be ig- nored. Several thought ex- periments in this book focus on the neural-circuit descrip- tion of brain functioning. It is easy to slip from this focus to the assumption that the brain is purely a digital machine. This assumption is unwar- ranted even at the cellular level. For example, synapses (connections between nerve cells) are not strictly analo- gous to logic gates. Thou- sands of axon terminals may impinge upon the dendrites of a single cell. The events that transpire there (at the synapse) are more analog than digital in nature. One may even speculate that it is not possible "in principle" to model these processes se- quentially in real time. While reading these essays I found myself formulating point-by-point replies. More often than not, Hofstadter or Dennett expressed my ap- proval or misgivings more clearly than I could have done. Their comments not only reflect on the essays themselves, but go on to pre- sent new variations on re- lated themes. The reader is compelled to reflect on the re- flection, and so on, until in- tellectual fatigue sets in. A common thread runs through this collection, but it is not easy to discern. Vari- ous conceptions of mind, self, and soul are set up, ex- posed, scrutinized; the idea is to inquire which, if any, of these are possible models of mind, self, or soul. The mind as a program of immense in- tricacy, involving deep "level- crossing" structures (e.g., how can a thought influence a synapse?) and Godelian loops, is one idea that emerges. The Mind's I does not ex- plain the mind's I. Perhaps it aims to describe what such an explanation would be like. In one reflection, Hofstadter is careful to distinguish emula- tion of the mind from simula- tion. Explanation is at least one step further removed. And while this book does not pretend to "explain" self or soul, the impression emerges that, with thoughtful consid- eration, these problems of the ages may be tractable, after all. At another level, The Mind's I expresses a tone of personal warmth and enthu- siasm. The authors inquire of one of Stanislaw Lem's es- says, "Is this poetry, philoso- phy, or science?" I asked myself the same question about the book as a whole and concluded that it is a combination of all three. One thing that the book is not is hocus pocus. Hofstadter and Dennett eschew pseudosci- ence. Their views are com- pletely compatible with the scientific world view. It's just that science has not yet made deep inroads into the prob- lems that make up the main focus of this book. Perhaps this deficiency will yield in part to the union of computer science, neuroscience, cogni- tive science, philosophy, and linguistics. ■ April 1982 © BYTE Publications Inc 155 SUPERBRAINS SUPERBRAIN QD 64K List $3995 only $2949 COMPUSTARS Available to Dealers NORTH STAR Minicomputer Performance Green Phosphor Options: Graphics* CP/M List $3999 Only $3199 Z-89 48K List $2895 only $2099 Z-90 64K DD 3195 ONLY $2489 ADVANTAGE Yi*W* Monitor Green Phosphor $118 TERMINALS Z-19 $718 INTERTUBE IE Super Smart $710 EPSON ^^^0^nm\\\k MX-80FT. $598 MX-80 $474 MX-100 $749 ANADEX 9501 $1290 NEC Letter Qual Friction & Tractor calf ZENITH printer Z-25 list 1595 only $1256 STARWRITER letter qual FT . . $1824 A ATARI AMERICAN SQUARE COMPUTERS is organizing a World Wide Association of Computer Dealers. Open a Store or Start Work Out of Your Home! We Charge NO FRANCHISE FEE! (Our Competitors charge a FRAN- CHISE FEE of from $15,000.00 to $45,000.00.) Be a Winner! 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William Barden Jr. 28122 Orsola Mission Vie jo, CA 92692 There's always an advantage in using existing hardware to interface external devices — there's no need to perform address decoding, to hook up to a multiline bus, or to design and implement controller functions. The cassette port is the most rudimentary input/output port in the TRS-80 Models I and III. It was originally designed to interface to an audio cassette recorder so that BASIC and machine-language programs and data could be saved and loaded. The cassette port, however, can be used in a variety of other ways. In this arti- cle, I'll describe three projects that use cassette-port output. These projects will work with a Model I system without the expan- sion interface and with any Model III. The projects are a tone generator with volume control, a telephone dialer, and an RS-232C driver. A fourth use, controlling a nuclear fast-breeder reactor, was to be included, but still About the Author William Barden Jr. has written many books on microcomputer programming and design. He is a member of the Association for Com- puting Machinery and the Institute of Electrical and Electronics Engineers. needs a little polishing up. Perhaps in a later article . . . Cassette Logic The TRS-80 Models I and III use similar logic in the cassette output, as shown in figure 1. The REMote out- put to turn on the recorder is slightly different in address decoding between the Models I and III, but in both cases it simply closes a relay. Two normal- ly open relay contacts go to pins 1 and 3 of the cassette jack, a 5-pin DIN connector. The relay output won't be used for these projects, since some of 0> CASSOUT o o TO "REMOTE" PLUG O GND REM FRONT VIEW REM U^VJ NK -CASSIN Figure 1: Model I /III cassette output is performed by a two-bit latch that generates three voltage levels. The three voltage levels can produce a square wave with a positive- going pulse, a negative-going pulse, and a zero level. A motor relay connects two nor- mally open contacts. 158 April 1982 © BYTE Publications Inc Port OFF Hexadecimal Bit 1 BitO CASSOUT Voltage (V) = = 0.4 = 0.8 = 0,4 Table 1: CASSOUT voltages. The two latch hits produce four voltage levels. The 11 configuration is redundant and is not used. DATA PULSE IF "l" OTHERWISE 00 LEVEL -1 MILLISECOND -2 MILLISECONDS BIT TIME- t 500 BITS/ SECOND) Figure 2: The recording technique for 500 hps uses a clock pulse spaced at 2-ms inter- vals. A data pulse at the midpoint between clock pulses represents a 1; the absence of a data pulse represents a 0. CASSOUT O + 4 TO +I2V ^ MINIATURE POTENTIOMETER Figure 3: In the TONOUT electronics, an LM386 audio-amplifier chip is driven by the CASSOUT signal. The output of the LM386 drives a small speaker. the earlier relays were prone to "stick- ing" (especially when used to control the AC supply for milling machines). Instead, what will be used is the output that normally goes to the AUXiliary input of the cassette recorder to write data on the tape. This is a single line connected to pin 5 (CASSOUT) of the DIN connector. This line is driven by two bits at I/O address OFF hexadecimal in both the Models I and III. Three voltage levels can be output to the CASSOUT line, depending upon the configuration of the two least significant bits of port OFF hexa- decimal (see table 1). A bit configura- tion of 01 binary produces about volts (V), 00 produces about 0.4 V, and 10 produces about 0.8 V. Bit con- figuration 11 is redundant as it generates 0.4 V again. The three voltage levels are used to write data onto the cassette in the 500-bits-per-second (bps) mode, as shown in figure 2. A single square- wave cycle is first generated to pro- duce a clock pulse. Then, either another cycle is output, representing a 1 data bit, or no cycle is output, representing a data bit. The Model III also has 1500-bps capability. In this mode, continuous frequency -shift keying is used, with 1320-hertz (Hz) and 2680-Hz tones representing the data. Only the 0- and 0.8-V levels are used for this scheme. In both cases, the major part of the logic is in the ROM (read-only memory) firmware. The electronics really just consist of the two output latches and a few resistors. In the following projects, I'll use the two bits of port OFF hexadecimal to generate square waves for musical tones, telephone dialing, and RS- 232C output. The greater part of the design effort, as in the TRS-80 cassette functions, is in the software. The hardware will consist of three simple circuits with a minimum of parts. (A note about connectors: For con- necting all three projects to your TRS-80 cassette port, use a standard, thin-walled, 5-pin DIN plug, such as Radio Shack's catalog item 274-003.) A Musical Tone Generator Our first project produces six oc- taves of notes representing the first six octaves on the piano keyboard. The notes are square waves, rich in odd-order harmonics. Two volume levels can be output, one using the 0- and 0.4-V levels, and a second using the 0- and 0.8-V levels. The circuit shown in figure 3 uses the CASSOUT output as an input to an LM386 audio amplifier. The LM386 requires only a capacitor and 8-ohm (12) speaker to implement a complete audio amplifier. A minia- ture 10-kO potentiometer is used at the input for volume control. The power supply for the LM386 can be any convenient voltage from +4 to + 12 V. A 6-V battery works fine for the power supply, or you can obtain a low-priced power-supply kit from Radio Shack. TONOUT (listing 1) is an assem- April 1982 © BYTE Publications Inc 159 Circle 263 on inquiry card. Your 8 por **& Sector- Fe ed - tn ;modul«- c mem° r ^ ddr essline- BUffere te power suPP'V- Sepaf mandwit^ ./0-^ f a BAS.C. |/O$1 09 8-Port bus- 2 cWf# output- AD ClOCk reconnects |,ObUS h |e0.1° r1SeC BeeP er - n in i all o' derS - dod"! ,w ' , c " h arge on a' hand TOLL*** write us at- BoxJ140 2000 Center St., Berkeley, mi«o CA94704 dttvalopmentz Listing 1: TONOUT is a Z80 subroutine to output tones through the cassette port. The code is to be embedded in the BASIC program of listing 3. 9000 9000 9003 9004 9006 9009 900 C 900F 9010 901 1 9013 90 I 4 9017 901 A 90 IB 90 IE 90 IF 9021 9023 9024 9025 902/ 902a 902 A 902 C 90:20 902E 9030 9031 9033 903'::? 9036 9037 9039 903 C 90 3D 903F 904 1 9042 9043 9044 904'::. 904/: 9047 9049 9 04 A 904 C 904 E 904F 905 905 1 905 2 905 3 9054 9056 9058 0000 CD7F0A E5 DDE 1 DD4E04 DD6603 DD6E02 7C B7 2022 45 DD660 1 DD6E00 2B 1 IFEFE IT 07 D3FE 78 3D 20ED 79 3E02 D3EF 7 g 3D 20FD 19 38EB 1B23 E5 Dl CB83 DD4600 79 EE02 D3FF 3E02 D3EF 2B 7C B5 20EA 10E4 C9 00100 00110 00120 00130 00140 00150 0015 1 00160 00170 00180 00190 00200 00210 00220 00230 00240 00250 00260 00270 00280 00290 00/00 00310 00320 00330 00340 00350 00360 00370 003S0 00390 00400 00410 00420 00430 00440 00450 00460 00470 00480 00490 00500 005 1 00520 00530 '00540 00550 00560 00570 0058W 00590 00600 00610 00620 00630 00640 00650 00660 00670 00680 00690 00700 00710 00720 00730 00740' 00750 00760 00770 ORG 9000H ; # ft *■ ft # ft # * « ft ft # ft # # ft ft f * ft # * * * ■* ;■*■ TONE OUTPUT. OUTPUTS TONE THROUGH ;*• ENTRY": HL = > PARAMETER BLOCK I* PARAM+0=DURATION CNT IN 2 BYTES f* +2=FREQ CNT*( 18.04 MICROSECE I ft 1 5 . 79 M 1 CROSECS NOD I II), i ft # ft *■ ft ft ft * ■* * ft- ft *• * *■ * * ft ft * ft * ft- * ft ft ft * ft- CASSETTE PORT. * NOD I 2 BY TEE ;* +4^LEVEL: 2-LOW. 3*WIGtti ONE BYTE * J* EXIT: AFTER TONE HAS SOUNDED ft ; ft ft ft ft » » ft * * ft ft *• # ft ft ft- * ft ft ft * ft ft ft * ft ft *■ ft * ft * ft * ft ft ft ft ft- ft ft ft ft * ft ft » * ft * -ft ft * * ft ft TONOUT CALL PUSH POP ED ED ED L..D OR JR J HIGH FREQUENC ED L.D LD DEC L.D HI 010 LD XOR OUT LD HI 020 DEC JR LD LD OUT' LD HI 030 DEC J R ADD J R J R 5 LOW FREQUENCY LOWE RE PUSH POP RES LD LOW010 LD XOR our LD LD LOW020 DEC DEC LD OR JR LD LD OUT LD LD DEC DEC LD OR JR DJNZ RET END 0A7FH HE LOW030 LOW090 IX Ci ( IX + 4) Hi ( IX-F3) Li t IX +2) A , H A NZ, LOWE RE V HERE B i L H» < I X +■ 1 ) L, ( IX+0) HI- DE , 1 A i C ( 0EFH ) i A A , B A NZa»s.„n „.„•,., avai/.M, .'"""""^""Iviompk.,,, „ " Computer. 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The same frequency count is used for both the on and off delays; hence, the period of the tone is twice the delay time. A = USR IB) B POINTS TO-^ PARAMETER BLOCK + 0* + 1 DURATION COUNT 1-65,535 - >Z80 FORMAT LSB, MSB + 2 + 3 FREQ COUNT 1-65,535 " >Z80 FORMAT LSB, MSB + 4 LEVEL: 2 OR 3 Figure 5: Three parameters are used to interface to TONOUT from BASIC. A duration count is held in two bytes, a frequency count in two bytes, and a level in one byte. The counts are in standard ZSO address format: least significant byte followed by most significant byte. the Model I (15.79 for the Model III) on the "on" and "off" portions of the square wave, as shown in figure 4. Therefore, the frequencies of the square waves produced are 1/(36. 08E-6) and 1/(31. 58E-6), respectively. The duration count of 1 to 65,535 determines the length of time the tone is played. In fact, the duration count is the number of cycles of the tone. Thus, the length of time the tone plays is dependent upon the tone's frequency. To play a "quarter note," the duration count would be 25 for a 100-Hz tone, 50 for 200-Hz, and so forth. The duration count is 1 /fre- quency times the fraction of a second the tone is to be played. The third parameter is volume level. A value of 2 is low and 3 is high. The level parameter is in one byte. The main problem in TONOUT is how to get the "tightest" possible loop to toggle port hexadecimal OFF bits on and off and still allow for low- frequency notes with a longer dura- tion. The approach used here is to split TONOUT into two segments of code, one for high-frequency notes, and one for low-frequency notes. TONOUT is entered from BASIC by a DEFUSR call. The CALL 0A7FH gets the argument from BASIC and puts it into the HL register pair. The argument in this case is a pointer to a parameter block of the three arguments in 7 bytes (see figure 5). This pointer is transferred to the IX register. The level parameter is put into the C register and the frequency count is put into HL. Next, the frequency count is tested for magnitude. If the H register is nonzero, the frequency count is greater than 255, and a low- frequency note is played. If the frequency count is less than 256, the high-frequency segment is executed. The single byte of the fre- quency count is transferred to the B register. Also, the two bytes of the duration count are transferred to HL and decremented by one for the JR C loop. (C will decrement below before the loop is terminated.) The DE register pair is loaded with — 1 for a "tight" timing loop. The output portion of the loop con- sists of two almost identical seg- ments. Lines 350 through 400 are the "on" portion that turns on the "top" of the square wave. Lines 410 through 460 turn off the output. Both portions decrement the frequency count in a timing loop that determines the fre- quency. The voltage level for the "on" portion is determined by performing an XOR of binary 10 and the level parameter to produce either a 00 (low) or 01 (high). After one complete cycle, the dura- tion count in HL is decremented by an ADD HL,DE. If the result is not negative, another cycle is generated. The code from line 510 through the end is a similar routine for low- frequency notes. In this case, the fre- quency count is held in HL and decremented twice. The frequency count is first made even by a RES instruction for a test of decrementing down to zero. The duration count is assumed to be 254 or less and is held in B for a DJNZ instruction. Using TONOUT with BASIC TONOUT can be used to generate tones other than musical notes. The precise frequencies generated are: l/((42.49 + 18.04 X count) X 10" 6 ) for high-frequency tones and: 1/((41.15 + 18.04 X count) X 10" 6 ) for low-frequency tones. These for- mulas are for the Model I. Use (37 + 15.79 X count) and (36 + 15.79 X count) for the Model III. The 18.04 (or 15.79) represents the on/off loop times; the other constants represent the "overhead" for the fre- quency and duration timing. BASIC can easily be used to build up a table of values for matching fre- quency counts to musical notes. 162 April 1982 © BYTE Publications Inc ^J 256KB IBM PERSONAL ^F COMPUTER MEMORY! SINGLE BOARD 256KB IBM PERSONAL COMPUTER MEMORY Designed Specifically for IBM's PERSONAL COMPUTER is Chrislin Industries newest CI-PCM Memory Module. FEATURES INCLUDE: • On-board parity generator checker • Addressable as a contiguous block in 64K byte increments through 1 megabyte • Access time of 225 NSEC • Requires only one I/O expansion slot for 256K bytes memory • Power requirements are +5V at 1.0A max. • Cycle time of 400 NSEC SEE YOUR LOCAL COMPUTER STORE FOR DETAILS OR CALL US. DON'T ASK WHY WE CHARGE SO LITTLE, ASK WHY THEY CHARGE SO MUCH. tf 1 Chrislin Industries, Inc. ^B* J 31352 Via Colinas • Westlake Village, CA 91362 • 213-991-2254 ^^-^ TWX 910-494-1253 (CHRISLIN WKVG) Circle 84 on inquiry card. BYTE April 1982 163 uircie jdo on inquiry card. c \ NEW Listing 2: A BASIC program to generate frequency-delay values that, when input to the TONOUT routine, will reproduce tones in standard pitch. Results are shown in table 2. for the 20 T PROGRAM TO FIND BEST FIT FOR 8 OCTAVES 40 DIM NT*< 11 ) ▲ ^¥1/1 60 A$-^"A AttB C C#D D#E F F#G G#" mi «rf # 80 FOR J=0 TO 11 i^r m* 1 - 100 NT* ( J ) =M I D* ( A* . J #2+ 1,2) *^ JL^%r 120 NEXT J J 40 FOR 1=0 TO 7 PC-8000 Series 160 RESTORE 1B0 L PR I NT "OCTAVE " ; 1 + 1 * AND MORE * j 200 FOR J = TO 1 1 220 LPRINT NT*< J) \ "«■ ! 240 N* ( 2 7 . 5*2f I > *2 1 < ( J ) / 1 2 ) : LPR I N IN » 260 CT« U'J /N J -36 . 5E-6 ) / 1 5 . 79E--6 2S0 L. PR INT "F CNT-" ;C'f 300 NEXT J from Renaissance Technology r" The Wedge > • Fully emulates all features of the NEC 320 NEXT I PC-8012A module • NEC PC-8001A Sl/O (terminal mode) channel is brought out to a DB 25 con- nector • Additional ports for 40 bits of digital I/O and analog input including 2 Atari-type joystick ports; built-in 3 voice synthe- OCTAVE 1 sizer with amplifier A = 27.5 FCNT = 2300.64 • 32K RAM card included; also capable of A# = 29.1352 F CNT = 2171.39 handling another 32K RAM - 96K of B =30.8677 FONT =2049.39 RAM C = 32.7032 FCNT= 1934.23 • 16 levels of interrupt capability C# = 34.6478 FCNT = 1825.54 • NEC PC-8012A bus structure is imple- | mented. • Attaches easily to the bottom of the NEC PC-8001A. D = 36.7081 FCNT= 1722.95 D# = 38.8909 F CNT= 1626.12 E = 41.2035 FCNT= 1534.73 Ren Tec Wedge $595 00 F = 43.6535 FCNT= 1448.46 RS-232-C Interface Card F# = 46.2493 FCNT= 1367.03 for NECPC-8012Aor G = 48.9994 F CNT = 1290.18 Ren Tec Wedge 179.00 G# = 51.9131 FCNT = 1217.64 32K Memory Board for NECPC-8012Aor Ren Tec Wedge 199.00 Table 2: Calculating counts for musical notes. A short BASIC program can match TONOUT frequency counts with standard pitch values. Here are the results. RGB Color Converter for NEC PC-8001A l (40 column only) 99.00 j and 'NEC Dot Matrix Printer 795. 0Q i • 100 CPS • Bidirectional printing • Friction and tractor feed ♦ Parallel interface • Single-ribbon cartridge MODEL I NEC Monitors • 12" Green Screen 285.00 OCTAVE • 12" RGB Color 1095.00 l • 12" Composite Video 430.00 j 1 2013,1900,1793,1692,1597,1508,1423,1343,1268,1196,1129,1065 2 1005,949,896,845,798,753,710,670,632,597,563,532 3 502,473,447,421 ,398,375,345,334,31 5,297,280,265 4 250,235,222,210,198,186,176,166,154,147,139,131 * more * •"ATARI 10-Key Accounting Pad . 124.95 "X Olympia Letter-Quality Printer 5 124,1 17,1 10,104,98,92,87,82,77,73,68,64 • Ren Tec ES Series Interface 6 61 ,57,54,51 ,48,45,42,40,37,35,33,31 converts typewriter to letter- quality printer • for Apple, Atari, Commodore. NEC, Osborne 1 , TRS 80 and others Ren Tec Interface for MODEL III V ES 100/101 295.00 J OCTAVE 1 2300,2171,2049,1934,1826,1723,1626,1535,1448,1367,1290,1218 {^ ^ 2 1149,1085,1024,966,912,860,812,766,723,682,644,608 RENAISSANCE 3 573,541,511,482,455,429,405,382,360,340,321,303 4 286,269,254,240,226,213,201,190,179,169,159,150 TECHNOLOGY 5 142,134,126,119,112,106,99,94,88,83,78,74 6 70,66,62,58,55,52,49,46,43,40,38,36 ^^CORPORATION JPfc \ Table 3: Frequency counts for standard pitch. Six octaves of note values are represented by the values in the table. Models I and HI use slightly different values W Si >^L-r^ 3347 VINCENT ROAD W ^Y^lflhf PLEASANT HILL. CA 94523 because of the difference in clock rates. a filtfV (415)930-7707 164 April 1982 © BYTE Publications Inc H you don't know a baud from a flop; YOU NEED TO KNOW THE QDP-lOO MICROCOMPUTER Most people who need computers don't have the time, or desire, to become full-time computer "wizards," With the budget-priced QDP-lOO you get all the time-saving pre- cision information you want from a computer, now and in the future, without all the unnecessary com- plexity associated with less consider- ate computers. QDP-lOO IS A FULL-SCALE 8-bit computer, readily upgradeable to 16 bits as your business or professional information- processing needs grow It uses the IEEE S-lOO bus, compatible with CP/M and MP/M disk operating systems, QDP-lOO HANDLES BOTH floppy disks and hard disks to give you total software versatility. QDP-lOO CONNECTS INSTANTLY to any standard terminal and printer Both serial and parallel ports are available. Features most micro- computers can't match, It does more, does it easier, and costs a lot less. it? : L ^ QDP-lOO HAS SINGLE BOARD SIMPLICITY Eliminates the hassle of complex multi-chip, mul" board computers. QDP-lOO IS EASY to learn and t operate. Most owners use their QDP-lOO with professional skill and results in short order. Our instruction manual doesn't need an interpreter. If you'd rather be a wizard with computer results, than with computers, choose the QDP-lOO. Call or write for literature and full details. QDP NEEDS A FEW MORE GOOD DEALERS. Attractive, profitable, protected dealerships are still available in several high-potential computer market areas. Quasar Data Products 10330 Brecksville Road Cleveland, Ohio 44141 216/526-0838 Telex: 241596 CP/M and MP/M are registered trademarks of Digital Research Listing 3: The BASIC program to demonstrate tone generation with the Model I/III cassette port. The DATA statements contain the machine-language codes of the TONOUT subroutine. 40 REM BAMPI E T0N0U1 si> DATA ,'i/v, , L27i L( 64 Mb j > i j 100 DI I ■ : ' ; ■ ; &H >&&& I i I NPU i Di F s L ! '8 POKE &HA00J i iN'i - D 1 ; : . . i, »003? I N I ( I 9- > 9- ) 9- -© -€ -© -€> i ( c ( ( « < < < ! ( 1 ( < ( < < < ) > ) ) ) > > > > > > > ) > > > -e -© -© -© -© -e -e -© -e -© -© -© -© -© -© ) 9- ) 9- ) 9- ) 9- > 9- -© -© -© -© -© -o ) 9- -© © © Figure 6: Radio Shack's Experimenter Socket project board uses a matrix of holes into which component leads can be plugged. The holes are organized into 46 sets of five plus two buses. Listing 2 shows a Model III BASIC program for converting to standard pitch (A = 440 Hz). (The Model I version is identical except for the con- stants.) This scheme has 12 notes per octave: A, A# (A sharp), B, C, C#, D, D#, E, F, F#, G, and G#, each calculated by raising 2 to successive one-twelfth powers. The notes of each octave double in frequency over the preceding octave. The first portion of output from the program of listing 2 is shown in table 2. Table 3 shows suggested integer counts for the notes for the Models I and III. Listing 3 shows the TONOUT pro- gram incorporated into a BASIC pro- gram as DATA values. The DATA values are the machine-language bytes of TONOUT. TONOUT is relocatable and can be moved anywhere in RAM (random-access read/ write memory). The program in listing 3 moves the bytes to 9000 hexadecimal by a series of POKEs. It then INPUTs a duration count, fre- quency count, and level value for ex- perimentation. Constructing the Electronics All three projects in this article use a similar construction method. Radio Shack carries an Experimenter Socket project board, which is a matrix of 23 rows, each with two halves, as shown in figure 6. Each of the 46 row segments is connected electrically. Two buses run down the board on the extreme right and left. Components can be plugged into the board with a minimum of fuss. The interconnections for the TONOUT electronics are shown in figure 7, along with the power sup- ply, speaker, and cassette plug con- nections. Make the connections to the 5-pin DIN plug, as shown in figure 8. To get precise frequencies for TONOUT, it's a good idea to disable the real-time clock interrupts in the Models I and III. If the real-time clock is running (and it may be, even without a display), the timing on tones may be off by 4 percent, and there may be some modulation on the tone. Add a disable interrupt (DI) in- struction (243 decimal) at the begin- ning of TONOUT and an enable in- 166 April 1982 © BYTE Publications Inc Circle 254 on inquiry card. INTRODUCING MetaCard The future for your Apple II. MetaCard will turn your Apple II personal computer into tomorrow's high performance machine. It triples the memory of your Apple, and at the same time, greatly increases the processing speed with an Intel 8088 16-bit microprocessor. The future for your Apple is built into MetaCard. Enough Memory to get the Job Done MetaCard has up to 128 K bytes of onboard memory with parity. Adding K- BYTES Apple 6502 Intel 8088 Add-on Memory MetaCard to your Apple's existing 64K bytes of memory gives you three times the capacity, and opens the * door to applications never before possible on your system. Faster Processing Speeds Speed is just as important as memory. MetaCard is designed to handle all computing tasks at greatly increased speeds. The Intel 8088 operates at the full 5MI1Z, running most applications at least 4 times faster than the Apple's iMhz 6502. And MetaCard gives you multiprocessing capabilities, allowing both the 8088 and 6502 to run simul- taneously at full speed. Increased processing speeds, interprocessor interrupts and a real-time clock enable your Apple to perform like the machine you want. Compatibility and Reliability Compatibility has been designed into MetaCard. Metamorphic's processor card runs CP/M-86, which is included with the card at no extra cost. And Metamorphic offers UCSD Pascal 4.0 and the operating system for the IBM Personal Computer as options. Full parity checking, power-up diagnostics and a 48 hour burn-in will insure the reliable performance of your MetaCard. Find Out More Not everyone needs greater memory and speed. If you're one of those who does, MetaCard is for you. At an introductory price of $980 for the 64K configuration, it's not the least expensive addition you can make to your system, but high performance products never are. Call us today and find out what Metamorphic Systems has in mind for your Apple's future. Dealer inquiries welcome. Metamorphic Systems, Inc., P.O. Box 1541, Boulder, Colorado 80306, (303) 499-6502. Intel 8088 is a product of Intel Corporation. Apple II is a registered trademark of Apple Computer Inc. CP/M-86 is a registered trademark of Digital Research Corp. IBM Personal Computer is a registered trademark of IBM. UCSD, Pascal is a registered trade mark of the University of California. METAMORPHIC SYSTEMS, INC. l %. ANOTHER CRATE IDEA FROM ALTOS! The complete multi-purpose, multi-terminal desktop business computer system with a built-in tutor. Now you can get everything you need to computerize your business. An ALTOS ■ Series 5 computer (including 5 MByte Winchester hard disk that stores over 1,800 pages). Three of our new smart terminals and a quality printer. Plus the ALTOS COMPUTER TUTOR, the self- teaching business software package that provides simple, self-paced, step-by-step instructions and training. All for less than $4 /day per user. Virtually overnight, your opera- tors will become faster and more accurate since an Altos system is like having three computers in one. For example, while your book- keeper prepares payroll, other users can check inventory, compute cost estimates, or produce ?rror-free reports. All at the same time. An Altos system lets you communicate with ! other computers, main- frames and networks. Need more? For less &; than another $l/day, . each user can have Wordstar™ for word processing and Microplan™ for busi- ness analysis. Plus you can choose from hundreds of other popular CP/M®, MP/M II™ and OASIS applications programs. There's also nationwide on-site service available from your dealer. Join the thousands of busi- nesses, professionals and institu- tions who already rely on Altos. Call our toll free number or write Altos Computer Systems, 2360 Bering Drive, San Jose, CA 95131 today. We'll put you in touch with your local Altos sales and service dealer who'll crate an Altos busi- ness computer system exclusively for you. 'Complete 3 user system for $4/day per user. Price approxi- mate and may vary in your area. Daily lease based on 513,800 principal, 20% annual interest, five-year term. Packaged system includes Altos Series 5-5D computer with 5 MByte Winchester hard disk, draft quality printer, three Altos smart terminals, and the ALTOS COMPUTER TUTOR software package. Price does not include tax. installation, training and maintenance. Packed with fresh ideas for business COMPUTER SYSTEMS 800-538-7872 (In Calif. 800-662-6265) ALTOS is a registered trademark of Altos Computer Systems. WordStar is a trademark of MicroPro Inter- national Corp. Microplan is a trademark of Chang Laboratories, Inc. CP/M is a registered trademark and MP/M II is a trademark of Digital Research. Inc. OASIS is a product of Phase One. Inc. • 1982 Aitos Computer Systems Circle 23 on inquiry card. circle 289 on inquiry card. Mil stocks 'em all for faster delivery. Ask about our " QEO "discounts. VISA and MasterCard orders accepted. 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NewYork: 516/482-3500, 212/895-7177, SIS/449-5959 Outside N. Y.S.: 800/645-8016 New Jersey: 201/227-5552 I Ohio: 216/464-6688 170 April 1982 © BYTE Publications Inc TO CASSETTE PLUG TO SPEAKER RADIO SHACK 276-175 EXPERIMENTER SOCKET WIRING DIAGRAM (SEE FIGURES) i i Figure 7: The TONOUT circuit is mounted on a project board. It uses three com- ponents. The 10-kQ potentiometer can be adjusted for a comfortable volume. terrupt (EI) instruction (251 decimal) right before the 201 decimal for the RET; modify the POKE loop accord- ingly. The DI and EI were omitted from TONOUT to give the user some flexibility in using the project in dif- ferent configurations. A Telephone Dialer Our second cassette-output project is a pulse-type telephone dialer (TELDIL). Most telephone lines, even those using tone dialing, will accept dialing by a series of break/make pulses, spaced at defined inter- vals — similar to those created by a rotary-dial telephone. See figure 9 for an illustration of pulse dialing. The circuit for TELDIL is shown in figure 10. Put simply, the circuit opens and closes a relay to generate USE SHIELDED WIRE (GROUND IS SHIELD) PREFERABLY GROUND LEAD CASSOUT LEAD Figure 8: Two wires are connected to the 5-pin DIN plug for the cassette port. Shielded wire is preferable, but any wire will suffice. pulses, which are then transmitted to the telephone line through a special Data Access Arrangement (DAA) re- quired by and available from the telephone company. The TELDIL Circle 310 on Inquiry card, «^^ The Grappler 1 is intelligent Apple ' able. Simple com keyboard or user program, are alt you need to dump screen graph- ics to your printer. The Grappier's exclusive EPROM chip makes high resolution graphics easy. There are Grappk sions to accommodate Anadex, Epson Series * IDS Paper Tigers, Centronics 739, NEC 8023, C. Itoh Pro-writer, Okidata 82A,* Malibu 200, and future graphic printers. •Requires Graphics Upgrade. ffllil TV-- features en Dump lies Graphics ize Picture tion raphics _rt Recorder Mode ock Graphics Ml Control ► Skip-over-Perf * Left and Right Margins * Variable Line Length * text Screen Dump. The Grappler™ works with Pascal, and CPM. ° ! sfcOronge micro inc. 3150 E. La Raima, Suite G, Anaheim, CA 92806 (800) 854 8275 TOLL FREE (714) 630 3322 CA; AK: HI. (h ■ii MAKE BREAK 4 PULSES REPRESENT DIGIT "4" Figure 9: Standard rotary dialing outputs a series of evenly spaced pulses to represent the digits through 9. CASSOUT RADIO SHACK MINI RELAY (275-004) FROM TELEPHONE DATA ACCESS ARRANGEMENT Figure 10: The telephone-dialing circuit uses an operational amplifier to trigger a small relay. The relay opens and closes the telephone line through the Data Access Arrange- ment to simulate a rotary-dial pulse. "INTERDIGIT" DELAY OF 830 ms- li MAKE BREAK t 61.5 ms 100 ms/ PULSE (10 PULSES/sec) Figure 11: TELDIL breaks the circuit for 38.5 ms. Pulses are spaced at 100-ms intervals, representing 10 pulses per second. An interdigit delay of 830 ms separates the pulse trains for each digit. B^VARPTR (A$) B POINTS TO — — ■ J\ LENGTH USRO (B) / POINTS I LOCATION OF A$ ) Z80 ADDRESS FORMAT | LSB.MSB T0 V ^ s. 49 10 DIGIT* 1 50 10 DIGIT = 2 -" *9 10 DIGIT= 1 54 10 DIGIT = 6 TERMINATOR IS NOT ASCII Figure 12: BASIC passes a pointer to TELDIL. The pointer references a list of ASCII digits representing decimal values; the list is terminated by any non-ASCII value, e.g., binary 0. relay is driven by an LM3900 opera- tional amplifier (op amp), which in turn is driven by the TRS-80's CASSOUT line. Whenever the CASSOUT output level is greater than or less than V, enough current flows through the 220-0 resistor to turn on the LM3900, bringing the output on pin 5 to V. This closes the relay and breaks the connection to the DAA. The diode (Radio Shack's lN4000-series diode, catalog number 276-1102) across the relay coil is necessary to prevent high-voltage "spikes" from the induc- tive load of the relay coil from damaging the LM3900. The software for TELDIL is also a relocatable assembly-language pro- gram that interfaces to BASIC (see listing 4). Although the version shown here uses a delay loop for the Model I, there is enough "leeway" in the constants to use the same code for the Model III as well. The "make/break" rate for digits is limited to 10 pulses per second for most telephone systems. The circuit is broken for about 38.5 milliseconds (ms) for each pulse, and then made for 61.5 ms, as shown in figure 11. In- terdigit delay is about 830 ms. These delays can be adjusted for faster dial- ing on an experimental basis. BASIC passes a pointer to TELDIL in the USR call. The pointer references a string of ASCII decimal digits, such as "17145551212." Any number of digits can be used. The last byte of the string is a non-ASCII digit, such as binary (see figure 12). TELDIL uses two loops. The outer loop from lines 250 through 480 picks up the ASCII digit from the string, tests it for valid ASCII decimal codes of through 9, converts the digit into a stream of 1 through 10 pulses on the line, and increments the string pointer. It also delays 830 ms for the interdigit delay. The inner loop at lines 330 through 430 pulses the line for each digit. The line is broken by outputting binary 01 to port OFF hexadecimal and then delaying 38.5 ms. The line is then reconnected for 61.5 ms. The number of pulses is held in the B register, and the DJNZ repeats the loop for the number of pulses required. 172 April 1982 © BYTE Publications Inc BEAUTIFUL PROGRAMMING WITH THE BRIDGE 3C" COMPUTER. Develop two programs for the time of one. Sounds too good to be true? With the new BRIDGE 3C Compiler System you can easily do it! This new fully integrated BRIDGE system is designed for the professional who needs a powerful computer for software development. Our 3C System includes Pascal, C, and ... a completely structured FORTRAN compiler package. What's more, you utilize the full 256 K of memory with MEMDISK m and overlay linker. Check the capabilities it offers, and plan to make your work more ant and productive with the BRIDGE 3C :: UNIQUE SOFTWARE 1 2.2 enhanced by Cache BIOS ™ performing disk buffering, and MEMDISK,™ virtual disk, speeding operations 4 to 10 times. • Operating utilities and diagnostics (all source code included). • Interrupt driven console with type-ahead buffering. • BMATE ™ screen oriented text editor/word processor. • R80 ™ RATFOR preprocessor, FORTRAN compiler, true overlay linker and symbolic debugger for fast structured application programming. • Enhanced FORTRAN library including. . . 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BRIDGE offers monthly seminars (BRIDGE User Group) plus 90 day hardware warranty and software support, with optional 2-year extension. If you need a truly professional computer, start thinking about the BRIDGE 3C Compiler System. For complete information and prices, call us at (617) 244-3203 or write today. 3C, MEMDISK, BMATE, R80, STRLIB and EASYPAK are trademarks of BRIDGE Computer Company, Division of Sea Data Corporation Cache BIOS, SWAT and Pascal-Z are trademarks of Ithaca InterSystems, Inc. i Computer Company ik. JM DMSION OF SEA DAIA CORPORATION ONE BRIDGE STREET NEWTON, MASS. 02158 U.S.A. Circle 59 on inquiry card. Listing 4: TELDIL is a Z80 subroutine to simulate a rotary telephone dialer. 9*380 00100 ORG 9000H 00110 ;*************####*#*##»#*##*#*######*#* ## * # # ### * # # # ^ ### 00120 5* TELEPHONE DIALER. DIALS ANY NUMBER OF DIGITS FOR 00130 S* ROTARY-TYPE PHONE THROUGH CASSETTE PORT. 00 1 40 i* ENTRY: HL*> STRING OF ASCII DECIMAL DIGITS, TERM- 00150 ; * INATED BY NON- -ASCII 00160 !* EXIT: AFTER NUMBER 1 HAS BEEN DIALED 00170 ;♦**♦*♦***♦*♦##*♦*#♦#*#♦**♦*♦**#*##♦*♦♦♦***##*########** 00180 ; 0604 00190 PULSE EQU 1540 138.3 MS PULSE 099C 00200 WAIT1 EQU 2460 ;1B PULSES PER SECOND 7814 00210 WAIT2 EQU 30740 ;B30 MS INTERDIGIT 9000 CD7F0A 00220 TELDIL CALL 0A7FH 5GET ARGUMENT IN HL 9003 E5 00230 PUSH HL ;MOVE TO IX 9004 DDE1 00240 POP IX ?IX POINTS TO STRING 9006 DD7E00 00250 TEL005 LD A? (IX) ;GET NEXT DIGIT 9009 D630 00260 SUB 30H 1 CONVERT TO BINARY 900B 2002 00270 JR NZ,TEL010 J 60 IF NOT 900D 3E0A 00280 LD At 10 50-USE 10 PULSES 900F 3828 00290 TEL010 JR Ci TEL090 !RTN IF LT 30H 9011 FE0B 00300 CP 11 ;TEST FOR GT 10 9013 3024 00310 JR NCTEL090 ; RETURN IF GT 10 9015 47 00320 LD BiA ;# OF PULSES IN B 9016 3E01 00330 TEL 020 LD A» 1 ;0N CODE 9018 D3FF 00340 OUT (0FFH)iA 5TURN ON RELAY 901A 210406 00350 LD HL, PULSE ; DELAY CONSTANT 90 ID 0E00 00360 LD C,0 ; RETURN FLAG 901F 1819 00370 JR DELAY ! DELAY 9021 3E02 00380 TEL030 LD A, 2 ?OFF CODE 9023 D3FF 00390 OUT (0FFH) ,A ;TURN OFF RELAY 9025 219C09 00400 LD HL,WAITI 5 BETWEEN PULSE DELAY 9028 0E01 004 1 LD Ct 1 5 RETURN FLAG 902A 180E 00420 JR DELAY ; DELAY 902 C 10E8 00430 TEL040 DJNZ TEL 020 ILOOP IF MORE PULSES 902E 211478 00440 LD HLiWAIT2 ? BETWEEN DIGITS DELAY 9031 0E02 00450 LD Ci2 ; RETURN FLAG 9033 1805 00460 JR DELAY ; DELAY 9035 DD23 00470 TEL050 INC IX ;BUMP STRING POINTER 9037 1SCD 00480 JR TEL 005 SLOOP FOR NEXT DIGIT 9039 C9 00490 TEL 090 RET J RETURN TO BASIC 00500 ! DELAYS 24.81*CNT IN MICROSECS + OVERHEAD 903A 2B 00510 DELAY DEC HL ; DECREMENT DELAY COUNT 903B ED5F 00520 LD A*R STIME WASTER 903D ED5F 00530 LD A*R ;TIME WASTER 903F 7C 00540 LD A,H ;TEST HL 9040 B5 00550 OR L 9041 20F7 00560 JR NZ» DELAY SLOOP IF NOT DONE 9043 CB49 00570 BIT 1 i C ■TEST FOR RTN PNT 2 9045 20EE 00580 JR NZ*TEL050 ISO IF RTN PNT 2 9047 CB41 00590 BIT 0,C 5TEST FOR RTN PNT 1 9049 20E1 00600 JR NZ,TEL040 ?G0 IF RTN PNT 1 904B 18D4 00610 JR TEL030 ;RTN PNT 0000 00620 END DELAY is a simple time-delay routine that delays 24.81 fis times the HL count. To keep the code relocat- able, DELAY is not entered via an or- dinary CALL, which would have a nonrelocatable address, but is called with a code for the three return points. Listing 5 shows the machine- language code of TELDIL incor- porated within a BASIC program. In this case, it is moved to 9000 hexa- decimal, but it could be relocated to any convenient area in memory. The ASCII string is INPUT and a CHR$(0) is concatenated to the string for the terminating character. VARPTR is used to find the string location. Make certain that VARPTR is used immediately before the USR call because string variables move. The "C -65536" adjusts for addresses in the upper 32K bytes of RAM; for a 32K- or 48K-byte system, this would normally be the area in which string variables would be located. String variables within a BASIC program line, however, have addresses that represent the location of the program line, and the argument in the USR call must be adjusted accordingly. Constructing the TELDIL Circuit TELDIL uses the project board discussed earlier (see TONOUT). The components are connected as shown in figure 13. Power-supply voltage should be more than 6 V; the relay shown will not work well with a 5-V supply. The cassette plug is connected as shown in figure 8. Listing 5: A BASIC program to demonstrate telephone dialing via the TRS-80 cassette port. The DATA statements contain the machine-language codes of the TELDIL subroutine. 40 REM SAMPLE TELDIL DRIVER 60 A=-0:B^0:C-0:A$^"" 80 DATA 205 , 127, 10, 229, 100 120 140 1 60 180 200 220 240 260 280 300 320 340 360 380 400 420 21, 225, 221 DATA 48. 32, 2, 62, 10, 56 i 40* 254, DATA 36, 71, 62 i 1, 211, 255, 33, 4, DATA 0, 24, 25, 62, 2, 211, 255, 33* DATA 14, 1, 24, 14, 16, 232, 33, 20, DATA 2i 24, 5, 221, 35, 24, 205, 201 DATA 95, 237, 95, 124, 181, 32, 247, DATA 238, 203, 65, 32, 225, 24,212 126, 0, 11, 48 6 < 1 4 95, 237, 95, 238, 203, 65 CLEAR 500 D£FUSR(8=&H900B FOR 1-36864-65536 READ A: POKE I, A NEXT I INPUT A*: A*=A*+CHR*<0> B^VARPTR(A$) OPEEK ( B+ 1 ) + ( PEEK ( B+2 ) ) * A=;U5R0. *r 4& j&kfiy *^ V** .« v 5» vV ^ :|=WAMi.!:I.I^:!.W=icW IN THE WORLD- WANGWRITER Compumart is proud to announce the addition of Wangwriter to our product line. The finest word processor in the world. The Wangwriter is actually four products in one— a typewriter, a word processor, a CP/M personal computer, and an intelligent terminal. You'll find these outstanding features on the Wangwriter: • Dual disk • Up to 128K memory • CP/M • Advanced word processing — Math, merge, sort and auto pagination • 75 pages of text on each 5V4 M disk • Supercalc • Communications option — Connects to RS232 Interface — Or Wangnet. It's no wonder that Wang, with 65% of the shared logic word processing market is the number one company in the field. When you think of word processing, think of the Wangwriter. You could free up to 20% of your secretary's time! And when you need a typewriter, CP/M computer, and an intelligent terminal, think of the Wangwriter too. Call Compumart today for configuration help. PHONES: open EST Mon.-Thurs. 8:30-7:00, Fri. 8:30-6:00. PURCHASE ORDERS: Accepted from Dun and Bradstreet rated companies— shipment contingent upon receipt of signed purchase order. SALE PRICES: Valid for month of magazine date only— all prices subject to change without notice. ANN ARBOR RETAIL STORE HOURS: Tues. -Fri., 11:00-7:00, Sat. 10:00-5:00, closed Mon. HELP IS COMING FOR ALL PERSONAL COMPUTER OWNERS: Stop going broke buying software and hardware to find out it's not what you want! The Personal Computer Owners Directory can eliminate a lot of wasted time and aggravation. Through the use of the directory, you can become aware of people in your area and nationally who have the same system or interests. Find out what is worth buying before spending your $$$$. The directory will be listed by cities and interests (e.g.) Games, business, art, robotics, education, etc.) To have your information listed and place your order for the Directory, SEND $19.95 ppd (check or money order) plus the following: Name, Address, Computer Type, Interests, will you help others, are you willing to trade information? Plus any other vital information. If you want your name entered, but do not wish to receive a directory, send $1.00 and the above info. The directory will be open for listings until May 1, 1982, at which time it will go to print. MASS. residents add 5% sales tax. PERSONAL COMPUTER OWNERS, INC. P.O. BOX 426 FEEDING HILLS, MASS. 01030 (413) 789-1555 TO CASSETTE PLUG TO TELEPHONE DATA ACCESS ARRANGEMENT Figure 13: The TELDIL circuit is mounted on a project board. The relay leads can be trimmed, "built-up" with solder, and pushed into the project-board holes. -10 BITS /CHARACTER TYPICAL. - CHARACTER SHOWN IS ASCII "1" ^START BIT =0 +3 TO +15V (0 LEVEL) WM///&////#////A(//ffl///////////A -3 TO -15V 11 LEVEL) j | |_ -H- I //////////// //////////// //////////// --3V TO +3V SIGNALS NOT RECOGNIZED STOP BIT J 4 Figure 14: Logic is inverted in standard RS-232C signals. A 1 is represented by a negative voltage; aO by a positive voltage. Voltage levels from —3 to +3 Vwill not be recognized as legitimate values. 178 April 1982 © BYTE Publications Inc WESTICO-The Software Express Service that really delivers: IISOFTWARE IIIIFOR I HI/PROFESSIONALS The day is fast approaching when computers will be as commonplace as the office water cooler. The Westico software specialists offer a variety of programs to meet the needs of the professional looking for efficient solutions to a variety of tasks. In addition to quality soft- ware, you can count on the Westico experts for help and advice. Here's just a sample of the more than 150 quality programs currently in stock: MicroGANTT — Sophisticated project planning system which uses Critical Path Method analysis, Interactively defines tasks which comprise a project and displays a Gantt chart of the resulting plan. Budget costs and work hours are also calculated and displayed automatically. An entire project can be included in a more global project as a single task. All data is easy to modify and can be dis- played or printed. Available for IBM Personal Computer and CP/M compatible computers. $395/$25. PTA — Professional time accounting for billing based on time. Maintains client master files, work in progress files, employee history files and detailed job files. Produces detailed accounting reports for manage- ment. $595/$40. MILESTONE™ -Critical Path Method project management. Displays and prints project plan in a summary cost/time table, by task or as Gantt charts. Project assumptions are easily revised to make "What if?" analyses. $295/$30. STATPAK — Statistics software library in Microsoft BASIC, Performs probability calculations, one independent variable statistics, discrete distribution functions, continuous distribution functions, regression analysis, means testing, survey data/contingency tables, non-parametric statistics and analysis of variance. Includes plotting and file management modules. $500/$40. — For law offices with up to 25 attorneys and a total of 35 time- keepers (including paralegals, secretaries, etc.). All time and expenses are distributed to client accounts or other designated over- head accounts. Produces monthly client review sheets and ready-to- mail itemized bills. $895/$40. SUPERCALC™ — Makes it possible to manipulate numeric data quickly and easily, Spreadsheet simulator lets you examine and alter numbers and texj- within a grid that can cover up to 63 columns and 254 rows of data. Produces hardcopy reports. $295/—. MINIMODEL™ — Financial planning tool. Does big financial planning jobs at micro prices for cash flow projections, financial forecasting, venture analysis, project planning and risk analysis. Models limited only by disk space. Report content and format totally under user control. $495/$50. :■. c ■#■£■*; , r Write Westico, Inc., 25 Van Zant Street, Norwalk, CT 06855. CaH (203) 853-6880, Telex 643-788. Dial-up our 24-hour computer (300 baud) (203) 853-0816. MICRO-TAX— Provides the tax prac- titioner or serious investor with an in-house computerized tax planning and preparation facility Level 1 for individuals $250, level 2 includes state tax interface $1000, level 3 includes partnership forms $750. TARGET™ Planner — Interactive modeling and planning program. Features include matrices up to 1000 elements and IF, THEN, ELSE, GREATER and LESSER conditionals. Commands for MINIMUM, MAXIMUM, AVERAGE and SUM. $195/$25, TARGET Interchange — Enables TARGET Planner to read and write from and to other data bases. $139/$15. TARGET Task — Integrates the procedures of Performance Evalua- tion and Review Technique (PERT) and Critical Path Method (CPM). Manipulates a project schedule to reach a desired completion date, or predetermined expense budget. $329/$25. I • Westico has more than 150 programs for professionals and businesses that use a wide variety of microcomputers includ- ing: TRS-80 Model II, Apple, Vector Graphic, Cromemco, North Star, Micro- polis, Ohio Scientific, Altos, Dynabyte, IBM, Intertec, Xerox, Zenith, Northern Telecom, AVL Eagle and more. We're work- ing hard to be your software company. COD, MasterCard and VISA accepted. Prices do not include shipping and are subject to change. In CT add 7 1 /2% sales tax. All sales final. Manual price may be credited toward purchase of software, Dealer inquiries invited. WES-45 Copyright © 1982 Westico, inc. WESTICO The Software Express Service 25 Van Zant Street • Norwalk, Connecticut 06855 (203) 853-6880 • Telex 643788 Circle 480 on inquiry card. Each byte to be transmitted occurs at asynchronous, or irregular, times. The line is normally at a 1 level. A start bit leads the output and signals the receiving device that data are coming in. Eight data bits follow, with the least significant bit first. A stop bit puts the line at the 1 level after transmission, in preparation for the next character. The spacing for the 10 bits depends upon the transmission rate. Rates of 300, 600, 1200, and 2400 bps (bits per second) represent "bit times" of + 6V TO +12V +6V TO +12V A CASSOUT C> ^START BIT = 8 DATA BITS n> ~7h SGND -Tkxxxxxxxl: STOP BIT = 1- -6V TO -12V Figure 15: The SEROUT project uses an operational amplifier to generate a positive and negative voltage representing RS-232C data signals. Any convenient positive and negative voltage may be used. Listing 6: SEROUT is a Z80 subroutine to perform RS-232C output through the Model I /III cassette port. 9000 9000 9003 9004 9006 9007 9009 900B 900D 9t30F 9010 9012 9014 9016 9018 901A 901C 901D 90 IF 9021 9022 9024 9026 9028 902A 902 C 902E 902F 9031 9033 CD7F0A 54 2600 E5 FDE1 3E02 D3FF FDE5 El 0E00 1820 0608 3E02 CB3A 3001 3D D3FF El 0E01 1B0E 10EE 3E01 D3FF FDE5 El 0E02 1801 C9 9034 2B 9035 7C 9036 B5 9037 20FB 9039 CB49 903B 20F6 903D CB41 903F 20E5 9041 18D1 0000 00100 00110 00120 00130 00140 00150 00160 00170 00 1 80 00190 00200 00210 00220 00230 00240 00250 00260 00270 00280 00290 00300 003 1 00320 00330 00340 00350 00360 00370 00380 00390 00400 00410 00420 00430 00440 00450 00460 00470 00480 00490 00500 00510 00520 00530 00540 00550 00560 00570 00580 00590 ORG 9000H ; #*#♦##*##******#**#***###****#***#**#*****#*#*********** ;» SERIAL OUT THROUGH CASSETTE PORT. * ;* ENTRY: H=BYTE TO BE TRANSMITTED * ;* L=BAUD RATE: 300=201 » 600=100? 1200=5 1 t * I* 2400=23 (MOD I)/ 230*115, * *# 58,26 (MOD III) * ;* EXIT: AFTER OUTPUT * SEROUT CALL 0A7FH LD D,H LD H,0 PUSH HL POP I Y LD A, 2 OUT (0FFH)t A PUSH IY POP HL LD C,0 JR DELAY SER040 LD B»8 SER050 LD A»2 SRL D JR NCSER055 DEC A SER055 OUT <0FFH)»A PUSH IY POP HL LD C» 1 JR DELAY SER060 DJNZ SER050 LD A* 1 OUT (0FFH) T A PUSH IY POP HL LD C»2 JR DELAY SER070 RET *CNT IN MICROSECS HL A»H L NZi DELAY 1. C NZ,SER070 0iC NZ*SER060 SER040 ; DELAYS 14.6 DELAY DEC LD OR JR BIT JR BIT JR JR END ;GET PARAMETERS 5 MOVE DATA TO D ;HL NOW HAS DELAY CNT ; TRANSFER CNT TO IY ; START BIT ; OUTPUT ; DELAY CNT TO HL ;FLAG FOR RTN • DELAY ONE BIT TIME 8 SETUP DATA BIT LOOP ■0 BIT TO A ;SHIFT OUT DATA BIT ;GO IF DATA BIT=0 5 DATA BIT=1 ; OUTPUT ; DELAY CNT TO HL ;FLAG FOR RTN S DELAY SLOOP IF MORE BITS ;STOP BIT ! OUTPUT ; DELAY CNT TO HL 5FLAG FOR RTN ! DELAY ! RETURN TO BASIC (MOD I ) + OVERHEAD ; DECREMENT DELAY COUNT ;TEST HL lLOOf IF NOT DONE STEST FOR RTN PNT 2 5 GO IF RTN PNT 2 iTEST FOR RTN PNT 1 ?GO IF RTN PNT 1 ;RTN PNT 3.333, 1.666, 0.833, and 0.416 ms, respectively. The chief problem now is to con- vert the low voltage levels of CASSOUT into the two RS-232C voltages. This is done with an LM741 comparator, as shown in figure 15. The supply voltages used with the comparator are +6 to +12 V and —6 to —12 V. Batteries will work fine, and the voltages are not critical. The voltage-divider input to the plus (" + ") input of the LM741 is biased at about (220/15000) X V + , where V+ is the positive supply voltage. This puts the plus input at about 1/10 V for a +6-V supply, or about 1/20 V for a +12-V. The out- put of the 741 will be -6 to -12 (1 level) whenever CASSOUT is greater than the plus input level, and +6 to + 12 V (0 level) whenever CASSOUT is less than the plus input level. BASIC initializes the port control- ling CASSOUT to binary 00 (0.44 V), and so the TD (transmit data) line at reset is normally —6 to —12 V. By toggling the CASSOUT line at the ap- propriate rate, you can generate the RS-232C signals, SEROUT (see listing 6) is a relocatable assembly-language pro- gram called from BASIC by a USR call. Two parameters are passed: the byte to be transmitted and the transmission rate to be used. The byte can be any value from through 255. If seven data bits are to be transmit- ted (as in data-communications ap- plications), make the eighth bit 0. SEROUT first picks up the trans- mission-rate code and puts it into the HL register pair. The code is a delay count for the DELAY subroutine. The byte to be transmitted is moved to the D register. Line 260 turns on CASSOUT to generate a start bit. A delay of one bit time is then done. The loop from lines 320 through 410 outputs the eight data bits, from least significant to most significant. A 1 bit is generated by sending a 01 to port OFF hexa- decimal, and a bit is generated by sending a 10. A duration of one bit time is used for each bit. A stop bit is generated in line 430 after the eight data bits. This leaves the TD line at the 1 level in prepara- 180 April 1982 © BYTE Publications Inc tion for the next start bit. The DELAY subroutine is called by relative jumps with a return flag to keep the code relocatable. Listing 7 shows a sample BASIC driver that contains the machine code for SEROUT as DATA statements. The code is relocated to start at 9000 hexadecimal. For demonstration, an ASCII is continually output at a user-specified rate. The actual BASIC code to be used depends a great deal upon the ap- plication. If you are using SEROUT Listing 7* A sample BASIC driver for the SEROUT subroutine. The DATA statements contain machine-language codes for the subroutine. This program outputs a continuous stream of ASCII zeros. I 819 110 i m I 30 J 40 ■ 1 70 1 80 190 2m 210 220 230 24@ 250 DA i A ■■ Bi - ■■- 20 ii DATA ;■'■'- . ' • \ DATA 62 1 li .: Ui DATA J i :Vi J s 43i 1 24, , ,'C'i h 65? ■■ ■ FOR I= :: -36864 TO 36930 READ AsPOKI I ■ •' 3 ?i >i A NEXT I DEFU3R0-&H9000 INPUT "RATE?" ;RT CH=48 B»USR0 ( CH*236+RT ) GOTO 240 RADIO SHACK 276-175 EXPERIMENTER SOCKET WIRING DIAGRAM (SEE FIGURE 6) -6V TO -12V © Figure 16: The SEROUT circuit is mounted on a project board. Two sets of power- supply connections are required. ./jV MicroGANTT is a ^J^^ sophisticated project p planning system which uses Critical Path Method (CPM) techniques and PERT to determine task dependencies and project completion dates. The user creates tasks, assigns costs and detines task depend- encies. The interactive system immediately redisplays the proj- ect plan as data is entered. Projects are displayed as Gantt charts, labor time summaries and financial summaries. MicroGANTT features: Time scale of days, weeks, months, quarters or years can be varied at any time to present more or less detail, Accommodates unlim- ited number of tasks in a project plan. Detailed sub-projects can be included as tasks in a project model. Assumptions are easily modified to make "What if?" analyses. Single key-stroke com- mands page through tasks and calendar of events on display screen. Single key-strokes switch the display from Gantt chart to labor time summary to financial summary. Partial allocation of manpower to tasks. Partial completion of prerequisite tasks. All charts, reports and plans can be printed. Available for IBM Personal Computer and CP/M compatible computers. Software and manual $395. Manual alone $25. • Write Westico, Inc., 25 Van Zant Street, Norwalk, CT 06855 • Call (203) 853-6880 • Telex 643-788 • Dial-up our 24-hour computer (300 baud) (203) 853-0816 copyright € 1982 Westico, inc. WES-44 WESTICO The Software Express Service April 1982 © BYTE Publications Inc 181 NEC CABLE FROM SEROUT CIRCUIT TD TIE THESE PINS TOGETHER ^-^ 4 5 3 6 8 20 7 v^ \ RD GND \ \ SGND Figure 17: / connected an NEC Spinwriter to the SEROUT circuit with two wires and some "jumper" interconnections on the Spinwriter side. Other RS-232C devices will re- quire similar connections. as a printer driver, you'll have to make certain that the printer can ac- cept characters at the rate you'll be transmitting. This is usually not a problem except on carriage re turn /line feeds where the print mechanism is busy for relatively long times as the carriage returns. If a character is output during this busy condition, it may be disregarded and lost. The bit-delay times shown are values obtained by trial and error with the real-time clock active. You may have to adjust these on an ex- perimental basis, depending upon your system. Output a line of characters continuously at different bit rates. Find the high and low values at which you start to lose characters and choose a midpoint value for your standard bit rate. For high bit rates, turn off the interrupts using DI and EI as described in TONOUT. Constructing the Electronics Figure 16 shows the project-board layout for SEROUT. Two sets of power-supply leads connect to the positive and negative supplies. The TD line and ground connect to the serial device. The serial device may require other signals to be tied high to simulate a "ready" condition. Again, this depends upon the device and can't be detailed here. A typical connection to an NEC Spinwriter is shown in figure 17. The projects presented here show what can be done with the cassette output port on a lowly 16K-byte TRS-80 Model I without an expan- sion interface. I'll cover transmission in the opposite direction — CASSIN — in another article. Perhaps by then the breeder reactor program will be working for CASSOUT. Hmmm . . . I keep getting these "Coolant Temperature Critical" indica- tions. . . . ■ Expand Your IBM Personal Computer O Memory Expansion Board. Datamac's Expansion Board offers 4 TIMES the amount of memory offered by the IBM PC. Configurations can be set at 64K, 128K, 192K and 256K bytes. Board can be upgraded at 64K capacities. O Winchester Disk System. Priced 30% lower than competitive systems, Datamac's Winchester Disk System is housed within the IBM chassis and is easy to install directly into the floppy disk slot. The Datamac Memory Expansion Board for the IBM Personal Computer is available through participating Computerland Dealers. Peripheral Products Division, 680AlmanorAve., Sunnyvale, CA 94086, (408) 735-0323 datS l n ac 182 April 1982 © BYTE Publications Inc Circle 137 on inquiry card. T O RUN NON-STOP Smoke Signal's Chieftain™ computer series: The kind of tough reliability you need today your business team. eftains are preferred by discerning buyers when extra performance has : delivered under less-than-ideal operating conditions. The track record i computer has achieved in hundreds of demanding installations world- wide is proof that a Chieftain can meet any challenge your business vironment has to offer. Meet from a family of field-proven systems. Chieftains range from floppies to this 5 1 /4-inch Winchester hard disk system with 20- meg a byte tape streamer option. It's available with the new OS-9 Level I and II, multi-user, UNIX comparable operating system for mainframe-like performance. A., 6809- based Chieftains deliver six months of continuous operation at Arctic Circle Two Chieftains accompanied an Adak research expedition during the frigid winter of 1981. The computers fulfilled a vital support role for an earthquake prediction study. In sub- zero temperatures, rairi snow, ice and wind-driven weeds and dust, the extraordinary Chieftains — supported by Smoke Signals factory-based staff — proved they were up to the challenge. Chieftains are so cost-effective and advanced, they obsolete most other systems available today at any price. t:ther you select an upward-compatible 5'4- or 8-inch floppy disk system, or 5 l A- or 8-inch hard disk configurations of 4- to 60-megabyte acity, you'll receive Chieftain's widely acclaimed quality — plus value that makes your dollar go a lot further. Smoke Signal's huge software array begins at comprehensive business programs, and expands into esoteric applications for rare and specialized tasks. ling of the latest additions to the Chieftain hard disk computer systems that are destined to change the way you think about data THE CHIEFTAIN 95W4 4-megabyte, 5^-inch Winchester floppy disk drive □ THE CHIEFTAIN 98W15 1 5- megabyte, 5 '/vinch Wi rich ester with a ! -megabyte 8- inch floppy disk drive □ THE CHIEFTAIN 95XW4 4 megabyte, 5 '4- inch Winchester with a 750- k octo-density floppy disk drive □ THE CHIEFTAIN 9W15T20 15- megabyte, 5ft- inch Winchester with a 20-megabyte tape streamer DR CALL TODAY FOR DETAILS ON THE TOTAL CHIEFTAIN SERIES ... AND ON DEALERSHIP OPPORTUNITIES STILL AVAILABLE «ce Signal Broadcasting • 31336 Via Colinas, Westlake Village, CA 91362 • (213) 889-9340 l .„. _ ._, „ I Name.. Title _ SMOKE SIGNAL * Chieftain Computers For dealers only, circle 375 All other inquiries, circle 455 Company . Address City State- .Zip. Green phosphor screen H*gh resolution (720h" 350v) Lpper/Iowercase 80 characters x 25 lines adapter \ iZ'£*~f ? •• i m integrated speaker tU^I RS232C interface UP to 9600 bits per second 6 cord to system unit 16 colors -'56 characters in text ^.graphics modes Simultaneous graphics and text capabilin PlCS ■\. :v r B i. f» Junction keys l °-key numeric pad System expansion * J* 2 optional internal v diskette drives j^^ *' /? v r 1 8088 microprocessor Parity checking 40KB in ROM 160KB per 5'/V' diskette User memory' expandable up to 256KB , Because we put what you want into it, you get what you want out of it. We unwrapped our package for you, bit by bit. It's all here. And you're looking at it. From the 8088 microprocessor and the Macro Assembler that give you speed and capacity to the RS232C interface that gives you the world. All told, no other personal computer offers as many advanced capabilities. Read all about them in the Technical Reference Manual available at your IBM Personal Computer dealer. Software? IBM Personal Computer DOS. The UCSD p-System. Plus a documented set of our device driver routines. For high level languages, exactly what you want. Enhanced BASIC in ROM. Pascal. FORTRAN. But our software story is still being written. Maybe by you. If you're interested, start by writing to: IBM Personal Computer Software, Dept.765, IBM Corporation, Armonk, New \brk 10504.===:==:® The IBM Personal Computer Circle 200 on inquiry card. The Input /Output Primer Part 3: The Parallel and HPIB (IEEE-488) Interfaces An introduction to two common interfaces between computers and other devices. Steve Leibson Auto-Trol Technology Corporation 12500 North Washington St. POB 33815 Denver, CO 80233 This article is the third in Steve Leibson's six-part series, The Input/ Output Primer. The series describes problems involved in communications between computers and the outside world and explains how some of these problems have been solved. The three remaining articles will discuss BCD and serial interfaces; character codes; and interrupts, buffers, grounds, and signal degradation. "An I/O Glossary," which defines many terms used in these articles, appeared with the series' first installment (February 1982 BYTE, page 122). Last month, in addition to describ- ing interrupts and DMA (direct memory access), I presented general information about interfaces. In this article, I'll examine two specific types of hardware interfaces: the parallel and the HPIB or GPIB (IEEE-488) in- terfaces (see Robert Katz's review of the Hewlett-Packard Interface Loop, page 76). First, however, let's briefly review why these interfaces are necessary. As information-processing machines, computers require paths for raw data to enter and for processed informa- tion to exit. A common computer- design technique is to create one universal path leading both into and out of the processor. That path is the Data Inversion occurs In software, not In the Interface. I/O (input/output) bus. This concept simplifies computer design but introduces a complication: whatever the design of the I/O bus, the computer will be incompatible with many I/O devices. Some older devices use different signal levels; other devices have different data for- mats. Most devices will be slow enough to degrade the computer's performance seriously if it must wait on every data transaction. The complication is solved through the use of interfaces, which act as transformers of voltage levels, data formats, and transaction speeds. In- terfaces enable the computer to com- municate with a vast array of peripheral devices. The Parallel Interface Simple peripherals often have in- terface requirements much like those of the computer's I/O bus. Data is transferred over a set of data lines (usually 8); a signal line indicates when the next chunk of information is ready. On a second signal line, the peripheral indicates its readiness to accept another piece of data. This type of interface is a parallel interface, so named because the data lines are parallel, and multiple bits of data are simultaneously transferred in parallel. The HP 98032 A is a parallel interface designed for Hewlett- Packard's 9800-series computers. The I/O bus described in earlier in- stallments of this primer was taken from the 9800 computer. I'll use the 98032A 16-bit interface as an example of parallel interfacing. Keep in mind that the I/O bus has 16 bidirectional data lines. Data is handled in 16-bit chunks and flows 186 April 19S2 © BYTE Publications Inc THE FORMULA™ allows the computer professional to focus on the most important part of business: the needs of the client. 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MasterCharge and VISA accepted. New York State residents add appropriate sales tax. *CP/M is a trademark of Digital Research. Circle 210 on inquiry card. Main/Frames Main/Frames from • 30 Models of Enclosures • Assembled and tested • Quasi-Coax Motherboards • Power Supply • Card cage and guides • Fan, line, cord, fuse, power & reset switches 8" Floppy Main/Frame 8" Disc Enclosure Phase/80 8" Floppy Mainframe Phase/80 Desk + Mainframe Write or call for our brochure which includes our application note: "Building Computers — A Recipe" INJEGB4ND 8620 Roosevelt Ave. • Visalia, CA 93291 209/733-9288 We accept BankAmericard/Vlsa and MasterCharge 16 TO Bit PERIPHERA ^ 16 A. BIDIRECTIONAL^ L V ~t7~ OUTPUT REGISTER 7*T -\ oui -J LIN OUTPUT ES 16 \ IN J RE PUT EGISTER u -?"S~ -) INP S LIN PUT ES STROBE ■ I/O FLAG STATUS CONTROL CIRCUITRY ^ DATA LINES TT c <^ PERIPHERAL ADDRESS LINES" Figure 6: Block diagram of the Hewlett-Packard 98032 parallel interface. The parallel interface consists of registers and buffers. One register is for output, the other for input. The 32 unidirectional lines can be used as one set of bidirectional lines. If a peripheral has a bidirectional interface, these two sets of lines can be connected to form a bidirec- tional peripheral bus. Control circuitry in the interface accepts information from the computer and then sends the information to the peripheral. The same control circuitry can also, at the request of the computer, request information from the peripheral, then signal the computer when the information has been acquired. over these lines either into or out of the computer, but not in both direc- tions at the same time. The 98032A interface splits the I/O bus into two sets of data lines: 16 out- put lines and 16 input lines (see figure 6). This configuration is more com- patible with unidirectional periph- erals. Excess lines are left uncon- nected. Out of 32 data lines, only 8 might be used by a unidirectional, 8-bit peripheral. As mentioned above, interfaces sometimes serve to transform the sig- nal voltage levels used on an I/O bus to those required by a peripheral. Our sample I/O bus uses TTL (tran- sistor-transistor logic) levels, mean- ing that a low logic level is repre- sented by a voltage between and + 0.7 volts (V). A high logic level is represented by a voltage between + 2.0 and +5.5 V. The input lines of the 98032A parallel interface connect to TTL circuitry in the interface, so TTL levels are required from the peripheral. The data output lines of the 98032A are driven by transistor circuits that can withstand + 30 V for a high level. The low level is still be- tween and +0.7 V for TTL com- patibility. Remember that when discussing logic signal lines, only two signal levels are allowed. One level cor- responds to a logic 1 and the other to a logic 0. If the higher voltage cor- responds to a logic 1 and the lower level to a logic 0, the signals are said to be positive-true . If the lower voltage level corresponds to a logic 1 and the higher voltage to logic 0, the signal is called negative-true. To sum up: 1. I/O bus lines are the conductors used to transfer data between the computer and the interface. 2. Interface input and output lines are the conductors used to transfer data between the interface and the peripheral. 188 April 1982 © BYTE Publications Inc IBM'S DOS or CP/M-86? Confused about operatins system options for your IBM Personal Computer? HAVE IT BOTH WAYS WITH LIFEBOAT'S CP/EMULATOR™. CP/EMULATOR solves the problem by permit- ting you to use all the software written for IBM's PC for both DOS and CP/M-86. This high performance, low cost DOS utility al- lows you to fully integrate and mix programs. 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Copyright © 1981, by Lifeboat Associates a LIFEBOAT HAS THE ANSWER t3 (la) Input Registers Register Code R4 R5 R6 R7 (lb) Output Registers Register Code R4 R5 R6 R7 Function Data Input Interface Status High Byte Data Input (Not Used) Function Data Output Interface Control High Byte Data Output Data Transfer Trigger Table 1: Interface definitions for the 98032 A parallel interface. Table la defines the input registers, and table lb defines the output registers. Register Architecture I stated earlier that each interface would have a unique address on the I/O bus and would be selected by the peripheral address line on that bus. Each interface is divided into registers that are individually addressable by means of a register code. The register model divides the interface into eight different registers. Four of these are output registers that take data from the computer (the computer outputs to them). The other four are input registers, supplying data to the com- puter (the computer gets input from them). Let's now assign a function to each of these interface registers. The 98032A interface uses the definitions shown in tables la and lb. R4 registers are the primary means of data transfer between the com- puter and the interface, and in turn, the peripheral. The R4 output data register is directly connected to the output signal lines of the 98032 A. The R4 data input register is connected to the interface input lines. The R6 input and R6 output registers allow the 98032A to be used as two 8-bit inter- faces instead of one 16-bit interface, The R6 registers read or control the upper eight data lines when the inter- face is in the byte mode, that is, when the interface is handling data in 8-bit Olympic Sales A SERVING YOU SINCE 194/ Company CABLE: "OLYRAV" LSA Main Showroom & Offices: 216 So. 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Circle 99 on inquiry card. • - , ", ■■ : ?: ■ ,■ ' - . 4; : ; ■■ ■ - ■ i .■■ ; v ■■■ Interface Board for Applet is available now, 8NM400CLU BIVH40tHG8 B&M402BO6 PhosphorCRT 13** Composite Video Signal 13" RGB Separate Video Signal 13" RGB Separate Video Signal tfdeoSigna! 40Char,x2SUr 5 x 7 Dots, 40 Char. X 25 Lines 5X7 Dots, 80 Char, x 25 Lines ! Lines . . • - . ■HHi INTERFACE ACKNOWLEDGES REQUEST I/O BUS FL6 LINE HIGH LOW f PCTL CONTROL CLEAR CONTROL SET BUSY PFLG CAUSES J COMPUTER REQUESTS TRANSLATION PERIPHERAL ACKNOWLEDGES REQUEST X ! REQUEST FULFILLED Figure 7: Representation of the handshake between the HP 98032 parallel interface and a peripheral device. When the computer requests a transaction, the interface uses the FLG line on the I/O bus to signal the computer that it's busy. Then, the PCTL (peripheral control) line is set to request an operation by the peripheral Later, the peripheral acknowledges the request by setting the PFLG (peripheral flag) line to busy. When the peripheral completes the transaction, it sets the PFLG line to ready, causing the interface to lower the I/O bus flag line and thereby tell the computer that the transaction is com- plete. This sequence governs both input and output. Direction lines between the com- puter, the interface, and the peripheral determine the direction of the transaction. version occurs in software, not in the interface. The computer may choose to ignore these status bits for certain classes of I/O operations. Other in- terfaces may implement data inver- sion in hardware so that, if selected, the inversion will always occur. The two remaining bits in the inter- face status register, STIl and STIO, are status inputs brought out on two signal lines. The peripheral can call on these for any user-defined func- tion. Unlike the R4 input register, the STIl and STIO bits reflect the current state of the STI signal lines. Interface control is through the R5 output register. Table 2b lists the bit pattern for this register. The INT and DMA bits are used in the interrupt and direct memory access modes mentioned earlier. The RESET bit is used to place the interface in the in- itial power-up state. It can also be used to reset the attached peripheral to a known state if the peripheral has a reset input. I/O processes often stall, for example, when the printer runs out of paper or a disk drive door is left open. A reset capability allows the computer to change its mind and stop what it has started. The AHS bit enables auto-hand- shake. When this bit is set, the data- transfer trigger (R7 output) isn't needed. This characteristic is conve- nient for high-speed transactions and is habitually used with DMA, Bits 3 and 2 are unused in the R5 output register. CTLl and CTLO are general-pur- pose control bits. These register bits are connected to two signal output lines and can be used to control the attached peripheral device. A signal over these output lines can be given to latch a printer door shut while printing is taking place. Peripheral Handshaking Note that the R7 output register is called the data-transfer trigger. When used in conjunction with the R4 input and output registers, the data-transfer trigger forms a handshake mechanism that synchronizes the fast computer and the slower peripheral. Placing data on the output lines or reading the levels on the input lines connecting the interface to a peripheral device isn't sufficient for smooth data flow, A set of signals in- dicating "new data available" and "ready to accept data" is needed. These signal lines are called hand- shake lines. The interface and the peripheral each control a handshake line. The meaning of the signal for each line depends on the direction of data flow. If the computer is sending through the interface to the peripher- al, the line controlled by the com- puter means "new data available." The line controlled by the peripheral would then signify "ready for new data." If the data flow is reversed, the signal meanings are also reversed. Let's call the line controlled by the interface the peripheral control (PCTL) and the line controlled by the peripheral the peripheral flag (PFLG). With the addition of these two lines, the foundation is laid for discussing the handshake mechanism. Data Output Output is simpler than input. As has been mentioned, the computer can set the state of the interface out- put lines by placing information in the R4 output register. The hand- shake is started when the computer performs a write to the interface's R7 output register. The interface recognizes the data- transfer trigger and responds by changing the state of PCTL from "clear" to "set," which indicates to the peripheral that "new data is ready" on the interface's output lines. The peripheral is expected to acquire the data now. The peripheral responds to "new data ready" by changing PFLG from the "ready" to "busy" state. This means the peripheral is busy accept- ing the data. From the time the computer per- forms the R7 output register write un- til the time the peripheral returns to a "ready" state after processing the data, the interface is busy carrying out the transfer. It's extremely impor- tant that the computer not change the R4 output register during this time. Otherwise, there's no way to tell what data the peripheral will get. For this reason, the interface and the computer also have a handshake mechanism. While the interface is busy sending the information to the peripheral, the interface indicates this situation to the computer on the in- terface flag line. Figure 7 illustrates the peripheral-interface handshake. 194 April 1982 © BYTE Publications Inc Toughest Boards in Town... IEEE696/S-100. Systems too! 256 Kb Dynamic Memory Available now from Dual Systems: DMEM/ 256 memory boards. 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In California call 415-376-9020. Assembly, integration and testing also available from our service department. Ask about our Leasing Program. We are buying agents for overseas computer dealers. EXPORT SERVICES available. International Telex 470851. Mastercard, VISA at 3% handling fee. Prices subject to change without notice. Minimum fee $ 100. 15% cancellation fee. THE PURCHASING AGENT 1635 School St., Suite 101, Moraga, CA 94556 Vector 2600 4,221.00 Vector 3005 6,458.00 Vector 5005 7,308.00 Wicat CALL Xerox8205U 2,300.00 Xerox 820 8" 2,900.00 Printers AnacomlSOCPS 1,112.00 C.ItohF-10 1,400.00 C.Itoh 40 CPS Serial 1,500.00 C.Itoh 45 CPS Par 1,675.00 C.Itoh Comet II 800.00 Diablo 630 1,965.00 IDS 560 1 ,099.00 IDS Prism 1 32 Column 1,395.00 Malibu200 2,320.00 NEC 35 10 1,830.00 NEC 7710 R/O 2,250.00 NEC 7720 KSR 2,700.00 NEC 8023 603.00 Olivetti 231 2,104.00 Qume9/35 1,795.00 Oume9/45 2,095.00 Sellem 1 2,725.00 Tally CALL Others Anderson Jacobsen 641.25 Houston Instrument DMP-2 1,147.00 Houston Instrument DMP-4 1,460.00 Houston Instrument DMP-7 2,077.00 Data Input Data input from a peripheral is more complex. Three steps are in- volved. First, the computer reads the R4 input register to let the interface know that a data-input operation is pending. (The computer throws away the data obtained.) The interface recognizes this and indicates the situation to the peripheral with a data-direction line (this line tells the peripheral which direction the data is to go). Next, the computer writes to R7 output, giving the data-transfer trig- ger. This causes the interface to go busy and to place the PCTL signal line in the "set" state, signifying to the peripheral that data is requested. The peripheral then goes busy until it has acquired the data. It signals its busy state on the PFLG line. After the peripheral performs the operations necessary to get the re- quested data, it places the data on the interface input lines and returns PFLG to the ready state. When the periph- eral returns to the ready state, the transition of the PFLG signal from "busy" to "ready" causes the data on the input lines to be placed or "latched" into the R4 input register. This causes the interface to signal the computer that the interface is now ready with the requested data. The computer then performs another read from the R4 input register to get the data. Note that the R4 input register con- tains the information present on the input lines at the busy-to-ready tran- • sition of the PFLG line, Any changes on the input lines after that transition will not be reflected in the R4 input register. Notice also that the peripheral-interface handshake for in- put is the same as that for output. Some peripherals, by the way, are so simple that they can't perform a handshake. An example of this would occur if the 98032A were used to drive signal lights directly. Lights have no handshake lines. They always follow their data (power) in- puts. In these instances, you can con- nect the PFLG and PCTL lines to each other so that the 98032A handshakes with itself. This results in 16 "latched" output lines and 16 input lines that 196 April 1982 © BYTE Publications inc Circle 341 on inquiry card. The Guesswork Is Gone! Thanks to Strictly Soft Ware. Consider the care you invested in buying your computer. We've done the same for your software. How many times have you won- dered: Is the package right? The price? The service? We've cleared a course for y<5u to the best software — quality and price. Strictly Soft Ware brings you the best in entertainment, education, per- formance, and price. Take a look at the offerings below. And call now (toll-free) for our free catalog. $19.95 SPECIALS $19.95 SPECIALS • Track Attack • Red Alert • Apple Panic • Midnite Magic • Space Eggs • Sneakers • Beer Run • Dark Forest • Ulysses • Jawbreaker • Crossfire • Sabotage • ABM • Castle Wolfenstein • Robot War • Three Mile Island Arcade Games ABM Apple-oids Apple Panic Autobahn Beer Run Bug Attack Compucube Computer Air Combat Computer Baseball County Fair Crossfire Cyber Strike Dark Forest Dogfight Epoch Firebird Flight Stimulator Gamma Goblins Genetic Drift Gobbler Golden Mountain Gorgon Hadron Hi Res Soccer Intl Gran Prix Missle Defense Mouskattack Olympic Decathalon Orbitron Outpost Pool 1.5 Pegasus II Phantoms Five Pulsar II Raster Blaster Southern Command Magic Window Reversal Space Adventure The Mail Room Robot War Swordthrust The Merger Ruski Duck Talawa's Last Redobtd Menu Generator Snack Attack Stone of Sisyphus Micro Courier Sneakers Tarturian PFS Super Invaders Temple of Apshai PFS Report Star Thief The Terrorist Real Estate Analyzer Space Eggs Time Zone Spellstar Space War Ulysses/Golden Fleece Superscribe II Space Quarks Ultima Super Text II Thief Wizard/Princess TASC Compiler Three Mile Island Wizardry Tax Manager Threshhold Zork Tax Preparer Track Attack Versaform Trick Shot Business Visiblend Warp Attack Accounting Visicalc 3.3 Adventures BPI Continental Visidex Visifactory Adventures 1-12 Peachtree Visifile Alkemstone Broderbund Visiterm Akalabeth The Apple Speller Visitrend/Visiplot Adventure to Atlantis Castle Wolfenstein ASCII Express Creative Financinq Wordstar Z-80 Cards Crush, Crumble, Chomp Cyborg Galactic Empire Lords of Karma Creature Venture Mystery House Napoleon's Campaigns Oldorf's Revenge 00 Topos The Prisoner Race for Midnight Data Capture Data Factory DB Master DB Master Utility Desk Top Plan II Easywriter Eduware Financial Partner Graphtrix Letter Perfect Magic Spell Home/Personnel Decision Master The Correspondent Diet Planning Financial Management System II Home Money Minder Mastertype Above titles are partial selection. Call for prices and catalog. VISA' We take Master Card or VISA (include card § and expiration date). Ohio residents add 5.5% tax. Include $2.00 for postage. Send for free catalog. Prices subject to change. Strictly Soft Ware Post Office Box 338 Granville, Ohio 43023 order by phone 800-848-5253 in Ohio 614-587-2938 Circle 388 on inquiry card. BYTE April 1982 197 may be read on demand. Most peripherals using the parallel interface use only 8 bits. This allows 256 combinations (2 8 ) on the data lines. If these combinations are treated as codes representing charac- ters, then 8 bits can represent numerals, upper and lower case let- ters, punctuation marks, and other printable characters. Most periph- erals communicate this way, but there are exceptions. A floppy-disk drive may require the full 16-bit inter- face. Some plotters use 12 bits. Analog-to-digital converters come in 10-, 12- or 16-bit sizes. A single 16-bit interface can serve all these kinds of peripherals. The IEEE-488 Standard Interface Computer designers strive to incor- porate the latest parts and the fastest logic in new and different configura- tions. In addition, designers of com- puter peripherals are always creating new classes of devices. The result has been a multitude of interfaces, each optimized for a single kind of com- puter or peripheral. Few of these in- • • •FEATURING 8 and 16 BIT S-100 SYSTEMS* * * WE OFFER A WIDE RANGE OF CRTs, PRINTERS, GRAPHICS EQUIPMENT, SOFT- WARE FOR ALL SYSTEMS. EACH SYSTEM IS COMPLETELY TESTED, INTEGRATED AND READY FOR PLUG-IN OPERATION WHEN YOU RECEIVE IT. WE TAILOR & CONFIGURE SYSTEMS TO MEET YOUR BUDGET AND NEEDS. WE WELCOME YOUR REQUEST FOR TECHNICAL INFO BY PHONE OR LETTER. CROMEMCO: Sale! 25% off systems/ software; 15% off boards/ components. SYSTEM I: Low priced small system with 5MB hard disk $5,246. SYSTEM I W/O hard disk. . .$2,996. Cromix multi-user systems starting at $4,713. High resolution color graphics hard disk system Model Z2HGS $10,875. NEW SYSTEMS FROM IMS 2 yr warantee on boards! Integrated system with § built-in monitor, detached keyboard, 5 l A" drives. Systems w/8" drives, optional 10,20 or 40 MB Winchesters, built-in tape back up, multi-user capability (TURBODOS or MP/M). Z-80, S-100 bus. Over 150 configurations to match your specific needs. On site service contracts for NY tri-state area. SEATTLE 8086 SYSTEMS Featuring 86-DOS, the IBM PC Operating System. System I: 8MHZ CPU set w/1 serial, 1 parallel I/O (additional I/O option) 64KB 16 bit Static RAM, Tarbell DD controller, TEI 22 slot mainframe w/constant voltage trans- former $2,695. System II: with 128K Static RAM $3,550. Interfaced to dual Shugarts 801 $1,275. or dual QUME DT-8 $1,680. CALIFORNIA COMPUTER SYSTEMS 2210A High quality, low price. Z80 CPU, 1 serial port, disk controller w/CP/M 2.2 64K RAM $1,650. Add our Max Box w/dual Shugarts or Qumes and IMS I/O w/2 serial, 1 parallel. LOMAS DATA 8088 SYSTEMS same CPU & Operating System as IBM PC. Complete LOMAS card set in TEI 12 slot mainframe, 86-DOS, dual Shugarts, Televideo 912, assembled and tested $4,424. GODBOUT: Complete product line now available. Discount prices. MAX BOX DISK DRIVE SUBSYSTEM mfg by John D. Owens Assoc. Dual drive cabinet w/ regulated power supply, fan, complete internal cabling. Will hold Shugarts, Qumes, Tandons and/ or 8" Winchester, horizontally mounted. Excellent design and engineering. 17 Vi X 5Vz X 22. Attractive buff color. W/2 Shugart 801 $1,275. W/2 QUME DT-8 dble sided drives $1,680. TECM AR 8086 and Z80 Video Digitization systems 5% off list. IBM PC boards and accessories produced by TECMAR also discounted. GRAPHIC SYSTEM: Advertising* Architects«Designers»Package includes powerful interactive graphics software + MicroAngelo Graphics Subsystem + M9900 16 bit, S-100 w/dual 8" floppies, + HIPAD Digitizer + Plotter $10,200. TURBODOS: Spectacular CP/M Compatible Multi-user Operating System. Z80 Code, interrupt driven. Up to 6X faster than CP/M; up to 35% increased disk capacity. Now available for IMS, TRS-80 Model II, CCS & Tarbell controller. Prices subject to change without notice Write or call for free catalogue JOHN D. OWENS Associates, Inc. 12 Schubert Street, Staten Island, New York 10305 212 448-6283 212 448-2913 212 448-6298 I PER SCI: Model 299B $2,760. Model 277 $1,495. Slim line cabinet .... .$325. i terfaces are compatible with any of the others. This situation is similar to that of the American railroads during the early 1800s. Because dozens of track gauges existed, cars of one railroad couldn't travel on the tracks of another. Reminiscent of the speed with which railroads standardized track gauges, the computer industry quickly agreed on an interfacing stan- dard, published in 1975 by the In- stitute of Electrical and Electronics Engineers (IEEE). It was the first com- prehensive, nearly universal interfac- ing standard for computers and in- strumentation. The first version, IEEE Standard Digital Interface for Pro- grammable Instrumentation (IEEE- STD-488-1975) was slightly revised in 1978 and is now IEEE-STD-488-1978. This standard defines a general- purpose interface, one designed for instrumentation systems requiring limited-distance communications. The intent of IEEE-STD-488-1978 (hereafter, "IEEE-488") is to pin down as many variables of an interface as possible while still maintaining good flexibility and wide applicability. The interface is also defined without reference to the hardware circuitry re- quired to implement the interface. This allows new products to take ad- vantage of new technologies, result- ing in faster and less expensive con- struction of instruments, peripherals, and systems. The HP 98032A parallel interface has two separate groups of data lines: 16 for input and 16 for output. This allows interfacing to a wide variety of peripherals with varied interfaces. Devices with 8, 10, 12, or 16 data lines can be accommodated. A popular version of the 98032A has a cable with no connector attached. The system builder must select a con- nector and assign the pin numbering since there are no standards as to how to connect this type of interface. By contrast, the IEEE-488 standard precisely specifies signal levels (both voltage and current) and signal tim- ings, Building a system can be as simple as removing components from their boxes and plugging them in. Interconnection hardware is defined so that two interconnected instru- 198 April 1982 © BYTE Publications Inc ments can communicate. Their understanding each other, however, is not guaranteed by the standard. Using the IEEE-488 standard is like using the international telephone system. You can call anywhere on earth because a compatible com- munications network, the telephone system, exists. Sounds you make can reach the other end of the connection, and you can hear the sounds made by the person at that other end. The hardware for communications is all in place, but there's no guarantee that you'll understand what the other per- son is saying or vice versa. Hardware compatability does not guarantee language compatibility. Hewlett-Packard has an implemen- tation of the IEEE-488 standard which it calls the HPIB or Hewlett-Packard Instrumentation Bus, HPIB is a com- bination of the hardware interface specified by the IEEE-488 standard and a communications technique that makes it possible for instruments to communicate with each other. The standardization also allows the system designer to communicate what's going on in the system. The IEEE-488 standard is so general that almost any peripheral or instru- ment can be purchased in an HPIB version. Voltmeters, power supplies, signal generators, printers, plotters, and disk drives are only a few of the devices available. All may be con- nected on the same bus. Unlike the parallel interface, which connects a single device with the com- puter, the HPIB interface makes it possible to connect as many as 15 devices (including the computer). HPIB is indeed a bus, similar in con- cept to the I/O bus of the computer. Controllers, Talkers, Listeners Only two entities reside on the I/O bus: the computer and the interface. The computer is always in control of the I/O bus, and the interfaces are slaves, doing the computer's bidding. Three types of devices exist on the HPIB: controllers, talkers, and listeners. These types are actually at- tributes and may exist alone or in combination within any given peripheral. For example, the HPIB in- terface allows a computer to be a talker, listener, and controller. A voltmeter may only be a talker limited to supplying the system with information, while a printer may only be a listener limited to accepting data from the system. Further, any of the HPIB attributes may or may not be active at a given time. Figure 8 illustrates how an HPIB system might be structured. The lines on the right of the figure represent the HPIB's 16 signal lines. The 16 signal lines are divided into 3 groups, the first of which is composed of 8 data lines. Forming the data bus, these bidirectional signal lines carry infor- mation and messages between devices on the bus. The second group, the data byte transfer control group, is composed of 3 lines: DAV (data valid), NRFD (not ready for data), and NDAC (not data accepted). As the names imply, this group is used to sequence the flow of information over the data lines. The 5 remaining • •GREETINGS TO OUR FRIENDS IN WEST GERMANY * * HOUSTON INSTRUMENTS PLOTTERS Standard & Intelligent models w/surface areas of SVi" Xll" to 11 "X 17" , Front panel electronic controls. DMP-2 ... $ 935. DMP-3 $1,195. DNHM . . . $1,295. DMP-5 $1,455. DMP-6 . . $1,685. DMP-7 . . . $1,865. HAYES MICRO MODEM 100 $359. Smartmodem . $251. Cronograph $224. EPSON MX 80 $475. MX80F/T $630. MX 100. ... S725. RS232 INTERFACE $ 70. GRAFTRAX..$ 95. 2K BUFFER $140. 3M SCOTCH® Diskettes In storage box 5 box minimum, price per box. 740, 8* ss/sd $29.00 741, 8" ss/dd $35.50 743,8" ds/dd $45.50 744-0, 5 l A" soft sectored or 744-10, hard sectored, single sided $28,50 Head cleaning kit $28.00 TEI MAINFRAMES, S-100 MCS112 . . .$ 620, MCS 122 . . .$ 745. RM 12 $ 655. RM 22 S 790. OEM & Qty. discounts offered TARBELL Z80 CPU $395. New I/O card 4S + 2P $347. Double Density Controller . $435. CENTRAL DATA MULTIBUS: Z8000 $940. PMMI S-100 Modem $385. Compatible w/telex & Twx. 51 to 600 baud. On board pulse dialer. HAZELTINE 1500 $ 885. 1510 $ 980. 1520 $1,210. ESPRIT $ 695. 1 yr. on-site service contract! . . . .$ 49. TELETYPE Model 4320 AAK $1,140. Model 43ASR, 8 level, 1" tape . . ,$2,595. dBASE II demo package $75. MICROANGELO Price Lowered SUBSYSTEM W/ LIGHT PEN $2,300. Includes S-100 graphic card, 15" moni- tor, detached keyboard, light pen. Without light pen .$1,930. Graphics card alone $ 975. Screenware Pak II $ 350. TEKEM: Tektronix emulator ... $ 350. Color systems from 4 to 256 colors, Basic color system (4 colors) $2,330. IDS PRISM COLOR PRINTER . $1,795. Enhanced 560 w/software selectable colors; high speed printing at 200cps. CORVUS: New Lower Prices! 6.7MB . . $3,005. 11.3MB . . $4,655. 20.5MB $5,595. For S-100 and most other systems. EMULATOR Z80/8086. Will permit an 8086 using 86-DOS or CP/M-86® to run CP/M® programs w/ no modification $150, FORMULA: ALL-IN-ONE information manager+data base + w/p 4- accounting software. $595. KONAN SMC-100 hard disk controller. S-100, 2400MB control $1,469. Complete KONAN line available COMMUNICATIONS SOFTWARE Enables communications from a micro to a terminal or to another micro, mini or maxi computer. Source code $500. MICROSOFT COBOL-80 $560. BASIC-80 (interpreter) $270. BASIC COMPILER: $305. FORTRAN-80 $380. X-MACRO-86: $275. muLISP/muSIMP: $190. MICROPRO WORDSTAR: $320. MAIL MERGE: $110. QUICKSCREEN $149. Use CRT as scratch pad, produce quality screens, create reports & forms. Complete software $595. WE EXPORT Overseas Callers: \ VVX 710 588 2844 Phone 212 448 blW or C able OVVI NSA^M M JOHN D. OWENS Associates, Inc SEF OUR AD ON FACING PAGE April 1982 © BYTE Publications Inc 199 MKjPP".^' 1^ ]^^]dnf:li leliabili .1 i : It i §f > :., * m ... . , ' ■ ; : ~- V «** % \ Gsss^J -icturea: compuPro System E MPX Quality CPU 808618087 Since its introduction in early 1980, CPU 8085/88 — the first board to combine 8 and 16 bit processing — has become an industry standard. No other single board lets you run today's 8 bit software on an 8085 CPU, and tomorrow's 16 bit software on the popular 8088 CPU. Now CPU 8086/87 delivers ultra-efficient 16 bit operation, with 8 MHz* clock speeds (10 MHz* CSC). This ground-breaking CPU board teams Inters 8086 16 bit processor with sockets for their 8087 math co-processor (adds number-crunching capability rivalling many minicomputers), and the 80130. CPU 8086/87 is compatible with all 8 bit IEEE 696/S-100 memory and peripherals, as well as with more efficient 16 bit memories. There's even an optional 8 bit CPU board available for use with this, or any other, CompuPro 16 bit processor to preserve 8 bit software compatibility. CompuPro products stand out above the crowd. For business, scientific, and industrial solutions contact your CompuPro Systems Center. omouPro CPU 8086/87: $695, CSC $850. With 8087: price upon request. CPU 8085/88: $425, CSC $525. *8086 alone; 8087 requires lower clock rates CompuPro division Godbout Electronics, Oakland Airport, CA 94614-0355 (415) 562-0636 Circle 457 on inquiry card. GENERAL DATA BYTE INTERFACE TRANSFER DATA MANAGEMENT CONTROL BUS ^v DEVICE A ABLE TO TALK, LISTEN, AND CONTROL (e.g., COMPUTER) t jl DEVICE B ABLE TO TALK AND LISTEN (e.g., MULTIMETER) c DEVICE C ONLY ABLE TO LISTEN (e.g., SIGNAL GENERATOR) =^ DEVICE D ONLY ABLE TO TALK (e.g., COUNTER) o IFC ATN SRQ REN EOI DAV NRFD NDAC DiO (1-8) Figure 8: Sample configuration of the IEEE-488-1978 interface bus. Devices on the bus can be talkers, listeners, or controllers. Controllers manage the bus, activating and deactivating listeners. Talkers place data on the bus. Listeners accept data from the bus. A device connected to the bus can be a talker, a listener, a controller, or any combina- tion of the three. Most computers, like device A, are talker, listener, and controller so that the computer can configure the bus, then send and receive information. Device B, a multimeter, can talk and listen, sending readings and receiving set-up information such as range and function. Device C, a signal generator, listens only. Printers are usually listeners. Device D, a frequency counter, talks only, placing readings on the bus. The IEEE-488-1978 bus is divided into three sets of signals. The data bus carries the informa- tion being transferred. Data byte transfer control lines sequence the flow of informa- tion. The general interface management lines have special functions: IFC (interface clear) resets the bus interfaces; ATN (attention) sends bus commands; and SRQ (service request) signals bus interrupts. lines form the third group of signal lines: the general interface manage- ment group. These lines carry control and status information about the devices connected to the bus. Assigning Roles Figure 8 shows 4 devices attached to the HPIB. Device A has the talker, listener, and controller attributes. As a controller, device A may assign the 202 April 1982 © BYTE Publications Inc role of active talker to any device on the bus capable of undertaking that role, including itself. As a talker, device A can supply information to other devices on the bus. As a listener, device A can accept informa- tion from the other talkers on the bus. A computer is likely to have all three attributes. Although device A is the only con- troller shown in figure 8, more than one controller is allowed in an HPIB system. To prevent conflicts, however, only one controller can be active at a time. Control may be passed from one controller to another by means of a sequence defined in the standard. A controller designated the system controller becomes the active controller when the system is turned on. All other controllers must remain passive until control is passed to them. Device B in figure 8 is both a talker and a listener. It can be addressed by the controller and made an active talker or listener. An active talker controls the DAV signal line in the data byte transfer control group. An active listener controls the NRFD and NDAC signal lines. Device C can only be a listener. Device D is limited to being a talker. Either of these devices may be made active by the controller. A data trans- action is controlled by both the active talker and the active listener. The talker drives the bus with data, while the listener accepts the information transmitted by the talker. To avoid conflict, only one talker can be active at a time. However, several listeners can be active at once. Transferring Information The possibility of several active lis- teners receiving data simultaneously presents a problem because those listeners may not accept data at the same rate. Data-transfer speed must be paced by the slowest active listener, or that listener may lose data. The data transfer rate on the HPIB is controlled by an electronic voting system called the open collector. This voting system requires unanimous agreement among active listeners and the active talker before the data trans- action is completed. Information transfer takes place as follows: 1. All active listeners indicate on the NRFD line their state of readiness to accept a new piece of informa- tion. This signal line is usually con- nected to +5 V through a resistor. If an active listener is not ready, it pulls the NRFD line down to V by turning on a transistor con- Before you C.ITOH, see us When you see us we'll tell you about the line of quality printers available from C.ltoh, one of the largest manufacturers of computer peripherals in the world. C.ltoh has a printer to fit your needs. C.ITOH STARWRITER C.ltoh's line of letter-quality Daisy Wheel Printers offers an unmatched combination of price and performance. Since the Starwriter is available in two versions — the 25 cps Starwriter I and the 45 cps Starwriter II — you don't have to buy more printer than you need. If you don't need high print speed, the Starwriter I offers you more for your printer dollar. The Star- writer prints up to 136 columns of sharp letter-quality printing using cloth or film ribbons; its Automatic Bi-Directional prin- ting mode assures the highest possible throughput. The Starwriter uses industry- standard 96-character print wheels and ribbons, so there are no supply problems to worry about. Plug compatible with all major daisy wheel printers, it re- quires no changes in software or hardware and is available with a Centronics Parallel or RS 232C Serial interface. Optional Accessories: Bi-Directional trac- tor, Single Sheet Feeder. The Starwriter is backed by C.ltoh's one-year warranty (90 days parts and labor, 9 suc- ceeding months parts). STARWRITER I Parallel 25 cps. .1440.00 STARWRITER I Serial 25 cps ... . 1540.00 STARWRITER II Parallel 45 cps. 1770.00 STARWRITER II Serial 40 cps. . .1795.00 Bi-Directional Tractor 239.00 Single Sheet Feeder . . .1395.00 Circle 19 on inquiry card. C.ITOH PRO/WRITER The C.ltoh Pro/Writer offers professional quality at a very low price. Compare the advanced features that are standard on the Pro/Writer with what other printers in its price range offer, and you'll find that none offer so much value for the money; you won't have to buy 'op- tions' to get the performance you want. The Pro/Writer uses the latest in dot-matrix printing technology to provide a productive cost-effective solution to all your printer needs. Some of the Pro/Writer's Advanced Features: N x 9 MATRIX BI-DIRECTIONAL PRINTING PROPORTIONAL SPACING DOT ADDRESSABLE GRAPHICS SPECIAL GRAPHICS CHARACTERS ENHANCED PRINTING FRICTION & TRACTOR FEED PRO/WRITER Centronics Parallel PRO/WRITER RS 232C Serial 100 CPS PRINT SPEED LOGIC SEEKING PICAS (10 PITCH) & ELITE (12 PITCH) 5 ALPHABETS 8 TOTAL CHARACTER FONTS DOUBLE-WIDTH PRINTING OPTIONAL RS 232C W/ X-ON & X-OFF 549.00 .599.00 We built a reputation on our prices and your satisfaction We guarantee everything for 30 days. If anything is wrong, return the item and we'll make it right. And, of course, we'll pay the shipping charges. We accept Visa and Master Card on all orders; COD orders, up to $300.00. Add $2.00 for standard UPS shipping and handling on orders under 50 lbs. delivered in con tinental U.S. Call for shipping charges over 50 lbs. Foreign, FP0 and AP0 orders, add 15% for shipping. Californiana add 6% sales tax. Prices quoted are for stock on hand and are subject to change without notice IPUTER PRODUCTS lb order, or for information, call: (213)706 31245 LA BAYA DRIVE, WESTLAKE VILLAGE, CALIFORNIA 9136: Basic Betting is your basic guide to winning! If you understand BASIC pro- gramming and enjoy a sporting wager, this new paperback can help you turn your fun into profit. Drawing on years of experience with both computers and gam- bling, James Jasper, a profession- al computer consultant, gives you • Actual, tested programs- complete and ready to run — for picking winners in horse- racing, football, baseball, and basketball. • A wealth of professional tips, like the mistake (in your favor!) often made in calculating basketball odds. • Sources for your data bases, including descriptions and addresses. • Instructions for developing new programs for your favorite sport! Even if your winnings are all imaginary, you'll discover new dimensions in sports and new pleasure in using your computer. Look for BASIC Betting at book- stores, or use the coupon to order direct. Please return the coupon to: b " 4t ^ ST. MARTINS PRESS 175 Fifth Avenue, New York, N.Y 10010 Attn: JW Please send me copy(ies) of BASIC Betting at $10.95 delivered. My check or m.o. is enclosed in the amount of $ I may examine it for thirty days and, if not 100% satisfied, I can return it for a complete refund. City_ _Z.p_ DATA LINES FALSE DAV NRFD NDAC TRUE Figure 9: Diagram of timing on the IEEE-488-1978 bus. Data transfers occur with a unique 3-wire handshake. First, the active talker waits for all active listeners to release the NRFD (not ready for data) line. When this happens, the signal rises to a positive level. The talker then places the data on the data lines, waits 2 microseconds, and drives the DAV (data valid) line low, indicating that the data should now be accepted. Recognizing the transition in the DAV line, the active listeners drive NRFD low. The active listeners have as much time as necessary to release NDAC (not data accepted). When all active listeners do release NDAC, its voltage rises to a positive level. This tells the talker to release DAV. At the release of DAV, the listeners pull NDAC low again. This restores the bus to the original state, where it is ready for another transfer. nected to the signal line. The ac- tivated transistor acts as a short to ground, pulling the voltage on the NRFD line to ground potential or V. When the listener is ready to accept data, it turns off this tran- sistor. When all active listeners turn off their transistors, the resistor connected to +5 V pulls the NRFD signal line up to around + 5 V. The active talker observes the state of the NRFD line and will not start the data transfer until the signal line reaches a high voltage level. 2. The active talker observes that the NRFD line has gone high. It places a data byte on the data lines and waits 2 microseconds (0.000002 seconds). It then asserts DAV by pulling it low to V. This 2-microsecond wait, called settling time, allows the data to reach valid logic levels on the data lines. The assertion of DAV is a signal to the active listener(s) to read the infor- mation on the data bus. The listeners acknowledge the assertion of DAV by immediately pulling back down on NRFD. 3. Until now, the active listeners have held NDAC low. When DAV is asserted and all of the active listeners accept the data on the data lines, they will release NDAC. As the slowest active listener releases NDAC, the pullup resistor will cause the signal line to go high. 4. The active talker observes the NDAC line in a high state. It acknowledges the listeners' accep- tance of the data by releasing DAV. The release of DAV signals the listeners that the data transfer is complete; they again pull NDAC low in preparation for the next transfer. Figure 9 shows a timing diagram of the complete handshake. Note that control of the data transfer is effected by the active talkers and listener(s). Once the controller has configured the bus, it takes no part in subsequent 204 April 1982 © BYTE Publications Inc W hitesmiths, Ltd . — is now shipping Pascal Compilers for 10 (count em ten) different operating system families: RSX11M, RSTS/E, IAS ldris/R11, UNIX/V6, UNIX/V7 UNIX/32V* 'Available in source form only. Idris is a trademark of Whitesmiths, Ltd. ■ UNIX is a trademark of Bell Laboratories ■ CP/M is a tradematk oi Digital Research l RT-1 1 , and VMS are trademarks of Digital Equipment Corporation ■ VERSAdos is a trademark of Motorola Inc. RSX-11M, RSTS/E, All implementations support the full ISO Pascal (Level 0). All pass the Tasmanian Validation Suite with flying colors. And all are free of those tempting non-standard extensions-because we added the only extension you need. Separate Compilation. You can partition your Pascal program into separately maintainable files. You can write library functions to add to the extensive set we give you (about 100 of them). And you can mix in modules written in other languages, like assembler (if you must) or C (to preserve portability). In fact, C language support comes with every Pascal Compiler we sell. Our native Pascal Compilers are only $950, including shipping in the con- tinental U.S. Cross Compilers, for most combinations of host system and target machine, $1350. Interested? Write or call. Distributors: Australia, Fawnray Pty Ltd., Brighton-Le-Sands 522 5574 Japan, Advance Industries, Chiyoda-ku, Tokyo 03-258-0839 United Kingdom, Real Time Systems, Newcastle upon Tyne 0632 733131 'Whitesmiths, Ltd" P.O. Box 1132 Ansonia Station New York, N.Y. 10023 (212) 799-1200 Telex 645 592 Bit* \ Information Type 7 6 5 4 3 2 1 Bus command X c C C C c Listen Address X 1 L L L L L Talk Address X 1 T T T T T Secondary Address X 1 1 S S S S S Table 1: Interface definitions for the 98032A parallel interface. Table la defines the input registers, and table lb defines the output registers. transactions until reconfiguration is desired. Configuring It Out Now that data transfer on the HPIB has been covered, let's consider how the bus is configured. One of the general interface management lines is called ATN (attention). The active controller manages this line. ATN signifies whether the data transfers on the bus are data or control informa- tion. The active talker controls data transactions, as explained above, but the active controller supervises con- trol transfers. When the controller wishes to con- figure the HPIB, it asserts the ATN line. This causes any active talker to relinquish control of the DAV line. Transmission of control information occurs in the same manner as transfer of data. The difference is that when ATN is asserted, the active controller takes the place of the active talker, and both talkers and listeners accept the information. All devices, whether active or not, accept information transmitted by the controller when ATN is asserted. The active talker and active listeners may be designated during the transmission of control informa- tion. The data lines carry control in- formation after ATN has been asserted. Table 3 lists the meanings of the control data bits. Note that bit 7 is not used. Bits 6 and 5 serve to classify the control in- formation as to command type. A control transfer with bits 6 and 5 set to is a bus command that directly controls devices on the bus. Trigger- ing a function and passing control from the active listener to a passive one are two examples of bus commands. Transmission of a control byte with bit 6 set to and bit 5 to 1 ac- tivates a listener. A listener that observes its address in the lower 5 bits of a listen address control byte becomes active. When ATN is negated, it will assume control of NDAC and NRFD. Listeners that R 2 l/0 S-100 ROM, RAM & I/O BOARD Building Blocks for Microcomputer Systems, Dedicated Controllers and Test Equipment. ECT's R 2 l/0 is an S-100 Bus I/O Board with 3 Serial I/O Ports (UART's), 1 Parallel I/O Port, 4 Status Ports, 2K of ROM with the 8080 Apple Monitor Program and 2K of Static RAM. $295.00 RM-10 S-100 RACK MOUNT CARD CAGE ECT's RM-10 is a rack mount 10 slot Card Cage with Power Supply, consisting of an ECT-100 rack mount Card Cage (19"W x 12,25"H x 8"D), the MB-10 Mother Board (with ground plane and termination) all 10 connectors and guides and the PS-15A Power Supply (15A@8V,1.5A@±16V). $295.00 Specializing in Quality Microcomputer Hardware Industrial • Educational • Small Business • Personal Card Cages, Power Supplies, Mainframes, CPU's, Memory, IIO, OEM Variations ELECTRONIC CONTROL TECHN0L06Y (201) 686-8080 763 Ramsey Ave., Hillside, NJ 07205 206 April 19fl 2 © BYTE Publications Inc Circle 166 on inquiry card. EIKOSHA , , ' " GP-100A: US$389 COMMAND PERFORMANCE. Seikosha gives you all the best features— including economy and super-clear graphics. Unlike some graphic printers, Seikosha's new GP-100A (Jni-Hammer Graphic Printer puts full dot addressable graphic at your command. The GP-100A lets you repeat a column of data as many times as needed with just one command. Software control enables double-width character output, and the positioning is both character and dot addressable. Designed for simple operation, it ranks among the most cost-efficient graphic printers on the market. Command performance tech- nology that not only works for you now, but takes you well into the future. Other valuable features: •Graphics, regular and double width character modes can be intermixed on the same line. •Automatic printing. When the text exceeds the maximum line length, there is no loss of data due to overflow. • Self-test printing is a standard feature. •Centronics type parallel interface. • Paper width is adjustable up to 10 inches. • Optional Interface: RS232C, IEEE488, apple II, etc. Graphic Printer ,RJ*2 8»rie« Distributed by AXIOM CORPORATION 1014 Griswold Avenue San Fernando, Calif. 91340 Phone (213) 365-9521 TWX (910) 496-1746 Manufactured by SEIKOSHA SYSTEM EQUIPMENT DIV. 4-1-1 Taihei Sumlda-ku ToRyo Japan. Phone: 03-623-8111 Telex: 262-2620 Circle 368 ( nquiry card. don't observe their listen addresses in a control transfer don't change state, remaining as they were before the controller asserted ATN. Deactivating Listeners The HPIB provides a way to deac- tivate all active listeners. The 5 bits of the listen address allow 32 listen ad- dresses. These addresses range from to 31. Address 31 is the "unlisten" ad- dress. Active listeners observing the unlisten address in a listen command's address field will go inac- tive. The definition of talk addresses is similar to that for listen ad- dresses — with one exception: any ac- tive talker that observes a talk com- mand to another device will go inac- tive. As a result, activating one talker guarantees deactivation of any other active talkers. This prevents conflicts on the bus. Talk-address 31 is the "untalk" address. When the con- troller issues an untalk command, no active talkers are left on the bus. Secondary addresses are used to address subunits within a device. Some HPIB instruments are actually clusters of devices, but secondary ad- dressing allows addressing of a device within such a cluster. The remaining four lines in the general interface-management group serve to control the interface sections of the HPIB devices. IFC (interface clear) may be called on by the active controller to override all bus activity and to place the bus in a known state. This signal aborts any data transfers in progress and is used only when something has gone wrong. The REN (remote enable) signal allows the HPIB to control a device. The active controller uses the REN line to indicate to an active listener whether or not the listener will use the information sent to it by a talker. EOI (end or identify) is applied in two ways. First, the active talker may assert it to designate a data byte as the last in a message. EOI is also part of a serial poll, which will be dis- cussed later. The SRQ (service request) signal enables a device to get the active con- troller's attention. This signal is a re- quest, not a demand. The controller may ignore SRQ as long as it wishes. When the controller finally does acknowledge SRQ, it has to deter- mine which device is requesting ser- vice. Since SRQ is shared by all devices on the bus, the requester isn't identified immediately. Polling Along A controller can employ two methods to determine the address of the device requesting service. Both methods are called polls, A poll is the controller's request for status infor- mation. The controller may request the status of any device individually by addressing the device as a talker and sending that device a serial-poll enable command. This constitutes one of the bus commands a controller Once the controller has configured the bus, it takes no part in subsequent transactions until reconfiguration is desired. can send when it asserts ATN. Using the serial poll, the controller can ob- tain 8 bits of status information from the addressed device. The controller then sends a serial-poll disable com- mand to the device, returning it to data mode. Serial polling's advantage lies in the fact that 8 bits of poll information are obtained from each device polled. One bit can be used to indicate whether or not the device is re- questing service. The remaining 7 bits are available for other purposes. A disadvantage of the serial poll is speed. Each device on the bus must be polled in turn, since more than one device may be requesting service. A faster method of polling is the parallel poll, The parallel poll is per- formed when the active controller asserts both ATN and EOI. Up to 8 devices may respond, each on a dif- ferent data line. The only information obtained in a parallel poll is whether or not a device is requesting service. Since each device has only 1 bit to respond with, obtaining further infor- mation is impossible. You Don't Have to Know One of the IEEE-488 standard's best features is that a system user doesn't have to know any of the information presented in this article. The stan- dard, if followed by all the manufac- turers of the devices put on a bus, guarantees that devices can talk to each other. This assumes that the system builder doesn't violate the standard by placing two devices at the same address, or by connecting two system controllers to the bus. What then does the system user need to know? The standard does not specify the messages and data for- mats, both of which depend on the application. For example, if a voltmeter wants to tell the computer that it detects +1.234 volts at its in- put, what does it send to the com- puter as data? Most computers and computer languages prefer ASCII characters. HPIB specifies that ASCII is to be used. Next, the data format must be determined. Will the digits be sent most significant or least signifi- cant first? Again, most computers and languages prefer the digits just as you might type them, from most significant to least. Thus, the voltmeter might send the following sequence of characters: + 1.234 The and characters stand for carriage return and linefeed. These characters are often used as message terminators in computer communications. alone is usually sufficient. The definition of messages and message formats leaves the IEEE-488 standard and enters the realm of HPIB. This higher-level implementa- tion removes yet another layer of in- terface problems from the shoulders of the system user. Next month, I'll discuss two other major types of interface: the BCD in- terface, often used when a computer receives data from scientific in- struments, and the serial interface, used to transmit data over a single wire. We'll see how each evolved to deal with specific problems in com- munications. ■ 208 April 1982 © BYTE Publications Inc Circle 409 on inquiry card. •lliJMIJ[efilJMiIU:lJ FROM TELEVIDEO: THE SMART 910 PLUS ■ ^^^m Our new ideas have a way of sweep- ing the market. In just a few years, TeleVideo has come from nowhere to become the No. 1 independent in CRT terminals. The reason: we offer exceptional quality reliability and usability at a price no one can beat. (In fact, we use the same high quality modules, from keyboards to monitors, throughout the entire line.) The smart 910 Plus Block Mode terminal is our latest innovation. For the money you'll find nothing that outperforms it. For example, simply by touching a key you can activate its gated printer port. Another point: since service is a major concern, we have ours handled nationwide by one of the best: General Electric s Instrumentation and Communication Equipment Service Centers. Right now, we have the new 910 Plus ready for immediate delivery To order or have questions answered call 800-538-8725 (toll-free outside California.) Since it's priced at just $699 per unit, your decision should be very easy tflfekMdeo TeleVideo Systems, Inc. 1170 Morse Avenue, Sunnyvale, CA 94086 800-538-8725 (toll-free outside California) 910 Pius Features • Block mode • Off-line editing • 10 programmed function codes • Changeable codes • Protected fields • 5 screen attributes (blink, blank, reverse, underline, half intensity) • 15 baud rates (50b to 10.2Kb) • Gated printer port • Typewriter-style keyboard • Typewriter tabs • Erase to end line • Erase to end of page • Self-test • Monitor mode • 4 strappable languages JFORN1A Santa Ana 714/557-6095; Sunnyvale 408/745-7760 • GEORGIA Atlanta 404/255-9338 • TEXAS Dallas 214/980-9978 • ILLINOIS Chicago Area 312/351-9350 MASSACHUSETTS Boston 617/668-6891 • NEW YORK/NEW JERSEY 201/267-8805 • UNITED KINGDOM West End Surrey 44-9905-6464 ATARI HOME COMPUTERS Texas Instruments ■(*Uiia^_ A ATARI ATARI 800 16K . . . $679 32K... $749 48K... $819 410 Recorder $76.00 810 Disc Drive $449.00 822 Printer $269.00 825 Printer $629.00 830 Modem $159.00 820 Printer $269.00 850 Interface $169.00 New DOS 2 System $29.00 PACKAGES 481 Entertainer $83.00 482 Educator $130.00 483 Programmer $57.00 484 Communicator $344.00 ATARI HOME COMPUTER PROGRAMS Home Office CX404 ATARI Word Processor $1 19.00 CX8102 Calculator $29.00 CX412 Dow Jones Investment Evaluator $99.00 CX4109 Graph It, Joystick optional $17.00 CX4104 Mailing List $20.00 CX4115 Mortgage & Loan Analysis $13.00 CX406 Personal Financial Management System . . . $59.00 CX4103 Statistics 1 $20.00 CX8107 Stock Analysis $20.00 CXL401 5 TeleLink 1 $23.00 Home Study CX4101 An Invitation to Programming 1 $20 00 CX4106 An Invitation to Programming 2 $23.00 CX4107 Biorhythm $13.00 Conversational Languages (ea.) $46.00 CX4121 Energy Czar $13.00 CX41 14 European Countries & Capitals $13.00 CX4108 Hangman, Joystick optional $13.00 CX4102 Kingdom $13.00 CXL4007 Music Composer $47.00 CX4123 Scram, uses joystick $20.00 CX41 12 States & Capitals $13.00 CX41 10 Touch Typing $20.00 Home Entertainment CXL4013 Asteroids $35.00 CXL4004 Basketball • $27,00 CX4105 Blackjack $13.00 UXL4009 Computer Chess $33.00 CXL4012 Missile Command $35.00 CXL4008 Space Invaders $35.00 CXL401 1 Star Raiders $42.00 CXL4006 Super Breakout $33.00 CXL4010 3-D Tic-Tac-Toe $27.00 CXL4005 Video Easel $24.00 Programming Languages and Aids CXL4003 Assembler Editor $47.00 CXL4002 ATARI BASIC $47.00 CX8126 ATARI Microsoft BASIC $70.00 CXL4018 PILOT $72.00 CX405 PILOT $105.00 ATARI 400 16K.... $329 32K. . . . $478 48K. . . . $555 CX30 Paddle $18.00 CX40 Joy Stick $18.00 CX853 16K RAM $89.00 Microtek 16K RAM $75.00 Microtek 32K RAM $159.00 Ramdisk (128K) $539.00 One year extended warranty $50.00 THIRD PARTY PROGRAMS ATARI Program Exchange: Eastern Front '41 $25.50 Avalanche .- $15.50 Outlaw $15.50 747 Landing Simulation $15.50 Babel $15.50 Dog Daze $15.50 Downhill $15.50 Attack! $15.50 Blackjack-Casino $15.50 Reversi II $15.50 Domination $15.50 Solitare $15.50 Disk Fixer $15.50 Supersort $15.50 Data Management $15.50 Chameleon $15.50 Instedit $15.50 Insomnia $15.50 My FirstAlphabet $25.50 Mapware $18.00 Number Blast , $1 1 .50 Family Cash Flow $15.50 Weekly Planner $15.50 Bowler's Data Base $13.00 Banner Generator $1 1.50 Visicalc "' $169.00 Letterperfect (Word Processor) $109.00 Ricochet $14.50 Crush Crumble & Chomp (cassette or disk) $24.00 Star Warrior {cassette or disk) $29.00 Rescue at Rioel (cassette or disk) $24.00 Datestones (cassette or disk) $16.00 Invasion Orion (cassette or disk) $18.50 Mission Asteriod $22.00 MouskATTACK $31.00 The Next Step - $34.00 Softporn $27.00 Wizzard & Princess $29.00 K-BYTE Krazy Shoot Out (ROM) $39.00 Protector (Disk 32K) $32.00 Jaw Breaker (on line disk) $27.00 Ghost Hunter (cassette) $24.00 Ghost Hunter (disk) $30.00 COMING SOON PAC MAN (May) $35, CENTIPEDE (June) $35 CAVERNS OF MARS (April) $32 TI-99/4A $ 359 PHP 1600 Telephone Coupler $179.00 PHP 1 700 RS 232 Accessories interface $179.00 PHP 1800 Disk Drive Controller $239 00 PHP 1L50 Disk Memory Drive $389 00 PHP 2200 Memory Expansion (32K RAM) $319 00 PHA 2100 R F Modulator $43 00 PHP 1100 Wired Remote ControiiersiPam $31 00 32K Expansion $329 00 PHP Printer Solid State $319 00 PHM 3006 Home Financial Decisions $26.00 PHM 3013 Personal Record Keeping $43.00 PHD 5001 Mailing List $60 00 PHD 5021 Checkbook Manager $1800 PHM 3008 Video Chess $60 00 PHM 3010 Physical Fitness $26 00 PHM 3009 Football $26 00 PHM 3018 Video Games I $26 00 PHM 3024 Indoor Soccer . $26 00 PHM 3025 Mind Challengers $22 00 PHM 3031 The Attack $35.00 PHM 3032 Blasto $22 00 PHM 3033 Blackjack and Poker $22 00 PHM 3034 Hustle , $22.00 PHM.3036 Zero Zap $18.00 PHM 3037 Hangman $18 00 PHM 3038 Connect Four $18 0Q PHM 3039 Yahtzee $22 00 PRINTERS Centronics 739-3 $619.00 Centronics 739-1 $519.00 Diablo 630 Special $1799 00 Epson MX70 $359.00 MX80 $469,00 MX80FT Call MX100 Call NEC 8023 $549.00 7730 Call 7720 Call 7710 , ■ ■ Call Okidata 82A $499.00 83A $769.00 84 $1129.00 Citoh Starwriter F10-40 CPS $1469.00 F10-55CPS Call Paper Tiger 445G , $699 00 460G $899.00 560G . , $1129.00 Talley 8024-7 $1399 00 8024. L $1629 00 HOW TO ORDER: Phone orders invited or send check or money order and receive free shipping m the continental United States. PA and NEV. add sales tax, computer mail order west Franco Hables Espanol 800- 648-335I IN NEVADA, CALL (702) 588-5654 P.O. BOX 6689, STATE LINE, NEVADA 89449 210 BYTE April 1982 Circle 108 on inquiry card. HEWLETT PACKARD HP»85 s 1999 80 Column Printer $799.00 HP- 125 $1999,00 HP-83 $1699.00 HP«85 16K Memory Module $169.00 5 1 « " Dual Master Disc Drive $1929.00 Graphics Plotter (7225B) $2079.00 NEW 1 HP»87 $1999.00 Hard Disk w/Floppy $4349.00 Hard Disk $3440.00 "Sweet Lips" Plotter $1 149.00 HP41CV Calculator $259 41 C 11 c 12C 34 C 38C HP-41 Printer HPIL CALCULATOR PERIPHERALS IL Modual Digital Cassette Printer/Plotter Card Reader ... ... Optical Wand CALL FOR SOFTWARE INFORMATION $189.00 $119.00 $129 00 $117.00 $119.00 $340.00 $104.00 . $449.00 . $419.00 $164.00 $99.00 XEROX & Xerox 820 System I 5 % " $2450.00 System II 8" $2950.00 CPM $%" $169.00 Word Processing $429.00 Super Calc $269 00 CALL FOR MORE INFORMATION Ql commodore BUSINESS MACHINES CBM 8032 M069 SOFTWARE Word Pro 5 Plus $319.00 WordPro3 Plus $199.00 WordPro4 Plus $299.00 Commodore Tax Package $589.00 Visicalc $169.00 Medical Billing $449.00 The Source $89.00 OZ2 Information System $289,00 Dow Jones Portfolio $129.00 Pascal $239 00 Legal Time Accounting $449.00 Word Craft 80 $289.00 Power , $79.00 Socket-2-Me $20.00 Jinsam $Call MAGIS $ Call The Manager $209.00 Softrom $129.00 Real Estate Package $799.00 BPI Inventory Control $319 00 BPI Job Costing $319.00 BPI Payroll $319.00 BPI General Ledqer $329 00 Creative I SAM $79.00 Creative General Ledger $229.00 Creative Accounts Receivable $229.00 Creative Inventory $229.00 4032 $969 00 4016 $769 00 8096 Upgrade Kit $399 00 Super Pet ... $1599.00 2031 $529.00 8050 $1299 00 404 $969 00 8300 (Letter Quality) $1799.00 8023 $769 00 4022 $59900 Petto IEEE Cable $37 00 IEEE to IEEE Cable ... $46TJ0 Tractor Feed for 8300 ... $240.00 8010 Modem $229 00 'Vic 6 Pack Program VIC1530 Commodore Datassette VtC'l540 Disk Dnve VIC1515 VIC Graphic Pnnter VIC1210 3K Memory Expander VICH 108K Memory Expander VIC1011 RS232C Terminal Interlace ViC 1 1 12 VIC IEEE 488 Interface VIC 1 2 1 1 VIC 20 Super Expander VT232 VlCTerm I Terminal Emulator $44 00 $69 00 $499 00 $339 00 $32 00 $53 00 $4 3 00 $86 00 $53 00 $9 00 VIC 20 $259 COMPLETE VIC1212 Programmers Aid Cartridge VIC1213 VICMON Machine Language Monitor VIC1901 VIC AVENGERS VIC1904 SUPERSLOT VIC1906 SUPER ALIEN VIC1907 SUPER LANDER VIC1908 DRAW POKER VIC1909 MIDNIGHT DRIVE VT106A Recreation Pack A VT107A Heme Calculation Pack A VT164 Programmable Character'Grameqraphics New VIC Software Household Finance $27.00 Terminal VIC Games $19 00 Un Word VIC Home Inventory $13.00 Grafix Menagerie . VICRec/Edll $13 00 VIC PICS VL101 Introduction to Computing $19.00 Ticker Tape VL102 Introduction to BASIC Programming $19.00 Banner Headlmer . VM110 VIC 20 Programmers Reference Guide . $15.00 rs 232 $45 00 $45 00 $23 00 $23 00 $19 00 $23 00 $23 00 $23 00 $44 00 $44 00 $1200 $13.00 $13 00 $11 00 $15 00 $13.00 $1300 $39.00 Modems Novation Auto $239 00 D Cat $169 00 Cat $159 00 Hayes Smart $239.00 Livermore Star $1 19.00 Terminals Televideo 910 91 2C 920C 950 Call for computers Zenith 219 Adds $579 00 $699.00 $749 00 . $939 00 $749 00 $54900 Monitors Amdex 12" B&W 12" Green 13" Color Sanyo 12" B&W 12" Green 13" Color . Tl 10" Color $139.00 $14900 $349 00 $25900 $26900 $449 00 $349 00 Above are cash prices, add 3% for Master Card and Visa purchases computer mail order 800-233-8950 IN PA. CALL (71 7) 327-9575 477 E. THIRD ST., WILLIAMSPORT, PA 17701 Patricio Hables Espanol Circle 108 on inquiry card, BYTE April 1982 211 1LLL The Osborne 1, Zeke's New Friends, and Spelling Revisited A seasoned computer user looks at new products and updates. Jerry Pournelle c/o BYTE Publications POB 372 Hancock, NH 03449 "It's the great software drought/' said my mad friend Mac Lean. "Have you noticed? There's no good new software. Just updates and revisions and new versions of old programs." "Not true/' I protested. "Just yesterday I got Sorcim's Supercalc." "Sure. The CP/M version of a year-old Apple program. Good stuff. Useful. Excellent. But not new." "Hmm. Maybe you're right. Well, at least they're improving old pro- grams. I have an update for Spell- guard." "Aha/' said my mad friend. "Tell me, are you still using Spellguard?" "Yep." "Thought you had a whole mess of new spelling programs." "I do. Here's one of them." I held up Microproof . "But I don't use them. Better to stay with Spellguard. Espe- cially now, with its improved dic- tionary." Which is true. I suppose it comes as no surprise that I am very interested in spelling and editing programs. After all, words are my business . . 1 need good spelling programs. After all, words are my business, and I am, according to Robert Heinlein, one of the "wurst spellurs" he has ever encountered. I need good spell- ing programs, and I have to use them a lot, which means I'm interested in speed and convenience, which is why I stick with Spellguard despite its lack of certain features. Example: in my previous Spell- guard review [see November 1981 BYTE, page 449], I said "it corrects spelling." BYTE's editors, in the in- terest of accuracy, changed that to "finds and marks spelling errors." Other programs, such as Microproof, correct spelling errors. All true, but irrelevant. The job to be performed is spelling correction, and Spellguard does that [also see "Five Spelling- Correction Programs for CP/M- Based Systems" by Phil Lemmons, November 1981 BYTE, page 434]. Example: Microproof 's specifica- tions make it sound far better than Spellguard. (Let me call them MP and SG from here on.) MP has a 50,000- word dictionary compared to SG's 20,000. MP knows about plurals and prefixes; you can tag a word as a noun or an adjective or an adverb, and MP will take the root and add suffixes and prefixes and such like. Finally, MP lets you correct the word and will then go off and put that 212 April 1982 © BYTE Publications Inc Circle 25 on inquiry card. word in your text file, while all SG does is mark it for you to go fix using your standard editor. Sounds great, doesn't it? The trouble comes when you use it. That's presuming you even try; the manual was enough to cause me to leave MP in the box for over a month. (Digression. The Microproof manual, which, according to its in- terior blurbs, was written by "an acknowledged expert in the field of programmed learning," is a general- purpose thing, intended for several versions of the program; and because it's never made clear what version you have, it's unutterably confusing. And that sort of thing happens all the time. TO ALL SOFTWARE PUBLISH- ERS: look, if you want to charge $100 and more for programs, you can darned well furnish a manual tailored for each program!) In Microproof's favor, I have to say that when you actually start using the program — as opposed to trying to figure out how to use it — it gets sim- ple. The prompts are clear and the procedures are simple. But it's slow. Ye gods, it's slow to work with. Instead of leaving the in- structions on the screen and using the same entry line over and over again, as SG does, MP clears the screen and rewrites it, prompts and instructions and all, for each word it didn't recognize — dozens of them. Eventual- ly you get through that, after which MP reads your text file and corrects it. That, however, takes about as long as it would have taken to load your editor, bring in the file, and search for the marked blocks; and because, if you're like me anyway, you'll want to see the corrected text and possibly reformat it before print- ing it and sending it out, you'll have to load the editor and text file anyway. Now about those prefix and suffix "features." I suspect they have some- thing to do with the fact that I CAN- NOT get Microproof to believe that "index," "kilobyte," "milestone," "undoubtedly," "Unix," and "auto- matic" are words. I went through my third "User's Column" (the one re- viewing Spellguard!) as a test file four times and each time I patiently entered those words into the MP dic- tionary; and next pass I got them read back to me as misspellings. (To make the test fair, I used Microproof on this text too, and not only won't it admit that the above are words after two passes, but until I entered it, it didn't recognize Micro- proof! Meaning, I would suppose, that they didn't use the program on their own manual. If they won't use it, why should anyone?) There's worse. MP doesn't know about apostrophes. It gives me the "weren" of "weren't" as a candidate word. It does the same with "doesn." And if you use dashes! Spellguard understands dashes and hyphens, but if you have a double hyphen (which represents a typeset dash) in your text, SP thinks that is two separate words and examines each. Micro- proof offers me the "program — as" and "it — it" that I used above as can- didate words. If you use many dashes in your text, you will, I assure you, go quite mad after about the third pass Microproof makes at your text. Finally, Microproof doesn't know much about error handling. It takes forever to go through a 6500-word text file; and if you've left insufficient space on your disk for the original file plus a backup (.BAK) file, then when Microproof finds that out, it simply dumps the job, leaving you either in CP/M or the monitor, depending on just how confused MP got. Either way, you've lost all the work you just did. So. Microproof is a heroic effort to make a more convenient spelling program. They tried to do right. The concept was good. The execution, though, leaves something to be de- sired. There's a version geared to work CALCULATOR EPROM MEMORY for Hewlett-Packard 41C/CV EPROM memory with custom keyboard overlay also produced by DDS. • Plugs into any port of the HP-41C or -41CV calculator. • Provides non-volatile program storage formatted and accessed as if it were a custom HP calculator ROM. • Uses standard 2716, 2732, and 2764 EPROMs (Eraseable Programmable Read Only Memory). • Holds calculator programs in 4K, 8K, or 16K segments. • Completely portable and requires no external power supply or battery. USES • Field testing of software before the ROM is manufactured. • Low volume production runs where a custom ROM would be prohibitively expensive. $299.95 DALLAS DEVELOPMENT SYSTEMS 7410 Stillwater Drive Garland, Texas 75042 [214] 238-1776 April 1982 © BYTE Publications Inc 213 User's Column. with either Electric Pencil or Scripsit for the TRS-80 Model I (and III) and TRSDOS. (Microproof has recently fixed most of the problems, partly because I sent a preliminary copy of this review to them. See next column for details; Microproof is now com- petitive with Spellguard.) Which, incidentally, has been great- ly improved. Now there's an explicit way to remove misspelled words er- roneously entered into the dictionary. Also, the updated version packs the dictionary into half the space and runs about twice as fast. It took me just about an hour, using Microproof, to shape up a 6500-word column; with new Spellguard, the whole job (in- cluding looking up and entering into the program's dictionary about 100 new words) took fewer than 20 minutes. The Spellguard documentation re- mains excellent, as clear and precise as anything I've seen in the field. Still highly recommended. Zeke's New Friends A few minutes ago, Arthur C. Clarke called me from Sri Lanka. (He lives there. I think the nation has de- clared him a national treasure; I know that when Robert Heinlein visited him, Dr. Clarke was able to arrange for a Sri Lanka air force helicopter to take Robert about the country.) Arthur had seen some of my com- puter articles, and what he wanted to know was what everyone, nowadays wants to know: what do you buy for a first computer? Unfortunately, the answer is, it depends. But let's look at the problem. It's not unrelated to a second difficul- ty, one I have myself. IMPORTS NEC8023A $495 Epson MX-80 $444 Okidoro82A $469 Epson MX-100 $719 OkidafQ 83A w/trac $749 Okidoto 64 J200 c.p.s,) $1059 HIGH SPEED DataSoufh DS-180 $1269 Anodex950l $1244 TI810 Basic $1359 Molibu 200 call IDS560G $1129 IDS Prism 80 $935 LETTER QUALITY Printmaster 40 c.p.s $1449 Printmaster 55 c.p.s. ..-.. $1649 NEC 3510 $1895 NEC 7710/7730 $2340 NEC 7720 $2695 e-MfcllliMI^ 153 NORTHSTAR TELEVIDEO We now pretest every Northsrar we sell and Th * n T e ~ SJSSSSSl ^%22l ° E £5 back them with our own fast warranty service. ' n <*t detachable ^keyboard. 7 50K formatted. New low Horizon price. dual f, °P^ s - 64K CP ' M ® °** more Five software business modules $695. Advantage call jelevideo 802 $2795 Horizon li 64K Quad $2895 Te u An , ^/ 4 niu^« u^ «„«. TSS ,, 6 y 4 f j 6 295 ' ' 9 " ' * 5395 ALTOS Our tech's favorite system - 0" floppy, hord disks, and multi-user under MP/M or Oosis. Coming soon - 16 bit systems. 8000-2 wCP/M . $2749 8000-10 w 10 Meg., 208K $6375 6000-15,12,14 call ZENITH The all-in-one that's backed by your local Zenith-Heoth Service center. Green Screen, CP/M®. Supercalc, and Dosic incl. Z-89w/48K $2135 2-90-82 w/64K $2395 XEROX 820 w/ Dual 5 1 /4" $2349 DYNABYTE Call \Jy / v Ltd. Scottsdale Systems 6700 E. McDowell Rood, Suite 1 i 0, Scottsdale, Arizona 85257 3C (602)941-5856 Coll 8-5 Mon.-Fri. (We Export) TWX 91 0-950-0082 (IMEC SCOT) QO J LOW COST Adds Viewpoint $544 Televideo9l0 $579 ADM3A $569 SoroclQl30 $589 . TELEVIDEO Televideo912 $699 Televideo920 $728 Te!evideo925 $775 Televideo950 ..... $927 TERMINALS AmpexDSO Dialogue 80 Amber Mime Act 5A Soroc IQ 120 $925 $969 $799 $729 Volker Croig 404 $599 SOFTWARE Wordstar D. Base li Mailmerge SuperColc Calcstar Systems Plus Spellstor and more Software sold only with systems/not warranted fot suitability. All software soles final. ORDERING MAIL ORDER ONLY - 2% cosh discount included/chotge cords add 2%. Prices subject to change, product subject to availability. Arizona residents add 5%. F.O.D. point of shipment Scottsdale. 0-20% restocking fee for teturned merchandise. Warranties included on all products. Personal checks take 3 weeks to clear. CP/M and MP/M ore registered trademarks of Digital Reseorch. Your guide to the world of microprocessors. The Micro-Professor™ -a low cost tool for learning, teaching and prototyping. Here in one attractive package and at a price of only $149.00 is a Z80* based microcomputer to lead you step by step to a thorough knowledge of the world of microprocessors. The Micro-Professor is a complete hardware and software system whose extensive teaching * Z80 is a trademark of Zilog Inc. manual gives you detailed schematics and examples of pro- gram code. A superb learning tool for students, hobbyists and microprocessor enthusiasts, as well as an excellent teaching aid for instructors of electrical engi- neering and computer science courses. But the Micro-Professor is much more than a teaching device. With it you can do bread- boarding and prototyping, de- signing your own custom hard- ware and software applications with Z80, 8080 and 8085 compati- ble code. The standard 2K bytes of RAM is expandable to 4K, and the standard 2K bytes of ROM can be increased to 8K. All this plus a built-in speaker, a cassette interface, and Multitech Electronics Inc. Card No, ^ Check or money * order enclosed □ Visa □ Mastercharge Expires Signature sockets to accept optional CTC/PIO. Bus is extendable. As well as being an exciting learning tool, the Micro-Professor is a great low-cost board for OEM's. Call for details. SSB-MPF Speech Synthesizer Board $129 A vocabulary of up to 400 words based on the TMS 5200 chip. EPB-MPF EPROM Programming Board $169 For all +5V 1KB/2KB/ 4KB EPROMs. Read/Copy/List/Verify Capability. BASIC-MPF Tiny Basic $19 ^ 2KB BASIC interpreter with hardware s> control capability. Machine-code ^ x subroutine accessible. ^ ^ I'm ready to enter the world of microprocessing Call toll free to order. MPF-I Micro- Professor SSB-MPF Speech Synthesizer Board EPB-MPF EPROM Programming Board BASIC-MPF Shipping and Handling I Prict | Oty. Amount $149.00 $129.00 $169.00 $ 19.00 $ 4.95 4.95 s add sales tax. TOTAL (Please Print) Address In U.S. and Canada mall to: Multitech Electronics Inc. 195 West El Camino Real Sunnyvale, CA 94086 California Tel. (408) 773-8400 Elsewhere (800) 538-1542 Outside of North America mall to: Multitech Industrial Corporation 977 Min Shen E Road, 105 Taipei, Taiwan, ROC Tel. 02-769-1225 TWX 19162 MULTIIC, 23756 MULTIIC Circle 291 on inquiry card. User's Column. I was talking with Ezekial, my friend who happens to be a Cromemco Z-2. "I'm getting old, boss/' he said. "You were built in 1977!" "Yeah. In this business, that's old. Look, we've written five books and dozens of columns and hundreds of letters. I do all your taxes and account- ing. I compile all your programs, in twenty languages. I even play games with you." "OK, OK, so what do you want?" "Some rest. A bit of help. Look, I'll make you a deal. I'll help you write books, same as always, but you go get something faster, something new, to do all that compiling and calculating." "Never thought I'd hear you say it," I said. "Better is the enemy of good enough. And you're plenty good enough!" "Could use help, boss. Big responsi- bility, being the only computer around here. Especially now that you're so busy with the Citizen's Advisory Council on National Space Policy stuff and the L-5 Society." (Plug: if you're interested in helping the space pro- gram, join L-5. It's $20 a year; send fee to L-5 Society, 1060 E. Elm, Tucson, AZ 85719. Contributions tax deducti- ble within the framework of the law. Secretary this year: Jerry Pournelle.) "What happens," Zeke continued, "if I get sick?" I thought about it a long time. He's right, of course. He is getting old; and he's utterly spoiled me. I can't con- ceive of writing without a computer. I live in terror that Zeke is going to quit on me. Actually I don't; he's rarely given cause for alarm. A couple of times in the early days we had glitches that brought Tony Pietsch out — always in the middle of the night; nice chap, Tony — but they always got fixed without having to take Zeke away. But not long ago something gave out in the disk power supply, COPIES WITHOUT PROBLEMS: FAST: Turnaround time in hours and days, not weeks. You get your disks when you need them. ACCURATE: Each copied track is checked bit by bit. If it doesn't match your original, it isn't shipped. FLEXIBLE: Standard, double-boot, and copy- resistant formats. 50 copies minimum, no maximum. REASONABLE: Set-up as low as $1Q per disk. Copying only from 30$, copying and 3M disk from $2.00. Other disks and services also available. RELIABLE: Years of disk duplication experience insures a problem-free shipment on time — time after time. For all your Apple® compatible copying needs. THE ALF COPY SERVICE. ALF 144B Estes Denver, CO BD215 [303] 234-0871 keeping Zeke shut down for nearly a week. True, I was out of town at the time, but it could have been a disaster. I needed a second computer. But what? In the middle of the dilemma, Adam Osborne sent me his new Osborne 1. That darned near solved my prob- lem. Osborne's machine is good. The first models had some faulty charac- teristics, but Adam is an honorable man — and also smart enough not to risk his reputation by sharp practices. They're planning retrofits to take care of all major difficulties and most minor ones. The worst of these was the shift lock, which was worse than useless. Then, too, with that tiny screen you needed smooth vertical scrolling (it already had good horizontal scroll- ing). There have been some other minor annoyances, but as I said, Adam's been fixing them. The new Osborne 1 computers — out by the time this is published — will incor- porate the improvements, including true three-key rollover and a decent shift lock, and various other fixes. Those who have already bought the machines will be able to get them retrofitted absolutely free. One thing I thought would be a pain turned out not to be. That's the tiny video screen. Adam has sent me his larger video monitor, which you can connect to the Osborne 1 with a cable, but I find I don't use it. The little screen turns out to be just at the right focal distance when I sit at the console; and for someone like me, who wears bifocal glasses, that's a real boon. I carried the Osborne 1 out to Cal Tech's Jet Propulsion Laboratories for the Voyager 2 encounter with Saturn. There were over a hundred members of the science press corps packed into JPL's Von Karman Center (the press facility). Most had typewriters. One or two had big, cumbersome word processors. At least one was a terminal connected through a network to the parent system in New York. Nobody had anything near as convenient as the Osborne 1, which is quiet and fast responding. 216 April 1982 © BYTE Publications Inc How To Sell More Software With Better User Manuals An intensive one-day seminar on Writing User Manuals That Sell If you're an individual software author or a software company in the business of publishing and selling software, or if you'd like to be, you can benefit from this seminar. Unlike seminars that concentrate on theacademicdo'sand don'ts of technical writing and formatting, this seminar gets down to the business value of the user manual as a marketing and sales tool that helps you get more users and keep them. Developed and conducted by software marketing professionals with over 50 years of collective expe- rience in writing software manuals for the commer- cial market, this seminar is loaded with facts and ideas on these subjects: Manual Design How to make content, organization, page layout, and document format work to your sales advantage. How to publish attractive manuals that speak well of your software without spending a fortune. Training vs. Ref erenca Can one manual do both? How to implement the techniques of tutorial writing into a well organized reference formatthat provides easy access for later questions. Packaging That Controle Point of Sale How to make your manuals work for you at the point of sale to help the dealer present your software in its most competitive light--both on the shelf and on the demonstration machine. Automated Manual Writing How to letthe software document itself wherever possible, and how to use word pro- cessing systems effectively to obtain maximum value from automated publishing tools. Seminar Manual All attendants will receive a de- tailed How To manual on writing and producing user manuals for commercial use. Many past attendants have praised the manual and other handout materials as being worth the price of attendance by themselves. Schedule: Chicago May 21 Boston May 18 Dallas May 25 New York May 19 Los Angeles May 26 Philadelphia May 20 San Francisco May 27 Only $125 With Our Guarantee Price includes lunch and materials. We offer a 10% discount for companies sending more than one person. Get Detaile at ComputerLand Today! Space is limited so make your reservation now. To get enrollment details, sim ply call [303] 471 -9875, or, visit your nearest participating Computerland Store and pick up a complete Seminar Information Packet including an agenda, an outline of the seminar manual, seminar authors' and instructors' resumes and a brochure on Context Inc. content 833 West Colorado Avenue Colorado Springs, CO 80905 User's Column. Everyone came to look at it. ''How can you stand that tiny screen?" asked Eric Burgess, senior science correspon- dent present. (Eric's the chap who first thought of the message plaque to be attached to the space probes. I was there when he got the idea. But that's another story.) He stared over my shoulder. "It's so small." "Try it/' I invited. I got up to give him my place and watched as he realized that when you're sitting at the machine you can read it at least as easily as you can a book. Before the encounter was over, a dozen science writers were ready to go buy an Osborne 1. I also took it to the meeting of the Citizen's Advisory Council on Na- tional Space Policy (which I chair) and used it to take notes during the meet- ing. It was amazing: I was able to type notes and suggestions and ideas into the Osborne 1 without disrupting the meeting at all. The Osborne 1 is quiet and efficient and not at all distracting. In other words, I like the Osborne 1. You can't beat it for the price, under $2000 bucks with over a thousand dollars' worth of software. An Osborne and an Epson printer will put you in the computer/word-processing business cheaper than anything I can think of, and the Osborne 1 is a real computer, using the CP/M operating system and adult software like Word- star and Supercalc and dBase II; it's not a toy. So. For those who haven't a lot of money to spend and want to get going in computers, I don't hesitate to re- commend the Osborne 1 — as a first system. However, it is a limited sys- tem. It wasn't designed for lots of ex- pansion capabilities, and it's never go- ing to be able to use them. But as a first machine, it has a lot going for it, and not just the price. When I first got the Osborne 1, I thought I'd solve one of my problems, which is, how can I have someone entering letters and files and old books while I'm using Ezekial? I certainly am not going to have a multiuser micro- computer, which defeats the whole concept of decentralized computing. Our TRS-80 Model I with Omikron's CP/M conversion will do the job, but it's often in use as the boys check out new games and educational stuff; worse, the TRS-80 keyboard is plain awful, driving my editorial associates crazy. Even the boys get weary of it. No, I needed a second machine, with a good text editor. Aha, says I. I'll use the Osborne 1. Of course the Osborne 1 has only SV^-inch disks, and Ezekial has 8-inch disks, but that's all right. The TRS-80 has both SVi-inch and 8-inch Lobo disks, and those work fine, and under CP/M we can copy files from the little disks to SB-80 The Price Is KTiee. J 2425 Basic system with 600K bytes b~kW« • 1 .2 megabytes: List $3650. • 2.4 megabytes: List $4650. Single Board Technology A Z80A CPU combined with the CP/M * operating system opens new vistas to software availability for eight-bit micros. FORTRAN, COBOL. BASIC. APL. PL/1 and Pascal are available now to accom- modate today's scientific, educational, sophisticated small business and personal system users. • 4MHzZ80ACPU • CP/M 2 operating system • 64K 200ns main memory • 8-inch dual floppy drives • 50-pin expansion connector • 2-senal ports • 2-parallel ports • 4-counter/timers • Hard disk options available. SB-80/10 floppy and Winchester Microcomputer System An 8 inch floppy and an 8 inch Winchester hard disk microcomputer system all packaged in a compact, stylish cabinet. We've combined all the fine features of the SB-80 and added the speed of a Winchester to offer you the storage of almost 12 million bytes. The SB-80/ 10 comes complete with controller power supply, and the single board computer to give you the total system for less money • SB-80/10 Sub-system List $6500. Add-on to the SB-80 10m byte Winchester disk storage • SB-80A/10 List S8500. SB-80 Microcomputer System 600K byte floppy disk storage 10m byte Winchester disk storage • SB-80B/10 List $8900 SB-80 Microcomputer System 1 .2m byte floppy disk storage 10m byte Winchester disk storage Substantial OEM and Dealer discounts available Colonial Data Services Corp. 105 Sanford Street Hamden, Conn. 06514 (203) 288-2524 • Telex: 956014 Mid Atlantic Distributor COMPUTER APPLIED SYSTEMS, INC. 497 Hill Street York Pennsylvania 17403 • (717) 848-2431 *CP/M is a registered trademark of Digital Research. Inc ■■■■■^^■■1 New England Distributor S&M SYSTEMS, INC. P.O. Box 1225 • 2 Washington St Haverhill. MA 01830* (617) 373-1599 J 218 April 1982 © BYTE Publications Inc Circle 90 on inquiry card. THE DAWN OF A NEW ERA "THE COMPUTER-LINE"" E P nhX h a l e N I APPLE H' BM warn Our Volume Sales Are So High That Our Prices Are The World's Lowest - Period! CALIFORNIA COMPUTER SYSTEMS 7710 Async. Serial Int. $135 7490GPIB(IEEE-488) Int. $239 7470 Ana. to Dig. Converter $ 99 771 1 Async. Serial (Term) $135 7712 Sync. Serial Int. $149 7721 Apple Parallel Int. $109 Calendar/Clock Module $ 99 Programable Timer $ 99 MOUNTAIN HARDWARE CPA Multi-Function Card $169 The Clock $229 Supertalker $159 Music System $319 Expansion Chassis $599 Romwriter $139 Ram Plus (32K Board) $149 PRINTERS NEC Spinwriter7710 8023 A EPSON MX 80 MX 80 Ft. MX 100 $ 2339 $CALL $CALL $CALL $CALL ANADEX DP9500/9501 $ 1275 INTEGRAL DATA SYSTEMS Prism 80 $ 1195 Prism 132 Color Printer $1595 MPI 88 G Printer $ 659 99 G Printer $ 749 VISICORP, INC. Desktop Plan III Desktop Plan II Visifiles Visiplot Visitrend/Visiplot Visidex Visiterm Visicalc 3-3 Visipak BUSINESS SOFTWARE STONEWARE $229 DB Master $189 DB Utility Pack $189 MICRO PRO $159 Apple CP/M $229 WordStar $189 Super Sort $ 79 Mail Merger $189 Data Star $539 Spell Star Call Star INFORMATION UNLIMITED Pro Easy Writer $169 Call For Continental, uakin b, Broderbund, Automated Simulations, Avant Edu-Ware, Denver, Howard, Sinus, Sensible, Synergistic Software, Etc. $169 $ 69 $219 $119 $ 79 $179 $119 $119 -Garde, MBI™ COMPARE! WITH CONTROLLER $459 ADD-ON $389 Hard Disks + 8" Disks for Apple, TRS-80 $CALL Apple Computer Products SCALL DRIVES FOR APPLE PRODUCTS • PLEASE CALL OR WRITE FOR CATALOG. MODEMS Mayes Micromodem II $289 Hayes Smartmodem $229 Hayes Chronograph $199 Novation Cat $145 Novation D-Cat Modem $165 Novation Apple Cat II $339 Novation Auto Cat $209 DISKETTES (Boxes of 10) Verbatim Datalife $ 24-95 Verbatim 8" Double-Side/DD $39-95 RAM CARDS Ramex16KCard $ 119 Ramex 128 K Card $CALL Wesper16 KCard $ 119 Microsoft 16 K Card $ 139 Dana 16 KCard $ 119 MONITORS Zenith ZVM-121 Phosphor 15MHZ $119 NEC 1201 Phosphor 20 MHZ $179 NEC 0112 Composite Color $335 NEC 21 12 RGB Color $899 Amdek 300 Phosphor $199 Amdek Composite Color $355 Amdek IBM Compatible Color $899 80 COLUMN CARDS FOR APPLE Wesper80Card $259 Vision 80 Card (Vista) $299 VidexSOCard $259 MISCELLANEOUS APPLE PRODUCTS Enhancer II $ 119 Dana Apple Fan $ 39 Sup R Mod $27-95 IN COLORADO (303) 279 2727 1 1t IViVi'iVi 1 1 1 1 1 f T * * Vi'iTi CALL "THE COMPUTER-LINE" 7 DAYS 1-(800)-525-7877 IN COLORADO SUITE 108 THE GOLD OFFICES 607 10TH ST, GOLDEN, CO 80401 ^ SiU COHTiPUTERWORLD INTERNATIONAL, INC. SUITE 133, P.O. BOX 81, WHEAT RIDGE, COLORADO, U.S.A. 80034-0081 TERMS: RETAIUMAIL ORDER: MASTERCHARGE/VISA ACCEPTED. WE CALCULATE UPS FREIGHT. esaafiSSSSSKSSKKSSSSK^^ Circle 121 on inquiry card. User's Column. the big disks using the PIP utility rou- tine. So all we have to do is to take a disk from the Osborne 1 to the TRS-80 and. . . . It doesn't work. The Osborne disk format is different from the Omikron's format. And, talking to Mike Mc- Culloch of Osborne Computer Cor- poration, I find there's no easy solu- tion to the problem. If there were a "standard" 5V«-inch disk format (as there is a standard for 8-inch disks— the IBM single-density soft-sectored format), then Osborne would use it. Indeed, when Osborne goes to double density for disks, it'll use the new IBM SVi-inch double-density format. But Osborne can't use a standard until one exists. Which means that the only way to get files from the Osborne 1 to Zeke is to send them out the Osborne l's serial Suiifff THE FIRST AND ORIGINAL TRUE SINGLE BOARD S-100 BUSS COMPUTER; THE SOS MASTER MPM CP/M* TURBODOS* '(SINGLE USER & NETWORKING) Z80A or Z80B 4 TIMERS (ZCTC) 64K RAM (64KX1 CHIPS} 2 SERIAL PORTS (ZSIO) 4 PARALLEL PORTS (ZPI01 UP TO 16K EPROM (2732) NEC FLOPPY DISK CONTROLLER (UP TO FOUR 8" DOUBLE SIOED/DOUBLE DENSITY DRIVES} INTELLIGENT WINCHESTER INTERFACE ONBOARD EPROM BURNER (DOES NOT REQUIRE 24V) "beware of incomplete imitations' CP/M is a trademark of Digital Research. TURBODOS is a trademark of Software 2000. r^TJ SIERRA DATA SCIENCES Fresno, California Marketing Division 21162 Lorain Ave./Fairview Park/Ohio 44126/(216) 331-8500/TLX 980131 WDMR port. Now the Osborne 1 has such ports, both RS-232C and modem ports, so that's not impossible, and nowadays Osborne will furnish you with software to accomplish the job (well, to accomplish the Osborne 1 end of the job; obviously you'll have to have appropriate software on the other end to catch what the Osborne 1 is pitching). Moreover, the Osborne 1 format may yet become the "standard" for SVi-inch single-density disks. Accord- ing to McCulloch, the major software houses have been given copies of the specifications as well as an Osborne 1 machine and have been invited to offer software on disks readable by the Osborne 1; Adam Osborne has no in- tention of cutting his users off from the vast marketplace of CP/M software. Just the opposite. So. By now you get the idea. The Osborne 1 is as good an entry-level system as I have seen. The only prod- ucts that come close to it are the new IBM Personal Computer and the Heath/Zenith H-89, and both come with only one disk drive and very little software at a price a good bit higher than the Osborne 1. I did not, however, recommend the Osborne 1 to Arthur Clarke; and I never seriously considered it as the new machine Zeke wanted me to set up as his assistant. It's not that I won't keep mine and use it as a portable for a very long time; but I need more ma- chine than can be bought for $2000, and so does Arthur Clarke. Candidates "Maybe," I said to my mad friend, "maybe I'll get an H-89. I can get it with CP/M and a printer and get a company to fit a case for it. I see ad- vertised a board that will let it talk to 8-inch disks, which will solve the problem of communicating with Zeke. I can end up with a portable." "Good thinking, as long as you think of it as a spare. Your real ma- chine needs an expandable bus." "True. But for a portable. ... In fact," I said in boyish enthusiasm, "maybe I'll get it as a kit and build it so 220 April 1982 © BYTE Publications Inc Circle 369 on inquiry card. BASIC for III Now Hemenway Corporation brings you a BASIC Interpreter for 68000 systems. Easy. Hemenway BASIC is easy to use because it allows interactive software development. Simple program modifica- tions can be made through cursor- oriented edit commands. And debugging can be performed through tracing commands. Accurate. Provides up to 16 digits of precision. Compatible. Implemented to provide compatibility with most 8-bit BASIC programs. Now you can use existing software with 1 6-bit microcomputers. Versatile. Access directories, listings, file manipulation, and other systems functions without leaving BASIC. Simple linkage to assembly-language routines. Clean, uncluttered report formatting with the PRINT-USING statement. Dynamic string management with a complete set of string functions. Error trapping and handling without leaving BASIC. File Support. Full file support for Random and Sequential files. Hemenway BASIC is yet another high- level language supported by the MSP/ 68000™ Real Time Multi-tasking Operating System. Other products are Pascal, Macro-Assembler; Link Utilities, Text Editor 16-digit Floating Point Pack- ages, and Scientific Functions Package. To be released are FORTH, FORTRAN, followed by COBOL. For OEM terms and information contact: Jim Hemenway, Marketing Director Hemenway Corporation, 101 TremontSt., Boston, MA 02 108 (6 17) 426- 1931 TELEX 921735 HGMGNWAY CORPORATION User's Column. I can understand the machine." "Sounds like about as much fun as an appendectomy/' said Mac Lean. I can always count on him to prick any silly bubbles like that. In the middle of all that came another emergency. Dr. Stefan T. Possony, my long-time friend, asso- ciate, and collaborator, decided to get a computer. He'd seen Ezekial, and he wanted him. Or one like him. Not long ago the solution to the problem would have been simple. We'd simply hand money to Tony Pietsch of Proteus Engineering, he would produce an updated clone of Ezekial, and all would be well. Unfor- tunately, Tony's in great demand as a consultant and has just about gone out of the systems-integration business. So, what to get? For Stefan, and for me. It didn't take much research to come to several conclusions. First, a profes- sional system ought to have 8-inch floppy-disk drives. The little disks are fine for entry-level learning systems, but they're just not solid enough— and won't hold enough files — for profes- sional work. Second, the system has to use Digital Research's CP/M operating system. With Xerox, Wang, and DEC (Digital Equipment Corporation) com- ing into the field, CP/M is more than a de facto standard, it's a necessity. Third, the S-100 bus (in a quiet version and built to the IEEE standard, if at all possible) is still the most versatile small-computer system going and will be for some time. An S-100 with a Z80 processor is the way to go. "But why not the new IBM Per- sonal Computer?" one of my sane friends asked. "It has an expansion bus. Not the S-100, true, but a bus. And CP/M-86, and IBM maintenance and — " And 5 x /4-inch floppy disks, which even with IBM behind them are going to be a problem. Furthermore, as of right now (fall, 1981) the local people selling the IBM know nothing about software availability, although with Microsoft's support I expect that to change by the time you read this. The IBM may sweep the field; heaven knows it's a handsome enough unit. I learned to write with an IBM typewriter keyboard, and I've found few computer keyboards up to the Selectric— and the new IBM computer keyboard is even nicer. Indeed, I'm thinking seriously of getting an IBM. But for all of IBM's prodigious reputa- tion, it hasn't a lot of experience with small computers. Until it gains some, I think I'll wait. Besides, IBM Personal Computers weren't available back last summer when Stefan wanted his ma- chine. So. What to get? And how to install it long distance? That really presented a problem. Possony knows nothing about computers, and there aren't too many off-the-shelf S-100 systems. I could get a Vector; although I've no direct experience with them, people 1 trust tell me they're excellent. But then I remembered: I have a good friend, Dr. Colin Mick (Decision Information Services, POB 5849, Stanford, CA 94305, (415) 327-5797), in the Stanford area, where Dr. Possony lives. A quick phone call, and Colin foolishly volunteered to help Stefan. It turned out well. Colin in- stalled a CCS (California Computer Systems) system with a Heath/Zenith Z-19 terminal in Stefan's house. He chose CCS because that's what he has, and he knows some of the CCS design team; the result has been so successful that Colin is now much in demand as a small-systems consultant. Another result is that Possony, already one of the world's most pro- lific writers on foreign affairs and in- ternational politics, has more than doubled his output. He loves his new system; and when you consider that Stefan is a Viennese intellectual, who got his Ph.D. the year after I was born irtBWTPERSONAL COMPUTER" USERS - W YOU DESERVE THE BEST CHOOSE WHAT THE PROFESSIONALS* USE m;m» ACH INC. Circle, Suite B (4(714)540-1333 es Welcome i 64KB-256KB Parity Memory MP-064: $445; MP-128: $620 MP-192: $795; MP-256: $970 User upgradeable Fully assembled, tested & burned- in 1 -year warranty > ASYNC Communication CC-032: $145; CC-132: $275 CC-032 offers 1 serial port CC-132 offers 2 ports Program compatible with IBM's Serial Com. Card ' SYNC Communication CC-232: $295 2 RS232 ports Capable of ASYNC, BISYNC, SDLC, HDLC • Combo Card MC-064 to MC-256 Up to 256KB memory + 1 port of parallel printer port + 1 port of Serial port • Direct Connect Modem Model CC-323 1 port of RS232 Serial link 1 direct connect modem port auto dial, originate/answer • Hardware Prototype WW-068: $75; WW-069: $55 WW-068 wire wrap card (13" x 4.2") WW-069 extender Get both for $95 *The following companies have chosen our products: Context Management, Information Unlimited Software, Network Consulting Inc., Softech Microsystem Inc. 222 April 1982 © BYTE Publications Inc Circle 3 on inquiry card. Vista nvisible or Invincible? t all depends on your perspective. The Vision 80® is a video display card that :jives your Apple terminal an industry- standard 80 column by 24 line display screen with a full 128 character set in- cluding upper and lower case letters /vith three dot descenders. It is compat- ble with all existing Apple™ BASIC software and allows the use of 80 :olumn lower case text with pro- grams written in BASIC, FORTRAN 3 ascal, Microsoft CP/M™ and ASSEMBLER. Full communications driver support allows the Apple II™ :o operate as an intelligent terminal Definitely invincible. Ask Softalk nagazine editors, who rated Vision 80© the Best Apple- /ideo display card on the narket. 3ut the Vision 80® card has an 'Apple" command vocabulary ncluding H-tab, V-tab, HOME, iXT, PR# GRAPHICS). No changes in operating or programming procedures are necessary to produce what- ever sophisticated displays you require. And it doesn't interfere with the operation of popular Apple™ compatible peripher- als. Except for the enhanced display, it's as if you had never installed the Vision 80® in your Apple II computer. Definitely invisible. Ask your local computer dealer for a demonstration of the invincible, invisible Vision 80® video display card by Vista Computer Company. Or correspond with us directly: Vista Computer Company, Inc. 1317 East Edinger, Santa Ana CA 92705, (714) 953-0523. Toll free order line: (800) 854-8017. Be sure to inquire about our new Vision 40, a softscreen program- mable character generator for Apple II™ computers. It's great for graphics and perfect for foreign language applications. Perceptive Perspective Circle 427 on inquiry card. COMPUTER COMPANY, INC. 131 7 East Edinger • Santa Ana, CA 92705 714-953-0523 800-854-801 7 ©1981 Vista Computer Co., Inc. ^ppte and Apple II are trademarks of Apple Computer Inc. CP/M is a trademark of Digital Research Inc. Circle 5 on inquiry card. more . . . SPECTACULAR OFFERS l^JBASF MAXELL WABASH OPUS We stock the complete line of BASF diskettes, reel-to-reel tapes, mag cards, disk packs and cartridges. We also carry MAXELL, OPUS and WABASH products. All are 100% certified and fully guaranteed. Box of 10 diskettes: 5V4 ■ 8" OPUS ss/sd $20 $21 BASF ss/sd 23 24 WABASH ss/sd 23 24 MAXELL . TOO LOW TO QUOTE. CALL 5 1 /4"-10 sector-now available Sectoring must be specified. 5 1 /4 " or 8" Vinyl Storage Pages 10/$S LIBRARY CASES 8" Kas-sette/10 $2.99 5Va" Mini Kas-sette/10 . . $2.49 imuLqTiom p. o. box dciTOGf Colorado |M We'r JF 're it for your hardware and software needs. MARCH SPECIAL SuperCalc TM $ 236 THE APPLICATIONS GROUP a (214) 749-5513 I I I PO Box 992 Ca"on!on TX 75006 I I I I — B WMM Circle 319 on inquiry card. 226 April 1982 © BrTE Publications Inc Circle 48 on inquiry card. Circle 35 on inquiry card. ODrnPUTCR WAREHOUSE CALL TOLL FREE 1-800-528-1054 ATARI Special 32 K 800 System 800 w/32K, recorder, star raiders, joysticks Call Above w/48K Call 800(16K) 400 $670 $340 810 Disk Drive .... 825 Printer 850 Interface 410 Recorder 830 Modem $440 $590 $170 $ 75 $155 16K Memory 32K Memory $70 $125 MODEMS Novation CAT $140 D-CAT $155 Apple Cat II Auto Cat $349 $235 PRINTERS C. Itoh F-10- Parallel F-10- Serial 55CPS - Series . . 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INC data systems SPECIAL WORD PROCESSING SYSTEM Altos 8000-2, Teievideo 950, Diablo 630RO, Word Star, Cables $5830 above w/TELEVIDEO 910 $5500 VIDEO TERMINALS Adds Viewpoint $530 Attos Altos i Call Soroc IQ120 $630 ig 130 Call IQ135 Call iqho Call Teievideo 910 C $570 912 C $675 920 C $735 925 C $730 950 C $915 Zenith Z-19 $680 DISKETTS Elephant 5%"0. Sector (100). .. . $215 Scotch 5M"0.10.16Sector (100) $250 8" 0.32 Sector (100) .. $260 COMPUTERS Altos ACS 8000-1 5 ACS 8000-2 w/CPM* Alspa ASCI-1 ASCI-2 California Computer Systems IBM Personal Computer NEC Northstar Advantage Horizon II 64KQD Teievideo Systems System I System II TS-802 TS-802H Zenith Z-89 48Kw/CPM" Z-90 64Kw/CPM R Both above w/supercal DISK DRIVES Lobo Apple 1st Drive Apple 2nd Drive $3850 $2650 Call Call Call Call Call $2990 $2690 $2255 $5045 $2700 $5050 $2160 $2385 $400 $350 compurcR WAREHOUSE 2222 E. Indian School Rd. • Phoenix, Arizona 85016 Order Line: 1-800-528-1054 gMfc ■■■■ Other Information: 602-954-6109 NWW mmmm Store Hours: Tues.-Fri. 10-5 MST Saturday 10-2 MST Prices reflect 3% cash discount. Product shipped in factory cartons with manufacturers warranty. Add 2% a minimum of $5 for shipping and handling. Personal checks will delay shipping two weeks. Prices & availability subject to change without notice. User's Column. text and moving them; and, much as Wordmaster does, it allows you to use the macro-command capability for all the really complicated stuff. WRITE also has the menu available at any time: simply hit Escape and you'll see a whole list of instructions, pages of them if you like. But you don't see them unless you want to. I wish Wordstar had taken that approach. I do recommend Wordstar for some purposes. First, it works on a terminal. Because it knows where the ends of pages are, it can do indexing. It for- mats on screen; what you see is what you get, an intolerable disadvantage when what you want is a simple double-spaced manuscript (who wants his on-screen text double-spaced?) but a real boon if you're publishing a newsletter or other matter requiring holes for illustration. It has a good mail-merge utility. If you can use any of those features, Wordstar is the only program that has them. Incidentally, there are a couple of candidates for Wordstar's crown, one of them being MINCE (acronym for MINCE Is Not Complete EMACS) which emulates EMACS, the MIT (Massachusetts Institute of Tech- nology) full-screen editor and is cer- tainly the best editor if you want to write LISP programs. MINCE works on terminals (but not with memory- mapped video; at least I've never been able to get it running on Zeke). Now that the Godbout with the H-19 is up and running, we'll have a more thorough report. But when it comes to creating text, you won't beat WRITE. Or so say I. muSimp/muMath Some time ago, I got a copy of muSimp/muMath from the Soft Ware- house. Marketing of these programs has since been taken over by Micro- soft, which has probably enhanced the documentation — at least it usually does. There's nothing quite like muMath [For another review see 'The muSimp/ muMath-79 Symbolic Math System" by Gregg Williams, November 1980 BYTE, page 324]. The basic concept comes from MACSYMA, the sym- bolic-algebra programs continually under development at MIT's computer laboratories, which run on the DEC PDP-10. Obviously, there is no way to put the full power of a PDP-10 into a microcomputer — although the God- bout 8085/88 comes closer than I would have thought possible a few years ago. MuMath consists of a core plus a whole series of auxiliary routines. The programs are written in LISP, but you don't have to know LISP to use them. (It would help, though. Boy would it help.) MuSimp is another package of routines which will also work with muMath. Together they will do a sur- prising lot of useful work. You could, for example, write a Visicalc in muSimp/muMath, and I suspect it would work quite well. There are also examples of how to write a database system using them. In other words, muSimp /muMath have a lot more power than appears on the surface (or, indeed, is hinted at in the advertisements). Their primary purpose, though, is to do symbolic math. And here I have to confess a fault. When I first got muSimp/muMath, I tended to com- pare them to MACSYMA, and of course these programs written for 8-bit microprocessors came up wanting . How could they not? What I should have done was find someone who never had access to MACSYMA and ask what she thought of them, and recently that's what I did. "Wonderful," said my lovely friend. "I've never even suspected you could do things like that on a computer. J RAM New 5 1 2K RAM card for the IBM Personal Computer. Parity and paging hardware. Up to one and a half megabytes per system using 3 JRAM's. Included is flop- py with software to allow any por- tion of memory to be used as simulated floppy drive. All RAM locations are socketed and par- tially stuffed cards are available on special request. $1500 Tall Tree Systems 1036 Los Altos Avenue Los Altos, CA 94022 (415)941-8748 Circle 404 on inquiry card. 228 April 1982 © BYTE Publications Inc THE MISSING LINK <^ $249* jgj Adapt IBM ET50, 60. or 75 to Apple II or III with our Missing Link for word processing quality output. • Does not affect normal typewriter operation • Typewriter still qualified for IBM maintenance con- tract • Interface isolates the Apple from the typewriter See our full page ad in May 1980 BYTE Check with your local Apple dealer or to order call: 1-800-845-2712 (In S.C., call 1-800-922-5528} If you need word processing software, we offer ManuScripter in two versions Beginner $95, Advanced $195 "S C residents add 4% sales tax M Systems 2301 DEVINE STREET • PO BOX 5144 COLUMBIA. SC 29250 • (803) 254-0804 Circle 98 on inquiry card. FOR UCSD PASCAL* SYSTEMS $650 - PDBASE an Entity Relational Data-base. Complete with English query language, for- mated screen, procedure lan- guage, data security, multiple users, validity checking and example relations. $300 - Program interface for PDBASE $ 25 - PDBASE users manual $125 - Interactice spelling checker $100 - Complete LISP interpreter. IOTC Inc. 910 Sully /Laramie, WY 82070 ^Trademark Regents Univ. of Calif. (307) 721-5818 Circle 215 on inquiry card. Made by Seikosha, AXIOM'S new GP-100 is the finest printer a little money can buy. It uses standard 8-1/2 x 1 1 paper and has AXIOM'S fabulous graphics interfaces for Apple, TRS-80, Atari, PET, HP and more! See the GP-100 at your AXIOM dealer today! Seikosha is the leading company of the worldwide Seiko Group. AXIOM CORPORATION 1014 Griswold Avenue, San Fernando, CA 91340 • Telephone: (213) 365-9521 «TWX: 910-496-1746 Circle 47 on inquiry card. Circle 436 on inquiry card. STARTING YOUR OWN MICROCOMPUTER BUSINESS Starting your own microcomputer business is easy if you know the right steps to take. Two volumes of the new book Your Fortune In The Microcomputer Business describe the things you should know to start right and to build your business successfully. Many people have good ideas for a successful microcomputer business. But they don't know how to put their ideas into action. These people are plenty smart. That 'snot the problem. The problem is in knowing simple things: How to analyze the market. How to select the right product or service. How to get enough startup money. How to plan your growth and success. The answers to these problems are not hard to understand. All you need is the right information. Your Fortune In The Microcomputer Business gives you the knowledge tools to start right, grow and prosper. This practical reference manual has no hocus-pocus. It does not tell you how to do astrology or dating services. It does give you clear, complete, step-by-step instructions on how to get started right and insure your success! Volume I Includes: ■ The hottest trends in the market ■ The seven best test markets ■ How to read between the lines at a trade show ■ 107 ways to reach your market ■ Examples of the best ads in the business ■ How to get free advertising ■ The 21 steps to set up your business ■ How to start a manufacturing business ■ How to write a newsletter ■ How to give a seminar ■ How to start a service business * mm *° ■ How to package software for the mass market ■ How to be a highly paid consultant ■ Franchising— the good, the bad and the ugly ■ Interviews with six successful microcomputer businesses ■ How to use the RLC factor to be street smart, lean, mean and successful Volume II Includes: ■ Strategies for growth ■ Straight facts on incorporation ■ How to build your organization ■ How to manage cash flow ■ How to develop your accounting system ■ How to manage employees, wages and salaries ■ How to survive a cash crunch ■ What to do if things get really bad ■ How to maximize your profits ■ How to grow by acquisition ■ How to value your business ■ How and when to sell your business WRITE OR CALL-DONT WAIT! i Getting Started Hi Volume II Growth, Survival and Success bjHCTOtWRD Wildfire Publishing, P.O. Box 420 -DK Carpinteria, CA 93013 Ph. (805) 684-1489 Please send the following book(s) by return mail. I understand if I want to return them for any reason within 30 days of receipt, I can do so and get a prompt full refund. □ Your Fortune In The Microcomputer Business Vol. I, Getting Started, $20.00. (Postpaid) D Your Fortune In The Microcomputer Business Vol. II, Growth, Survival and Success, $20.00. (Postpaid) Calif, residents please add $1.20 each sales tax. Name Street City _ _State. Zip . Enclosed is . Card# Ex. Dt Signature _ - or charge my Master Charge D or Visa D M( Interbank # 1982 Wildfire Pub. User's Column. Items Reviewed Ashton-Tate Suite 1510 3600 Wilshire Boulevard Los Angeles, CA 90010 (213) 204-5570 WRITE (Writers' Really Incredible Text Editor) California Computer Systems 250 Caribbean Drive Sunnyvale, CA 94086 (408) 734-5811 Model 2210A S-100 Compupro-Godbout Co. Oakland Airport, CA 94614 (415) 562-0636 8085/8088 Dual Processor $39 $2350 6 MHz $425 8 MHz $525 Cornucopia Software POB 5028 Walnut Creek, CA 94596 (415) 524-8098 Microproof TRS-80 Model I or III TRS-80 Model III or $89.50 CP/M $149.50 Optional Correcting Feature $60 Innovative Software Applications 260 Sheridan, Suite 300 Palo Alto, CA 94306 (415) 326-0805 Spellguard 2.0 Micropro International Corp. 1299 Fourth Street San Rafael, CA 94901 (415) 457-8990 Wordstar 3.0 Microsoft 400 108th Avenue NE, Suite 200 Bellevue, WA 98004 (206) 828-8080 ' $295 $495 muSimp/muMath BASCOM BASIC Compiler CP/M and Apple CP/M and Apple 52 $395 Osborne Computer Corp. 26500 Corporate Avenue Hayward, CA 94545 (415) 887-8080 Osborne 1 portable computer Workman & Associates 112 Marion Avenue Pasadena, CA 91106 PDATA Minimum Data Base $17 (po $84.50 230 April 1982 © BYTE Publications Inc One Concept 1000 Supports 16 CP/M User Stations r -'■ \ ■ » r~ \ 1 t44~H4-++*4-m--^ N I 1 \ 1 -5kp- Jsei Multi-Tasking Microcomputer System COLUMBIA 1 DATA PRODUCTS, INO TIME MANAGER FOR APPLE" II AND II PLUS LIST 150.00 APPLE" SOFTWARE 125.00 MICROPRO WORDSTAR* 245.00 SUPERSORT* 130.00 MAILMERGE* 85.00 DATASTAR* 207.00 HAYDEN APPLESOFT COMPILER. 145.00 MICROSOFT CP/M® BASIC COMPILER 315.00 TASC APPLESOFT® COMPILER..., 150.00 FORTRAN 80 165.00 COBOL 80 550.00 ALDS 105.00 ADVENTURE 24.95 OL YMPIC DEC A THALON 21.95 Microhouse continues to feature the best savings on the best software. TERMINALS TELEVIDEO 950 CALL 925 CALL 920 CALL 912 CALL 910 CALL PRINTERS C.ITOH APPLE" ACCESSORIES MOUNTAIN COMPUTER MULTII/O 178.00 CP/M" SOFTWARE ASHTONTATE dBASEII Version 2.0 599.00 VIDEX VIDEOTERM .... 290.00 KEYBOARD ENHANCER. 105.00 PRO/WRITER SERIAL . . . 650.00 PRO/WRITER PARALLEL 535.00 STARWRiTER I SERIAL .... CALL STARWRITER I PARALLEL . CALL ALL C. ITOH PRINTER ACCESSORIES CALL EPSON MX-100 CALL MX-80FT CALL MX-80 CALL EPSON GRAFTRAX CALL ALL EPSON PRINTER ACCESSORIES CALL ANADEX DP-9501 CALL DP-9500 CALL DP-9001 CALL DP-9000 CALL DP-8000 CALL DP-8000 for APPLE CALL ALL ANADEX PRINTER ACCESSORIES CALL OKIDATA MICROLINE 84 CALL MICROLINE 83A CALL MICROLINE 82 A CALL MICROLINE 80 . . CALL MICROSOFT Z-80 SOFTCARD 299.00 16KRAMCARD 150.00 VISICORP VISICALCf CALL VISIDEX-f 159.00 VISIFILEi 200.00 VISIPLOTf 149.00 VISITERMf 128.00 VISITREND-VISIPLOTf. . . 220.00 DESKTOP PLAN llf 160.00 MODEMS HAYES CHRONOGRAPH RS-232 COM PA TIBLE CLOCK/CALENDAR FOR SMALL COMPUTERS. ADDS DIMENSION OF PRECISE TIME-KEEPING TO ALL RS-232-C COMPATIBLE COMPUTERS, USED IN CONJUNCTION WITH USER-DEVELOPED SOFTWARE, THE CHRONOGRAPH CAN LOG REPORTS AND PROGRAMS BY DATE AND TIME. COMPUTER ALARM FEATURE, STAND ALONE UNIT POWERED INDEPENDENTLY, BATTERY BACK-UP AND WRITE PROTECT SWITCH. LIST: 249.00 SUPERSOFT TERM II . 737.00 DIAGNOSTICS II 84.00 DISK DOCTOR 84.00 FORTRAN . . 218.00 SSS FORTRAN with RATFOR. 285.00 TINY PASCAL 74.00 208.00 SMARTMODEM 230.00 MICROMODEM II (APPLE) 307.00 MICROSOFT BASIC 80 285.00 BASIC COMPILER 315.00 COBOL 80 568.00 FORTRAN 80 345.00 muSIMP-muMATH 215.00 MACRO 80 140.00 NOVATION APPLE-CAT 325.00 LIST: 389.00 AUTO-CAT 213.00 D-CAT 156.00 MICROPRO WORDSTAR 3.0* 299. 00 SUPERSORT* 7 70.00 MAILMERGE* 105.00 DATASTAR* 244.00 The Microhouse Order Center is Open from 9:00 AM until 8:00 PM Eastern Time Monday through Friday. Visa and MasterCard Welcome. 1 Trademarks of MicroPro International. ^Trademarks of VisiCorp. CP/M is a registered trademark of Digital Research. APPLE is a registered trademark of Apple Computers. VISICORP VISICALC NEW FOR APPLE*' AND IBM CALL FORORDERSPRCEQUOTESAVAILABILITY H nm^k r* ~k~» ft / OUU DCD D IN PENNSYLVANIA P | P.O. BOX 498 BETHLEHEM, PA 18016 NEW C. ITOH F-10 PRICES AND SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE ALL ITEMS SUBJECT TO A VAILABILITY DAISY WHEEL PRINTER (REPLACES STARWRITER II PARALLEL AND SERIAL) 1 6 INCH WIDTH, FRICTION FEED OR OPTIONAL BIDIRECTIONAL TRACTOR. ETX/ACK, X-ON/X-OFF PROTOCOLS. LOW PROFILE DESIGN. . . ONL Y 6 INCHES HIGH! 40CPS. PARALLEL OR SERIAL Microhouse Presents CALL SORCIM SUPERCALC LIST: 295.00 219.00 CALL FOR THE LATEST MICROHOUSE SA VINGS ON THE COMPLETE LINE OF MAXELL DISKETTES. Hour Ordering With Microline NEW C. ITOH PRO/WRITER SERIAL 120 CPS, BUSY READY, X OWX-OFF. CURRENT LOOP LIST: 885.00 650.00 The Microcomputer People from Microhouse introduce yet another innovation to computer shopping: Microline. Microline is a computerized order-entry system, similar to accessing time-sharing systems. Microline is easy to use. All you need is a computer, a modem, a phone, and to follow these easy steps: PREMIUM PACKAGE 16KRAMCARD Z-80SOFTCARD VIDEX VIDEOTERM D INVERSE CHARACTER SET □ 40-80 COLUMN SWITCH CPM' USERS GUIDE by Tom Hogan LIST: 775.00 619.00 1 Dial 215-868-1 230. 2 Microline will answer in one ring. (If not already in use) 3 A tone will be transmitted through the phone. 4 Connect your modem to your phone. 5 Hit the 'RETURN' key on your computer. A self-explanatory sign-on message will appear on your screen. Q Follow the instructions to shop and order through Microline . 7 Payments by check, money order, C.O.D., MasterCard, or Visa only. The Microcomputer People. Microhouse : Circle 272 on inquiry card. Circle 442 on inquiry card. Xr^MX systems 68OOO System 2 System 2 includes: • 68000 processor at 8MHz • 32 bit registers, operations • 7 vectored interrupt levels • 256KB parity checking RAM • TOMB Winchester hard disk • 960KB floppy disk • Graphics display monitor • Multibus™/IEEE architecture • XVX multiuser operating system • Option; UNIX™, CP/M™ • Screen editor, filer, linker • Language: (Pascal, C, COBOL, FORTRAN, BASIC, or Assembler) • Option: add 10MB Winchester with 10MB tape backup • Option: on site service Software: A« Counts™ accounting and inventory. Bizgraf ™ business color graphics. Tektext™ scientific word processor. TeleSoft-Ada™ to DOO specifications. • UNIX™ of Bell Laboratories • CP/MTM of OiQital Research • Multibus™ of Intel Corp. • Ada™ Oept. of Defense Representatives worldwide. IMMEDIATE ATTENTION! Please send specifications on: □ System 1 ($2,000) (board only. 128KB RAM) D System 2 ($8,500) (with 10MB Winchester) Name Company City Zip Phone State Phone: (319)344-0550 Cable: XAVAXCORP XAVAX Corporation 300 Northwest Tower Bettendort, Iowa 52722 8482 User's Column. How long has this been going on?" I shrugged. "You mean I went through three semesters of calculus and did ALL THOSE PROBLEMS while you had a computer program that would do dif- ferentiation and integrals? And I mashed through Physics I and II and solved problems with a hand calcu- lator when all that time Ezekial could have done my homework?" By now she was screaming. "Uh, well — " Under the circum- stances I did the only sensible thing a man could do. I hid behind my wife. But my lovely friend did have a point. True, muSimp/muMath are limited in what they can do, but they can do differentiation, integrals, and algebra. They can factor and expand polynomials. They can do matrix op- erations and simplify equations, and do it all symbolically, the way you'd mess around with the equations using pencil and paper. The programs aren't perfect. They tend to run out of memory easily. The way to escape that is to set up a kind of subprogram consisting of those ele- ments of muSimp/muMath that you need for your particular problem, leaving out all the parts that won't af- fect what you're doing. For example, you can configure a system that understands trigonometry and com- plex numbers but doesn't know that matrices and integrals exist. And so forth. There are other limits. The docu- mentation isn't exactly encrypted, but it's pretty dense. You really have to want to use the programs to dig your way through that stuff, and as I said earlier, it would help a lot if you understood LISP. The authors of the muSimp documents plainly do under- stand LISP, and although they don't expect you to, they keep hoping you will. Still in all, there's no real competi- tion for muSimp/muMath. If you want to do symbolic algebra, if you want to use your computer to help you get through Calculus 102 and Physics 203, then you probably need muSimp/muMath. Recommended for those who need it, with reservations as noted. BASCOM Improves More good news. Microsoft has done it again. It has improved its BASCOM BASIC Compiler. What Microsoft has done is two- fold: it's added program CHAINing with COMMON storage, meaning that you can break a program apart into pieces and execute it in parts, passing variables to each chunk as called. This greatly reduces the size of the program code that must be in memory at a given time, which means that it saves free memory and that you can run bigger programs with more variables. Second, Microsoft has greatly cut down on the run-time package, so the total size of the programs is — or can be — smaller, and also larger programs can be compiled and linked. More good news. Microsoft has partially dropped the restrictive licens- ing provision that made you pay a royalty on any program you sold that had been compiled with BASCOM. The bad news on that front is that it has dropped the royalty requirement only for the old BASCOM; if you want to use the new, with the CHAIN and COMMON keywords and smaller run-time package and all that nifty stuff, you still have to pay for each copy you sell. Alas. But I suspect free enterprise will end that; it's only a matter of time. Meanwhile, the new BASCOM is very nice indeed. Take a trivial exam- ple: an old Star Trek game I've been playing with. As you might suspect, my Star Trek is the ultimate game, with invisible Romulans, and shields for the Klingons, and enemy bases, and attacks on Federation bases, and Federation trading ships, and black holes, and — well, you get the idea. The game was originally written in EBASIC, a public-domain precursor to Gordon Eubanks' CBASIC. I added to it and translated it into CBASIC, but eventually the program outgrew that. Besides, it was getting awfully slow. What I wanted to do, therefore, was 234 April 1982 © BYTE Publications Inc CP/M ® ANYONE CAN USE CP/M WITH SUPERVYZ SUPERVYZ is a revolutionary soft- ware concept that serves as a mediator between the user and CP/M, requesting information in plain English and translating the response into the form CP/M recognizes. Users are led from one application to another in a courteous and step-by- step sequence of menus. Aided by descriptive error messages and computer-assisted tutoring, the operator avoids mistakes and is advis- ed of the next step in a polite and friendly manner. EXPAND YOUR MARKET AND LOWER COSTS As a Dealer, SUPERVYZ allows you to sell CP/M computers and applica- tion software to non-technical markets, without the added expense of teaching the operating system. EPIC supplies the menus or you create your own to meet the exact needs of your customers. Because SUPERVYZ is compatible with over 2,000 programs and 300 com- puters, you can bundle software from different suppliers and SUPERVYZ does the teaching. This eliminates costly after-the-sale handholding. For further information about EPIC SUPERVYZ, call or write us today. Supervyz is a trademark of Epic Computer Corporation. CP/M is a Trademark of Digital Research. Circle 172 on inquiry card. j [software Epic Computer Corporation 7542 Trade Street San Diego, CA 92121 Tel. 714-695-3560 NOW SOLD THROUGH DISTRIBUTORS IN POPULAR FORMATS 800-421-0814 DEALERS ONLY PLEASE I ;■ jr™ 1 #■ — ALP'HACOfl INTRODUCED THE mLPHhCOM 42 MP-SELlCThBLE INTERFACE: t 120 LIWES PjER MINUTE. TAKES 0NL t 14 SECONDS TO PRODUCE A FULL ES@ DOT LINE CRT DISPLAY IN HARDCOPV. Results of the ALPHACOM 42 Thermal Printer Quality graphics and symbols for business and pleasure. Visa FAST -QUIET-LOW COST The remarkable ALPHACOM 42 high speed 40 column thermal printer is now available through this mail offer for only $199.95.* For Apple, Commodore, Atari and other home computer users, this is the opportunity to own one of the most reliable printers ever introduced. It's a fool-proof printing mechanism that is backed by field experience with more than a million similar units in industry, government and education, plus a 90 day warranty. Fast, quiet and easy to operate, the ALPHACOM 42 prints up to 120 text lines per minute! Dump a 24 line CRT in 14 seconds!! Order your ALPHACOM 42 today using the convenience of Master Card or Visa. Call for immediate action, or mail your check to ALPHACOM. 800 S38 • 7047 * Interface Cables available for as little as $24.95. Alpha com ■ 2323 S. Bascom Avenue, Campbell. CA 95008 MasterCard User's Column translate it into Microsoft BASIC and compile it; but I couldn't because the program was just too large. I could break it into pieces for the Microsoft interpreter, but that was even slower than CBASIC. Comes new BASCOM and I've done it. Now I have a setup program which invents the game universe and makes the maps; then it calls in another program which processes commands; and every now and then still another program comes in and massages the data. It all works, letting me have a Star Trek so complicated that even I am beginning to think it's finished. Anyway, that's how the new com- piler works. On a more serious note, it will compile my tiny database. And here I have a problem. Should I review software that I have written? Certainly I have an obligation to tell you it's mine. I try to be objective, but certainly I could overlook flaws in my own programs. Minimum Data Base Minimum Data Base grew like Topsy. It started a long time ago with a thing called the People's Data Base by Yogesh Gupta and others. It was, in fact, the very first program I ever got running. When I bought Zeke, Mac Lean and Tony Pietsch handed me Debbie (a Microsoft-like BASIC that came with the Icom disk drives and, ugh, FDOS operating system); and they handed me a listing of the People's Data Base, "Get that running," they ordered. So I tried. Lord I tried. And I cer- tainly learned that semicolons are not colons, that single quote marks are not double quotes, that BASIC has a very precise syntax and improvements are not tolerated, and that I needed to keep my temper well enough so as not to throw anything heavy at Ezekial. Eventually I got it running. It wasn't a bad little program; more to the point, it was well structured, with a main routine and a series of subrou- tines, some of which themselves called other subroutines. There were no GOTO statements except within sub- 236 April 1982 © BYTE Publications Inc Circle 20 on inquiry card. N EPROMS \OTMOI£EY! Two year warranty. PROM IT Apple It EPROM PROGRAMMER — Powerful. Versatile. Best value for your money. UNBEATABLE PRICE — The RomWriter sells for $175. The Apparat sells for $149. PROM IT is yours for $129.50. BURN EPROMs! Not money! Circle 287 on inquiry card. PROM IT APPLE II EPROM PROGRAMMER Now you can enhance the power of your Apple II system and make substantial savings by programming EPROMs yourself, speedily and reliably. VERSATILITY — MPC Periph- erals proudly introduces PROM IT, the most versatile EPROM burner in the market today for your Apple com- puter. Unlike other burners that program only a single type of EPROM, PROM IT pro- grams 8K, 16K and 32K EPROMs such as the 2508, 2516, 2532 and 2732 with a simple change of a personali- ty module. DOWN — The Zero Insertion Force socket and EPROM power-down switch permits EPROMs to be easily installed or removed without powering the Apple down. FLEXIBILITY — The powerful disk-based software manipu- lates memory blocks, disk files and EPROM code to pro- vide a flexible EPROM pro- gramming environment. "Apple II is a registered trademark of Apple Computer, Inc. RomWriter is a registered trademark of Mountain Computer, Inc. Apparat is a registered trademark of Apparat, Inc. Prom It is a registered trademark of MPC Peripherals Corp. MEMORY READABILITY — Unlike some competitive brands, the PROM IT'S mem- ory mapped design allows use of EPROM for machine code routines executable by the Apple's 6502 microproc- essor. CODE STABILITY — The switch selectable Write Pro- tect feature ensures code sta- bility by preventing accidental overwriting of EPROMs. VARIETY OF APPLICATIONS — Apple owners can run EPROMs for several applica- tions including custom char- acter generators, custom sys- tem monitors, custom driver software, product emulators, operation testing, energy and instruments control, data acquisition, software security MPC Peripherals Corp. 9424 Chesapeake Drive San Diego, CA 92123 Tel: 714-2780630 SOFTWARE DEVELOPMENT TOOLS FOR INDUSTRY CP/M CROSS-ASSEMBLERS Fast, comprehensive cross-assemblers to run under CP/M.* Extensive pseudo- ops Include full listing control, nested conditionals, mnemonic synonyms, and inclusion of external source files. Generate object file, assembly fisting, and symbol table from source code for nine popular microprocessor families. XASM05 6805 XASM09 6809 XASM18 1802 XASM48 8048/8041 XASM51 8051 XASM65 6502 XASM68 6800/6801 XASMF8 F8/3870 XASM400 COP400 Assemblers . . . $200.00 each Manual only. . . $ 25.00 8048 DEVELOPMENT PACKAGE Now you can use the 8048 family of single-chip microcomputers without buying expensive equipment. Develop 8048 software with the XASM48 cross- assembler. Then plug our EPR-48 board into your S-100 system to program the 8748 EPROM version. 8048 Development Package . . . $574.00 EPR-48 alone $449.00 EPROM SIMULATOR BOARD Debug dedicated systems quickly. Our PSB-100 PROM Emulator is an S-100 board with up to 8K of RAM. Cable with 24-pin plug replaces 2708 or 2716 EPROM(s) in your target system for ins- tant program testing PSB-100 EPROM Simulator . . . $445.00 w/2K RAM * Trademark of Digital Research 804 SOUTH STATE ST DOVER. DEL. 19901 302-734-0151 I Visa and Mastercharge accepted. We ship 8" slngie- I density and Softcard + 5.25" diskettes. Ask us I about other formats. OEM AND DEALER INQUIRES I INVITED. I + Trademark of Microsoft 238 April 1982 © BYTE Publications Inc User's Column. routines. None of this grasshopper jumping about that so ruins BASIC'S reputation. The program was limited, and soon I ran into the limits. So I began to im- prove it. The sort algorithm used was a bubble sort. That wouldn't do, so I put in a Shell-sort algorithm. There were no disk operations. I fixed that. The command menu was processed in- efficiently, so I rewrote that and renamed most of the commands. The "delete entry" system was asinine, and I set up an entirely new way to handle that. And so forth. Year after year the silly thing grew — and I found I was using it for everything. It keeps phone numbers and addresses. It keeps the list of mem- bers of the Space Council and the L-5 Board. When the Boy Scouts go hik- ing, a PDATA (after the original Peo- ple's Data Base) lets me make lists by meal (what are we eating for Thursday dinner?), or by who is carrying what (who's got Friday's lunch?), and all that. When I do an anthology, a PDATA file keeps track of who has how many shares and what they've been paid. When new royalties come in, it calculates what the new payment is and then writes the cover letter, makes mailing labels, and writes the checks. Versatile. And darned easy to use. "You ought to sell it," said Barry Workman of Workman Associates. "Let me handle it for you. It won't make you rich, but what do you care? People out there need the program." "Maybe," said I. 'What if— gulp— what if someone reviews it and doesn't like the documentation? I can stand not being thought an elegant program- mer, but — " "Don't worry about it. I learned to use it, didn't I?" I shrugged. "Also, look, there's very little new in there. True, I didn't steal it from Gupta and the People's Data Base; there probably aren't ten lines of code left from their original. But it's all very straightforward code. Nothing elegant at all." "That's the value," Workman said, "Look, lots of people want a general- purpose do-all program, which is what this is. I notice that when you did all that statistical analysis, you used your PDATA thing." "Yeah." "And your Christmas cards are on it, and you used to keep your check- book balance — " "I don't do that any more. I use a Journal now." 'Yeah, but you used to," Barry said. Eventually he wore me down. So. I mention PDATA, a small database and do-all, available from Workman Associates. If I didn't already have it, I'd probably buy it; I can't conceive of living without it, and I wouldn't have time to write it again. It is useful. And it's in both CBASIC and Microsoft BASIC, with the Micro- soft version compilable by BAS- COM— except that BASCOM will not compile the general program because it won't compile anything with arrays defined by variables. PDATA creates databases and dimensions them ac- cording to the number of fields you've specified, but BASCOM wants to know those dimensions in advance. This means that you can compile FONES (the telephone program) or NAND (name and address) or any set whose structure you know in advance, but you can't just compile PDATA. On the other hand, one reason PDATA is so useful is that you can run it interactively in interpreted Microsoft BASIC and write your own special-purpose routines (such as the one that determines what my contri- butors ought to be paid, given the total royalty). If you know BASIC at all, you can do a lot with PDATA. So. Useful, yes. But it is not a rival to dBase II and doesn't claim to be. All it claims to be is a very useful little general-purpose data handler that pro- vides a structure to let you mash data. And it will do all the statistics taught in elementary stat courses: sums, averages, standard deviations, me- dians, means, and correlations be- tween two variables. I've always liked it, and I'm happy to share it. Next time, more on Zeke's new friends and a lot more on financial programs. I Circle 62 on inquiry card. Screen Director ^ «• color nZ? 1 ^ 1 ^ ween Screen OhwSr^LS' ° n * s,s °. boardroom present!?, '" . - - "■anagemenfb^ g£* rc^r 03 ^ 9 It Wfcri Screen Director™^ c °lor displays w^ H s ^ rou 9hany tne touch «f * * r "— a "at s Graphics UUCiMO es'n a variety of fonts and colors. ^EE25K? »*th cinema. •E^SXS"*'*'** F °r informati •"your area, call (617) £{33*™" Direct °^ « a product of eus/ness&Prnf • Book Reviews Handbook of Digital IC Applications by David L. Heiserman Prentice-Hall Inc. Englewood Cliffs, NJ 1980, 428 pages, $21.95 Reviewed by Clifford R. Mosley Network Test and Training Facility Building 25, Code 850.2 Goddard Space Flight Center Greenbelt, MD 2077! Ordering a book without first reading the fine print is a risky thing to do. I have found that getting what you order is not always the same as getting what you want. When I first saw the title of this book, I thought, natural- ly enough, "This is a book full of digital IC application projects." Because I'm always anxious to build new gadgets, I promptly ordered the book. When it arrived, I tore open the package, flipped open the book, and found myself totally let down! It was not a collection of projects, but a book about basic digital con- cepts and devices. But I had paid good money for the book, and the least I could do was give it a closer TXL Telecommunications package to interface most mic- rocomputers to the Western Union Telex It (TWX) net- work. TXL allows your computer to function as an intelligent telex station — replacing the conventional paper tape telex machine. You edit your telex mes- sages to perfection using your text editor. TXL auto- matically formats and sends them. Incoming telex messages are received, displayed, stamped with date and time, and then written to disk storage. TXL outperforms the conventional paper-tape telex machine! TXL: Tetex Link is available in two hardware software packages: TXL: S-100 and TXL: RS 232. Both packages require Z-80 cpu and CP M. TXL: Telex Link: links your computer to the world of Telex communications Trademarks: Z-80 ■ Z1LOG. CP M - Digital Research. TXL Telex Link ■ Cawthon Scientific Group Cawthon Scientific Group 24224 Michigan Avenue Dearborn, Michigan 48124 Phone: 313-565-4000 Telex: 810-221-1265 Cawthon Drbn. look. When I overcame my initial prejudice, I discovered that it did, in fact, have some very good characteristics. Handbook of Digital IC Applications appears to have been primarily designed as a textbook for a technical school or intermediate engi- neering course in digital de- sign. At the end of each seg- ment, Heiserman has in- cluded an exercise on key points to encourage further study. Answers to selected exercises are included in the back of the book, allowing readers to check the accuracy of their quiz answers. Despite the fact that the book is targeted for a technical au- dience, I feel that a serious hobbyist with a fair math background could learn a great deal. The text is sup- ported by many helpful il- lustrations and is written in a pleasantly explicit style. Basic combinational logic (AND, OR, INVERT, etc.) and Boolean algebra are the dominant subjects of the be- ginning chapters of the book. These fundamentals are dis- cussed in a little greater detail than in most books of this type. Heiserman then moves into a discussion of digital hardware, detailing the de- sign aspects of interfacing TTL (transistor-transistor logic) and CMOS (comple- mentary metal-oxide semi- conductor) logic with some of the more common input and output devices. He also discusses some of the prob- lems encountered when com- bining TTL and CMOS logic within the same system and describes flip-flops, counters, timers, code converters, dis- play drivers, AOI (AND-OR- INVERT) circuits, and other similar digital devices. In the final chapters, Heiserman introduces more complex devices such as data selectors, data multiplexers/ demultiplexers, parity gene- rators/detectors, arithmetic circuits, and memory cir- cuits. One of the greatest strengths of the book is Chapter 11, where Heiserman uses a refreshing approach to present an application of the basic theory of the earlier chapters. He leads the reader through the design of a sim- ple digital measuring system (in this case a frequency counter), developing each unit of the system as a sepa- rate block, then illustrating the process of integrating all of the blocks into a complete system. The book has some weak points. It lacks a glossary, and the index is a little skim- py. Both are important in a technical book in order to quickly locate information. These faults reduce the over- all effectiveness of the book as a learning aid. Also, some minor technical (or possibly editing) errors tend to confuse the reader. One example can be found in the first chapter, where the typical power consumption of a CMOS gate is listed at 10 ns (nanoseconds). As it is standard practice to measure power consumption in units of watts, I assume that Heiserman intended the text to read 10 nw (nanowatts). Conclusion Handbook of Digital IC Applications is well written and superbly illustrated and would make an adequate digital-design textbook or tutorial for a serious hobby- ist. Although it wasn't the book I thought I had ordered, I am nevertheless pleased to have it as a part of my refer- ence library. ■ 240 April 1982 © BYTE Publications Inc 1982 NATIONAL COMPUTER CONFERENCE JUNE 7-10 • ASTRODOMAIN • HOUSTON, TEXAS ADVANCING PROFESSIONALISM Dramatic strides have been made in computer technology, and at NCC '82, you'll have a unique opportunity to learn about them. Eighty technical sessions will highlight nine specialized areas, and plenaries will feature four of this country's most distinguished speakers. You'll also see the most impressive display of modern computer technology in the world. More than 650 companies in some 3,200 exhibit booth units will provide you with a panorama of the industry's newest products and services! And the 17 Professional Development Seminars, constituting a conference within a conference, will probe five subject tracts of vital interest to you. So, call 800-556-6882 today to pre-register with a major credit card. You'll save time and money, and you can get help with your airline reservations as well. Then, attend the 1982 National Computer Conference and advance your professionalism. CALL 800-556-6882 Monday— Thursday 9:00 am to 8:00 pm [EST) Friday, 9:00 am until 6:00 pm In Rhode Island and outside the continental U.S., call 401-884-9500. Sponsored by: American Federation of Information Processing Societies, Inc.; Association for Computing Machinery; Data Processing Management Association, IEEE Computer Society; Society for Computer Simulation. Designing the Star User Interface The Star user interface adheres rigorously to a small set of principles designed to make the system seem friendly by simplifying the human-machine interface. In April 1981, Xerox announced the 8010 Star Information System, a new personal computer designed for offices. Consisting of a processor, a large display, a keyboard, and a cursor-control device (see photo 1), it is intended for business professionals who handle information. Star is a multifunction system com- bining document creation, data pro- cessing, and electronic filing, mailing, and printing. Document creation in- cludes text editing and formatting, graphics editing, mathematical for- mula editing, and page layout. Data processing deals with homogeneous, relational databases that can be sorted, filtered, and formatted under user control. Filing is an example of a network service utilizing the Ethernet local-area network (see references 9 and 13). Files may be stored on a work station's disk, on a file server on About the Authors These five Xerox employees have worked on the Star user interface project for the past five years. Their academic backgrounds are in com- puter science and psychology . Dr. David Canfield Smith, Charles Irby, Ralph Kimball, and Bill Verplank Xerox Corporation 3333 Coyote Hill Rd. Palo Alto, CA 94304 Eric Harslem Xerox Corporation El Segundo, CA 90245 the work station's network, or on a file server on a different network. Mailing permits users of work sta- tions to communicate with one another. Printing utilizes laser-driven raster printers capable of printing both text and graphics. As Jonathan Seybold has written, "This is a very different product: Dif- ferent because it truly bridges word processing and typesetting functions; different because it has a broader range of capabilities than anything which has preceded it; and different because it introduces to the commer- cial market radically new concepts in human engineering/' (See reference 15.) The Star user interface adheres rigorously to a small set of design principles. These principles make the system seem familiar and friendly, simplify the human-machine interac- tion, unify the nearly two dozen func- tional areas of Star, and allow user experience in one area to apply in others. In reference 17, we presented an overview of the features in Star. Here, we describe the principles behind those features and illustrate the principles with examples. This discussion is addressed to the designers of other computer pro- grams and systems— large and small. Star Architecture Before describing Star's user inter- face, several essential aspects of the Star architecture should be pointed out. Without these elements, it would have been impossible to design an interface anything like the present one. The Star hardware was modeled after the experimental Xerox Alto computer (see reference 19). Like Alto, Star consists of a Xerox- developed, high-bandwidth, MSI (medium-scale integration) processor; local disk storage; a bit-mapped display screen having a 72-dots-per- inch resolution; a pointing device called the "mouse"; and a connection to the Ethernet network. Stars are higher-performance machines than Altos, being about three times as fast, having 512K bytes of main memory (versus 256K bytes on most Altos), 10 242 April 1982 © BYTE Publications Inc Pric Performance Reliability CMC IS MEETING TODAY'S HIGH STANDARD OF EXCELLENCE WITH TOSHIBA, CMC'S OWN SUPERFIVE AND SUPERTEN, 5- AND 10-MBYTE MICROCOMPUTERS, AND OTHER FINE PRODUCTS TOSHIBA DESKTOP COMPUTERS CMC International offers dealers the new Toshiba computer line, CP/M® -based micros with lots of flexibility... your choice of one or two drives, either 5 v* or 8 inch. Toshiba computers come with C/PM, Microsoft BasicSO and CBasic* . We're proud to offer a system with day-in, day-out dependability, backed by one of the world's largest electronics manufacturers. And, we offer a com- prehensive dealer program including parts and module inventory, and prepaid freight for warranty repairs (if you ever need it). ALSO DISTRIBUTING: •Corvus »Tandon •Cltoh •NEC •Seagate •MicroPro •Dysan »MPI •Accounting Plus •Epson •Superbrain •Peachtree •Verbatim •Compustar •dBase II YOUR STOCKING DISTRIBUTOR (Vn A Division of Computer Marketing Corporation 64k RAM, 80x24 12" green 1-200 phosphor screen, complete with CP/M, MBasic80 and CBasic. Model 3 Nodtl 2 One 5 1 /4"280k Two 5Y*" 280k Disk Drive Disk Drives List '3700 List $ 4500 T- 64k RAM, 80x24 12" screen, 250 complete with CP/M, MBasic80 and CBasic. Model 3 One 8" 1 mbyte Disk Drive List '4750 Model 2 Two 8" 1m byte Disk Drives List '5750 CMC EXCELLENT DEALER DISCOUNTS To Order Call Toll Free 1-800-420-2963 11058 Main, Suite 125 Beilevue, WA 98004 PHONE (206) 453-9777 TELEX: 152 556 SEATAC Circle 452 on inquiry card Circle 26 on inquiry card. DON'T PAY MORE !!! TRS-80 MODEL III MODEL III WITH 2 DISK DRIVES (48K RAM) $1749.85 MODEL lit WITH 1 DISK DRIVE (48KRAM) .S14M.95 MODEL HI WITH 48K MEMORY (EXTENDEDBASIC). ..$849.95 MODEL III WITH 16K MEMORY (EXTENDEDBASIC). .. $825,00 DISK DRIVES FOR TRS-80 S MODEL 111 40 Track 40 Track Dual Sided 80 Track 80 T rack Dual Sided DRIVE0 $595 $729.95 $729.95 40 Track 40 Track Dual Sided 80 Track 80 Track Dual Sided DRIVE 2 DRIVE 3 EXTERNAL EXTERNAL $389 95 $369 95 $369 95 MODEL I $49995 $49995 $259.95 40TRACK TEAC OR TANDON DISK DRIVES WITH POWER SUPPLY AND CABINET Color Computer Disk Drives By Radio Shack.. $470 AW...WHAT THE HECK RAM Memory Chips for the TRS-80 Apple O C."l, c A Rnnrit; (Aualnn Hilll £17.99 IITie TOT Ti Ti & Q IS Ti 15 Q 13 Ti IS ia is Q IS IS IS l! Ti li B 19 li Ti IS 0i NEW Computer Stocks & Bonds (Avalon Hill) Star Blazer (Broderbund) Tax Beater (Datamost) REAP (Datamost) Time Manager (Microsoft) Foosball (Sinus) Twerps (Sinus) Snake Byte (Sinus) Audex (Sinus) Photar (Softape) Auto Atlas (CPU) Worm Hole (DakinS) Electric Duet (Insoft) CalcStar (Micro Pro) Wordstar Training Guide (book) Marauder (On-Line) Sherwood Forest (Phoenix) Zoom Grafix (Phoenix) The Queen of Phobos (Phoenix) .■'... GBS (Quality) Compucube (Stoneware) DB Utility #2 (Stoneware) DB Master Stat. (Stoneware) Planetary Guide (Synergistic) Atlantis (Synergistic) Soft Seventy (Synergistic) Castles of Darkness (Logical Choice) Ceiling Zero (Turnkey) The Gauntlet (Turnkey) Survival Adv. (USA) Apple Sptce (Adv. Inter.) $11.99 $18.69 $116.89 $116.89 $134.99 $26.99 $26.99 $26.99 $26.99 $26.99 $42.69 $26.99 $26.99 $119.99 $17.99 $30.99 $39.99 $36.99 $30.99 $S99.00 $26.99 $84.99 $84.99 $30.99 $36.99 $44.99 $30.99 $26.99 $26.99 $21.99 $26.99 #4801 #4804 #4805 #4810 #3257 #3255 #3250 #3251 #3252 #3253 #3254 #3256 #7360 #7367 #7362 #7368 #7364 #7365 #2253 #2254 #2262 #2259 #2263 #2260 #2264 #2261 #1120 #1104 #1126 #1119 #1128 #1109 #1103 #1123 #1129 #1125 #1113 #1111 #1149 #1121 # 1 1 24 #1122 #1127 #1112 #1100 #1068 #1065 #1067 #1062 #1061 #1069 #1070 #1055 # 1 056 AURORA Executive Secretary Hebrew II Quicktrace Versacalc3.3 BEAGLE BROS. Alpha Plot Doss Boss 3.2 Doss Boss 3.3 Game Pack #1 Game Pack #2 Game Pack #3 Game Pack #4 Utility City CONDUIT Algebra Drill & Practice I Demo-Graphics Group Velocity SAMP - Survey Sample Satellite Orbits Scatter - Nuclear Scatter MICRO LAB Crown of Arthain Madventure Merger Palace in Thunderland Roach Hotel SAT-English 1 Tax Manager U.S. Constitution ON-LINE Cranston Manor Crossfire The Dictionary Expediter II Compiler General Manager Hi-Res Cnbbage Jaw Breaker Lisa Lisa Educational Pkg MMSII Missile Defense Mouskattack Pegasus II Soft Porn Adventure Speed ASM Threshold Time Zone Ulysses The Wizard & the Princess SIRIUS Beer Run Cops & Robbers Dark Forest Epoch Gorgon Hadron Joyport Phantoms Five Space Eggs $212.50 $30.99 $43.99 $84.99 $34.69 $20.39 $20.39 $20.39 $20.39 $20.39 $20.39 $23.89 $125.99 $91.19 $10.19 $34.89 $34.89 $29.69 $21.19 $42.29 $21.19 $30.69 $25.49 $131.99 $23.49 $29.69 $26.29 $81.89 $87.89 $21.19 $26.29 $67.89 $103.49 $43.89 $25.39 $35.09 $25.39 $23.39 $33.89 $33.89 $87.89 $29.69 $28.89 $26.29 $29.69 $26.29 $29.69 $33.89 $30.69 $67.39 $33.39 $25.39 By Fred Huntington Time for our latest new program for the Apple". Computer Almanac. Written by David Carman, an honest-to-goodness weatherman, Computer Almanac is a diverse collection of well thought-out programs. It contains sunrise and sunset times, weather forecasts for any year, a wind chill chart, light- ning safety rules, a super-duper extra easy to use loan amoritization program that will print out in 80 columns, health chapter (including a nifty calorie counter), a vacation planner, a biorythm chapter (needs printer) and more. We're very proud of this program and think that at $24.95, it's one of the best bargains in the software market today. Also, don't forget our other new program for the Apple \ Understand Yourself, also $24.95. Dealer inquiries welcome. Speaking of good programs, we'd like to recommend for either home or school use Crossword Magic by L&S Computerware. A super outstanding program with nothing else even close, we thought the original price of $79.95 was a little steep. So we were able to convince them to lower it to $49.95, which is still a little steep for a crossword program, no matter how fantastic. So, to prove a point, we've set the price at $39.99. Now it's a bargain. It will work with most graphic printers, inc- luding the Epson, with or without the Grappler. GREAT GRANDMA HUNTINGTON Great Grandma Huntington told me when I was a lad that I should always buy my compu- ter media as a diskcount. She also said that a single density disk in the hand was better than a double density disk in the bush. Great Grandma Huntington said a lot of things, many of which I can't remember. So we're having a contest to see who can come up with the best Great Grandma Huntington sayings. Ail entries must be postmarked no later than June 30, 1982 and should be ad- dressed to: GREAT GRANDMA HUNTINGTON CONTEST P. O. Box 787 Corcoran, CA 93212 The top two entries will receive genuine Epson LC Digital Quartz watches (yep, made by the same people who make those great printers). Winners will be used in future Soft- lights columns. All entries become the prop- erty of Huntington Computing and will not be returned. The worst ones may be used in future advertising: DISKS Elephant Disks 10/24.99 Verbatim 10/28.99 (with plastic box) Maxell .10/36.99 #6761 #6758 #6759 #6760 #7555 #7552 #7554 #7550 #7561 #7560 #1014 #1012 #1002 #1016 #1015 #1007 #2651 #6100 #3350 #5780 #3700 #6707 #5453 #2008 #3200 #3702 #6101 #2752 #4401 #2294 #3452 #4750 #218 #2290 #2059 #22 #1408 #4250 #6080 #7401 #5920 #1476 #2210 #4300 #6102 #3391 #7975 #2058 #5800 #5805 #2400 #2402 #2403 #1804 #1816 #2211 #90 #3300 #3301 #6240 #6709 #7100 #6710 #7970 #1900 #4701 #2355 #7008 #3400 #2751 #91 #1150 #1403 #7006 #2701 #7101 #3701 #4251 #3482 #1020 #3511 #2061 #2750 #7102 #5900 #2804 #4700 #3461 #4350 #18 #2655 PENDULUM PRESS 20,000 Leagues Under The Sea Time Machine Tom Sawyer Treasure Island $29.69 $39.69 $39.69 $29.69 $25.39 $25.39 $42.29 $42.49 $17.49 $17.49 $33.89 $33.89 $35.99 $52,69 $33.89 $33.89 Call TOM-Free 800-344-5106 (outside California) Post Office Box 1297 Corcoran, California 93212 Ti M Foreign Orders ^ In California I 209-992-4481 800-692-4146 TRS Atari COMPUTING IS Ti IS Ti U Ti i3 Ti Ti Ti Ti IS Ti Ti Ti Ti Ti Ti Ti Ti Ti SPECTRUM Action Adventure Game Series Color Calendar Home Finance Pak I Microaccountant Numerical Analysis Statistical Analysis I STRATEGIC SIMULATIONS Battle Of Shiloh Computer Baseball Computer Quarterback Napoleon's Campaign Tigers In The Snow The Warpfactor MISCELLANEOUS Apple Doc (Southwestern) $43.99 Apple Grade Book (J&S) $26.49 Apple Letter Perfect (LJK) $127.49 Apple Word Processing (book) (Que) $17.49 Asteroid Field (Cavalier) $22.49 Astronomy I (Ed. Courseware) $28.89 Basic Scientific Sub-Routines Vol II (book) . $21.87 Beneath Apple Manor (Quality) $17.49 Brain Surgeon (Nikrom) $42.39 Bug Attack (Cavalier) $26.29 Computer Chemistry (J&S) $139.99 Creative Finance (Howardsoft) $127.49 Cyborg (Sentient) $28,99 Datadex (IUS) $238.69 Decision Master (Syntonic) $33.89 Disk Prep (Sympathetic) $21.19 Dosource 3.3 (Lazer) $33.89 Easy Writer Pro (IUS) $219.88 Empire of the Overmind (Avalon Hill) $29.69 Enhancer II (Videx) $131.89 Escape (Subtogic) $26.29 Falcons (Piccadilly) $23.39 Firebird (Gebelli) $33.39 Fractions Concepts & Operations $36.99 Free Lance Software Marketing Kern (book) $26.46 Game Paddles (TG) $33.89 Goblins (Highland) $23.29 GRAN PRIX (Riverbank) $23.39 Hi-res Chemistry (J&S) $197.99 Mastertype (Zwieg) $35.89 investment Decisions (Mesa Research) . $84.99 Major League Baseball (Avalon Hill) ...-..., $23-49 Micro Apple I (Micro Ink) $21.19 Micro Apple II (Micro Ink) $21.19 Micropainter (Datasoft) $31.99 Micropamter Refill # 1 (Datasoft) $16.89 Micropainter Refill #2 (Datasoft) $16.89 Monty Plays Monopoly (Personal) $31.99 Monty Plays Scrabble (Personal) $33.89 Mummy's Curse (Highland) $26.39 Music System (Mountain) $349.88 PFS (Software) $88.69 PFS-Report (Software) $87.49 Paddle- Adapple (So. Calif. Research) $26.89 Physics I - Free Fall (Ed. Courseware) $28.89 Pool 1.5(1DSI) $29.69 Population (Ed. Courseware) $21.89 Portfolio Master (Investors Software) $63.69 Prisoner (Edu-Ware) $26.95 Pro Football (SDL) $44.89 Programmers Handbook (Comp. Sta.) $36.96 Race for Midnight (Avant Gard) $23.39 Raster Blaster (Budge Co) $23.39 Real Estate Analyzer (Howardsoft) $127.49 Romwriter (Mountain) $148.69 Sargon II (Hayden) $29.69 Saturn Navigator (Sublogtc) $21.19 Sentence Diagramming (Avant Gard) $21.19 Sexoscope(AGS) $26.99 Shuffleboard (IDS!) $23.39 Star Thief (Cavalier) $25.39 Suicide (Piccadilly) $26.29 Super Sound (Rainbow) $14.39 SuperCalc (Sorcim) $230.69 Tablet Shape Maker (Rocky Mountain) $84.09 Tanktics (Avalon Hill) $24.39 Tax Preparer '82 (Howardsoft) $131.99 Trickshot (IDSI) $33.09 Using 6502 Assembly Lang, (bk) Datamost . $16.89 Valdez (Dynacomp) $16.89 Win At The Races (SDL) $44.89 Wizardry (Sir Tech) $42.39 Word Star (Micro Pro) $289.00 Z Card (ALS) $239.00 Z-Term (Southwestern) $84.99 riNC We take MasterCard, American Express or VISA (Include card # and Apple - is a registered trademark of Apple Computer, inc. expiration date). California residents add 6% tax. Include $2.00 for postage. Pet- ts a registered trademark of Commodore. Foreign and hardware extra. Foreign (excluding Canada): remit U.S. cur- se is a registered trademark of Tandy Corp. rency, checks on U.S. banks, use listed charge cards, or make direct wire - is a registered trademark of Atan, inc. transfers through Security Pacific Bank, Corcoran, for a $6.00 charge. All Outside Calif, 800-344-5106 overseas orders shipped by air. Send for free catalog. Prices subject to change without notice Circle 197 on inquiry card. BYTE April 1982 253 Figure 1: In~hasket and out-basket icons. The in-basket contains an envelope indicating that mail has been received. (This figure was taken directly from the Star screen. Therefore, the text appears at screen resolution.) TtifieupyourLA36 • RS232 interface • 20 mA Current Loop interface • Top of Form • Adjustable Margins • Double wide characters • Parity selection • Optional APL character set The DS120 Terminal Controller makes your LA36 perform like a DECwriter® III. The Datasouth DS120 gives your DECwriter® II the high speed printing and versatile performance features of the DECwriter® III at only a frac- tion of the cost. The DS120 is a plug compatible replacement for your LA36 logic board which can be installed in minutes. Standard features include: • 165 cps bidirectional printing • Horizontal & Vertical Tabs • Page Length Selection • 110-4800 baud operation • 1000 character print buffer • X-on, X-off protocol • Self Test Over 5,000 DS120 units are now being used by customers ranging from the Fortune 500 to personal computing enthusiasts. In numerous instal- lations, entire networks of terminals have been upgraded to take advan- tage of today's higher speed data communications services. LSI microprocessor electronics and strict quality control en- sure dependable performance for years to come. When ser- vice is required, we will respond promptly and effec- tively. Best of all, we can de- liver immediately through our nationwide network of distributors. Just give us a call for all the details. data computer corporation 4740 Dwight Evans Road • Charlotte, North Carolina 28210 • 704/523-8500 when designing a system is that the approach adopted changes the func- tionality of the system. An example is electronic mail. Most electronic-mail systems draw a distinction between messages and files to be sent to other people. Typically, one program sends messages and a different program handles file transfers, each with its own interface. But we observed that offices make no such distinction. Everything arrives through the mail, from one-page memos to books and reports, from intraoffice mail to inter- national mail. Therefore, this became part of Star's physical-office metaphor. Star users mail documents of any size, from one page to many pages. Messages are short documents, just as in the real world. User actions are the same whether the recipients are in the next office or in another country. A physical metaphor can simplify and clarify a system. In addition to eliminating the artificial distinctions of traditional computers, it can eliminate commands by taking ad- vantage of more general concepts. For example, since moving a docu- ment on the screen is the equivalent of picking up a piece of paper and walking somewhere with it, there is no "send mail" command. You sim- ply move it to a picture of an out- basket. Nor is there a "receive mail" command. New mail appears in the in-basket as it is received. When new mail is waiting, an envelope appears in the picture of the in-basket (see figure 1). This is a simple, familiar, nontechnical approach to computer mail. And it's easy once the physical- office metaphor is adopted! While we want an analogy with the physical world for familiarity, we don't want to limit ourselves to its capabilities. One of the raisons d'etre for Star is that physical objects do not provide people with enough power to manage the increasing complexity of the "information age." For example, we can take advantage of the com- puter's ability to search rapidly by providing a search function for its electronic file drawers, thus helping to solve the long-standing problem of lost files. 254 April 1982 © BYTE Publications Inc Circle 139 on inquiry card. IT'S CRISP. IT'S CLEAR, IT'S COMPATIBLE. Amdek's Video-300 green phosphor monitor is the easy-reading choice for almost any system— including IBM and Apple. 1 8MHz band width 900 lines [center) resolution Everything about our 12" Video-300 monitor was designed to be easy. Easy to read. Easy to use. And easy to match up with practically any computer or word processing system, including the popular Apple and IBM personal com- puters. So it's easy to see why you should choose Video-300 for your text display needs. Amdek's Video-300 monitor features: • Non-glare screen to eliminate dis- tracting reflections • P-31 green phosphor display for no-strain viewing • 80 x 24 character display • Built-in carrying handle for porta- bility • Light-weight, industrial-grade cabine- try Conly 17 lbs.) • UL, FCC approved • Full one-year warranty covering parts and labor So ask your dealer about Video-300 — part of Amdek's complete line of color, green phosphor and black and white monitors. Then match Video- 300's performance and price against any other display monitor For quality and value, you'll choose Amdek. Amdek Corporation, 2420 E. Oakton St., Suite E, Arlington Heights, IL 60005. (312) 3G4-1180 • TLX: 25-4786 Circle 24 on inquiry card. BYTE April 1982 255 The "Desktop" Every user's initial view of Star is the "Desktop/' which resembles the top of an office desk, together with surrounding furniture and equip- ment. It represents your working en- vironment — where your current proj- ects and accessible resources reside. On the screen are displayed pictures of familiar office objects, such as documents, folders, file drawers, in- baskets, and out-baskets. These ob- jects are displayed as small pictures or 'Icons/' as shown in figure 2. You can "open" an icon to deal with what it represents. This enables you to read documents, inspect the contents of folders and file drawers, see what mail you have received, etc. When opened, an icon expands into a larger form called a "window," which displays the icon's contents. Win- dows are the principal mechanism for displaying and manipulating infor- mation. The Desktop "surface" is displayed as a distinctive gray pattern. This restful design makes the icons and windows on it stand out crisply, minimizing eyestrain. The surface is organized as an array of one-inch squares, 14 wide by 11 high. An icon can be placed in any square, giving a maximum of 154 icons. Star centers an icon in its square, making it easy to line up icons neatly. The Desktop always occupies the entire display screen; even when windows appear on the screen, the Desktop continues to exist "beneath" them. The Desktop is the principal Star technique for realizing the physical- office metaphor. The icons on it are visible, concrete embodiments of the corresponding physical objects. Star users are encouraged to think of the objects on the Desktop in physical terms. Therefore, you can move the icons around to arrange your Desktop as you wish. (Messy Desktops are certainly possible, just as in real life.) Two icons cannot oc- cupy the same space (a basic law of physics). Although moving a docu- ment to a Desktop resource such as a printer involves transferring the document icon to the same square as the printer icon, the printer im- mediately "absorbs" the document, queuing it for printing. You can leave QQE XEROX STAR User-lnterfacei DOCUMENT OBJECTS Page Text character paragraph "■--.. Frame Graphics . line symbol chart Tafete Equation Te,t Field Footnote Record File Folder ■% L a D ""• □D □ id Out-Ba^.ets Floppy Cm ;1 Dr User and User Calculator terminal Emu Cheel er Director.- Mi m it KEYBOARD Select Adjust UNIVERSAL COMMANDS Delete Copy Move ' Show Properties Copy Prop ertie; Again Undo Help 3[_2lla5<3 M BBS Sales February ; rile.; Figure 2: A Desktop as it appears on the Star screen. Several commonly used icons appear across the top of the screen, including documents to serve as "form-pad" sources for letters, memos, and blank paper. An open window displaying a document containing an illustration is also shown. 256 April 1982 © BYTE Publications Inc The revolutionary Discovery multiprocessor is the only system that allows the total integration of powerful 16 bit 8086 processors with the more standard Z-80 user processors. The DISCOVERY system may be configured in any 8 bit/16 bit combination, or as a totally exclusive 16 bit system only to provide the ultimate in performance and flexibility in advanced micro systems. Ultimate performance. The dpc-186 is the most sophisticated single board microcomputer available today offering more power and faster processing time through the 8086 CPU for bigger, more complex programs. Memory starts at 128 K (compared to the Z-80's 64 K), and is expandable to 1 megabyte, And the dpc-186 is fully compatible with the standard DISCOVERY multiprocessor system permitting efficient upgrading as future needs develop, without sacrificing any of your extensive hardware and software investment. World's best multiprocessor system. The DISCOVERY system pro- vides separate processors and memory for each of its 16 users, It offers full CP/M^and CP/M-86™ compatibility, interprocessor communication, and shared and private files, Each user can take advantage of shared peripherals and cross submitting of tasks between processors, The system is controlled by a unique, two board dpc-280 service processor and dpc/os distributed processing operating system. By the board or by the system. The DISCOVERY multiprocessor is ready for immediate delivery as a complete system, as processor boards, and everything in between. It offers exclusive technology in multipro- cessing, yet is fully compatible with existing standards including CP/M and S-100. It is quite simply unmatched in performance, capabilities and offers a far greater degree of flexibility. DISCOVERY— offering a whole new world of possibilities. time, 8 and 16 bit processor intermixing. Action Computer Enterprises, Inc. KT^ The Multiprocessing Company 55 West Del Mar Boulevard, Pasadena, CA 91105 USA k^ ^k. ] ( 213 ) 793-2440, TWX 910-588-1201 Circle 9 on inquiry card. Dealer and OEM inquiries invited. *CP/M is a registered TM of Digital Research, Inc. We Were Here Yesterday... We Will Be Here Tomorrow With Support & Service For You! SUPRBRAIN 64k D/D 64k QD $ 2565 $ 2945 NORTHSTAR HORIZON II LIST $4195 64k QD $ 3275 ADVANTAGES 125 HARD DISKS 5mb for IBM, Superbrain. S-100, Zenith, TRS-80 It & III, Xerox, Apple. $ 2795 CORVUS Call For Prices 5V 4 " DISK DRIVES TANDON S/S D/D mtktkm IBM COMPATIBLE '225 TANDON D/SD/D $ 350 TANDON 100-4 80 track. ...'600 SUPERBRAIN ADD-ON S/S, D/D w/power supply, cable, case, software, one drive. $ 365 TERMINALS Many brands available. Call for prices. COMET II.-..WJJT?!? $796 EPSON MX80 parallel $479 EPSON MX100 $740 Cltoh F10 40 cps parallel * $1550 NEC 7710, 7730 • $2395 NEC 3510 rs232 * $1895 DATA SOUTH isocps $1355 OKIDATA 82A $530 MPI 88G 120 cps $550 MPI 99G L.C. decenders $650 • Tractors Available $220 * DISKETTES DYSAN 5V4" S/S, D/D $ 34.70 BOX OF 10 • SUPERBRAIN S-100 Bus Adapter LIST $595 SUPERBRAIN Parallel Port SBE Prom $ 475 LIST $90 »75 LIST $205 '155 SOFTWARE C Basic II 'IB M Basic 80 '275 MT Pascal '430 Fortran 80 '450 Cobol 80 '660 M Basic Compiler. . *329 ACCT. Plus '306 Word Star ;.., '306 Supercalc '266 D-Base II *600 GRAPHICS For SUPERBRAIN Graphics Board "806 Symbol Generator. . .'200 Graphics Plotter '200 3-D Graphics. ... .'400 Surface Plotter '460 Graphics Terminal Emulator '450 Toil-Free Ordering 1-800-426-2662 For Information CalT(206) 453-8159 Mail and telephone orders only. Mastercharge, VISA add 3%. COD Certified check under $1000. All prices FOB origin. Send for catalog. Mail all correspondence to P.O. Box 3952, Bellevue, WA 98009 PACIFIC COMPUTER BROKERS P.O. Box 3952, Bellevue, WA 98009 documents on your Desktop in- definitely, just as on a real desk, or you can file them away in folders or file drawers. Our intention and hope is that users will intuit things to do with icons, and that those things will indeed be part of the system. This will happen if: (a) Star models the real world ac- curately enough. Its similarity with the office environment preserves your familiar way of working and your ex- isting concepts and knowledge. (b) Sufficient uniformity is in the system. Star's principles and "generic" commands (discussed below) are applied throughout the system, allowing lessons learned in one area to apply to others. The model of a physical office pro- vides a simple base from which learn- ing can proceed in an incremental fashion. You are not exposed to entirely new concepts all at once. Much of your existing knowledge is embedded in the base. In a functionally rich system, it is probably not possible to represent everything in terms of a single model. There may need to be more than one model. For example, Star's records- processing facility cannot use the physical-office model because physical offices have no "records pro- cessing" worthy of the name. Therefore, we invented a different model, a record file as a collection of fields. A record can be displayed as a row in a table or as filled-in fields in a form. Querying is accomplished by filling in a blank example of a record with predicates describing the desired values, which is philosophically similar to Zloof's "Query-by- Example" (see reference 21). Of course, the number of different user models in a system must be kept to a minimum. And they should not overlap; a new model should be in- troduced only when an existing one does not cover the situation. Seeing and Pointing A well-designed system makes everything relevant to a task visible on the screen. It doesn't hide things under CODE + key combinations or 258 April 1982 © BYTE Publications Inc Circle 318 on inquiry card. Systems H€x a total business system. JOB COSTING MENU 1. TRANSACTION ENTRY/DATE 2. JOB/TASK TABLE MAINTENANCE 3. JOB COST FILE MAINTENANCE 4. JOB COST REPORTING 5. EMPLOYEE TABLE MAINTENANCE 6. RETURN TO MASTER MENU SELECT (1-6|? SYSTEMS II EX MASTER MENU 1. INVENTORY 7. CHART OFACCTS. i 2. PAYABLES 8. VENDOR MAINT. 3. RECEIVABLES 9. CUST. MAINT. I 4. PAYROLL 10. CHANGE OATE 5. LEDGER 11.SYS./BACKUP 6. JOURNAL 12.ST0P PROCSSG. 13. OPTIONAL PROCSSG. L. SELECT 11-13)? DATABASE MENU 1. FILE MAINTENANCE 2. REPORTS/REPORT MAINT. 3. UTILITIES 4. RETURN TO SYSTEM MENU SELECT |141? ACCOUNTS PAYABLES MENU 1. FILE MAINTENANCE 2. PAYMENT SELECTION 3. PRINT CHECKS AND REGISTER 4. MONTH END 5. RETURN TO MASTER MENU SELECT (1-5)? RECEIVABLES SYSTEM MENU 1. FILE MAINTENANCE 2. RECEIPT OF PAYMENTS 3. GENERATE BILLING 4. MONTH END 5. PAST DUE REPORT 7. RETURN TO MASTER MENU . SELECT (1-7)? LEDGER SYSTEM MENU 1. FILE MAINTENANCE 2. BAL SHEET/INCOME STATEMENT , 3. YEAR END PROCESS [ 4. RETURN TO MASTER MENU SELECT |14)? INVENTORY SYSTEM MENU TIME DATE 1. FILE MAINTENANCE 2. POINT OF SALES 3. REORDER REPORT 1 4. RETURN TO MASTER MENU I SELECT (14)? STATE PAYROLL MENU 1. MISC/TAX TABLE MAINT. 2. TRANSACTION FILE 3. MISC. PAY/DEDUCTION FILE 4. EMPLOYEE MASTER FILE 5. CALCULATE/PRINT CHECKS 6 PRINT W2'$ 7. RETURN TO MASTER MENU SELECT 11-71? SYSTEMS II EX — EX for EXTENDED PERFORMANCE. Westware brings you the most completely integrated and simplest to use business software for your Apple Computer. The SYSTEMS II EX is complete with an integrated Database. Yes! The DBII Database can move your system's files into Database format for customized reports or labels. Although the SYSTEMS II EX is a fully integrated system, you may purchase individual modules and later add additional modules, such as Job Costing for contractors. The power of our system is in the KSAM Firmware card that plugs into the Apple. This card permits high speed searches and eliminates running sort routines to get your files in order. SYSTEMS II is available on 5%" drives, and also on the Corvus hard disk. A Corvus based system will give you the power and capacity that challenges larger computers. COMING SOON — Cash flow analysis with graphics, Database II with graphics, and Bill of Materials for small manufacturers. CURRENT OPTIONS AVAILABLE — Job Costing, Cycle Invoicing, Order entry, and Layaway. All Checks, statements and invoices use NEBS forms. Dealer and OEM inquiries invited. Apple is a trademark of Apple Computers. Systems]! €x 2455 S.W. 4th Ave. Suite 2 Ontario, OR 97914 (503) 881-1477 Circle 435 on inquiry card. Yes. please send 1 me your Systems II Demo Package. □ Yes, I would like to sample your software. Please send me the Systems II Demo Package. My check for $25 is enclosed. Name 2455 S.W. 4th Ave. Suite 2 Ontario, OR 97914 1(503) 881-1477 Title Company Name. Address City State -Zip_ force you to remember conventions. That burdens your memory. During conscious thought, the brain utilizes several levels of memory; the most important being the "short-term memory." Many studies have ana- lyzed the short-term memory and its role in thinking. Two conclusions stand out; (1) conscious thought deals with concepts in the short-term memory (see reference 1) and (2) the capacity of the short-term memory is limited (see reference 14). When everything being dealt with in a computer system is visible, the display screen relieves the load on the short-term memory by acting as a sort of 'Visual cache." Thinking becomes easier and more productive. A well- designed computer system can actual- ly improve the quality of your think- ing (see reference 16). In addition, visual communication is often more efficient than linear communication; a picture is worth a thousand words. A subtle thing happens when everything is visible: the display becomes reality. The user model becomes identical with what is on the screen. Objects can be understood purely in terms of their visible characteristics. Actions can be understood in terms of their effects on the screen. This lets users conduct ex- periments to test, verify, and expand their understanding — the essence of experimental science. In Star, we have tried to make the objects and actions in the system visi- ble. Everything to be dealt with and all commands and effects have a visi- ble representation on the display screen or on the keyboard. You never have to remember that, for example, CODE + Q does something in one context and something different in another context. In fact, our desire to eliminate this possibility led us to For The Best In Price, Selection and Delivery, Call Now TOLL FREE 800-368-3404 (In VA, Call Collect 703-327-8695) AMPEXHNTERTEOTEXAS INSTRUMENTS-GENERAL DATA COMM.*ANDERSONJACOBSON*C.ITOH*QUME • BEEHIVE* DATASOUTH*DIABLOCENTRONICS • NEC • PRENTICE riH.Mi INTERTEC: Superbrain QD $2995 Egcnsa DATASOUTH: $1235 NEC: 7710 $2196 7715 Call for Special Price 7730 $2196 7720 Call for Special Price 7725 Call for Special Price Std. Forms Tractor $ 200 Bi-Dir. Forms Tractor $ 300 CENTRONICS: 739-1 (Parallel) $ 649 739-3 (Serial) Call for Special Price QUME: Sprint 5, 55RO $2339 Sprint 5, 55KSR Call Sprint 9, 45RO, Limited Panei $1845 Full Panel $1969 Std. Forms Tractor $ 199 Bi-Dir. Forms Tractor $ 199 DIABLO: 630-R102RO $1995 TERMINALS AMPEX: Dialogue 30 $ 775 Dialogue 80 $ 939 BEEHIVE: (SMART DISPLAY) DM5 $ 745 DM5A $ 930 DM310 (3101 Emulator) . . .$1095 NOTE: IBM and Burroughs compatible ter- minals available. Please inquire. C. ITOH CIT101 $1350 TEXAS INSTRUMENTS: 745 Standard $1390 810 Basic $1249 810 Package $1439 820 Package RO Package .$1610 820 RSR Package Call 840 RO Basic $ 795 840 RO Tractor Feed Pkg. . $1 059 COUPLERS STAR: 300 Baud .$ 149 DISC DRIVES QUME: Data Trak 5 . . . $325 or 2 for $599 Data Trak 8 . . $549 or 2 for $1 049 SOFTWARE BISYNC-80RJE $ 769 Wordstar $ 319 Data Star $ 215 Cobol $ 789 Forms2(CobolGen.) . $ 179 Mail Merge $ 99 Spell Guard $ 229 Plan 80 $ 249 Super Calc $ 249 Milestone $ 249 Most items are in stock now. In addi- tion, we can make EIA RS232 or RS449 cables to your order, and supply you with ribbons, printer stands, print wheels, thimbles for all printers listed. And many, many more items. CALL NOW. Add 2% for shipping and insurance. Superbrain shipped frsight collect. VISA and MasterCards welcomed; add 3°/o for credit card purchases. Virginia residents, add 4% Sales Tax. For fastest delivery, send certified check, money order or bank-wire transfer. Sorry, no C.O.D. orders. All equipment is in factory cartons with manufac- turers' warranty. Prices subject to change without notice. hMW TCBfQIflflLS lilllfll Terminals Terrific, Incorporated, P.O. Box 490, Falls Church, VA 22046, 800-368-3404 (In VA, Call Collect 703-237-8695). 260 April 1982 © BYTE Publications Inc Circle 412 on inquiry card. "Wfe provide business programs as individual as your business needs." "Allow me to introduce myself. I'm a Vector computer, dedicated to the advancement of society. And I'd like to tell you how a computer can help you man- age your business more efficiently. Especially if that computer is a Vector, like me. Because we're prob- ably the most flexible and cost-effective computers you can find. "Our programs are the key. Because they enable me to handle sales forecasting, budgeting, job costing and proposals, commissions, personalized mass mail- ings, charts and graphs. We Vectors can even talk to each other and to other bigger computers. "Unique combinations of our individual pro- grams can actually customize me to meet your specific requirements. Any combination of our software pack- ages can be assembled right off the shelf, to help you realize your full potential as a salesman, merchant, stockbroker, clergyman, contractor, real estate or insur- ance agent or whatever your business. "Choose from Memorite III for word processing and mail list management, Execuplan for financial plan- ning and forecasting, Business Accounting, Data Management for filing and sorting information, Com- munications and a host of others. And, of course, all we Vectors come with the popular CP/M operating system. "For more information and your local dealer, call us at (805)499-5831 or (800) 235-3547. In California, call (800) 322-3577. Or write to us at 500 North Ventu Park Road, Thousand Oaks, CA 91320. "We'll show you how we small information systems can mean big business for you" Circle 424 on inquiry card. Vector Graphic, Inc. COMPUTERS FOR THE ADVANCEMENT OF SOCIETY. Sold and supported by 400 dealers worldwide. Vector Products are approved on General Services Administration authorized ADP scheduled price list. Circle 278 on inquiry card. MAR. SPECIAL SALE ON PREPAID ORDERS (CHARGE CARDS, C.O.D. OR PC'S NOT AVAILABLE) ME KM INTRODUCTORY SALE 65K STATIC RAM/ROM. OSES USES TMS 4016/TMM 2016 RAM OR 2716 EPROMS EXTENDED ADDRESSING. AVAILABLE END OF APRIL PCBD $35.95, KIT LESS MEMORY $89.95 A & T LESS MEMORY $129.95 € CALIFORNIA COMPUTER SYSTEMS $100 2032 32 K STATIC RAM A & T. 200 NSEC . . . .5629.00 2065 64K DYNAMIC RAM A & T $548.95 2200 S-100 MAIN FRAM A&T $379 95 2422 FLOPPY DISC WITH CP/M 2.2'" $329.95 2810A Z80 CPU A & T $249.95 2710A4 SERIAL 1/0 A&T. $291 95 2718A 2 SERIAL, 2 PARALLEL A&T, $305.95 2720A 4 PARALLEL A&T $214.95 PROTO BOARDS WW $39.95 APPLE PRODUCTS 7114A 12K ROM/PROM $68.50 7424A CALENDAR/CLOCK $106.95 7440A PROGRAMMABLE TIMER $98.50 7470A A TO CONVERTER $105.95 7490A GPIB (IE 488) INTERFACE $265.95 7710A ASYNC SERIAL $125.95 7712A SYNC SERIAL $153.95 7720A PARALLEL STANDARD $98.95 77208 PARALLEL CENTRONICS $98.95 78118 ARITHMETIC PROCESSOR W/DiSC. . . . $342.95 781 1C ARITHMETIC PROCESSOR W/ROM . . . $342.95 7500A WW BOARD $22,95 751DA SOLDERTAIL BOARD $23.95 JS59 MICROCOMPUTER PRODUCTS SI 00 PRODUCTS CB-2 280 PROCESSOR BOARO. KIT $198.95, A&T .$269.95 VBIC 64 x 16 VIDEO, PCBD $32.95 KIT $153.95, A&T $199 95 VB3 80 CHARACTER VIDEO 4MHZ KIT $345.95, A&T $425.95 104 2 PARALLEL, 2 SERIAL, PCBD $32.95 KIT $155.95, A&T $194.95 P8-1 2708, 2716 PROGRAMMER BOARD KIT $135.95, A&T $185 95 APPLE PRODUCTS AIO SERIAL/PARALLEL INTERFACE KIT $125.95, A&T S155 95 ASIO SERIAL I/O KIT $87.95, A&T $97.95 APIO PARALLEL IO W/O CABLES KIT $67.95 A&T $87.95 wmc tnC. WAMECO INC. BOARDS WITH MIKOS PARTS MEM-3 32K STATIC RAM, PCBD $36.95 KIT LESS RAM $95.95, A&T $135.95 CPU-2 Z80 PROCESSOR. PCBD $32.95 KIT LESS ROM $109.95. A&T $149,95 EPM-2 16K/32K EPROM, PCBD $32.95 KIT LESS ROM $65 95, A&T $99.95 FPB-1 FRONT PANEL, PCBD KIT $144.95, A&T QMB-12 13 SLOT MOTHER BOARD, PCBD. KIT $95.95, A&T . , $48.50 $184.95 , $39.95 $135.95 M MONDAY-FRIDAY, 8:00 TO 1 2:00, 1 :00 TO 5:30 THURSDAYS, 8:00 TO 9:00 P.M. (415) 728-9121 P.O. BOX 955 • EL GRANADA, CA 94018 PLEASE SEND FOR IC. XISTOR AND COMPUTER PARTS LIST VISA or MASTERCHARGE Send account number, interbank number, expiration date and sign your order Approx postage will be added Orders with check or money order will be sent post paid in U S If you are not a regular customer, please use charge, cashier's check or postal money order Otherwise there will be a two-week delay tor checks to cleaj Calif residents add 6% tax Money back 30-day guarantee We cannot accept returned iC's that have been soldered to Prices subject to change without notice $20.00 minimum ontir JZ 00 itrvice charge on orders lest thin $20.00. >■■.!. ili.l^ ■!■■*■ ih ■!■■*■ ill A i J CHARACTER PROPER TIE: (OlTone) (D^itTl EEE5E3 PARAGRAPH TAB SETTINGS Font Cfassk Titan Bold Letter-Gothic S ci e fit if ic I S c\ e nt i f i cT h i n X e Size |8|10|B14|18|24| Face '|:MW | ITALICS | "JNDEP.LINE | | STRIKEOUT] Position iix n Xq x xd xx°x X ox Xd OTHER. I Figure 3: The property sheet for text characters. abolish the CODE key. (We have yet to see a computer system with a CODE key that doesn't violate the principle of visibility.) You never in- voke a command or push a key and have nothing visible happen. At the very least, a message is posted ex- plaining that the command doesn't work in this context, or it is not im- plemented, or there is an error. It is disastrous to the user's model when you invoke an action and the system does nothing in response. We have seen people push a key several times in one system or another trying to get a response. They are not sure whether the system has "heard" them or not. Sometimes the system is simply throwing away their keystrokes. Sometimes it is just slow and is queu- ing the keystrokes; you can imagine the unpredictable behavior that is possible. We have already mentioned icons and windows as mechanisms for making the concepts in Star visible. Other such mechanisms are Star's property and option sheets. Most ob- jects in Star have properties. A prop- erty sheet is a two-dimensional, form- like environment that displays those properties. Figure 3 shows the character property sheet. It appears on the screen whenever you make a text selection and push the PROPER- TIES key. It contains such properties as type font and size; bold, italic, underline, and strikeout face; and superscript /subscript positioning. In- stead of having to remember the properties of characters, the current settings of those properties, and, worst of all, how to change those properties, property sheets simply show everything on the screen. All the options are presented. To change one, you point to it with the mouse and push a button. Properties in ef- fect are displayed in reverse video. This mechanism is used for all properties of all objects in the system. Star contains a couple of hundred properties. To keep you from being overwhelmed with information, property sheets display only the properties relevant to the type of ob- ject currently selected (e.g., character, paragraph, page, graphic line, formula element, frame, docu- ment, or folder). This is an example of "progressive disclosure": hiding complexity until it is needed. It is also one of the clearest examples of how an emphasis on visibility can reduce the amount of remembering and typ- ing required. Property sheets may be thought of as an alternate representation for ob- 262 April 1982 © BYTE Publications Inc I m J 9 \ ^ fi ... . jEarar 'THAT WORKS GREAT!" Planning an on-time, on-budget proj- ect has always been hard work. But our new VisiSchedule™ program can help you and your personal computer make short work of it. The VisiSchedule program is a fast and easy way to control projects, level resources, meet deadlines, and beat cost targets. The VisiSchedule program instantly shows you the critical path among your project's tasks. It allo- cates all costs and personnel, and specifies earliest/latest start dates, slack times, holidays, prerequisites and deadlines for each task. And it produces summaries, time charts, and milestone reports for management. You can actually develop your project as you enter data, investigate tradeoffs between manpower, costs and time. Ask "what if?" . . . add, move, slip or change any task, skill level or cost, and the VisiSchedule ©1982VisiCorp program automatically displays the impact of your changes. This makes it a snap to keep schedules and costs current, too. While the VisiSchedule program does a lot by itself, it can do even more for you when used with other Visi™ programs. That's because they're all inter-related, just like your needs and tasks, to give you a fully integrated solution. For example, automatically transfer the cost data to our VisiTrend/Plot™ program and analyze cause-and-effect relationships. Then instantly plot the results in charts and graphs for better communication. In addition, our series includes the VisiCalc,® VisiFile,™ VisiDex,™ VisiPlot™ VisiTerm™ andDesktop/PLAN™ programs. Ask your retail computer store salesperson for a demonstration of the VisiSchedule program. Discover how easy it is to make short work of plan- ning and budgeting all your work. VlSlSCHEDULEfROM VISICORF PERSONAL SOFTWARE" Circle 56 on inquiry card Microline 84 (Parallel) $1059 88 DELIVERED □ 200 cps bidirectional printing □ 50 cps proportional mode □ Enhanced/emphasized print D Dot-addressable graphics □ Tractor/ friction feed up to 16" □ Program-selectable character size Microline Printers Microline 80 $369 88 Microline 82A $484 88 Microline 83A $749 M Okigraph ROM — adds Hi-Res capabilities to 82A and 83A Printers $89** NEC Printers NEC PC-8023A-C $499 88 Epson Printers MX-80 w/Graftrax $474 88 MX-80/F-T S569 88 MX-80/F-T w/Graftrax S619 88 MX-100 S719 88 Graftrax S89 88 Centronics Printers Centronics 739 (Parallel) $539 88 Centronics 739 (RS-232-C) $644 88 2-Color Adapter S69 88 C.ltoh Printers C.Itoh Comet I $284 88 C.Itoh Pro Writer w/3K buffer (parallel and serial) $639** C.Itoh F-10 Daisy Wheel (40cps) $1564 88 Cables and interfaces available for the Apple, Atari, CBM/PET, and TRS-80 microcomputers Orders & Information: CALL (603)-673-8857 Orders Only: CALL (800)343-0726 We accept COD's-No surcharge for credit cards-No charge for UPS shipping Stock shipments next day-All equip- ment factory fresh w/MFG warranty Prices subject to change HIGH TECHNOLOGY AT AFFORDABLE PRICES I HE BOTTOM 'LINE 12 Johnson Street, Milford NH 03055 search fur- By matching In 3 TEXT AND PROPERTIED IGNORE CASE EN TIRE DOCUMENT REST OF DOCUMENT O J PRE NT SELECTION EHEig Change to By altering E TEXT AND PROPERTIES CONFIRM EACH CHANCE i ' i 1 1 1 n i ii i iii.iii IIIIIIIIIIIIIIIIIMIIII I M I I II M I I I I I I I I M I I I T Figure 4: The option sheet for the Find command showing both the Search and Substitute options. The last two lines of options appear only when CHANGE IT is turned on. jects. The screen shows you the visi- ble characteristics of objects, such as the type font of text characters or the names of icons. Property sheets show you the underlying structure of ob- jects as they make this structure visi- ble and accessible. Invisibility also plagues the com- mands in some systems. Commands often have several arguments and op- tions that you must remember with no assistance from the system. Star addresses this problem with option sheets (see figure 4), a two-dimen- sional, form-like environment that displays the arguments to commands. It serves the same function for com- mand arguments that property sheets do for object properties. What You See Is What You Get ''What you see is what you get" (or WYSIWYG) refers to the situation in which the display screen portrays an accurate rendition of the printed page. In systems having such capabilities as multiple fonts and variable line spacing, WYSIWYG re- quires a bit-mapped display because only that has sufficient graphic power to render those characteristics ac- curately. WYSIWYG is a simplifying tech- nique for document-creation systems. All composition is done on the screen. It eliminates the iterations that plague users of document com- pilers. You can examine the ap- pearance of a page on the screen and make changes until it looks right. The printed page will look the same (see figure 5). Anyone who has used a document compiler or post-processor knows how valuable WYSIWYG is. The first powerful WYSIWYG editor was Bravo, an experimental editor developed for Alto at the Xerox Palo Alto Research Center (see reference 12). The text-editor aspects of Star were derived from Bravo. Trade-offs are involved in WYSIWYG editors, chiefly having to do with the lower resolution of display screens. It is never possible to get an exact representation of a printed page on the screen since most screens have only 50 to 100 dots per inch (72 in Star), while most printers have higher resolution. Completely accurate character positioning is not possible. Nor is it usually possible to represent shape differences for fonts smaller than eight points in size since there are too few dots per character to 264 April 1982 © BYTE Publications Inc TEK 2200 SERIES DUAL TRACE OSCILLOSCOPES THE PERFORMANCE/ PRICE STANDARD 3 ?■ ] L .-..-,. ,-v,. IGMK/ OSCILLQ9COPE M. ;•": r— i f"™* c— I CL (■•) m Tfektronix 2213 Introducing a direct line to a 60 MHz Tektronix scope built for your bench! From the world's most respected name in oscil- loscopes: a new scope, plus a new direct order number, that finally makes it practical to put Tektronix quality on your bench ... at work or home. Among professional en- gineers and technicians there is no substitute for the performance and reliability of Tektronix oscilloscopes. Now, for the first time, Tektronix is offering an ad- vanced scope at an un- precedented low price — and has a direct order line that lets you get your order processed today! The scope: the 2213. Its radical new design brings you Tektronix quality for well below what you would pay for lesser-name scopes. The 2213's practical de- sign includes 65% fewer mechanical parts, fewer circuit boards, electrical connectors and cabling. Result: a lower price for you plus far greater reliability Yet performance is pure Tektronix: there's 60 MHz bandwidth for digital and high-speed analog circuits. The sensitivity for low signal measurements. The sweep speeds for fast logic families. A complete trigger system for digital, analog or video waveforms. And new high- performance Tektronix probes are included! 2213 PERFORMANCE DATA Bandwidth: Two channels, dc— 60MHzfrom10V/div to 20 mV/div (50 MHz from 2mV/divto10mV/div). Sweep speeds: Sweeps from 0.5 s to 50 ns (to 5 ns/div with X10 mag). Sensitivity: Scale factors from 100 V/div(10X probe) to 2 mV/div(1X probe). Ac- curate to ± 3%. Ac or dc coupling. Delayed sweep meas- urements: Standard sweep, intensified after delay, and delayed. (Need dual time-base performance and timing accuracy to ± 1.5%? Ask about our 2215 priced at $1400.) Complete trigger system: Modes include TV field, normal, vertical mode, and automatic; internal, exter- nal, and line sources; vari- able holdoff . Probes: High perform- ance, positive attachment, 10-14 pF and 60 MHz at the probe tip. The price: Just $1100 complete*. Order direct from Tektronix National Marketing Center. Phones are staffed by technical people to answer your questions about the 2213. Your direct order includes a 15-day return policy and full Tektronix warranty. Now it's easier than ever to get your hands on a Tek scope! ORDER TOLL-FREE 800-547-1845 Ask for Department 100 (In Oregon, Alaska and Hawaii: 1-503-627-5402 collect.) Lines are open from 8 am EST to 5 pm PST 'Price FO.B., Beaverton, OR. Tektronix COMMITTED TO EXCELLENCE Copy right ©1982 Tektronix, Inc. All rights reserved. 121 , U ,1, M , * A ,1, ,i, , l , ,1, A ,1, ,1, * * i'i i'i A i'i i»i *\ ■'■ A * i>i *> i'i i^i ■'■ ■*■ i*i ■ ' ■ i'i *r U * A iip ,l i'i I'l J . .'. l'l lil I I i l l 'I I' H I .1; ill ill .■■ i h ill |l. .1. .1. ill .1. ,1 1 , . h ,1, .1. ill ■■! l h |l| ,1, ,1, |l| .*. ,1, ,1. ,1, ■>. ,1, ,1, ,l| .'■ ,1, M ,1, ill ,1, ,1 k 1 1 I| |l I I I I I I I | |l I, ,1 , 1- Q Demo Document I DCEIDlZ5EiD:; XEROX 801 Star Information System User-Interface Design To make it easy to compose text and graphics, to do electronic filing, printing, and mailing all at the same workstation, requires a revolutionary user-interface design, Bit-map display - Each of the 827,392 dots on the screen is mapped to a bit in memory; thus, arbitrarily complex images can be displayed, STAR, displays all fonts and graphics as they will be printed, In addition, familiar office objects such as documents, folders, file drawers and in-baskets are portrayed as r e o o g n i z ab 1 e i m a g e s , The. incuse - A unique pointing device that allows the user to quickly select any text, graphic or office object on the display, See and Point All Star functions are visible to the user on the keyboard or on the screen, The user does filing and retrieval by se lee tine; them with the mouse and touching the MOVE, COPY, DELETE or PROPERTIES command keys, Text and graphics are edited with the same keys, i DISPLAY: familiar office objects qp fnl MOUSE: select ^ ^J objects, menus OYBQAAO: delete HJW^. COf>y o6pCCt3 Productivity under the old and the new 1 00 i— 979 1980 1 981 1982 Shorter Production Times Experience at Xerox with prototype work- stations has shown shorter production times and lower costs, The following equation expresses this, A n: ££%)$%• ICO :' = 1 + n4*- Star users are likely to do more of their own composition and layout, controlling 1 the entire process including printing and distribution, Text and Graphics To replace typesetting, Star offers a choice of type fonts and sizes, from 8 point to 24 point. fie** i$ a lerctan es of 8 ^>:in,t tt-*t , Here is £ L^it^Jice of 10 -point tert, Here is a sentence of 12 -point text. Hern is a s$ n te n c© o f 1 4-p o i n t te :< t. Here is a sentence of 18-point text. nmnnnn i nii i iH i iiiiiiii i i i iin i m wt nifim ri t n n t n t i ih ii iii i iii i r r i i mi i im i f f ii i ii i i i ii i Figure 5: A Star document showing multicolumn text, graphics, and formulas. This is the way the document appears on the screen. It is also the way it will print (at higher resolution, of course). 266 April 1982 © BYTE Publications Inc Circle 140 on inquiry card. Although the Datasouth DS180 matrix printer may not exactly rate as a work of art, our customers have a very high opinion of its value. Over the past year, we have shipped thousands of DS180 printers to customers throughout the world. Many of our sales now come in the form of repeat business— a strong testimonial to the acceptance of The success of the DS180 in a very competitive market did not happen by accident; rather through our sensitivity to the needs of the industry. This sensitivity we carry through research and development, production and quality con- trol and finally to after sales support and service. Recently we introduced new enhancements to make the DS180 printer even more versatile. Dot addressable raster scan graphics produces output of computer generated charts, maps and graphs at a resolution of 75 x 72 dots per inch. Variable horizontal pitch selection allows printing at 10, 12 or 16.5 characters per inch plus double wide printing at 5, 6 or 8.25 characters per inch. The expanded 2K FIFO print buffer handles a full CRT screen dump at up to 9600 baud without de- laying the host system. We also offer transparent mode for isolat- ing communications problems, and for APL users, the dual ASCII/ Check our list of featuresandwethinkyou will agree thattheDS180 offers the most complete performance package in matrix printers. <\NDARD FEATURE! The DS180 is available nationwide through our network of sales/service distributors. ^r ** £_ ■ ■ ■ — 4.^- computer corporation P.O. Box 240947 • Charlotte, NC 28224 • 704/523-8500 be recognizable. Even 10-point ("nor- mal" size) fonts may be uncomfort- ably small on the screen, necessitating a magnified mode for viewing text. WYSIWYG requires very careful design of the screen fonts in order to keep text on the screen readable and attractive. Nevertheless, the increase in productivity made possible by WYSIWYG editors more than outweighs these difficulties. Universal Commands Star has a few commands that can be used throughout the system: MOVE, COPY, DELETE, SHOW PROPERTIES, COPY PROPERTIES, AGAIN, UNDO, and HELP. Each performs the same way regardless of the type of object selected. Thus, we call them "universal" or "generic" commands. For example, you follow the same set of actions to move text in a document and to move a line in an illustration or a document in a folder: select the object, push the MOVE key, and indicate a destination. (HELP and UNDO don't use a selec- tion.) Each generic command has a key devoted to it on the keyboard. These commands are far more basic than the commands in other computer systems. They strip away the extraneous application-specific semantics to get at the underlying principles. Star's generic commands derive from fundamental computer- science concepts because they also underlie operations in programming languages. For example, much pro- gram manipulation of data structures involves moving or copying values from one data structure to another. Since Star's generic commands em- body fundamental underlying con- cepts, they are widely applicable. Each command fills a variety of needs, meaning fewer commands are required. This simplicity is desirable in itself, but it has another subtle ad- vantage: it makes it easy for users to form a model of the system. People can use what they understand. Just as progress in science derives from sim- BYTEWRITER DAISY WHEEL PRINTER LETTER QUALITY PRINTER AND TYPEWRITER IN ONE PACKAGE The BYTEWRITER is a new Olivetti Praxis 30 electronic typewriter with a microprocessor controlled driver added internally. -"*mmmsmam $795 plus shipping Dealer Inquiries Invited FEATURES • Underlining • 10, 12, or 15 characters per inch switch selectable • 2nd keyboard with foreign grammar symbols switch selectable • Changeable type daisy wheel • Centronics-compatible parallel input operates with TRS-80, Apple, Osborne, IBM and others • Cartridge ribbon • Typewriter operation with nothing to disconnect • Service from any Olivetti dealer • Self test program built in. BYTEWRITER 125 NORTH VIEW RD., ITHACA, N.Y. 148SO (607) 272-1 132 Praxis 30 is a trademark of Olivetti Corp TRS-80 is a trademark of Tandy Corp, BYTEWRITER is a trademark of Williams laboratories. pie, clear theories, progress in the usability of computers is coming to depend on simple, clear user inter- faces. MOVE is the most powerful com- mand in the system. It is used during text editing to rearrange letters in a word, words in a sentence, sentences in a paragraph, and paragraphs in a document. It is used during graphics editing to move picture elements, such as lines and rectangles, around in an illustration. It is used during formula editing to move mathemati- cal structures, such as summations and integrals, around in an equation. It replaces the conventional "store file" and "retrieve file" commands; you simply move an icon into or out of a file drawer or folder. It eliminates the "send mail" and "receive mail" commands; you move an icon to an out-basket or from an in-basket. It replaces the "print" command; you move an icon to a printer. And so on. MOVE strips away much of the historical clutter of computer com- mands. It is more fundamental than the myriad of commands it replaces. It is simultaneously more powerful and simpler. Much simplification comes from Star's object-oriented interface. The action of setting properties also re- places a myriad of commands. For ex- ample, changing paragraph margins is a command in many systems. In Star, you do it by selecting a paragraph object and setting its MARGINS property. (For more in- formation on object-oriented lan- guages, see the August 1981 BYTE.) Consistency Consistency asserts that mecha- nisms should be used in the same way wherever they occur. For example, if the left mouse button is used to select a character, the same button should be used to select a graphic line or an icon. Everyone agrees that consisten- cy is an admirable goal. However, it is perhaps the single hardest characteristic of all to achieve in a computer system. In fact, in systems of even moderate complexity, con- sistency may not be well defined. A question that has defied consen- 268 April 1982 © BYTE Publications Inc Circle 70 on inquiry card. Circle 294 on inquiry card. Give your system some NEC, and watch its performance soar. Hie impressive new NEC dot matrix printer. Parallel interface, 100 cps, 2K buffer, pin or feed. Stunning performance and versatility in the hottest new peripheral of the year. Peripherals from NEC can make almost any computer system better. Owners of Apple®, Radio Shack®, Atari®, IBM R , and many other personal computers will find their equipment to be compatible with NEC's famous monitors, as well as our highly-featured new PC-8023A dot matrix printer. (Some configurations may require a different interface.) Ask your dealer for a demonstration. Productivity at your fingertips : ■: : NEC Home Electronics (USA) Pergonal Computer Division 1401 Estes Avenue Elk Grove Villaqe.IL 60007 sus in Star is what should happen to a document after it has been printed. Recall that a user prints a document by selecting its icon, invoking MOVE, and designating a printer icon. The printer absorbs the docu- ment, queuing it for printing. What happens to that document icon after printing is completed? The two plausible alternatives are: 1. The system deletes the icon. 2. The system does not delete the icon, which leads to several further alternatives: 2a. The system puts the icon back where it came from (i.e., where it was before MOVE was invoked). 2b. The system puts the icon at an arbitrary spot on the Desktop. 2c. The system leaves the icon in the printer. You must move it out of the printer explicitly. The consistency argument for the first alternative goes as follows: when you move an icon to an out-basket, the system mails it and then deletes it from your Desktop. When you move an icon to a file drawer, the system files it and then deletes it from your Desktop. Therefore, when you move an icon to a printer, the system should print it and then delete it from your Desktop. Function icons should behave consistently with one another. The consistency argument for the second alternative is: the user's con- ceptual model at the Desktop level is the physical-office metaphor. Icons are supposed to behave similarly to their physical counterparts. It makes sense that icons are deleted after they are mailed because after you put a piece of paper in a physical out- basket and the mailperson picks it up, it is gone. However, the physical analogue for printers is the office copier, and there is no notion of deleting a piece of paper when you make a copy of it. Function icons should behave consistently with their physical counterparts. There is no one right answer here. Both arguments emphasize a dimen- sion of consistency. In this case, the dimensions happen to overlap. We eventually chose alternative 2a for the following reasons: 1. Model dominance — The physi- cal metaphor is the stronger model at the Desktop level. Analogy with physical counterparts does form the basis for people's understanding of what icons are and how they behave. Argument 1 advocates an implicit model that must be learned; argu- ment 2 advocates an explicit model that people already have when they are introduced to the system. Since people do use their existing knowl- edge when confronted with new sit- uations, the design of the system should be based on that knowledge. This is especially important if people are to be able to intuit new uses for the features they have learned. 2. Pragmatics — It is dangerous to delete things when users don't expect it. The first time a person labors over a document, gets it just right, prints it, and finds that it has disappeared, that person is going to become very nervous, not to mention angry. We also decided to put it back where it came from (2a instead of 2b or 2c) for the pragmatic reason that this in- volves slightly less work on the user's part. 3. Seriousness — When you file or mail an icon, it is not deleted entirely from the system. It still exists in the file drawer or in the recipients' in-bas- kets. If you want it back, you can move it back out of the file drawer or send a message to one of the recip- ients asking to have a copy sent back. Deleting after printing, however, is final; if you move a document to a printer and the printer deletes it, that document is gone for good. One way to get consistency into a system is to adhere to paradigms for operations. By applying a successful way of working in one area to other areas, a system acquires a unity that is both apparent and real. Paradigms that Star uses are: • Editing — Much of what you do in Star can be thought of as editing. In addition to the conventional text, graphics, and formula editing, you manage your files by editing filing windows. You arrange your working environment by editing your Desk- top. You alter properties by editing property sheets. Even programming can be thought of as editing data structures (see reference 16). • Information retrieval — A lot of The HOMEBRAIN™ is a ded icated microcomputer system in a stand-alone package. HOME- BRAIN'S™ I/O potential exceeds 300 channels. ACHIEVE TOTAL HOME CONTROL • Energy Management • Home Security • Lighting Control • Safety Monitoring • Appliance Control THE HOMEBRAIN™ IS evaluate THE HOMEBRAIN™ A B i>] E« ■32 Channels Buffered Input -8 Relay Output -Uninterruptable Power Supply -CPU, Communica- tions, 256 Channel AC Wireless Con- trol the First Total Home Control Computer • Communicate with the HOMEBRAIN™ using your personal computer RS232 Inter- face • HOMEBRAIN™ controls your home using your define logic sequences • Logic diagrams, timers, counters, alarm clocks, calendars, are directly implemented by the HOMEBRAIN ™ microprocessor • HOMEBRAIN ™ logs controlled operating times for the month The HOMEBRAIN ™ operates totally inde- pendent of your personal computer. Crashing your computer will not crash HOMEBRAIN « leaving your home defenseless. Order Now By Calling Toil-Free 1-800-228-2028 EXT. 332 ^jCH? Lines Open 8 AM To 6 PM C.S.T. Just give us your Name, Shipping, Address and Visa or MasterCard number and we will charge the $750.00 purchase price, plus $20.00 shipping (N.J. residents add 5% sales tax) to your account. Or, SEND* your CHECK* or MONEY ORDER* to: HYPERTEK, INC 30-4 FARM ROAD SOMERVILLE, NEW JERSEY 08876 'Sending your check will qualify you for an INTRODUCTORY REBATE of 10%. Allow 6-8 weeks for delivery. 270 April 1982 © BYTE Publications Inc Circle 198 on inquiry card. Childhood's End • . - The 68000 ^\ . ••■• ADDRESSING THEnffl FRONTIER... THE MICROCOMPUTER COMES OF AGE. • SAGE COMPUTER TECHNOLOGY IS MOW MANUFACTURING A 68000 BA5ED SINGLE-BOARD MICROCOMPUTER SYSTEM WHiCH'DEUWERS THE HIGHEST. PERFORMANCE PER UNIT PRICE OF Am COMPUTER IH HISTORY. Vi V. • THE SAGE II MICROCOMPUTER HAS THE FOLLOWING FEATURES: . # • INTERRUP^RIVENs^MZ 68000 MICROPROCESSOR • 'z MILLION y INSTRUCTIONS PER SECOND, NO WAIT STATES • WILL ADDRESS 16 MEGABYTE5WITH UP TO 112 MEGABYTE OP PARITY RAM ON BOARD • UP JO ±3 r ME;i, l .*il.il.*;,<.*il,i l i,l,il,,^il,ili,l,,l.il.,i,iliil,ili,l i'i i'i i'i .I. i'. ■ .'. i' ^ »i .'. .'. .'. ■'■ J i. i. ■'. .1. i>, ,', * ■■■ J. .k ,ii .i, .i. j. ■'. rf. ^, ^i ,k .i. ,i. ' ii, ^i ,i, ■■■ ,ii ' .i. i i i ,i r .i ' i ' i " ii, " ^ ,K .I, iii ' i t . .i. '^' .i, .i. ' .ii.i, .1. I Keyboard Interpretation in in i i i w n I'ZI m 131 nz 5Z 1*51 53 I K l>j I ■> I sn :■ I'S'I l<=> (2) X |., ijoj U => iflf TEL ■■■* ,/ 1[ § I tlMllWllWlt^j ■ ^ I II III III lit y*- ..i .^ l V l l llL f D : F hvPPPPPHVP I H •: : : : : ::: : : i v ' . ' . ' .". ' . ' . '?' . l;hift 1/8 I 1/3 2/3 1/4 / ■■ " ■■ ■ JMH . j n i nnim ! I CI 4 N? II Ih ■ J 3 5/4 ! J E H M <-.V V:> ■ " ■ " ¥ " Vw#w .. . . i u : /o ,' '.' '.' ' ,' V V V V '.' '.' '.' '.' V V '.' V V ', ' V V ',' ',' ',' '.' V '.' '.' '■' '.' V '■' ',' V '.' ' ' V '■' '.' '.' V V V '.' V V ',' V '.' ',' V V ',' '.' '.'"',' '.' '.' V V '.' •yyyyyyy^^ Figure 6: The keyboard-interpretation window serves as the source of characters that may be entered from the keyboard. The character set shown here contains a variety of office symbols. power can be gained by applying in- formation-retrieval techniques to in- formation wherever it exists in a sys- tem. Star broadens the definition of "database." In addition to the tradi- tional notion as represented by its record files, Star views file drawers as databases of documents, in-baskets as databases of mail, etc. This teaches users to think of information retrieval as a general tool applicable through- out the system. • Copying — Star elevates the concept of "copying" to a high level: that of a paradigm for creating. In all the vari- ous domains of Star, you create by copying. Creating something out of nothing is a difficult task. Everyone has observed that it is easier to modify an existing document or pro- gram than to write it originally. Picasso once said, "The most awful thing for a painter is the white can- vas . . , To copy others is nec- essary." (See reference 20.) Star makes a serious attempt to alleviate the problem of the "white canvas" by making copying a practical aid to creation. For example, you create new icons by copying existing ones. Graphics are created by copying existing graphic images and modify- ing them. In a sense, you can even type characters in Star's 2 16 -character set by "copying" them from keyboard windows (see figure 6). These paradigms change the very way you think. They lead to new habits and models of behavior that are more powerful and productive. They can lead to a human-machine synergism. Star obtains additional consistency by using the class and subclass no- VORK lO BASF-DPS WORLD STANDARD TAPE DATA m*"*- TRAC C-10 C-20 • BLANK COMPUTER CASSETTES • UNIVERSAL INDUSTRY ACCEPTANCE • MONEY BACK GUARANTEE LENGTH 1 DOZEN 2 DOZEN" _ ^^^\ C-10 " 8.00_^__14.40 /JKlS/ W*^ C-20 1000 18.00_^Kj' Shipping: 1 doz. $2. 2 doz. $3.50 addt'l. doz., $1. Calif, residents, add 6% sales tax For IMMEDIATE SHIPMENT on Credit Card Orders, Call: 213/710-1430 VORK lO Computer ware 24573 Kittridge St., #8-2, Canoga Park. CA 91307 Circle 444 on inquiry card. 272 April 1982 © BYTE Publications In ONE BOARD CP/M SYSTEM! M**lk©5, includ- ing the DBLDOS diskette. yi^iW.W Circuit misapplication causes diskette read, format problems . High resolution key to reliable data separation GARLAND, TEXAS — The Percom SEPARATORS does very well for the Radio Shack TRS-80* Model I computer what the Tandy disk controller does poorly at best: reli- ably separates clock and data signals during disk-read operations. Unreliable data-clock separation causes for- mat verification failures and repeated read retries. CRC ERROR-TRACK LOCKED OUT The problem is most severe on high-number (high-density) inner file tracks. As reported earlier, the clock-data separa- tion problem was traced by Percom to misap- plication of the internal separator of the 1771 drive controller IC used in the Model L The Percom Separator substitutes a high- resolution digital data separator circuit, one which operates at 16 megahertz, for the low- resolution one -megahertz circuit of the Tandy design. Separator circuits that operate at lower frequencies — for example, two- or four- megahertz — were found by Percom to provide only marginally improved performance over the original Tandy circuit. The Percom solution is a simple adapter that plugs into the drive controller of the Expansion Interface (EI). Not a kit — some vendors supply an un- tested separator kit of resistors, ICs and other paraphernalia that may be installed by mod- ifying the computer — the Percom SEPARATOR is a fully assembled, folly tested plug-in module. Installation involves merely plugging the SEPARATOR into the Model I EI disk con- troller chip socket, and plugging the controller chip into a socket on the SEPARATOR. The SEPARATOR, which sells for only $29. 95 , may be purchased from authorized Per- com retailers or ordered directly from the fac- tory. The factory toll-free order number is 1-800-527-1222, Ed. note: Opening the TRS-80 Expansion In- terface may void the Tandy limited 90-day warranty. Circle 326 on inquiry card. The Percom DOUBLER II is available from authorized Percom retailers, or may be ordered direct from the factory. The factory toll-free order number is 1-800-527-1222. Ed. note: Opening the TRS-80 Expansion In- terface may void the Tandy limited 90-day warranty. Circle 327 on inquiry card. All that glitters is not gold OS-80® Bridging the TRS-80* software compatibility gap Compatibility between TRS-80* Model I diskettes and the new Model III is about as genuine as a gold- plated lead Krugerrand. True, Model I TRSDOS* diskettes can be read on a Model III. But first they must be converted and re- recorded for Mode! Ill operation. And you cannot write to a Model I TRSDOS* dis- kette. Not with a Model III. You cannot add a file. Delete a file. Or in any way modify a Model I TRSDOS diskette with a Model III computer. Furthermore, your converted TRSDOS diskettes cannot be converted back for Model I operation. TRSDOS is a one-way street. And there's no re- treating. A point to consider before switching the company's payroll to your new Model III. Real software compatibility should allow the di- rect, immediate interchange ability of Model I and Model III diskettes. No read-only limitations, no conversion/re-recording steps and no chance to be left high and dry with Model III diskettes that can't be run on a Model I. What's the answer? The answer is Percom 1 s OS- 80® family of TRS-80 disk operating systems. OS-80 programs allow direct, immediate inter- changeability of Model I and Model III diskettes. You can run Model I single-density diskettes on a Model III; install Percom's plug-in DOUBLER 1 ' adapter in your Model I, and you can run double- density Model III diskettes on a Model I. There's no conversion, no re-recording. Slip an OS-80 diskette out of your Model I and in- sert it directly in a Model III. And vice-versa. Just have the correct OS-80 disk operating sys- tem — OS-80, OS-80D or OS-80/III — in each com- puter. Moreover, with OS-80 systems, you can add, de- lete, and update files. You can read and write disket- tes regardless of the system of origin. OS-80 is the original Percom TRS-80 DOS for BASIC programmers. Even OS-80 utilities are written in BASIC. OS-80 is the Percom system about which a user wrote, in Creative Computing magazine, "... the best $30.00 you will ever spend."! Requiring only seven Kbytes of memory, OS-80 disk operating systems reside completely in RAM. There's no need to dedicate a drive exclusively for a system diskette. And, unlike TRSDOS, you can work at the track sector level, defining and controlling data formats — in BASIC — to create simple or complex data struc- tures that execute more quickly than TRSDOS files. The Percom OS-80 DOS supports single-density operation of the Model I computer — price is $29.95; the OS-80D supports double-density opera- tion of Model I computers equipped with a DOUB- LER or DOUBLER II; and, OS-80/III — for the Model III of course — supports both single- and double-density operation. OS-80D and OS-80/III each sell for $49.95. Circle 328 on inquiry card. PRICES AND SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE. PRICES DO NOT INCLUDE HANDLING AN D SHIPPING. PERCOM DATA COMPANY, INC. 11220 Pagemill Road Dallas, Texas 75243 (214) 340-7081 ^Trademark of Percom Data Company, Inc. 'TRS-80 and TRSDOS are trademarks of Tandy Corporation which has no relationship to Percom Data Company. tCreative Computing Magazine, June, 1980, page 26. Circle 6 on inquiry card. The Birth of UNIX™ for CP/M™! fflicrcSMI The . . . • POWER of UNIX ►POPULARITY OF CP/M Available for adoption by: CP/M SOFTWARE DEVELOPERS CP/M SOFTWARE USERS CP/M Compatibility Console Input/Output Redirection Automatic Command Fife Search Path Multiple Commands Per Line » Loads and Executes as a norma! program' un< "installing itself undef the CP/M operating sys • Other CP/M programs - editors/word process assemblers— may then be run using ail Mtcrc • CP/M compatibility is generally not affected t • Adds UNIX Power without losing CR/M'Comp • Send Console Output to a Pile instead of or in addition to the screen Example: stat *.* > status ;■- sends "slat" output to file "status" • Take Console Input from a File instead of the Keyboard v Example: ed filename < script - takes "ed" commands from the file "script" • Indispensable for: graphic debugging, saving exact Screen Output f .ltion, etc. • MicroShell finds your program, User concentrates on the big tasks. MicroShell does the details Permits development or data files on one drive and all programs on another • User-specified file types for Automatic Search. Example: ".com", "jnt", etc. • User-specif ied Search Path. Example: Current Drive 1 St, then Drive A, etc. • User types a logical group of commands to be executed Example: compile file; Sink file; file • MicroShell executes the commands one at a time Direct Command File Execution • Files of CP/M or MicroShell commands are executed by MicroShell • User-specified Command Filetypes. Example: ".sh", ".sub", etc. • Argument substitution ($1, $2, etc.) as with CP/M SU8MIT/XSUB iimply by typing file name Additional Features • User definable prompt with Disk Drive and/or User Number optional • install program to customize MicroShell to user's heeds & system • Others - ORDER MANUAL FOR FULL DETAILS $150.00 $ 25.00 • ADOPTION FEE: Manual Only: (VA residents add 4% sales tax) v c VCTCi VISA, MC, Check or Money Order N SY STEMS, IflC. / NEW • 8000 • Mck rther personal, micro,/ mini computers and terminals •The Compucart is the first economically c signed mobile computer workstation. The keyboard shelf adjusts to meet the requirements r. When not in use r running unattended the keyboard is returned to the closed position, the roll-down tambor door is closed and the whole workstation, hardware and software , is secured with one lock. The Compucart is available now at the listed dealers or ask your dealer to contact us as dealer inquiries are invited. COMPUCART DEALERS: INTERNATIONAL Zofarry Enterprises Pty, Australia • Dabus AB, 161 11 Bromma, Sweden NORTH Wolfson Electronics Inc., Southfieid, Ml • Micro Legal. Inc., Minneapolis, MN NORTHEAST Calculator & Computer Center, New Rocnelle, NY • Cyborg, Boston, MA • Microsource Financial, Inc., Watertown. MA • Robert E. Ramsdell, Rockport, MA • Super Business Machines, New York, NY SOUTH AMF Microcomputer, Inc.. Tampa, FL •Central Florida Office Designing a Text Editor? The User Comes First A system's power is measured in ease of use. Steven Jong 38 Riverhurst Road Billerica, MA 01821 In choosing or designing any com- puter system — hardware or soft- ware — the most important considera- tion is the human interface: if a system doesn't work for the user, it's not a working system. This article presents observations on the crucial relationship between human factors and the design of text editors for video-display terminals. These obser- vations are drawn from my ex- perience with a number of editors on computers of various sizes and from software-design and human-factors literature. All the features described here exist on at least one editor. My aim is to give you some things to look for if you want to buy — or write — an outstanding text editor. The first and most important design goal is ease of use. This should surprise no one. James Martin (see reference 7) pointed out back in 1973: 'To be effective [in the next decade], systems will have to be designed from the outside in. The terminal or con- sole operator, instead of being a peripheral consideration, will become the tail that wags the whole dog." Text editors are, to most users, the outermost layer of their computer system — the layer they deal with most. Timesharing users spend over half their time using a text editor, and About the Author Steven Jong, a principal software tech- nical writer, holds a master's degree in science communication from Boston University. editing commands account for about fifteen percent of all commands they enter. Personal-computer users may exceed those figures. Ease of use, therefore, weighs most heavily on editor design. What, then, makes a good text editor? Human-factors literature sug- gests many characteristics of the laudable text editor. Different authors espouse perfectly reasonable but totally contradictory principles. You'll have to evaluate your needs when designing one feature in and another out (see text box on page 298.) Screen Display Features Let's consider what you want or need to see on the text display. The top or bottom display line (but not both) should provide program and system status information, such as the file name, the current file line number, the last command invoked, the time, and program prompts. This keeps you informed as to the system state and is well worth the overhead. Another line could display the cur- rent tab stops and margins, if they are to be controlled by the user (see figure 1). When you enter a keystroke in the middle of a line of text, one of two things may happen. The character at the cursor position may be overstruck by the new character; or the new character may be inserted at the cur- sor position and characters from the cursor position on move to the right to accommodate it. Existing editors use both modes, but overstrike editors require a separate insert /stop- insert function and don't prevent you from accidentally replacing text. From the user's viewpoint, a display mode that allows accidental erasure of text is undesirable. A screen-editor window is limited by the size of the screen. To minimize the effects of this limitation and allow you to browse through text, there must be a command to scroll text, both vertically and horizontally (see figure 2). (An editor that allows horizontal scrolling can display overlong lines as truncated, with the ends of the lines offscreen, which seems most natural.) You should be able to scroll through the file con- tinuously and stop whenever you want. This suggests that scrolling should continue as long as some par- ticular key is depressed and stop the instant the key is released. How fast should the display scroll? The Honeywell WP 6 word processor lets you scroll at the rate of about ten lines per second. This allows brows- ing, but is slow if you want to traverse several screens' worth of text. It also limits scrolling to the text within the current page of memory. The scrolling function built into Radio Shack Model II computers gets you from one end of a file to the other very nicely, but too quickly to read anything. It would be nice to scroll and also maneuver using some other mechanism, such as 'go to string," "go to page," etc. You may want to mark blocks of text for movement, reproduction, or 284 April 1982 © BYTE Publications Inc COMMODORE ST J* :.! i THE WONDER COMPUTER OFTHE1980s.UNDER$300r VIC-20® VS. OTHER HO MECC >MPU1 HERS Product Features Commodore VIC-20 Atari* 400™ TI» 99/4A TRS-80* Color Computer Price* $299.95 $458.95 $499.00 $399.00 Maximum RAM Memory 32K 16K 16K 32K Keyboard Style Full -Size Typewriter Style Flat Plastic Membrane Half-Size Typewriter Style Calculator Style Number of Keys 66 57 40 53 Programmable Function Keys 4 Graphic Symbols On Keyboard 62 Displayable Characters 512 256 64 256 Microprocessor 6502 6502 TI990 6809 Accessible Machine Language YES YES NO YES Upper/ Lower Case Characters YES YES NO NO Operates with all Peripherals (Disk, Printer and Modem) YES NO YES YES Full Screen Editor YES YES NO NO Microsoft Basic Standard N/A N/A $ 99.00 Telephone Modem $109.95 $399.95 $450.00 $154.95 m m mmmmmm 92SBBBKM IX*] y^fl IB r; ' i Mr '>^;r~ ■ i'LK ludes BASIC cartridge required/or programming Read the chart and see why COMPUTE! Magazine V calls the VIC-20 computer "an astounding machine for the price . " Why BYTE 2 raves: " . , , the VIC-20 computer unit is unexcelled as a low-cost consumer computer." Why Popular Mechanics 3 says ". . .for the price of around $300, it's the only game in town that is more than just a game." And why ON COMPUTING INC. 4 exclaims: "What is inside is an electronic marvel ... if it sounds as if I 'm in love with ray new possession, I am." The wonder computer of the 1980s . The VIC-20 from Commodore , world 's leading manufacturer of a full range of desktop computers. See the VIC-20 at your local Commodore dealer and selected stores. J April '81 Issue 2 May '81 issu COMPUTER Circle 92 on inquiry card. S. ..!... .1, Dear. Mom, * ► My. first .day. at .the . computer . camp .has .been. just . swell, . .You, wouldn ' t . believe . what . these . computers . can . do ! . . And . all . the . kids . get . their .own. systems . for .their .very .own! . .I'm. so. happy .you . and . Daddy . decided . to . send . me . here • ^ ► The .bunks .are . kind. of . lumpy, .but .1 .guess . I * 11. get .used. to. them.. .There * s .also. lakes, .and. woods, .and .we .can. play . volleyball . and . baseball . in . the . afternoons . . . The . food . is . pretty . good , . and , we . had . ice . cream . today ! ^ ► I'm. going . to . spend . a . few . days . in . the . LISP . class , . so . I . can . find .out .how. to. do. artificial. intelligence. . .Then. I .can't . decide .whether .to .take .data-base .managemet .or .word. processing. . El* think. maybe. I * 11 .take .word. processing. . .That .way. I .can. write, home . to .you . every . day I ^ ► My. friend .Bobby. wants .me . to . go .play . Space . Invaders. now. . .1 . bet . I .beat .him! ^ LETTER Love , ^ Harold PAGE 1 LINE 16 Press DEL to delete, or RETURN to cancel, Figure 1: An idealized screen-editor display. The larger the display area, the better. Spaces, tabs, and carriage returns are indicated by special symbols. "S" in the tab line indicates single spacing; "**" indicates that the line length is 64 characters; 7" indicates a tab stop. Besides showing its user a window of text, the screen highlights selected blocks, prompts for action, and displays program and system status. deletion. Text editors on some minicomputers display plain text in low-intensity characters and mark blocks using high-intensity characters. Microcomputer-based word processors tend to use inverse- video characters for the same func- tion. A useful, advanced feature is multifile editing. The best way to display multiple files on the screen is to use multiple windows. The screen can, for instance, be bisected by a line of dashes, with one file displayed above and the other below. Some editors dedicate a portion of the screen as a message window for prompts and error messages. This window should not be too large, of course; three or four lines is typical. Many text editors employ the beep signal, a simple and powerful atten- tion-getting device that, unfortunate- ly, is often misused. More than one word-processing system uses the signal in an inconsistent and annoying way: beeping when users enter some things right (sign-in lines, for instance), and yet also beeping when users enter some things incorrectly (a function key during a search); often they re- main silent during many other kinds of errors. In my opinion, the beeper is best left to signaling errors. The coming flood of color com- puters will soon bring a generation of full-color software. Four colors— red, green, blue, and yellow— are prob- ably sufficient for text displays; green is generally acknowledged as easiest on the eyes. Color could highlight a search string, an error message, or a prompt. Color could also mark por- tions of a file. For instance, various parts of a document could be marked in green (draft), yellow (comments), red (technical questions), and so forth. However, color should not be the only distinguishing feature of im- portant messages, because four per- cent of the population are color blind. Word-Processing Features Certain functions apply strictly to word processing, One is a dot-filled display in which each space character is represented by a dot smaller than a period. The dots simplify counting spaces and aligning text vertically. One might argue that a dot-filled screen appears too ''busy," but most users of Wang and Lanier word pro- cessors, which feature dot-filled screens, are happy with them. A good word-processing editor should perform "word wrapping", 286 April 1982 © BYTE Publications Inc fmSt mfixw^w* ' M»"«4Hi§»««M*ii J mm ifm r'r'"' 1 '. ------ *»| CTt,. ...... * ,J » 0OF3T ^i BhhS ^'w , ......J , w^ ^1§| ........ irtmni : ■ w '^r'' m w 1 if,; IV) i Turn your Apple into the world's most versatile personal computer. The SoftCard™ Solution. SoftCard turns your Apple into two computers. A Z-80 and a 6502. By adding a Z-80 microprocessor and CP/M to your Apple, SoftCard turns your Apple into a CP/M based machine. That means you can access the single largest body of microcomputer software in exist- ence. Two computers in one. And, the advantages of both. Plug and go. The SoftCard system starts with a Z-80 based circuit card. Just plug it into any slot (except 0) of your Apple. No modifications required. SoftCard supports most of your Apple peripherals, and, in 6502-mode, your Apple is still your Apple. CP/M for your Apple. You get CP/M on disk with the SoftCard package. It's a powerful and simple-to-use operating system. It supports more software than any other microcomputer operat- ing system. And that's the key to the versatility of the SoftCard/Apple. Circle 275 on inquiry card. BASIC included. A powerful tool, BASIC-80 is included in the SoftCard package. Running under CP/M, ANSI Standard BASIC-80 is the most powerful microcomputer BASIC available. It includes extensive disk I/O statements, error trapping, integer variables, 16-digit precision, exten- sive EDIT commands and string func- tions, high and low-res Apple graphics, PRINT USING, CHAIN and COM- MON, plus many additional com- mands. And, it's a BASIC you can compile with Microsoft's BASIC Compiler. More languages. With SoftCard and CP/M, you can add Microsoft's ANSI Standard COBOL, and FORTRAN, or Basic Compiler and Assembly Lan- guage Development System. All, more powerful tools for your Apple. Seeing is believing. See the SoftCard in operation at your Microsoft or Apple dealer. We think you'll agree that the SoftCard turns your Apple into the world's most versatile personal computer. Complete information? It's at your dealer's now. Or, we'll send it to you and include a dealer list. Write us. Call us. Or, circle the reader service card number below. SoftCard is a trademark of Microsoft. Apple II and Apple II Plus are registered trademarks of Apple Computer. Z-80 is a registered trademark of Zilog, Inc. CP/M is a registered trademark of Digital Research, Inc. CONSUMERS PRODUCTS Microsoft Consumer Products, 10700 Northup Way, Bellevue, WA 98004 . (206) 828-8080 Figure 2: Vertical and horizontal scrolling provide a flexible "window" to text. Con- ceptually, either the screen or the text can be thought of as moving. i.e., a word being typed in that ex- ceeds the specified line length is car- ried down to start a new line. This relieves you of having to decide when to end a line. Word wrapping is one of the two most useful features of a word-processing editor (the other is character deletion). It is possible both to break lines and justify them at the same time; Micropro International's Wordstar microcomputer-based editor does this. When characters are inserted into the middle of a line, a word- processing editor should reformat the rest of the text automatically. In prac- tice, this proves difficult. Some editors, for instance, temporarily clear the screen from the cursor posi- tion to the end of the screen during text insertion (see figure 3). New text can be entered and formatted; when the user signals that insertion is finished, the rest of the text is refor- matted. The ideal editor would refor- mat text continuously during inser- tion, but I have seen no editor that does. Instead, most include a separate "reformat" command to reformat the current paragraph after insertion is finished. Navigating Through the File Now that we know how to display text, we must deal with the problem of finding our way through it. Ad- dressing text is a prerequisite to manipulating text. The more power and flexiblity you have in addressing, the better. The basic cursor movement is "quadridirectional," or up/down/ left /right, universally offered by screen editors. Boundary conditions, however, may vary from one editor to the next. For instance, if the cursor is in column 1 (the left extreme of the screen) and you try to move the cur- sor to the left, one screen editor might treat your action as an error; another editor might oblige the request by moving the cursor to the last character of the previous line. What happens when you try to move the cursor past the end of a line? Usually, editors will not allow cursor movement, or at least text in- sertion, past the end of a line. In prac- tice this proves a limitation, and there is no ease-of-use justification for it. It could, in fact, imply an attempt to enter spaces (perhaps the user is try- ing to make columnar text column by column). Commands that move the cursor a single character at a time are not enough. There should also be com- mands to move by word, line, sentence, paragraph, screen, page im- age, and column; the ability to go to the top or the bottom of a file at a single keystroke is also useful. Com- bining cursor-movement commands with a Repeat key is also very impor- tant (an advanced video terminal may include an automatic-repeat function if a key is held down). An alternative for terminals without repeat functions is to allow com- mands to accept numeric arguments so that a user could, for instance, skip four sentences. Signaling Commands Now 7 we turn to the mechanism by which you signal that you are enter- ing a command (the nature of which is not yet important). Single-char- acter command names are best for fast typing. Screen editors must use nonalphanumeric characters, because alphanumeric keystrokes must always appear as entered. The next simplest arrangement is to use control characters, because the CTL (Con- trol) key is standard on most com- puter keyboards. CTL-W, then, might mean "write file." Of course, entering some command sequences would require two hands. Designers of some computer sys- tems, thinking of novice users, in- 288 April 1982 © BYTE Publications Inc AH-HA! EUREKA! ALL-RIIIGHT! $f Introducing 1 i Popular Computing, 3 the key to understanding, Now you don't have to be a computer professional to unlock all the mysteries, potential, and pleasures of home and small business computers. Popular Com- puting, the new monthly magazine from McGraw- Hill, is the key. Created in response to growing demand for our informative quarterly onComputing, Popular Com- puting explores every aspect of personal com- puters and their use. All reported in easy-to- understand nontechnical language. POPULAR. POPULA, COMPUTING Choosing YourPopi Com i W fiat to Whete [i Buy ft Compun Your SmaU Business Asimov Reviews Asimov Honje Computer Games The answer to i € Computer phobia* ■ ' Even the most computer- unsophisticated reader will find Popular Computing interesting and stimulating. Every issue will contain straight- talking product reviews, special news briefs, and feature articles by famous guest contributors (like Isaac Asimov). There'll even be a helpful glossary of computer jargon we couldn't avoid using, and much, much more. Special Introductory Offer. Send in this coupon to- day, and take advantage of ^f^ 1 Popular Computings Special i 1 ' 1 Introductory Offer. ^gr ^fv m *v < 6 4 T -F crJt O pV^VV> .<> cf& J* y> * COMPUTING THE KEY TO UNDERSTANDING P.O. Box 397, Hancock, NH 03449 "§*" &*" u?*&^f*x* INTERESTED? mmmm^ LETS TALK CONCEPT: PRIVATE COMPUTERS Our marketplace is maturing. Those of you that were around in 1977 will remember what it took then to make a sale... (anything that worked!) The two beautiful faces at the left are evidence that changes have occured in the industry!!! Besides an excellent, well proven S-100, CP/M, Z-80 4MHZ computer system, we have a few extra things to offer. (Not the model!) Delta specializes in something called a Private Computer . It's for those of you systems integrationists that have matured with the market. You stopped assembling systems in your garage a long time ago, but still need a totally flexible computer line that your customers won't find at Wards or Sears. l. A Private Computer means you will never see one of our computer systems on the shelf of your local department store or computer shop. We only sell to systems integrationists who add value to our product. — ^ A Complete Range of Products is available. No other micro company in *J y the world offers a more complete line of equipment to satisfy your needs. f^F • yj e have everything from low end single user systems to the top of the line 64 user distributed processing networks. ^^ The DP Software Library is growing every month. We supply ^■m Accounting, Business Management, Code Writing, Medical, Dental, ^^ * Chiropractic, Word Processing, Property Management and other programs. We have the source code in most cases and can negotiate customization if needed. Video taped training cassetts to aid you and your customers in learning how to use the programs and run the hardware are available. — Factory Support and Service is available in most large cities. There are 66 /W fully stocked factory maintainance centers in the U.S. and 12 outside the -^- * U.S. In more remote areas, our 24 hour fast turnaround component pool can be used to insure reasonable response times to satisfy customers. We have a customer service Hotline independant of sales or service. We have a 24 Hour Modem Engineering Advisory Billboard. ., Our Engineering Assistance and Software Development Program ^L can make headaches turn into profits. We maintain a staff of Engineers and ^^ * Programmers whose services can be leased to expand your range of services. Problems from something as simple as hooking up a new printer or modifying an existing software program to customize a screen display can be resolved with this service. ^^ Financial Assistance is available through a flexible credit program that f m can not only get the product to you quickly but keep your cash busy where it ^^ • will do the most good. 30 - 60 - 90 day flooring plans can be arranged to allow you to collect your money before you have to pay us. Sherry Starkey is on line right now at Delta to direct you to your area representative. If you have a half inch Beta or VHS video machine, ask Sherry for a sales demonstration in your own home or office. See the Plant, the People and the Program. DELTA PRODUCTS INC. • 15392 ASSEMBLY LANE, HUNTINGTON BEACH, CA 92649 (714)898-1492 • MON to FRI - 8 AM to 5 PM • TELEX: 681-367 DELTMAR HTBH Circle 145 on inquiry card. S ...!.... 1 . 2 . and. slowed . to .a .halt. - ► Most . of . the . flanges .were. undamaged . by . the . accident , However, .the . flanges . closest .to .the . input .valve .were . slightly . scratched, . and . those , actually . struck .by. the. chain .were . contaminated .with .oil. . .This .was .judged .not , serious. .■ TRIPREPORT PAGE 12 LINE 44 We . therefore .recommend , the . following Figure 3: Text insertion on a typical minicomputer-based word processing editor. The screen is cleared from the point of insertion; new text is displayed in proper format. The display logic is simpler than for reformatting the screen after every character is entered. In the illustration, inserted text is highlighted. variably turn to special-function keys for signal commands. They feel the simplest possible arrangement is to give each function its own labeled key, reinforcing the what-you-see-is- what-you-get nature of screen editors. But before assigning all func- tions to dedicated keys, a designer should consider what adjustments skilled typists must make to reach function keys located on the periphery of a keyboard, and whether certain functions are too im- portant to be invoked with single keystrokes. The rush toward function keys in the business market may slow as human-factors specialists research these questions. In the microcom- puter marketplace, function keys are uncommon, and a general-purpose screen editor would be fatally limited if it required function keys. Ease-of-use considerations suggest the use of prompts for procedural commands. If you press the Search key on a Wang word processor, the system prompts: "For what?" in the message window. It searches for whatever is typed in response to the prompt. Press the Delete key; it prompts: "Delete what?" Mark text for deletion, and press the Execute key to actually delete it. This prompt- ing helps beginning users, though in time they become conditioned to ig- nore the prompts. Commands can be assigned to in- dividual keys mnemonically, phys- ically, or symbolically. For example, to signal quadridirectional cursor movement, a mnemonic assignment scheme could be U, D, L, and R (for up, down, left, and right); a physical assignment scheme could be W, Z, A, and S (spatially simulating a cursor keypad — try it on your own key- board!); and a symbolic assignment scheme could be *, V, <, and > (symbolizing arrows). There are other possibilities: another mnemonic could be F, B, P, and N (forward, backward, previous, and next); and another physical scheme could be I, J, K, and M (for the right hand instead of the left). All of these arrangements are used on various systems. What- ever the scheme, commands must be logically arranged, even at the ex- pense of leaving out a function because there is no reasonable key to which it can be assigned. A command that is hard to call will be hard to remember and, ultimately, hard to use. If key assignments are not com- pletely logical, the results may be 292 April 1982 © BYTE Publications Inc Can any camera make you a better photographer? We think the answer is "yes" While talent, admittedly, comes first, equipment comes second. And there's a world of difference between cameras. The moment you hold a Hasselblad in your hand you'll sense that difference. When you look into the view ing hood you'll see a big, bright 2V4" x 2V4" image projected onto the ground glass screen. You'll find this experience con- siderably more satis- fying and stimulating than peering with one eye through the tiny eyepiece of a 35mm. The Hasselblad viewing system brings you closest to what your finished photograph will actually look like, which will help improve your results. Formats approx. half actual size Hasselblad's interchangeability is another great creative stimulant. It helps you shape the camera configuration to suit your own ideas, so the camera and your mind's eye can work together as one. For a start, you can interchange the film magazine with other magazines, permitting changes in film types, film capacity and even formats. And you can switch magazines even in mid-roll, with- out wasting a single shot and that includes a Polaroid back. You can also interchange the lens with other Carl Zeiss lenses, for a wide range of optical options. These lenses greatly extend the vision of the camera and open up an exciting range of creative possibilities. You can further adapt your Hasselblad to your own creative needs through a wide number of accessories, including specialized viewfinders, bellows extensions, grips — even an underwater housing. Considering the extra- ordinary scope and versatility of the Hasselblad, the uninitiated might be inclined to conclude that this is a complicated camera. But nothing could be further from the truth. The Hasselblad is designed to be easy to operate enabling the photographer to concentrate on the subject and not on the camera. So if you're looking to improve your photography, look into a Hasselblad. See your Hasselblad dealer or write for our comprehensive brochures, to: Victor Hasselblad Inc., 10 Madison Road, Fairfield, N J. 07006 HASSflBLAD When you shoot for perfection Circle 425 on inquiry card. BYTE April 1982 293 Circle 255 on inquiry card. INDUCTIVE COUPLED MODEM Eliminates noise, vibra- tion problems. Originate/ Answer. Bell 103. Cas- sette port saves data. Money back if hot delighted MFJ-1230 INDUCTIVE COUPLED MO- DEM eliminates room noise, vibration caused by acoustic coupling. Gives more reliable data transfer. Used like acoustic modem. 0-300 Baud, Bell 103 compatible. Originate/ Answer. Half/ Full duplex. RS- 232, TTL, CMOS compatible. Use any com- puter. Cassette tape ports save data. 110VAC or 9V batteries. Crystal controlled. Carrier detect, power LEDs. 9x1 1 /2x4". MFJ-1231, $39.95. Optional cable, soft- ware for Apple II, II Plus. Plugs into game port. No serial board needed. 95 MFJ-1108, AC POWER CENTER. Adds conven- ience, prevents data loss, head bounce, equipment damage. Relay latches power off during power transients. Multi filters isolate equipment, elimin- ate interaction, noise, hash. Var- istors suppress spikes. 3 isolated switched socket pairs. 1 un- switched for clock, etc. Lighted power, reset switch. Pop-out fuse. 3 wire 6 ft. cord. 15A/ 125VAC, 1875 watts. Aluminum case. Black. 18x23/4x2". MFJ- 1107, $79.95. Like 1108 less relay. 8 sockets, 2 unswitched. Other models available. $ 79 95 MFJ-1240 RS-232 TRANSFER SWITCH. Switches computer between 2 peripherals (printer, terminal, modem, etc.). Like having extra port. Pushbutton switches 10 lines (pins 2,3,4,5,6,8,11,15,17,20). Chan- ge plug or cable to substitute other lines. Pushbutton reverses transmit - receive lines. LEDs monitor pins 2,3,4,5,6,8,20. PC board eliminates wiring, crosstalk, line interference. 3 RS-232 25 pin connectors. 7 x2x6 inches. Order from MFJ and try it. If not delighted, return within 30 days for refund (less shipping). One year unconditional guarantee. Order yours today. Call toll free 800-647-1800. Charge VISA, MC. Or mail check, money order. Add $4.00 each for shipping and handling. CALL TOLL FREE . . . 800-647-1800 Call 601-323-5869 for technical information, or- der/repair status. Also call 601-323-5869 out- side continental USA and in Mississippi ENTERPRISES, INCORPORATED 921 Louisville Road, Starkville, MS 39759 MFJ catastrophic. I recall a Boston Univer- sity student who some years ago ran afoul of the RAX line editor written for the school's IBM 360/50 system. He went to a computing center ad- viser and explained that he was searching for what he thought was the next line of his file. Although he had checked most of his file, he couldn't find the elusive line. When the adviser examined the file, she dis- covered that most of it had been deleted. When asked what commands he had been using, the student replied that he didn't know much about the editor, but that U meant go up, and didn't D mean go down? It was a perfectly reasonable assumption; un- fortunately, while U did mean up, N (next) meant down, and D meant delete. The first commands to assign should be the basic ones given in table 1. They form a simple, symmetrical, and complete set of editing functions. Note that the Search command re- quires some sort of command se- quence to signal the editor that the search string has been specified. The Return key is natural for this purpose (at the cost of making the Return character a difficult string to search for). Unless the editor handles routine file I/O (input/output) operations — creating, deleting, reading from, and writing to files — expect it to work only with an operating system. These operations must be invisible to the user. Idiot-Proofing Designers, preoccupied with estab- lishing responses to correct key- strokes, often neglect incorrect ones. Because editors are used so extensive- ly they should never abort, no matter what you enter. The process of "idiot- proofing" interactive programs was described by Anthony Wasserman in 1973 (see reference 11). It involves an- ticipating incorrect entries, missing input, inadvertent keystrokes (e.g., BREAK, CTL, and ESCape), and transmission errors (which are rare in personal computer terminals). An ex- ample of non-idiot-proof hardware is found in some versions of the Apple 294 April 1982 © BYTE Publications Inc II computer keyboard. The Reset key is in a hard-to-miss location— just above the Return key; many applica- tions packages carry warnings never to press it while using their programs. One magazine printed a letter sug- gesting that Apple users place a rub- ber grommet beneath the key, to make it harder to push. A software example of non-idiot-proofing is the Electric Pencil I's tendency to drop keystrokes entered by fast typists. The very point of word processing is to increase throughput; a program that drops keystrokes invokes paranoia in its users and slows them down. The use of "kill rings" is a nice, practical application of idiot-proof- ing. Deletions larger than single char- acters are not discarded, but stored temporarily in a stack. If text is deleted by accident, it can be re- trieved by a command. This truly protects users from themselves. Editors with kill rings actually make it difficult to lose text. Power versus Ease of Use In general, the more powerful a system is (i.e., the more capabilities it has), the more difficult it is to use. There are two reasons for this: first, the sheer number of commands makes them hard to remember; sec- ond, it becomes impossible to assign commands to keys or names in a con- sistent manner. Many editors have forty or more commands; for them, any single-key naming scheme soon collapses. Editors on the market to- day delete text at the keystrokes D (delete), G (gobble), W (wipe), and K (kill). Some compromise between power and ease of use is needed. Function keys are a liability for a powerful editor. Consider the Atex typesetting system, on which all func- tions are visible as function keys. There are, however, 32 function keys, and each can be prefixed with the shift key and/or a "supershift" key — making a total of 128 functions, assigned four to a key. Given the complexity of typesetting systems and the desire to provide an easy-to- use system, this end was inevitable. What is needed is a hierarchy of Circle 269 on inquiry card. » MICRO-SCI IS IN THE GAME FOR ALL THE APPLES... ^^■-♦^^C'V ...WITH A FULL E OF 5V4" DRIVES Micro-Sci has three disk drives and two controllers so you can configure your Apple II v or Apple ll Plus " system to fit your individual budget and performance requirements. THEFIHSTflCE— A2 The new A2 is the price/compatibility substitute for the Disk H,™ intended as the second drive on an existing controller, or as a full A2 subsystem. The A2 drive or A2 subsystem is an ideal choice when the drives will be primarily used for entertainment or prepackaged software programs. THE SECOND ACE— A40 The A40 is a price/performance alternative to the Disk II. With 40 tracks, you get an additional 20K bytes, and faster track-to-track access. The A40 is intended for use in dedicated DOS, CP/M and tions, an and draws tlmp r^ power directly from the MicroFazer you p*** ■<■«*«<** 9 * L volt, 300 mA power Ccffl C01Tll3LltG supply available where in W 1 j_ required). All this in while vou print. aW* package * *• 3.5 inches by 7 inches by 1 inch. Simple. And simply beautiful. At a price that won't faze you. Retail pricing for 8K model ($159); 16K ($189); 32K ($225); and 64K ($299). What we promise, we deliver. Micro- Fazer isn't somebody's idea of what an inex- pensive printer buffer shout* ' • Don't wait ~"~. Let #:■'■, :r'"- For further information and the name of your nearest dealer, call (404) 923-6666 or fill in this coupon and mail to: Guadram Corporation, 4357 Park Drive, Norcross, Georgia 30093; Name . Company „ Address __ City Title. .State. Zip, Circle 343 on inquiry card. Farewell to the Florida panther. J^^?j#^ -44sf^ :%-fcri-v-;* ■■mm #; •*:'■' tfdF No one knows how many Florida panthers are still alive. Perhaps fewer than 100. If these mountain lions die, another creature will be gone from the earth forever . . . the victim, first, of predator elimination pro- grams, and more recently, of ever-shrinking habitat. But we don't have to bid fare- -..;.' ' • well to the Florida panther. :..'"'• The National Wildlife Federation has awarded a grant to researchers '\y y \. to study the panther and its future . . . and to draw up a plan for saving it. That's just one small example of how the National Wildlife Federation is working to save endangered species from extinction. You can be a part of the effort. Join the National Wildlife Federation, Department,' 108,1412 16th Street, NW, Washington, DC 20036. IjPjgf 3 Great Memory Boards From S.C. Digital 'tfflOttHf -It'll llll Illlllllfflllllllfi 64K DYNAMIC RAM Uniselecf: 2' features: Model 64KUS • 1 6 or 24 bit address. • 8 bit data. • Bank select by SW settable port, bits in two blocks. • Two 32kb (128kb) addressing. • Transparent refresh - same as M:256KE. • Fast access time - 220nsec, will run with Z80, Z8000 to 4mhz, 8080, 8085, 8086, 8088 to 5mhz without Wait States. • Can be configured to various multiuser OS's. • Expandable to 256KB using 4164's. 256K DYNAMIC RAM features: Model 256KE • 16 or 24 bit address. • 8/16 bit wide data. • Transparent refresh with unlimited DMA, immune to Wait States, halts, resets. • Fast access time 180nsec from Smemr or Psync high, will run with Z80, Z8000 to 4mhz, 8080, 8085, 8086 to 8mhz without Wait States. • Accepts 4116, 4064's. Model Prices Assembled & Tested 256KE $795 256KB 256KE-128 S535 128KB 64KUS-128 $515 128KB 64KUS-64 $395 64KB(4164's) 64KUS $395 64KB(41l6's) 64KU-16 $285 16KB 32KUS $399 32KB 32KUS-16 $269 16KB 32KUS-N $149 No Memory 32KUS-B $ 72 Bare board with Doc 32 STATIC RAM 'Uniselect: 3' features: Model 32KUS • Fully Static using 2k by 8 NM0S chips. • 16 or 24 bit address. • 8/16 bit wide data. • Bank Select by port and bit in 32K block. • Two 16K block addressing with window capability in 2k increments. • EPR0M can be mixed with RAM. • Fast access - 250nsec from address valid - will run with Z80, Z8000 to 4mhz, 8080, 8085, 8088, 8086 or 68000 to 8mhz without Wait States. • Provision for Battery Backup using NM0S or CMOS. All boards conform to IEEE696/S100 specifications, fully socketed, legends, masks, Gold contacts. Guaranteed One Full year. Delivery is within 3 working days. MC, Visa or COD orders accepted. Illinois residents add 514 % sales tax. O.E.M. & DEALER PRICING AVAILABLE S.C. DIGITAL P.O. Box 906, Aurora, Illinois 60507 Phone (312) 897-7749 your preferred values each time you use the editor (this point is slightly less important if the editor has state save). Second, the people who created the editor have their own ideas about how they think an editor should work. You might not like some of them. Thus, you should be able to change the editor in a basic way. (Perhaps you'd like the StringSearch command to leave you at the end of the file if it can't find the string, in- stead of leaving you where you were when you gave the command.) To make this sort of change, you need access to at least a portion of the source code. This code must be well written so as to be easy to change, and there must be thorough docu- mentation so that whoever is actually making the changes can make them with a minimum of fuss. Final Note The list of features presented here is not the product of any one person's thinking. It was created item by item over a period of several years through the interaction of a large community of users, all of whom had their own ideas about what an editor should be like. These users were largely at the Massachusetts Institute of Tech- nology, and the editor that is the result of their ideas is called EMACS. Several versions of this editor exist: the original EMACS on DEC PDP-10 and DEC-20 computers, Multics EMACS on Honeywell Multics sys- tems, ZWEI on LISP machines, and MINCE on CP/M systems. ■ References 1. Finseth, Craig A. "Theory and Practice of Text Editors." MIT Laboratory for Com- puter Science Technical Memo 165. Cam- bridge, MA, June 1980. 2. Greenberg, Bernard S. "Multics EMACS: An Experiment in Computer Interaction." Proceedings, Fourth Annual Honeywell Software Conference, March 1980. 3. Mark of the Unicorn. MINCE User's Guide. Arlington, MA, October 1980. 4. Stallrman, Richard M. "EMACS: The Exten- sible, Customizable, Self-Documenting, Display Editor." MIT Artificial Intelligence Laboratory, A.I. Memo #519. Cambridge, MA, June 1979. 310 April 1982 © BYTE Publications Inc Circle 357 on inquiry card. Express yourself past check-in lines onTWA, With TWA's Round-Trip Check-In and Advance Seat Selection you can express yourself past check-in lines. Express yourself straight to the gate and. express yourself straight to your seat. It's easy with TWA's Airport Express. Nothing gets you past check-in lines and through the airport faster than TWA's Airport Expressf And that's because with TWA's Round-Trip Check-Inf Connection Check-In sm and Advance Seat Selection you can get boarding passes and seat assignments for your outbound, connect- ing and return flights before you depart. So on your trip home you can go straight to your seat on the plane. Instead of straight to the back of a check-in line. Next trip, ask for TWA's Airport Express. And express yourself past check-in lines. Call your travel agent, corporate travel department or TWA. Express yourself with the American Express® Card. Traveling is easy when you carry the American Express Card. Use it to charge your TWA tickets, car rentals, hotels, meals, theatre, shopping, almost anything you need while traveling. If you are not already a Cardmember, call toll-free 800-528-8000 for an application. The American Express Card. Don't leave home without it? Youre going to like Software Review Two Word Processors for North Star Edgar F. Coudal Coudal and Associates 627 South Crescent Ave. Park Ridge, IL 60068 Two new word processors for the North Star DOS (disk operating system) offer broad capabilities that rival the leader among CP/M word processors, Wordstar. Each sells for just under $500 and provides high- performance word processing, text editing, and print for- matting, although they take vastly different approaches to these tasks. In brief, the Benchmark word processor, from Metasoft, was seemingly designed for someone who needs retraining after every coffee break. There is a start- ing command menu, which branches at the touch of a key to six different subsystems (create, revise, view, print, merge, and disk procedures), and each subsystem has its own detailed menu. The user can enter a ? almost anywhere along the way and get two screens of concise command information. The other word processor, Lettergo, from Datek Systems Inc., provides one menu for disk operations and a 10-command print-formatting line at the top of the working screen. The remaining user information is con- tained in the manual, not the program. Both programs give a general-purpose computer (the North Star Horizon or another S-100 system) the power of a dedicated word processor costing $7500 to $15,000. (A dedicated system is one that performs one job well, but can't do anything else.) Of course, Benchmark or Let- tergo programs cannot be used simultaneously with other software (business, scientific, or recreational applica- tions), but they can be used sequentially. Upon order from the publisher or distributor, both Benchmark and Lettergo can be configured for various manufacturers' hardware or reconfigured to accom- At a Glance At a Glance Software Language Used Software Language Used Benchmark Assembler Lettergo Assembler Type Documentation Type Documentation Word processor 108-page loose-leaf manual Word processor 84-page loose-leaf manual, 26 pages devoted to begin- Manufacturer Audience Manufacturer ner tutorial, the rest to the Metasoft Corporation Secretarial, especially for of- Datek Systems inc. reference manual; appended 7\\ E. Cottonwood, Suite E fices with large volumes of 4786 Lee Highway 1 ]-page manual (same for- Casa Grande, AZ 85222 routine and repetitive material, such as \aw offices Arlington, VA 22207 mat] for MailMerj mailing-list program Price Price S499.95 $495 Audience Secretarial an6 general word- Format Format processing North Star DOS 5/4 -inch North Star DOS 5 # -inch double density and quad double density and quad density; North Star CP/M; density (CP/M 5/4 -inch and CP/M 2,2 8-inch single den- 8-inch coming) sity; Zenith Z-89; NEC PC-8000; Vector; Superbrain 312 April 1982 © BYTE Publications Inc Circle 184 on inquiry card. | Who in the world is Joe Larson? Joe is president of a computer software business. He has been, and still is, in the retail computer hardware business. It was here he recognized the need for more comprehensive software. Joe and his experienced staff developed a software system that is easy to use and understand. Software designed especially for small business accounting and management. Software that won't accept information that isn't logical. Software that takes advantage of the new, more powerful computers. Great Plains Software offers critical, indepth management information including profit by product, profit by salesperson, profit by customer and much more. What makes Joe Larson's Great Plains Software so different? The Great Plains Software system was created on a hardisk from the ground up for today's multiple uses and tomorrows business expansion. Some special features include a complete data base of every journal entry posted during the fiscal year. The ability to reverse or adjust entries in any general ledger account at any time during fiscal year... a CRT display of accounts payable and receivable..,the ability to display any customer or vendor records at a moments notice. The built-in password security system keeps company financial information completely confidential Get the most out of your computer investment. Ask your local computer store about the advantages of Great Plains Accounting Software or call (701)293-8483. Great Plains Software anticipates the future creating software for today and tomorrow. OVERALL - Password privacy system standard - Written in UCSD Pascal* - Hard disk oriented *TMUC Regents 5/L All entries on line entire fiscal year ■ Flexible format financial statements Comparative income statements VR Up to 9999 customers - Profit by customer, customer type, salesman and state Open item or balance forward Instant screen inquiry Automatically posts to G/L A/P - Up to 9999 vendors - Instant screen inquiry - Automatically posts to G/L PAYROLL - Up to 9999 employees - Up to 25 deductions per employee - Withholding computed - Prints W2, 941 & checks INVENTORY - FIFO, LIFO, standard cost, weighted moving average or serial number valuation - 5 price levels per part - Concise report including profit by part and line - Point of sale "cash register" program included GPS Great Plains Software Computer Center Building 123 15th Street North Fargo, N.D. 58102 (701)293-8483 3ae» * !! **^. MDBS: Superior Data Base Management for Application Developers Mainframe solutions at micro prices. MDBS solves the problem of expensive, time-consuming application development and maintenance. Here's what makes the MDBS Data Base Management System so unique: ECONOMY— Our state-of-the-art system cuts application development costs by up to 80% . HARDWARE COMPATIBILITY— From 8080, Z80...to the PDP-1 1 , MDBS delivers uniformly excellent results. PORTABILITY— MDBS operates under most popular oper- ating systems and languages, including CP/M, UNIX, IBM PCDOS, COBOL, BASIC, PASCAL, C, PLV1 , FORTRAN, and many more. INTEGRITY-RECOVERY, RESTART, and ROLLBACK techniques are available. Data base integrity is assured through advanced data structuring techniques. AUTHENTICITY— MDBS is the first and only true and com- plete DBMS currently available on microcomputers. CAPABILITY — Our system includes features you won't find anywhere else, at any price. • Fully-integrated, dictionary-driven. • Unparalleled data structuring ability— far superior to hierarchical, CODASYL, and relational approaches. • Powerful, English-like query system entirely non-navigation- al. Fully supports spur-of-the-moment "what if inquiries. • Query nesting allowed. Automatic sorting of output tables. • Built-in data security down to the field level plus advanced encryption capability. • Performance tuning, including the ability to influence physi- cal storage structures. • Multi-users capabilities including active and passive lockout. MDBS is not restricted to the limitations of data base "pretenders" like file management systems. To help make application development more effective and efficient, MDBS also offers extensive consulting services and professional training seminars. MDBS and other fine products are distributed in most countries through ISE. For more information please contact: Professionals know the difference. Mote: For more about ISE see page 127 ] Please call me immediately at ( ISE-USA P.O. Box 248 Lafayette, Indiana 47902 Tel: (31 7) 463-2581 ISE-ADV/ORGA GERMANY Lipowskystr. 26 8000 Munich 70 Tel: (089) 776 023-4 ISE-PACTEL Rochester House 33 Greycoat Street London SW1P2QF Tel: 01-828 7744 1SE-CEGOS Tour Chenonceaux 204, Rond-Point du Pont de Sevres 92516 Boulogne Billancourt Cedex Tel: 620-61-04 ISE-ADV/ORGA SWITZERLAND Mainaustraf>e 1 7 CH-8008 Zurich Tel: (01) 32 02 70-1 Elsewhere: ISE-INTERNATIONAL P.O. Box 248 Lafayette, Indiana 47902 Tel: (317)463-2581 (phone no.) » D Please tell me about your half-day seminar D Please tell me about your three-day workshop □ I'm enclosing $95 in payment for the MBDS manual ($125 over- seas; Indiana residents please add $3.40 sales tax) D Please charge to my VISA or MasterCard Card Number- _Phone No._ -Expiration Date -Title- .State _Zip_ Phone (area code) MAIL TO: ISE P.O. Box 248 Lafayette, IN 47902 Lettergo Y N N 1 N N Y Y Y Y Y Y Y N Y Y Y Y Y Y N Y Y Y Y Y 4 Y Y Y Y 78 Y Y 5 Y ? Y Y Y Y Y Y Y Y Y Y Miscellaneous Features: Attach phrases of 2000 words to a single key Y N Notes: 1. Next page 2. Delete to end of line 3. Delete entire line 4. Force end of page 5. Eight positions, including alternate sides 6. "Shadow" print, darker than bold Table 1: Comparison of the features of Benchmark and Let- tergo. "Y" stands for Yes and "N" for No. Editing: B enchm Cursor movement bottom of document Y next block or paragraph N next screen Y 1 next sentence Y next word Y top of document Y up, down, right, left Y Copy block Y Copy from another file Y Delete block Y character Y Find text Y Find and replace (once) Y Find and replace (all occurrences) Y 'Help' screen or aid Y Insert block Y character Y Move block Y Video display change margins Y change tabs Y Printing: Justification left justified Y left ragged N right justified Y right ragged Y Line spacing set to single or double Y set to triple or more Y Page layout go to new page Y set bottom margin Y set indentation Y set right and left margins Y set top margin Y maximum characters per line 155 Page numbering basic Y varying position or format Y Printer control allows pause for positioning form Y print draft copy Y feed single sheets Y bidirectional printing Y Text variations bold face Y 6 centering Y columnar output Y footers Y headers Y subscripts Y superscripts Y underlining Y All features changeable in middle of document Y modate user changes in hardware. Review copies of each system came ready to run on my double-density North Star and were configured to accommodate my Soroc 120 terminal and Diablo 1610 printer. All I had to do was boot, load, and edit. The Lettergo system is designed to work on a variety of different terminals, printers, and Z80-based computers. The manual has detailed instruc- tions for such printers as the NEC 5500, Diablo 1610/1620, and Anadex 9500/01, and for such terminals as the TVI-900, ACT-V, and Hazeltine 1500. Datek con- figures, the software for a particular user's hardware. The Benchmark system arrives as a 'configurator disk," which produces a data disk and a program disk. The con- figuration disk allows the user to configure Benchmark for various hardware, including Diablo, NEC, TI, Cen- tronics, and Qume printers, and Soroc, Hazeltine, Heath, Televideo, Adds Regent, IMS WP, and Tandy II ter- minals. After seeing these two systems in action and using them almost interchangeably for a couple of months, I have the same complaints about both, but they are com- plaints that extend to many other word processors as well. First, neither shows right-hand justification on the screen, leaving it up to you to imagine what the printed text will look like. Second, neither will spool-print, which means that printing a long manuscript with my relatively slow Diablo can occupy the computer for a long time. NOW WITH TMS 991 8A SINGLE BOARD COLOR VIDEO AND SOUND GENERATOR KIT $350* COLOR VIDEO KIT $320* 'STANDARD KIT INCLUDES TMS 9918, ADD $25 FOR TMS 9918A. COLOR VIDEO PROCESSOR • Text, Graphics, Animation • 16 Colors • 256x192 Reso- lution • NTSC Composite Video Output • Uses TMS 9918 • Includes I/O Mapped 16K Video Memory • 3D Simulation with 32 Video Sprites • 2 Byte X-Y Positioning • Real Time Clock • 8 Level Interrupt Selection • Inexpensive RF Mod- ulator allows easy connection to any color TV • Video over Video and Extended Graphics II Mode with TMS 991 8A • PROGRAMMABLE SOUND GENERATOR • Music, Sound Effects, ToneSignaling, Ultrasonics • 27 Hz to 111 KHz Range • 3 Programmable Analog Channels with Separate Frequency, Volume and White Noise Control • 10 Selectable Envelope Wave Shapes under Software Control • Two 8-Bit Programmable I/O Ports for use as External Keyboard/Display Interface • Power Amplifier fordriving External Speaker • Texas residents add 5% sales tax. Prices include complete documentation with programming examples PC board is solder-masked with gold contacts. Add $100 for assembled and tested units. Send $14.50 for 120 page manual, refundable with order. Compatible with Z80, 8085 and 8080 at 2 or 4 MHz on S-100 buss. CT|A ELECTRONIC DESIGN ASSOCIATES *-**** P.O. Box 94055 Houston, Texas 77018 (713) 999-2255 Circle 467 on inquiry card. Circle 167 on inquiry card. April 1982 © BYTE Publications Inc 315 PROTEUS: a totally new concept in 16 bit microcomputer systems Package price includes; 5 1 /4" Floppy Drive (Double density 80 track), 320 K formatted, Systems Software (Bi-Terminal operating system), Terminal Configurator, Pro-basic converter, CP/M File Handler^ Microsoft Basic -8000 (Not included are terminals & printers). F.O.B.- Factory A powerful, compact 2-user system that can be expanded to any capacity you require Proteus is the first-ever 16-bit single board micro- computer, based on the Z8001 microprocessor. It offers 128K of dynamic RAM for user memory, three serial ports, one parallel port and a real time clock. It can be used in conjunction with existing terminals and printers... providing a remarkably fast and powerful system for two separate users. But that's only the beginning . . . because Proteus is also the central module in a system you can expand to meet your future needs! lET's exclusive design allows up to 256 Proteus modules to be linked... to provide simultaneous access to 512 users, with no loss in speed or mem- ory capacity for the individual user. The basic 2- user system is available at surprisingly low cost . . . and you'll save even more in the future by adding toyourProteussystem,ratherthan buying new equipment. Grow with Proteus — the micro- computer system of the future! For a complete information package, write: Innovative Electronics "Technology Ltd. P.O. Box 5188, Vancouver; B.C., Canada V6B 4B5 Tel. (604) 430-5166 Telex: 04-356776 IET HO VCR 316 April 1982 © BYTE Publications Inc Circle 207 on inquiry card. One other complaint is the excess of riches. With either system, you can direct the printer to overstrike, boldface, and underline simultaneously . This may be useful for someone drafting legislation or revising a contract, but it seems like overkill; the added complexity gets in the way. Although both Benchmark and Lettergo were designed with the same mass market in mind— the high-production office secretary— each reflects its origins. Benchmark (ac- cording to distributor R & B Computers, of Tempe, Ari- zona) originated in a lawyer's office, and certain func- tions, capabilities, and examples in the manual reflect that background. Lettergo, on the other hand, was writ- ten by Gregory Heise, owner of a computer shop and a high-class hacker of long standing. Heise had watched many novices struggle with unnecessary complication and poor documentation and, as a result, tried to simplify Lettergo as much as possible. Both word processors do everything that leading word processors should do: automatic line wraparound on in- put, block moves, global search and replace, right- margin justification, automatic pagination, automatic headings and footings, underscoring, subscripting and superscripting, and so on (see table 1). Both can generate personalized form letters with their merge capabilities. Benchmark uses either an internal pat- tern/letter, keying in the necessary changes from the ter- minal, or a letter and mail list generated by a separate software package, Mail List, which is a list manager with print capability (suggested retail, $399). Lettergo uses a BASIC language MailMerj program, which is included on the word-processing disk, to produce form letters. Word-processing packages have evolved to the point where certain specific features — many of them mentioned above — should be taken for granted. When considering a new package, the prospective user should ask, "What can it do that's really useful that the others can't?" and "How easy is it to learn, use, and adapt?" Benchmark Designed for use by someone "who doesn't know a byte from a bite," Benchmark merits praise for the time and effort that went into its menus and safeguards. One of the processor's features is that it does not use control characters, except on the least capable of terminals. To instruct the processor to do something, the user enters the command mode and hits a single key: F for Finish, I for Insert, J for Jump to a page, D for Delete, and so on. When you use a command that can make irretrievable changes, such as killing a document or quitting at the wrong place, Benchmark asks if you really mean it. And if you do, you must hit the Rub or Execute key. Benchmark's Hallmarks Now, for the especially nice things about Benchmark. It automatically maintains a remarkably detailed direc- tory of what is on the data disks, including titles of up to 30 characters, initials of the author of each document and the operator of the system at the time the document was produced, time and date of last revision, number of K NEECO WHY BUY FROM THE BEST? Service.. . Support... Software . . . MULTI-CLUSTER For Commodore Systems, allows 3 CPUs (Expandable to 8) to access a single Commodore Disk. MULTI-CLUSTER (3 CPU's) $ 795 Each Additional CPU (up to 8) . . . S 199 EPSON PRINTERS MX-60 PRINTER $ 645 MX-80 FT $ 745 MX-100 $ 945 MX-70 $ 459 INTERFACE CARDS 8141 (RS-232) $ 75 8150 (2K Buffered RS-232) $ 150 8161 (IEEE 488) $ 55 8131 (Apple Card) $ 85 8230 (Apple Card) $ 25 8220 {TRS-80 Cable) $ 35 DIABLO 630 PRINTER DIABLO 630 - Serial - RS-232 $2710 Tractor Option $ 250 Qpi commodore 16K B {16K RAM-40 Column) - Lim. Qty $ 995 32K B (32K RAM-40 Clm.) - Lim. Qty $1295 4016 (16K RAM 4.0 Basic-40 Clm.) $ 995 4032 (32K RAM 4.0 Basic-40 Clm.) $1295 8032 (32K RAM 4.0 Basic-80 Clm.) $1495 8050 Dual Disk (1 Meg Storage) $1795 4040 Dual Disk (343K Storage) $1295 8010 IEEE Modem $ 280 C2N Cassette Drive . . $ 95 CBM - IEEE Interface Cable . . . . . $ 40 IEEE - IEEE Interface Cable $ 50 VIC 20 Home/Personal Computer $ 295 CALL NEECO FOR ANY OF YOUR COMMODORE COMPUTER NEEDS NEC SPINWRITER PRINTERS 5530 (Parallel) $3055 5510 (Serial) $3055 5520 (KSR-Serial) $3415 Tractor Option $ 225 APPLE 16K APPLE IK $1330 32K APPLE Ik $1430 48K APPLE IK $1530 APPLE DISK w/3.3 DOS .$ 650 APPLE DRIVE Only $490 APPLE III 128K - In Stock! w/Monitor + Info Analystpak $4740 AMDEK MONITORS INTERTEC COMPUTERS Video 100 12" B+W $ 179 Video 300 12" Green $ 249 Color 1 13" Low Res $ 449 Color II 13" High Res $ 999 64K Superbrain (360 Disk Storage), CP/M™ . . . $3495 64K QD Superbrain (700K Disk Storage), CP/M™. . $3995 *CP/M is a registered trademark of Digital Research ATARI COMPUTERS Atari 400 (16K RAM) $ 399 Atari 800 (32K RAM) - good thru 8/31 $1080 Atari 410 RECORDER $ 89.95 Atari 810 DISK DRIVE $ 599.95 NEECO carries all available ATARI Software and Peripherals. PROFESSIONAL SOFTWARE WordPro 1 8K WordPro 3 (40 Clm. )16K WordPro 3+ WordPro 4 (80 Clm.) 32K WordPro 4+ $ 29.95 $ 199.95 $ 295 $ 375 $ 450 JUST A SAMPLE OF THE MANY PRODUCTS WE CARRY, CALL US FOR OUR NEW 60-PAGE CATALOG. WE WILL MATCH SOME ADVERTISED PRICES ON CERTAIN PRODUCTS USTED UNDER SIMILAR "IN STOCK" CONDITIONS. NEECO 679 HIGHLAND AVE. NEEDHAM. MA 02194 (617)449-1760 Telex: 951021 MON-FRt 9:00 - 5:00 V/SA MasterCharge and VISA Accepted Circle 295 on inquiry card. BYTE April 1982 317 bytes of disk space used by each document, a running total of the amount of disk space used, and a warning when a disk is getting full. All together, this can be a super filing system. And once the user knows the system, he or she can bypass all the menus and prompts. (The literature claims that the entire system can be learned in one day, but real facility takes longer.) Printed line length of up to 155 characters is supported, which is useful for spread sheets and other financial documents. Cursor control includes nine movements: left, right, up, down, home, next word, first character next line, first line any page, and next screen of text. Finally, the best for last: a simple set of commands allows the user to attach up to 52 separate "phrases" to single-letter keys. Each phrase can be up to 2000 characters long, and it can be called and inserted at the cursor position with the preset key. This is an excellent feature for repetitive jobs involving such projects as legal documents and form letters. It's hard to understand why Metasoft doesn't place more emphasis on this feature. On the less positive side, Benchmark operates with a program disk and a data disk, using two drives. (Files can be saved to the program disk, but there isn't much room there.) The program is disk buffered, text is read into RAM (random-access read /write memory), then sent to the printer. With my North Star system, which has 56K bytes of memory, the drives are constantly active on long Unravel the complexities of Medical Data Management. MED2000 is the complete medical data management system. MED 2000 can handle a comprehensive array of tasks j from billing, insurance form preparation and financial summary reporting to medical records processing appointment scheduling and word processing. Designed as an integral part of MED2000, the word processing package is directly interactive with the medical data base and features an electronic medical dictionary. MED2000 is designed for use on a 8080/ Z80 micro- computer with 80x24 CRT and 8" disks. The package is available by itself or as part of a complete hardware/ software package. MED 2000 runs in either single or multi- user (CPM/MPM) environ- ments. Use of rigid disk technology is recommended but not required. A brochure is available on request. Dealer inquiries invited. WIMI2000 the Complete Medical Management System TransOhio Building 1640 Franklin Ave. Kent, Ohio 44240 216/678-5202 *CPM/MPM are registered trademarks of Digital Research documents and that slows the printing process. Metasoft comments that "64K is nice'' for long documents. Another drawback is that simply having all those menus tends to make the user reliant on them, and as a result slows use of the program. This is probably not a legitimate complaint for an office situation where a secretary is running hard for four or five hours a day and uses the facilities and capabilities until they become sec- ond nature, but it can be a problem for those who spend most of their time creating text and very little time for- matting and printing. Finally, as noted earlier, Benchmark provides no spool printing or on-screen right justification. Lettergo If Benchmark is the high-performance secretary's ultimate weapon, then Lettergo is for users who rely on a word processor, but not necessarily for high volumes of routine work. Lettergo has one menu, disk-operation commands — and that's it. The menu is so spartan (Save, Load, Directory, Kill, Quit, Merge, and Free) that Heise used part of it for the copyright. The Control key gets a workout on the Lettergo system because Lettergo uses control characters for editing func- tions (Control B returns the cursor to the beginning of the document, Control E scrolls toward the end, Control X reverses scrolls, Control P starts output to the printer from the cursor location; and so on, through all the let- ters of the alphabet). Even after using Lettergo exten- sively, I'd hate to take a test on the functions of all the keys. About 99 percent of the work can be performed with fewer than half of the control keys, so the demands on human memory are not as great as they seem. Lettergo's Goodies For all its versatility, Lettergo is remarkably easy to learn and operate. While Heise's excellent manual does not make any untoward claims about ease of learning, my wife, when faced with the sudden realization that a truly massive work she'd undertaken would require at least one full rewrite and a final retype, learned to use Lettergo (with no previous computer experience) in one long afternoon. Although simple and chatty, the manual doesn't talk down to the user. It presumes virtually no previous com- puter knowledge and is a basic, step-by-step tutorial, followed by a complete reference manual that expands on the first section, and concluding with a section on how to set up the various types of hardware that can be used with Lettergo. Lettergo drives the printer from system memory, rather than off the disk, which means that print speed is limited only by the speed of the printer. And the system makes it easy to format for printing by providing a for- mat line across the top of each text screen. The line con- tains 10 single letters followed by two numbers each, so that a maximum of 30 characters provides full control over what the printer will produce. The formatting com- mands include L for line length, P for lines to a page, and 318 April 1982 © BYTE Publications Inc Circle 456 on inquiry card. When youJL_ compare value in low-cost terminals, there's no comparison. Hazeltine ADDS Televideo Feature Esprit™ Viewpoint TVI-910 Screen Matrix 7 x11 5x8 8x 10 Display set 128 96 96 Keyboard Numeric pad 14 keys 11 keys 14 keys Function keys 14 3 10 Display color Green White Green Operation Horizontal tabs Yes No Yes Insert/Delete Yes No No Page mode Yes No No Transmit field Yes No No Buffered Yes No No Warranty * 90 days 90 days Hazeltine Esprit, ADDS Viewpoint and the Televideo TVI-910 are all competitively priced at the low end of the market. Esprit is at the high end in value. ''Hazeltine, in cooperation with Western Union, offers two warranty options, effective on Esprit terminals purchased after February 1, 1982, for service rendered through December 31, 1982: 1. Return to factory for repair at no cost for materials and labor. 2. On-site service contract through 1982 in any Western Union Zone 1 area for a one time charge of only $49.95 per terminal For more information call your local distributor, or Hazeltine Corporation Computer Terminal Equipment Greenlawn, NY 11740 National Sales: (516) 549-8800 Telex: 96-1435 For additional sates office locations, please call our toll-free number: (800) 645-5300. Esprit by Hazeltine An editing terminal at a conversational price. Circle 462 on inquiry card. S for line spacing — an arrangement that is quick and easy to use. Any of the formatting commands can be changed at any time or any place in the document, through the use of dot commands — a period at the left margin, followed by the letter indicating which formatting command is to be changed. For instance, .L78-58 will shorten the line length of text following the command by 20 characters, while .L58-78 will return the text to the original length. This is not a unique system, but many word processors do not show the changes on the screen, as Lettergo does. If a revised file is longer than the space allotted for the original version of the file, Lettergo will save the new ver- sion further along on the disk and kill the original, without telling the user. When disk capacity is reached, the program will automatically compact the disk (rewrite all the disk files in a contiguous manner), thus eliminating all those holes along the way. The user can control this housekeeping if he or she wants, though Heise did not in- clude the command in the disk-operations menu. (Nor did he include the information that you can direct output to devices other than the video display or printer, though that capability is provided in a single control character from the disk menu. This capability is handy if you have a homebrew spooler sitting around in high memory, disguised as another device.) Among the disadvantages of Lettergo are that two operations are necessary to move a block of type: one to move it to the new location, the second to kill the block at the old location. A command that automatically deletes at the old location while moving to the new loca- tion would be more useful. Heise describes the two-step operation as a safeguard. Another drawback is that maximum output line length is 78 characters. If you are printing at a pitch of 12 characters per inch, that is a bit restricting. Most finan- cial documents are too wide for Lettergo. Finally, as noted earlier, Lettergo has no spooling capability and no on-screen right-hand justification. Conclusions These two systems provide truly flexible, powerful, and complete screen-oriented word processing, something that was previously unavailable to the North Star DOS user. The prices are not excessive (each costs $500), considering the word-processing power that these software packages provide, and each system has advan- tages for different users. Benchmark is beautifully suited to the office environment, while Lettergo can serve in the office provided there is no need for wide margins. It is even more useful in such word-processing applications as freelance writing. Neither demands much computer knowledge beyond knowing how to turn on the machine, and both have been thoroughly tested in working environments: Bench- mark in legal applications and Lettergo in government offices. Field proof is important in a time when some high-priced software does not deliver anywhere near what is promised. Both of these systems do.B PRODUCTS FOR YOUR RADIO SHACK w >N*- MICROTEXT COMMUNICATIONS VIA YOUR MODEM! Now you can use your printer with your modem! Your computer can be an intelligent printing terminal. Talk to timeshare services or to other personal computers; print simultaneously through a second printer port; and re-display text stored in memory. Download text to Basic programs; dump to a cassette tape, or printer, or both. Microtext can be used with any printer or no printer at all. It features user-configurable duplex/parity for special applications, and can send any ASCII character. You'll find many uses for this general purpose module! Available in ROMPACK, ready-to-use, for $59.95. SOFTWARE DEVELOPMENT SYSTEM The Micro Works Software Development System (SDS80C) is a complete 6809 editor, assembler and monitor package contained in one Color Computer program pack! Vastly superior to RAM -based assemblers/editors, the SDS80C is non- volatile, meaning that if your application program bombs, it can't destroy your editor/assembler. Plus it leaves almost all of 16K or 32K RAM free for wur program. Since all three programs, editor, assembler and monitor are co-resident, we eliminate tedious program loading when going back and forth from editing to assembly and debugging! The powerful screen-oriented Editor features finds, changes, moves, copys and much more. All keys have convenient auto repeat (typamatic), and since no line numbers are required, the full width of the screen may be used to generate well commented code. The Assembler features all of the following: complete 6809 instruction set; complete 6800 set supported for cross-assembly; conditional assembly; local labels; assembly to cassette tape or to memory; listing to screen or printer; and mnemonic error codes instead of numbers. The versatile ABUG monitor is a compact version of CBUG, tailored for debugging programs generated by the Assembler and Editor. It features examine/chanae or memory or registers, cassette load and save, breakpoints and more. SDS80C Price: $89.95 THE mi mi mi im+» GAMES Star Blaster — Blast your way through an asteroid field in this action-packed Hi-Res graphics game! Available in ROMPACK; requires 16K. Price: $39.95 Pac Attack — Try your hand at this challenging game by Computerware, with fantastic graphics, sound and action! Cassette requires 16K. Price: $24.95 Berserk — Have fun zapping robots with this Hi-Res game by Mark Data Products. Cassette requires 16K. Price: $24.95 Adventure — Black Sanctum and Caiixto Island by Mark Data Products. Each cassette requires 16K. Price: $19.95 each. R0MLESS PAK I — is an empty program pack capable of holding two 2716 or 2732 EPROMs, allowing you up to 8K of program! The PC board inside comes with sockets installed, ready to go with the addition of your custom EPROMs. Price: $24.95 2-PASS DISASSEMBLER — with documentation package. 16K; cassette. 80C Disassembler Price: $49.95 CBUG — Machine language monitor. CBUG Cassette Price: $29.95 CBUG ON 2716 EPR0M: Can plug into Romless Pak I. CBUG ROM Price: $39.95 PARALLEL PRINTER INTERFACE — serial to parallel converter allows use of all standard parallel printers. P180C Price: $69.95 Assembly Language Programming, by Lance Leventhal. Price: $16.95 MEMORY UPGRADE KITS: 4-1 6K Kit Price $39.95. 16-32K (requires soldering experience) Price: $39.95 PARTS & SERVICES: SAMs, 6809ES, RAMs, PIAs. Call for prices. T „ r ~ ^ r-. ~ <^m»— WE SHIP FROM STOCK! ■/M\0©U§© lm^ GOODSTUFF! Master Charge/Visa and COD Accepted W®\^%& P.O. BOX 1110 DEL MAR, CA 92014 714-942-2400 320 April 1982 © BYTE Publications Inc Circle 270 on inquiry card. Now NRI takes you inside the new TRS-80 Model III microcomputer to train you at home as the : new breed oiiomputer specialist! NRI teams up with Radio Shack advanced technology to teach you how to use, program and service state-of-the-art microcomputers... It's no longer enough to be just a programmer or a technician. With microcomputers moving into the fabric of our lives (over 250,000 of the TRS-80™ alone have been sold), interdisciplinary skills are demanded. And NRI can prepare you with the first course of its kind, covering the complete world of the microcomputer. Learn At Home in Your Spare Time With NRI training, the program- mer gains practical knowledge of hard- ware, enabling him to design simpler, Training includes new TRS-80 Model HI micro- computer, 6-fu nction LCD Beckman multimeter, and the NRI Discovery Lab with hundreds of tests and experiments. (TRS-80 is a trademark of the Radio Shack division of Tandy Corp.) more effective programs. And, with ad- vanced programming skills, the techni- cian can test and debug systems quickly and easily Only NRI gives you both kinds of training with the convenience of home study No classroom pressures, no night school, no gasoline wasted. You learn at your convenience, at your own pace. Yet you're always backed by the NRI staff and your instructor, answering questions, giving you guidance, and available for special help if you need it. You Get Your Own Computer to Learn On and Keep NRI training is hands-on train- ing, with practical experiments and demonstrations as the very foundation of your knowledge. You don't just pro- gram your computer, you go inside it. . .watch how circuits interact. . . inter- face with other systems. . .gain a real insight into its nature. You also work with an advanced liquid crystal display hand-held multi- meter and the NRI Discovery Lab, per- forming over 60 separate experiments. You leam troubleshooting procedures and gain greater understanding of the information. Both microcomputer and equipment come as part of your training for you to use and keep. Send for Free Catalog. . . No Salesman Will Call Get all the details on this exciting course in NRI's free, 100-page catalog. It shows all equipment, lesson outlines, and facts on other electronics courses such as Complete Communications with CB, TV/Audio and Video, Digital Elec- tronics, and more. Send today, no salesman will ever bother you. Keep up with the latest technology as you learn on the latest model of the world's most popular computer. If card has been used, write to: NRI Schools McGraw-Hill Continuing Education Center . 3939 Wisconsin Avenue ■ ■fill Washington, D.C. 20016. We'll train you for the good jobs! A Disk Operating System for FORTH An in-depth look at how a DOS operates Peter Reece 152 Hillcrest Ave. Dundas, Ontario Canada L9H 4Y2 A disk operating system (DOS) is the heart of any computer system. Without a powerful and easy-to-use DOS, creating and maintaining pro- grams and data on the system can be cumbersome if not impossible. This is because the DOS offers utilities of various types which manipulate files and, in general, perform all of the "housekeeping" chores essential to the system's smooth operation. In ad- dition, most DOSes attempt to be user-friendly. That is, they are designed to make operation of the computer as simple and foolproof as possible. This article describes the creation of a DOS for the FORTH language. FORTH is powerful, but it lacks a DOS in the usual sense. That is, it does not come with utilities to handle the normal operating-system con- structs common in computer systems. For example, no options are available to have named files, to query disk space, to run named programs, and so on. The DOS described here, ap- propriately called FORTHDOS, allows creating and deleting named files, maintaining directories of named files, listing statistics on disk usage, generating files by type (se- quential, random, or block), listing files, allocating disk space, adding named utilities, getting help with commands, write-protecting any disk or file area, file copying, giving error messages, and many other features. FORTHDOS is a powerful, efficient, and easy-to-use DOS for single-user FORTH systems. A complete listing of FORTHDOS is given in listing 1. Before discussing this listing, however, let's look at some of the rationale involved in pro- ducing this or, for that matter, any DOS. FORTHDOS is a powerful, efficient, and easy-to-use DOS for single-user FORTH systems. Features of DOS Packages All DOSes contain * commands for file manipulation. These commands usually invoke primitive operations or "primitives" responsible for: se- quential and random-access file con- trol, commands for creation and dele- tion of files, file space allocation algorithms, and similar types of file access controls. Another class of DOS commands contains commands descriptive in nature and used mainly to display in- formation. Examples of this class are those which list a directory of system or user files, show the system status, generate file listings, or alter the write- or security-protection status of files. A third class of DOS commands concerns program control. These commands are exemplified by com- piler calls (the compiler calls the DOS to determine how and where to place compiled files) and by commands allowing you to add primitives to your own software or even to add your own pseudo-DOS commands. An example of the latter is in the CP/M disk-operating system, which allows you to create custom com- mands via the use of .COM files. A final class of DOS functions con- sists of utilities. While not strictly part of the DOS structure itself, utilities are often available as part of a DOS package. For example, a file copy utility such as PIP in CP/M or COPY in TRSDOS may be con- sidered as a separate class of DOS commands. Table 1 lists by command class FORTHDOS features usually found in typical DOS packages. Note that all of the common commands, rang- ing from creating a file to allocating disk storage space for random access, are available in FORTHDOS. As this article will discuss, all of these com- mands depend ultimately on a very simple structure — the bit map and the primitives that manipulate it. 322 April 1982 © BYTE Publications Inc Circle 438 on inquiry card. $ 1295 for a 40 CPS Word Processing Printer? C. ITOH F-10 Printmaster 40 CPS Daisy Wheel Printer IS THIS THE C. ITOH STARWRITER III? The C. ITOH F-10 Printer is manufactured by Tokyo Electric Co., Ltd., (TEC), the same company that made the 25 CPS Starwriter ), and the 45 CPS Starwriter II, and you may even see other people calling it the Star- writer III, TEC 40 CPS, or just simply C. ITOH 40 CPS Printer. By any name this may be the best word pro- cessing printer value on the market today. When you compare the standard features with any printer on the market today, we think you will agree. INDUSTRY STANDARD FEATURES Plug compatible with Diablo, Qume, and NEC Printers. Uses standard 96 character plastic print wheels, and the new dual-plastic print wheels that, unlike metal wheels, provide superior print quality over the entire print life of the wheel. Software control characters that are standard for all major word processing packages. CONSTRUCTION Built on a cast aluminum base with high quality metal parts, the unit stands just 6" high, yet will feed paper from the bottom as well as the rear. The solid construc- tion makes the unit low noise and ideal for office or home. INTERFACE RS 232-C interface with XON/OFF and ETX/ACK protocols. Baud rate selectable to 1200 Baud. APPLICATIONS Compatible for use with Apple, Radio Shack, IBM, NEC, Xerox, Vector Graphics, North Star, Altos, etc. OPTIONS Bi-directional tractor feed, printer stand. SPECIFICATIONS Print Speed Character Spacing Line Spacing Paper Width Print Wheel Ribbon Interface Dimensions Weight Power Requirements Reliability Data 40 CPS 1/120" (minimum) 1/48" (minimum) 16" (maximum) Industry standard 96 character wheel Multi-strike, or fabric cassette RS 232-C 22.5"Wx 15.9"Dx6"H 30.8 pounds 115V±10%, 50/60 Hz, 70W MTBF is 1year with a 75% duty cycle WARRANTY 90 day factory warranty. We pay shipping both ways. SATISFACTION GUARANTEED If, for any reason, you are not satisfied, you may return the unit to us within 30 days for a full refund. SHIPPED BY UPS Prepaid or COD by money order or cashiers check. Prices quoted are for stock on hand and are subject to change without notice. yufrite ww *Mfriter, inc. 1703 Stewart Street, Santa Monica, CA 90404 TO ORDER OR FOR INFORMATION, CALL: (213) 829-6871 Class 1: File Manipulation WBLK RBLK MAKE READ WRITE RREAD RWRITE MOUNT REMOVE — Primitive to write a record. This primitive contains machine-language code to access a given sector from a given track on a given drive. (System specific.) — The read-record primitive corresponding to WBLK. — Primitive to enter/create a file in the directory. — Primitive to perform a sequential-access file read. — Performs a sequential-access write to a file. —Primitive to perform a random-access file read. — Performs a random-access file write. — Loads a disk directory into RAM. — Writes a disk directory from system RAM to disk. Class 2: Examples of Informative Commands FREE — Reports on disk and RAM space used/remaining. HELP — Lists information on DOS commands and their uses. FSIZE — Reports on the size and status of any file. FILES — Types a full directory of the disk plus relevant information. BLOCKS — Types a list of all records active for a given file. Class 3: Examples of Commands for Program Control NAME — Enters a file name into the DOS for future use. RUN — Compiles and executes a program. LOOKUP — Checks to see if a given file name is on disk. COPYALL — Copies a file to another file from a program. DINIT — Initializes a new directory. PROT? — Sees if a given file is write-protected. DPUTNM — Saves a given file name into a directory. KILL — Deletes a file under program control. Class 4: Examples of DOS utilities FCOPY — Copies a file to another (old/new) file. XCOPY —Like FCOPY but copies to a non-current disk. BCOPY — Copies records grouped by contiguous record numbers. PROTECT — Declares a file as write-protected. UNPROTECT — Declares a file to be read/write accessible. TYPE — Types a file to the console device. PTYPE — Prompts for format information, then prints on printer. RENAME — Gives a new name to an old file. ASSIGN — Forces DOS to assign a given record number to a file. LOCK — Prevents DOS from accessing read/write a record number. KILL — Deletes a file from the directory. TIME — Prints current time of day. TIMESET —Sets time of day. Table 1: FORTHDOS commands divided into classes of commands found in typical DOSes. Bit Maps Although a DOS designer has many strategies to choose from in set- ting up a system, almost all DOSes use a bit map approach to regulating file activity on a disk. A bit map is a small byte array in which each bit represents the smallest logical group- ing of bytes on a disk. Such a group- ing is typically called a record or, in a FORTH-based system, a block. Suppose we are designing a DOS using a SV^-inch, 35-track disk. We could format this disk in many ways (by writing EOR or end-of-record marks onto the disk). We might use the TRSDOS scheme where EOR marks are written to yield a record size of 256 bytes or one record per sector. Since there are 35 tracks per disk and 10 records per sector, this equals 350 records per disk contain- ing 350 times 256 or 89,600 bytes of storage. We now need some scheme for keeping track of whether or not a given record is available for use, or if it is part of an existing user file. If we used the TRSDOS scheme mentioned above, a simple way to do this would be to create a bit map 350 bits long (just under 45 bytes) in which the first (high-order) bit represents the first record on the disk and the last (low- order) bit represents the last (350th) record on the disk. If a given record were in use, we would set the ap- propriate bit in the bit map to 1; otherwise we would set the bit to 0. This simple scheme would allow a DOS to keep track of all available records. Notice that since only a small amount of storage would be necessary (45 bytes), the entire activi- ty of the disk could easily fit into free memory in a section reserved for sys- tem use. We will use a modified ver- sion of this scheme based on the tradi- tional unit of storage in FORTH, the block. In FORTHDOS, since records (blocks) are 1024 bytes long, a 35-track disk having 89,600 bytes of storage would require only 11 bytes of storage plus 1 bit (1 bit represents 1024 bytes): 11 bytes X 8 bits per byte + 1 bit «* 89 blocks per disk In practice, this value is actually 86 blocks per disk, since a formatted disk has fewer available bytes for data than does the unformatted disk described above. This means that 11 bytes are easily enough to contain in- formation on every data record available to the user. Figure 1 shows how FORTHDOS uses this simple scheme to map disk activity. Having developed this scheme of mapping record activity on the disk (given a specific disk format), we now need to develop a method of mapping file ac- tivity (i.e., activity of groups of records). Bit Maps for User Files Once we have settled on a format for each disk, we must determine whether or not to allow a file to use all records on the disk if they are available. This will determine the length of a file's bit map. If we refer again to the 35-track disk formatted as discussed above, a possible 86 blocks are available for use by any one file. For simplicity, let's allow files to be 86 blocks long. This would mean that, like the disk activity bit map, each file bit map would be 11 324 April 1982 © BYTE Publications Inc The Lightning One 8086/8087/8089 CPU Board Features: □ 4, 5, 8 or 10 MHz operation jumper selectable □ 8086 or 8088 main processor □ Independent I/O and memory waitstate generator □ Up to 16K bytes of onboard EPROM D 9 vectored interrupts expandable to 65 □ EPROM monitor with diagnostics and disk utilities □ 8087 and 8089 co-processors available onboard □ CP/M-86* and MS-DOS** software support * CP/M-86 is a trademark of Digital Research. **MS-DOS is a trademark of Microsoft. Lightning One is a trademark of Lomas Data Products, Inc. The Lightning One™ is the fastest processor board available on the SI 00 bus today. It contains not one processor, but three processors all working in parallel. It uses the Intel 8086 as the main processor. The math capability is augmented with the 8087 math processor and the I/O handling capabilities are augmented with the 8089 dual channel I/O processor. The board complies with all IEEE-696 specifications. If you have an 8 bit system presently, don't despair. The Lightning One is available with the 8088. The 8088 is fully software compatible with the 8086, but utilizes an 8 bit bus allowing use of your present 8 bit memories. When you are ready to upgrade to full 16 bit operation, you need only to unplug the 8088 and plug in an 8086 in its place. When using an 8088, the 8087 and 8089 may still be utilized. In addition to the Lightning One, Lomas Data Products has a full line of S100 bus support cards including: memory, disk controllers, and serial and parallel I/O. Prices for the Lightning One start at $395. Coming Soon: New Product Announcements: □ 128 K byte non-volatile static RAM □ M DRIVE for CP/M-86 and MS- DOS □ Dual CP/M-86 and CP/M 2.2 support D Winchester hard disk controller For 16 bit computing on the S100 bus, come to the leader . . , LOMAS DATA PRODUCTS, INC. 729 Farm Road, Marlboro, Massachusetts 01752 D Telephone: 617-481-2822 Circle 240 on inquiry card. JIT 1 10 • • • 86 Dos ro" BIT MAP UL RECORD NUMBER CORRESPONDING 1 TO BIT POSITION • • • Figure 1: Sample FORTHDOS disk bit map. A 1 in the bit map indicates that the cor- responding record number is in use. In this sample, records 2, 3, 4, and 6 are in use. BIT 8 9 • • 86 DOS BIT MAP FILE BIT 1 MAP FILE BIT 2 MAP EE. 1 1 1 1 1 • • • | ro 1 1 1 • • • | 1° 1 1 • • • | Figure 2: FORTHDOS bit map and file activity bit map, FILE1 is shown as using blocks 2, 3, and 6, while FILE2 is shown using blocks 4 and 9, The DOS bit map indicates which blocks are in use regardless of what file the blocks belong to; blocks 2, 3, 4, 6, and 9 are therefore indicated by the DOS bit map as being in use. BIT DOS BIT MAP (NEXT FREE RECORD IS 13 ) FILE 1 BIT MAP (CURRENT RECORD IS 10) RECORD 13 IS NOW FILE 2 BIT MAP (ADDS RECORD 13 FROM DOS) 13 • • • 86 [i • • • i 1 1 1 1 1 | | • • • | 1 1 • • • l 1 1 1 • • • | IN USE |0 • • • 1 1 1 |i|. . • 0| Figure 3: Using DNXT to find the next free record. As indicated in the DOS bit map, the next free record is 13. DNXT will scan the DOS bit map, find the free record, and change its corresponding hit to a 1. DOS BIT MAP AREA (11 BYTES) DOS COMMENT FIELD AREA (64 BYTES) FILE1 NAME (10 BYTES) FILE2 NAME (10 BYTES) FILE3 NAME (10 BYTES) FILE1 BIT MAP AREA (11 BYTES) FILE2 BIT MAP AREA (11 BYTES) FILE3 BIT MAP AREA (11 BYTES) DOS I/O BUFFER AREA ( 1024 BYTES ) Figure 4: FORTHDOS buffer area. FORTHDOS places all file bit maps and the DOS bit map in a common buffer area. This allows you to have as many files open at one time as you need. bytes long. Figure 2 shows our bit map structure so far — one disk activi- ty bit map (called DOS bit map) and multiple file activity bit maps. What of space contention, though? If each file bit map can map any record in the system, how does the DOS determine the file assignment of each record? The answer is very sim- ple. A FORTHDOS primitive ( DNXT ) scans the disk-activity bit map from high- to low-order bits un- til it finds a (unused record). That bit is changed to a 1, thereby marking the corresponding record as being in use. DNXT then marks the same bit in the CURRENT file (i.e., the file re- questing a free record) as also being in use. In figure 3, record 13 of both the DOS bit map and the FILEl bit map is initially 0. When FILE2 in figure 3 requests a free record, a call to DNXT causes the DOS bit map to be scanned. The next free record found by DNXT in this ex- ample would be record 13. This record's corresponding bit is then set to 1 in both the DOS and FILE2 bit maps (see figure 3). In this way, free records are allocated on a first-come, first-served basis by the DNXT primitive in the DOS. Two points are important here. First, note that DNXT does not care if the record number returned is the next consecutive record in the bit map, but it will return consecutive records if possible (i.e., if the record is not in use). This means that DNXT will produce contiguous records for a given file wherever possible. This shortens head-seek times across the disk. A primitive discussed below— KILL , which deallocates records — may be used by a clever DOS designer to ensure that a maximum amount of contiguous space is avail- able. (Many DOS packages have disk cleanup utilities which periodically remap bit maps so as to maximize the amount of contiguous record alloca- tion per file. For small systems, this is not needed.) A second point to note about this file bit map scheme is that it provides a simple method for inserting both sequential- and random-access file primitives into FORTHDOS. Sequential and Random Access In a sequential-access file, data records are accessed one after the other, without any gaps in the numeric sequence of records in the file. The ninth record cannot be ac- cessed after the tenth has been read ^without starting over at the first record and reading up to the ninth again. In a random-access file, on the other hand, data from any record number inay be accessed at any time. The ninth record may be accessed after the tenth or, for that matter, after any other record. Relative pointers are used in a random-access file. The record which the DOS has mapped in the bit map as record 341 may be relative record 10 to the user. That is, it may be the tenth record relative to the first record in the file. The DOS takes care of the correct translation of this relative record 10 into absolute record 341 on the disk. To minimize access time and max- 326 April 1982 © BYTE Publications Inc YOUR COMPUTER HEADQUARTERS SUPER SPECIAL! 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Accessories 67 West 47th Street, New York, N.Y. 10036 115 West 45th Street, New York, N.Y. 10036 MAIL ORDER ADDRESS: 36 E. 19th St. New York, N.Y. 10003 Circle 1 on inquiry card. BYTE April 1982 327 FORTH and Punctuation FORTH uses punctuation in some of its words, which makes representing them in text a difficult problem. For ex- ample, one FORTH word is ("), which could be taken to mean one of several character combinations. (For your in- formation, the word has three characters and is made from a left parenthesis followed by a double quote mark and a right parenthesis.) To decrease the chance of confusion while trying not to clutter text un- necessarily, we will sparingly use braces, { }, to isolate the character string within as a FORTH word or phrase. (For example, the above word would be written { (") } J Braces will be used only under the following situa- tions: • When the material being quoted is a phrase of FORTH words (e.g., { 26 LOAD }or{ 3 5 + } ) • with the FORTH words { . } (period), { , } (comma), { : } (colon), { ; } (semicolon) , { 1 } (question mark), { ! } (exclamation point), { ' } (single quote mark), and { ■" } (double quote mark) • with any word using the above punc- ' +uation marks (e.g. , { $. } or { ." } ). " All other FORTH words will be set 1 apart by a space on either side of the \ word; braces will always signal a FORTH word or phrase. The braces ! are not part of the word or phrase, and I FORTH words will never use braces ' within the body of a figure or \ listing. . . . GW FORTHDOS on Floppy Disk The author has agreed to make listings 1 and 2 available for a fee of $8 plus a floppy disk and a self-addressed return envelope: Due to the authors Canadian address and the expense of cashing foreign checks, the $8 must be paid with an international money order. Also, do not put postage on the return envelope; Canadian postage is included in the $8 fee. imize use of contiguous blocks of disk space for sequential and (particularly) random access, many DOS im- plementations utilize complex memory allocation techniques. FORTHDOS, however, uses multiple-file bit maps, a single DOS bit map, and a common I/O (in- put/output) buffer to avoid these complications without sacrificing speed or ease of use for small systems. Before describing how this is done for sequential- and random-access files, we must first look at file device con- trol blocks. File Device Control Blocks It is common DOS design practice to build OPEN and CLOSE primitives (e.g., OPEN and CLOSE commands in BASIC). The OPEN primitive creates a device control block (DCB) area in memory; this contains infor- mation on the file (its size, bit map, etc.) for use by the DOS until the CLOSE primitive writes the informa- tion back to the system area of the disk. In addition, OPEN creates a buffer area of RAM (random-access memory) within the DCB into which data is swapped back and forth from the file to other (user) areas of memory. This last point means that as the number of open files increases (as might be the case in a complex program), the amount of memory used by the file DCBs grows very rapidly. This is why many DOS systems limit the number of files which may be open at any given time. This manifests itself as the OUT OF FILE SPACE messages you get while executing a favorite program. Suppose we use a different method. Suppose that instead of using a DCB area for each file containing file statistics plus buffer space, we use a common small buffer area for all files and keep all file bit maps in memory at one time (they're only 11 bytes long). This allows you to have as many files open at one time as you wish without using up more than 11 bytes per open file (for 35-track disks). Figure 4 illustrates this. In other words, FORTHDOS uses two buffer areas. The first contains the file bit maps for all files in the sys- tem as well as their names and the DOS bit map. I've made this area 1024 bytes long, but it may be any length desired or even swapped in and out of memory as wished, with only current files kept in the buffer. The second buffer area is the one used for file I/O (which I have also made 1024 bytes long). Again, this may be of any length the user wishes. Since FORTH is a virtual system using a 1024-byte buffer (i.e., FORTH blocks can be seen as virtual memory that is swapped into memory when needed), I have set up the DOS to use this same buffer for all file I/O. Therefore, the total cost to the system for implementing FORTHDOS without a DCB struc- ture is only 1024 bytes of buffer space regardless of the number of open files per disk buffer. Armed with the conceptual tools of bit maps and DCB usage, let's ex- amine the way in which sequential- and random-access files are accessed through FORTHDOS. Bit Maps for Sequential and Random Access Notice in figure 5 that five files are in use (open) and that the record number that would be returned by the next use of DNXT is 53. Suppose we wish to add data to the next record available in the file, labeled ORANGE in figure 5. Assume that ORANGE is a sequential-access file. By using the DOS primitive WRITE , we would add our data from the buf- fer to ORANGE at record 53. WRITE would work as follows: 1. Call DNXT to calculate where the next free record is on disk (scan DOS bit map). Return with 53. 2. Set bit 53 in the DOS bit map to a 1 (i.e., in use). 3. Set bit 53 in ORANGE bit map to a 1. 4. Write any previous data from BUFF (the FORTHDOS I/O area in memory) if necessary. 5. Write the data from BUFF to record 53. Note the following points: the file bit map, ORANGE bit map, is filled according to the next available free record in the DOS bit map, not from 328 April 1982 © BYTE Publications Inc Iff it flies on aerospace software, Kearf ott...and you... may well help create it. As a company engaged in dozens of major projects that depend on software advances in flight, orbiting, command, communications or controls, we can offer you the opportunity to work in a DP complex that's as sophisticated as the ring laser gyroscope system we're developing for the Tomahawk-2 MRASM Cruise Missile. Or as advanced as our JTIDS communications terminal. 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RAM Jumper selectable on 8K boundaries . . . fully socketed . . . solder mask on both sides of board . . . phantom line . . . designed for 8080, 8085, and Z80 bus signals . . . works in Explorer, Sol, Horizon, as well as all other well-designed S 100 computers. k 10-DW MONEY-RACK TRIAL: Try a fully wired and tested board lor todays — then either keep i l. return It lor kit. or simply return ii in working condition. Continental U.S.A. Credil Card Buyers Outside Connecticut: ■ TO ORDER CALL TOLL FREE 800-243-7428 Z From Connecticul Or For Assistance: * (203) 354-9375 J Please send the items checked below: ; JAWS-IB kit: I □ 16K $149.95*: □ 32K $199.95* ■ □ 48K $249.95* ■ □ 64K $299.95* ; JAWS-IB Fully Assembled, Wired & Tested: □ 16K $179.95* S D 32K. . . $239.95* ■ D 48K $299.95* ■ a 64K $359,95* I □ EXPANSION KIT, 16K RAM Module, to expand* JAWS-IB in 16K blocks up to 64K. $59.95 'Ail prices plus $2 postage and insurance ($4.00 Canada/ ■ Connecticut residents add safes tax. * ■ Total enclosed: $ ■ O Personal Check D Money Order or Cashier's Check ■ P VISA □ Master Card (Bank No. ) : Acct. No. . Signature Print Name Address _ . Exp. Date . City _ State -Zip. 1^ NETRONICS R&D Ltd. ! Ifcll 333 Litchfield Road. N<>w Milford, CT (16776: LE NAME RECORDS US ED IN t ORANGE (3 RECORDS) 2. 10. 14, PEAR (5 RECORDS) I. 3. 4, 5, 6 APPLE (5 RECORDS ) 7, 8, 9, 11. 12 BANANA (25 RECORDS) 13, 17. 18 — ► 40. 41 TREE (14 RECORDS) 11, 15. 16. 19, 42— * 51. 52 A CAUL TO NEXT WOULD RETURN RECORD 53 (i.e., LAST RECORD USED WAS 52 IN FILE TREE). AFTER A SEQUENTIAL WRITE TO FILE ORANGE, ITS BIT MAP WOULD CONTAIN-. ORANGE ( 4 RECORDS ) 2. 10, 14, 53 Figure 5: Adding records to a sequential-access file. RELATIVE RECORDS 1 RECORD NUMBERS IN THE BIT MAP FOR FILE PEAR 72 €7 68 IE RECORD 84 IS CURRENT RECORD RECORD 34- - SEQUENTIAL READ- -+ RECORD 84 Figure 6: Random-access record retrieval. To sequentially read record 72, you would have to start at record 34 and go forward. A random read of record 72 would be done by calling RREAD to relative record 3, then doing a direct head move to that record. the ORANGE bit map. No other files are affected, regardless of how many are in use. Step 4 above is carried out only if the DOS has not previously taken care of writing the FORTH- DOS I/O buffer through prior pro- cessing. Reading such a sequential file is ex- tremely simple. If we look again at figure 5, we see that the ORANGE bit map shows the file ORANGE to con- sist of records 2, 10, and 14. The DOS primitive READ scans the ORANGE bit map from high- to low-order bits, moving the next record whose cor- responding bit is 1 to the I/O buffer BUFF. Since the ORANGE bit map con- tains Is in positions occupied by cor- responding record numbers used by the sequential file ORANGE and 0s elsewhere, it is unnecessary to mark the file on disk with an EOF (end-of- file) marker. It's easier and just as effi- cient to total the number of ones in ORANGE bit map and have the DOS read only that number of records from the file. Because only 11 bytes are involved, this can be done very rapidly. The only data that gets writ- ten to a file is user data without the need for EOR or other such markers. Random access is handled in a slight- ly different manner. Random Access In figure 6, the bit map for PEAR shows that records 34, 45, 72, 67, 68, and 84 are in use. If this were a se- quential-access file and we wanted to read record 72, it would be necessary to go to the beginning of the file and scan through until record 72 was found. By designating the file as random access, however, you can go im- mediately to record 72. Do so by entering a call to the FORTHDOS primitive RREAD (random-access read) with a relative pointer 3. This tells the DOS to scan PEAR bit map for the third 1 (i.e., the "in-use" bit) encountered. The record number cor- responding to this bit will then be read by the same primitive used to read a disk record for a sequential file. The only difference between ran- dom and sequential access in FORTHDOS is that the former scans a file bit map prior to an access to locate the absolute record number desired, while the latter must access the DNXT available record. Scanning is performed (in this ex- ample) over 11 bytes only — clearly much faster than forcing the DOS to sequentially read through as many as 86 blocks (an entire disk) before ar- riving at the desired record. This 330 April 1982 © BYTE Publications lnc $fy? . Jr % *%»*^ 4 Pluj> m L^vnf K hem TYPE ; C+! DUP C3 ROT + SWAP C! ; C-! DUP C3 ROT - SWAP C! ; 2C DUP 0= IF DROP 1 ELSE 1 SWAP DO 2* LOOP THEN ; DZONK BITMAP MAPSZ FILL ) DGT DUP 8 / DUP ROT ROT 8* - SWAP DUP ROT 21 ; DON DGT SWAP BITMAP Ca OR SWAP BITMAP C! ; DOFF DGT BM2 C! BITMAP C3 255 BM2 C3 - AND SWAP BITMAP DON? BM2 C! DUP DGT SWAP BITMAP C3 AND SWAP DROP 0* IF DROP ELSE BM2 C! THEN ; ( Type a number) ( Add tos to cvar) ( Subtract from c\'ar ) ( Raise 2 to tos power ( Used to determine a ( record's bit number) ( Clear the bitmap) ( Translate the block* ( in tos to bitpostion < Set a block to 'on') ( Set a block 'off ) ( If block* in tos is) ( used, bm2-block*) ( else bm2=0) CVARIABLE 1SB : DNXT EMI C BM2 Ca 0« I IF I BM1 C! BM2 ca <> DSKSZ DO I Dl ISB C3 >* AND LEAVE THEN LOOP BM1 C3 0* OR I L ■1 BM2 C! ' *** Thread Full ***' 1 s t block in a t h r e a d ) Find next free) C h k t h read i n t e q r 1 1 y ) Get block into bin 2) or i SSUffi a -1 f :i aq ) issue error msq ) ( * Access the directory through a virtual buffer) DREAD DADRS 3 DIRBLK 3 RBLK ; DWRITE DADRS 3 DIRBLK 3 WBLK ; DRD DADRS 3 BITMAP MAPSZ MOVE ; DWR BITMAP DADRS 3 MAPSZ MOVE ; MOUNT DZONK DREAD DRD ; DSAVE DWR DWRITE ; REMOVE DSAVE FLUSH CR " REMOVE DISKETTE" DINIT MOUNT DADRS 9 1024 FILL DZONK ; ( Read directory) ( Write directory) ( Read the bitmap) ( Save the bitmap) ( Mount di skette) ( Save directory) ( Remove diskette) ( Initialize dir) ( * Lookup fname: exit tos St bml =posi t i on in directory, or -1) : LOOKUP --1 BM1 C! DADRS 3 128 + N ! ( 1st 4 letters only) 13 DO ( are valid in fname) N 3 C3 <> IF N 3 C<& FNAME C3 ■ IF N a 1+ ca 1 FNAME Ca * IF N 3 2+ C;i) 2 FNAME C3 = IF N 3 3 + C3 3 FNAME C$ m IF I BM1 C! LEAVE THEN THEN THEN THEN THEN 64 N + ! LOOP BM1 C* ; ( * Add a new filename to the directory) : DPUTNM LOOKUP 255 <> IF " * FILE ALREADY EXISTS" ENTER ELSE DADRS 3 128 + N ! 13 DO N 3 Ci) m IF FNAME N 3 15 MOVE LEAVE N ELSE 64 N +! THEN LOOP N a <> IF " * FILE NAME SPACE IS FULL" ENTER THEN THEN ; ( * Prompt for and input a filename) : NAME FNAME 15 FILL SPACE " FILENAME:" SPACE FNAME 15 EXPECT ; ( * Obtain the f i 1 emap for the file named in : DGTMAP LOOKUP 255 < IF DADRS a 128 + BM1 Ca 64* + 20 + DUP N ! QMAP MAPSZ MOVE THEN ; ' fname' ) ( * Add a block to thread for 'fname' & leave * on tos, or O) : DADD DGTMAP DNXT BM2 C3 -1 <> IF BMi OS DUP DON DGT SWAP QMAP Ca OR SWAP QMAP Cf QMAP N a MAPSZ MOVE BMI C3 ELSE THEN ( find bitmap for) ( this file, get ) ( next in chain ) ( put it on tos ) Listing 1 continued on page 336 Computer Exchange ■ P.O. Box 1380, Jacksonville, OR 97530 ^P Ad# 930B APPLE 9 SUPPLY CENTER HARDWARE Apple n/n+ Direct Substitute for Apple Drives Micro-Sci A2 is a direct substitute for Apple II drives. Save $300 on a dual disk system. Micro-Sci 5" Drives for Apple II SAVE A2, 143K.5" Drive $395 18% A2 Controller and DOS $ 95 15% A70, 286K, 5" Drive $ 489 20% A40. 160K, 5" Drive $369 18% Controller Card for A70 and A40 $ 79 21% 320K RAM substitute for Disk System AXLON, RAMDISK320K Memory System $1145 20% Sorrento Valley 8" Disk Drive Controller $ 199 60% MONITORS: NEC 12" Color $359 24% 12" Green $169 22% 9" B&W $149 31% SANYO: 9" Green $159 31% 12" B&W $219 30% 12" Green $229 30% 13" Color $399 28% NEW 13" RGB Color $899 25% ZENITH 12" Green $119 20% DISKETTES, 5", box of 10: Maxell $ 39 33% Memo rex $ 25 45% 80 COLUMN VIDEO CARDS: Videx Videoterm $249 18% M&RSupRTerm $295 22% ALS: Smarterm $ 269 30% MISCELLANEOUS: Apple: Graphics Tablet (CLOSE OUT) $ 650 20% CCS: Serial Interface 7710A $139 22% Parallel Interface 7720A $ 99 20% Other CCS Cards In Stock, CALL CALL Hayes: Micromodem II $289 25% Smart modem $ 229 20% Keyboard Company: Joystick II $ 45 10% Game Paddle $ 25 17% Numeric Keypad $119 21% M&R: RF Modulator $ 25 27% SUPR FAN $ 39 25% j{ Microsoft: Z80 Softcard $ 279 33% 16L RAM Card $159 20% Mountain: CPS Multifunction Card $209 13% Clock /Calendar $239 15% Novation Applecat Modem $329 16% Orange Micro Grappler $129 21% DanPaymar LCA (NEW) $ 34 33% Saturn System 32K RAM Board $ 149 36% SSMAIO Serial /Para. Interface $159 20% ^ ALS, Smarterm 80 Col Card $269 30% * Z-Card (Z-80) $ 209 22% • Addram 16KCard $119 20% *Synergizer Package $549 27% NEC 16K Expansion Chips for Apple II $ 39 35% LETTER QUALITY PRINTERS: Qume Sprint 9 45RO $2195 23% Sprint 5 45RO $2395 20% Olympia (Typewriter/ Printer) ES-100. 18CPS w/full interface to Apple II $1695 22% PRINTERS: Epson, See special Epson section at right Intergral Data 445 Tiger w / Graph ics & 2K $695 23% 460 Tiger w/ Graphics $895 20% 560 Tiger w/ Graph ics $1095 22% Prism color printer w/Graphics $1695 16% Okidata Microiin82A $495 25% ORDERING INFORMATION: Minimum order $100. Money Orders, Cashier Checks welcomed . Visa and MC orders add 3% . Personal or company checks accepted (allow 20 days to clear). Add 3% for shipping, handling and insurance; UPS ground is standard. 6% total for UPS Blue or 10% total for APO or US Parcel Post. Include your telephone number. No COD's. Prices are subject to change without notice. Call to verify prices; ad errors do occur. Order desk hours are 8 to 6 PDT, 10 to 3 Saturdays. REFERENCES: We have been a computer dealer since 1978. Our bank reference is First Interstate Bank (503) 776-5620. We belong to the Chamber of Commerce, (503) 772-6293. SOFTWARE ondisk,or Apple II/II + Apple Software: Apple Fortran rffc $149 25% Apple Pilot Gf riO* 5119 27% Apple Plot w $ 49 30% Dow Jones News & Quotes $ 69 28% Dow Jones Portfolio Eval. $ 40 20% Microcourier $189 24% Many others CALL CALL Artsci Magic Window $ 75 25% if Ashton-Tate dBase 1 1 for Apple II $ 495 30% Aurora Systems Executive Secretary-WP $189 25% Broderbund Software Payroll $269 30% General Ledger $ 349 30% Apple Panic $ 21 30% Arcade Machine $ 32 30% Red Alert $ 21 30% Space Warrior $ 18 30% Many Others In Stock CALL CALL Budgeco, Raster Blaster $ 22 27% Calf. Pacific, Ultima $ 30 25% if Central Point Software: Copy II Plusver. 4 $ 35 10% Will copy most copy protected software for your backup in 45 seconds! NEW Continental Software Home Accountant $ 56 25% Home Money Minder $ 26 25% Data Most Snack Attack $ 22 25% Thief $ 22 25% Denver Software Financial Partner $185 25% Epson, MX 80 Graphics Dump $ 9 30% Hayden, Sargon II (chess) $ 29 22% High Technology Store Manager $189 25% Job Control System $ 469 40% Howard Software Tax Preparer 1982 ver. $ 1 15 25% Real Estate Analyzer $115 25% Creative Financing $115 25% Info Unlimited, Easywriter (PRO) $189 25% Innovative Apple Spellguard $219 26°/ if Insoft: Electric Duet NEW $ 25 20% ALD System II or III $110 10% TransFORTH II or III $110 10% Insoft Accountant $355 66% A full professional quality integrated GL, A/ft, A/P, Payroll package. Hotline support available. Send for free sample printouts. Requires Z8Q and 16K RAM card. ISA Spellguard $219 25% Micro Lab Data Factory, ver. 5.0 $ 249 20% Invoice Factory $129 35% Tax Manager $ 95 38% if Micro Pro CalcStar $189 36% WordStar $239 36% Super Sort $129 36% Mail Merger $ 79 36% Data Star $189 36% Spell Star $159 36% Microsoft A.L.D.S. $110 10% BASIC Compiler $299 25% Cobol 80 $ 559 25% Fortran 80 $149 25% Olympic Decathlon $ 24 24% TASC Compiler $159 22% Typing Tutor II $ 19 30% Muse Super Text II $113 25% Castle Wolfenstein $ 23 25% Robot War $ 29 25% ?/g||yf e 3101-10 = ====■ = Terminal $1195 SAVE 20% ta HEWLETT H/P85A $1,995 PACKARD SAVE $1,995 27% HP-85A Microcomputer with built-in printer and monitor HP-125New! Microcomputer 64K CPU /Terminal /Keyboard /Monitor $3095 18% HP-87 New! CALL CALL HP-41CV New! 2.2K Memory Calculator $ 245 25% HP-41C Calculator $ 185 26% Memory module for HP41C $ 25 25% Call for other HP equipment, software and accessories! Qz commodore VIC 20 Home Computer $249 16% CBM 8032 Computer $1059 20% CBM 4032 Computer $ 959 22% CBM 4040 Disk Drives (2) 343K $1019 21 % CMB 8050 Disk Drives (2) 1 Meg $1295 28% (alkS) COMPUTER SYSTEMS 8000-15 208K, 4 User, 2 Disks 8000-10 208K, 4 User, 10 Meg MTV-1 HD Mag Tape Backup Others in stock $3995 20% $6495 25% $2795 25% CALL CALL SUPRBRAIN =t!F=INTE3TEC while L DATA They Last SS SYSTEMS" Superbrain 64K QD $ 2895 28% EPSON PRINTERS MX70w/Graftrax MX80 MX80F/T MX100F/Tw/graphics $359 20% $ 449 31 % $ 555 25% $ 729 27% 70/ 80/ 100 Apple Interface and Cable $ 95 15% MXeOFriction feed adapter $ 59 22% MX80Graftrax $ 79 20% MX80/ 100 Atari Cable $ 29 22% MX80/100TRS 80 Cable $ 29 22% HEC Microcomputer 32K Computer PC8001 $ 750 25% 286K Total Dual Drive PC8031 $ 750 25% 32K addon and I/O Unit PC8012 $ 495 24% NEC PC Software CALL CALL 5 Meg Hard Disk $ 2995 Oswwuo 10 Meg Hard Disk $4345 IrOlVUS 20 Meg Hard Disk $5245 Omni-Net, Constellation, Mirror. In Stock CALL 21% 20% 20% XEROX • 820 System II Complete system includes monitor, keyboard, CPU and two disk drives SAVE With 5V4 inch dual drives $2495 18% With 8 inch dual drives $3095 19% On-Line Expediter II $ 75 25% Superscribe II $ 95 27% Lisa 2.5 $ 59 26% Pegasus II $ 22 25% Threshold $ 30 25% Cranston Manor $ 26 25% Mission Astroid $ 15 25% Mystery House $ 19 25% ('Osborne (Disk and Book) Some Common Basic Prog rams. 75 Business, Statistics and Math programs for the Apple $ 49 50% Peachtree Software Magic Wand $250 37% Gl, AR, AP, PR or Inv $189 38% , < ; ree gift with your order if you , mention - this ad. , Ad# 930B Personal Software/ V is i Corp VisiCalc3.3 $189 25% VisiDex $189 25% VisiFile $189 25% Desktop Plan II $189 25% VisiPlot $159 20% Desktop Plan III $209 30% VisiSchedule $239 20% VisiTrend and VisiPlot $239 20% VisiTerm $ 79 20% Zork $ 33 20% Softechlnt'l Stockf Me Stockseller Software Publishing: PFS II or III Report II or III Sorcim Supercalc Stoneware, DB Master (new version) $ 179 Sub Logic Flight Simulator $ 28 NO SALES TAX Oregon Order Desk (503) 772-3803 TOLL FREE NATIONAL ORDER DESK * Apple is a registered trademark of Apple Computer, Inc. (800)547-1289 Circle 103 on inquiry card. s Listing 1 continued: > ( * Make a new file St allocate directory space for it) : PROT? ( * Returns 1 if the file is protected, therewise 1 LOOKUP 255 <> IF RENM N 3 63 + Co) 170 = IF 1 ELSE THEN THEN i : 1STBK DBTMAP 85 DO I FON? ( set Isb) BM2 C5> DUP DUP <> IF ISB C! LEAVE ELSE DROP THEN LOOP ; © 1 MAKE ISB. C! NAME DPUTNM 1STBK ; ( Create/open a file) ( * Write buffer on tos to the file "fname") 3 : WRITE Nl ! PROT? 0= < don't write if rec> 1 ( * See if the file in fmap is using the black* in tos) : FON? IF DADD DUP > ( is protected ) IF Nl a) SWAP WBLK ELSE DROP a DUP DOT SWAP QMAP C® THEN THEN 3 AND SWAP DROP 0= if IF DROP BM2 C! ELSE BM2 C! THEN 5 9 ( * Routine to caluculate adress of a file from DOS RAM) ( t Random access of relative block** on tos to buffer at tos2) : RFIND : RENM DADRS S> 128 + BM1 C3> 64* + N ! ; DUP N ! BM1 C! Nl ! DSKSZ ( * Kill the file named in fname) DO I FON? BM2 C*> > ( loop to find ) : KILL IF 1 BM1 C-! BM1 Co) > NOT ( relative rec#) NAME LOOKUP 255 <> IF I N ! LEAVE IF DOT MAP DSKSZ THEN DO I FON? BM2 C® <> THEN IF BM2 Ca DOFF LOOP THEN 5 LOOP RENM N 3 64 FILL THEN ; ( * Random read block# at tos to buff at tos2, exit=l if okay) : RREAD RFIND BM1 CS> > IF ELSE Nl 5) N $ RBLK 1 ( * Read the next block in "fname' into the buffer at tos) THEN | : READ Nl ! DBTMAP BM1 CS> -1 <> IF ( # Random write block** at tos to buff at tos2„ exit = l if okay) BEGIN NBLK 9 DSKSZ > ( * Note that user may only write to a block already allocated) IF NBLK ! i RWRITE RFIND BM1 C5> > THEN IF 1 NBLK + ! NBLK S FON? BM2 Co) <> ELSE N S> PROT? 1 ■ IF Nl 3 BM2 Co) RBLK 1 IF DROP ELSE ELSE N ! Nl S> N 3 WBLK 1 THEN THEN END THEN ; THEN 5 ( # These words alter the write protect status of a file) : PROTECT NAME LOOKUP 255 O ( * Print the # of blocks used by the file in fname) IF RENM 170 N 5) 63 + C! : FSIZE THEN DGTMAP BM1 Co) -1 <> . IF BM1 C! DSKSZ DO I FON? BM2 CS> > : UNPROTECT IF 1 BM1 O! NAME LOOKUP 255 O THEN IF RENM N 5> 63 + C! LOOP THEN BM1 CS> SPACE T# SPACE " Blocks" . THEN * THE FORTH SOURCE Specializing in the FORTH Language TM FORTH MANUALS, GUIDES, & DOCUMENTS PRICE □ "Starting FORTH" by Brodie. Prentice Hall. Best user's manual available, (soft cover) $16.00 □ "Starting FORTH" (hard cover) 20.00 □ "Systems Guide to fig-FORTH" by Ting. Excellent guide to inner mechanisms. 25.00 □ "Using FORTH" by FORTH, Inc. Guide to concepts 25.00 □ "A FORTH Primer" by Stevens. In-depth self-study manual 25.00 □ "Caltech FORTH Manual" by Ewing. Overview and Structure. 12.00 D "Threaded Interpretive Languages" by Loeliger. Byte Books. FORTH adapted for Z80 20.00 D "Invitation to FORTH" by Katzan. Petrocelli Books. Limited introduction. 20.00 D "PDP-11 FORTH User's Guide" by James. 20.00 □ "AIM FORTH User's Manual" by Rockwell- International 12.00 □ "APPLE FORTH-79 User's Manual" by MicroMotion 20.00 G "TRS-80 MMSFORTH User's Manual" by Miller Microcomputer Services. 18.50 □ "FORTH-79". Latest FORTH Standard. 15.00 □ "FORTH-79 Standard Conversion" by Smith. Implementation aids. 10.00 D "METAFORTH" by Cassady. Cross compiler with 8080 code. 30.00 D "Tiny PASCAL in fig-FORTH" by Zimmer. 10.00 Proceedings of Technical Conferences G "1980 FORML" (FORTH Modification Laboratory) 25.00 G "1981 FORML" Two Volume Set 40.00 D Volume I, Language Structure 25.00 □ Volume II, Systems and Applications. 25.00 □ "1981 Rochester University" 25.00 FORTH HARDWARE G AIM65 Microcomp by Rockwell. 4K RAM, FORTH IC's and manuals {plus $20,00 handling and shipping) $530.00 INSTALLATION DOCUMENTS D Installation Manual for fig-FORTH, contains FORTH model, glossery, memory map, and instructions Source Listings of fig-FORTH, for specific CPU's and computers. The above installation manual is required for implementation. Each □ 1802 G 6502 □ 6800 G AiphaMicro □ 8080 □ 8086/88 D 9900 Q APPLE II® □ PACE 6809 G NOVA G PDP-11/LSI/11 FORTH DISKS WITH DOCUMENTATION fig-FORTH Model and Source Listing, with printed Installation Manual and Source Listing. □ APPLE II® 5 1 /, □ 8080/Z80® 8 G 8086/8088 8 G H89/Z89 5V. G APPLE ll/M + ® by MicroMotion. Version 2. FORTH-79 Standard, editor, assembler, 200 pg manual, 5'i G Option 1 - floating point and HiRes Turtle Graphics G Option 2 - DBMS, DOS/FORTH, modem utilities Q Combo Package - All of the above G APPLE II by Kuntze. fig-FORTH editor, assembler, source listing and screens, 5 1 /, D ATARI® by Pink* Noise Studio. fig-FORTH, editor, assembler, missile graphics, sound and handle drivers, 5'/ 4 G CROMEMCO® by Inner Access fig-FORTH editor, assembler, 5'/« or 8 G PET® by FSS. fig-FORTH editor and assembler, 5'/ 4 G PET® with floating point, strings, disk I/O G TRS-80/1® by Nautilus Systems. fig-FORTH, editor and assembler, 5 1 /, G TRS-80/1 or III by Miller Microcomputer Services. MMSFORTH, FORTH-79 subset, editor, assembler, dbl-precision, arrays, utilities & applications. 210 pg manual, 5V, G HP-85 by Lange. fig-FORTH, editor and assembler, 5' □ H89/Z89 by Haydon. fig-FORTH, CP/M® source, editor.assembler, & tutorial on disk, 5V, G CP/M® , Z80 by MicroMotion. Version 2.x, FORTH-79 Standard, editor, assembler, 200 pg manual 5'/ 4 G Enhancement Package - floating point, DBMS & modem utilities. D Combo Package - all of the above G 6800 by Talbot Microsystems. fig-FORTH, editor, assembler, disk I/O, FLEX® 5\ or 8 G 6809 by Talbot Microsystems. fig-FORTH, editor, assembler, disk I/O, FLEX® 5% or 8 G 6809 Enhanced 2nd screen editor, maeroassembler,tutorial, tools and utilities, FLEX G Z80® by Laboratory Microsystems. Editor and assembler, CP/M, 8 G Z80 with floating point D Z80 with AMD 9511 support $15 00 D Z80 by Inner Access. Editor, assembler and manual, CP/M, 8 G 8080 by Inner Access. Editor, assembler, and manual 15.00 CP/M, 8 Q 8086/88 by Laboratory Microsystems. Editor, assembler, CP/M -86® , 8 □ 8086/88 with floating point, CP/M-86 G 8086/88 with AMD 9511 support CP/M-86 PRICE $65.00 $100.00 50.00 50.00 $180.00 $90.00 $90.00 $100.00 $90.00 $150.00 $90.00 $130.00 % $90.00 $175.00 $100.00 $70.00 $150.00 $100.00 $100.00 $250.00 $50.00 $150.00 $150.00 $100.00 $100.00 $100.00 $200.00 $200.00 Cross Compilers by Nautilus (NS), Talbot Microsystems (TM), Laboratory Microsystems (LM) and Inner Access (IA). Allows extending, modifying and compiling for speed and memory savings, can also produce ROMable code. c cp/m (ns) $200 G H89/Z89(NS)$200 :. : Z80 (LM) $200 i: 6809 (TM) $250 GCP/M (I A) $450 □ TRS80/I (NS) $200 G Northstar (NS) $200 D 8086 (LM) $300 G Cromemco (IA) $450 ORDERS ONLY (415) 961-4103 DEALER & AUTHOR INQUIRIES INVITED Ordering Information: Check, Money Order (payable to MOUNTAIN VIEW PRESS), VISA or MasterCard accepted. No COD's or unpaid PO's. California residents add 6V2 % sales tax. Shipping costs in US included in price. Foreign orders, pay in US funds on US bank, include for handling and shipping by Air: $5.00 for each item under $25.00, $10.00 for each item between $25.00 and $99.00 and $20.00 for each item over $100.00. Minimum order $ $10.00. All prices and products subject to change or withdrawal without notice. Single system and/or single user license agreement required on some products. MOUNTAIN VIEW PRESS, INC. PO BOX 4656 MOUNTAIN VIEW, CA 94040 (415)961-4103 Circle 286 on inquiry card. BYTE April 1982 337 Listing 1 continued: ® i I O ( * Prints the number of free blocks on the current disk) : FREE BMI C! DSKSZ DO I DON? BM2 C3 > IF 1 BMI C+! THEN LOOP CR DSKSZ BMI C5> - Ttt SPACE " Free disk blocks" SPACE " out of" SPACE DSKSZ Ttt CR ; ( * Loads - compiles - a given filename for execution) : RON NAME LOOKUP 255 <> IF CR DSKSZ DO I FON? BM2 CS> <> IF I LOAD THEN LOOP THEN CR ; ( * List the file named in 'fname') : SHOW NAME LOOKUP 255 < > IF FSIZE BMI CS> DUP 0= IF DROP ELSE DO VIDEO READ LOOP THEN THEN ; ( * List the file names from the directory) : FILES DADRS S> 128 + Nl ! CLS 23 PTC " Disk Directory" 1 23 PTC 14 DO 131 ECHO LOOP CR CR DADRS 3 64 + 64 TYPE BM3 C! CR 13 DO Nl 9 E9 <> IF Nl 3 FNAME 15 MOVE PROT? i> IF ' I" ELSE SPACE THEN FNAME 10 TYPE FSIZE BM3 C3 0= IF 1 BM3 C! 220 ECHO ELSE BM3 C! CR THEN THEN 64 Nl +! LOOP CR ' S PAD - Ttt SPACE " Free bytes of" SPACE " memory" FREE " <* - write protected file)" CR ; From here on uti the utilities ta unless the user in the name of t then loads the u appropriate disk from core when d Note that "assiq in thi s 1 i sti ng computer system, which &re not gi You may easily FORTHDOS by foil lities only are listed. Note that ke space, so they Are not core resident calls them in. This is done by typing he utility or command desired. FORTHDOS tility from the system area of the executes the utility, erases the utility one, and returns control to the user. ', 'time', and 'timeset' are not included since their functi on is peculiar to my There are f however, some utilities listed ven in the text. add your own utilities or programs to owing the scheme used to call utilities. ( * Add any utilities you wish to FORTHDOS starting here.) GAUX AUXDOS 9 + LOAD ; (This word loads the utility LOCK GAUX ; SETDIR 1 GAUX ; RENAME 2 GAUX ; COPYALL 3 GAUX ; FCOPY 4 GAUX ; BLOCKS? 5 GAUX ; PS HOW 6 GAUX BCOPY 7 GAUX ( * Lockout any blocks the user wishes to be write protected) : *L0CK BEGIN " Blocktt to be locked out (-1 if none):" ttIN DUP -1 ■ IF DROP 1 ELSE DON THEN CR END ♦LOCK FORGET *L0CK ( I Set up a new directory via prompts to the user) : * SETDIR CLS 23 PTC " NEW DIRECTORY" CR CR " Build a new directory (& destroy all files)" Y/N NOT IF DINIT CR " Write protect below block*" SPACE ttIN DO I DON LOOP CR LOCK FNAME 64 FILL DTRBLK 8 DON DWR DADRS 9 64 + N ! " Diskette description: " FNAME 64 EXPECT FNAME N :H> 64 MOVE FNAME 64 FILL DSAVE THEN CR ; ♦SETDIR FORGET ♦SETDIR ( ♦ Give din old file a new name via the console of a program) : *RENAME SPACE BMI C5> -2 <> IF " OLD" NAME LOOKUP -1 * IF SPACE " * NOT FOUND" ENTER ELSE RENM SPACE " NEW" NAME FNAME N 3 15 MOVE CR THEN ELSE LOOKUP 255 <> IF 9 FNAME SWAP 15 MOVE THEN THEN ; ♦RENAME FORGET *RENAME ( * Copy tos blocks of the file in : *C0PYALL DO to ' f name' ) Listing 1 continued on page 340 Jli Letterhead? Multicopy cut forms? Plain bond paper? Ditto masters? Try the Easy Feed ■^ single sheet paper load option with ■^ MPI's 88G and 99G printers. Just feed the paper in the front and watch it come out the top. No round plat- rens to bend around or complicated paper paths to worry about. All this in addition to the standard adjustable width tractor drive, dot graphics, 1,000 character buffer, dual parallel/serial interface, dual fonts and much more. 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Ltd 690-4000 Telex; AA30906 • Canada Norango (416) 498-5332 Telex: 06966710 » Mexico, Central and louth America Siscom-trol (905) 689-02-09 g Listing 1 continued: > 3. I O FNAME IMF 5 MOVE ONAME FNAME 5 MOVE VIDEO READ TMP FNAME 5 MOVE VIDEO WRITE LOOP CLS O ONAME 5 TYPE SPACE " copied to" SPACE FNAME 5 TYPE CR ♦COPYALL FORGET ♦COPYALL ( ♦ Copy one -file to another) : ♦FCOPY SPACE " Copy from" NAME LOOKUP -1 = IF " * NO SUCH FILE" ENTER ELSE FSIZE BM1 CS Nl ! FNAME ONAME 5 MOVE SPACE " To" NAME SPACE LOOKUP 255 = IF CR " (New File)" DPUTNM Nl S> COPYALL ELSE CR " (Copy over old ■file)" Y/N NOT IF Nl ffl COPYALL THEN THEN THEN ; ♦FCOPY FORGET *FCOPY ( ♦ Print the blocks used by a given file name) : * BLOCKS? NAME LOOKUP 255 <> IF CR " Blocks in use:" SPACE DSKSZ DO I FON? BM2 Co) O <> IF I Ti SPACE THEN LOOP THEN CR ; ♦BLOCKS? FORGET *BLOCKS? < FORTHDOS Printer routines - header, pagesize, number, etc.) B PIT | VARIABLE PAGESZ VARIABLE SPC ( " (C) P. Reece 1981" VARIABLE FG : GETtt CR " Li " Spacing" # " Title:" SP : HEAD KNT 5) 30 ECHO T : KNTDO SPC 9 : GO CLS PCRT IF 16 DO I I THEN 1 START : ♦FSHOW NAME 15 ECHO 176 VARIABLE START VARIABLE KNT 64 CARRAY TITLE nes/page" #IN PAGESZ ! CR BL TITLE 64 FILL IN SPC ! CR " Starting Page #" #IN PG ! CR ACE TITLE 63 EXPECT CR ; m IF " Page" PG ? SPACE ITLE 64 TYPE 29 ECHO CR CR 1 PG + < THEN ; 1 DO 1 KNT ■*•« CR LOOP ; KNT ! HEAD BEGIN START 9 FON? BM2 C9 O <> BM2 C3 LINE DROP 64 TYPE KNTDO KNT 9 PAGESZ a) >= F CR CR CR 7 ECHO KEY DROP KNT ! HEAD THEN LOOF START 3 DSKSZ > IF 1 ELSE O THEN END ; LOOKUP 255 <> IF GO CRT CRT CR " Finished" CURSOR ! THEN CR ; *PSHOW FORGET PIT " Single Drive BLOCK copy - Peter Reece (c) 1980" : TASK ; VARIABLE K r B PAD - 1024 / 1024 * 1024 - K ! VARIABLE FROM 9 CONSTANT MAXSZ MAXSZ CARRAY TXT VARIABLE TO VARIABLE EN RD CLS 10 O PTC 23 ECHO " Insert SOURCE Disk" ENTER WHILE N «> MAXSZ < END 3 FROM 3 >« AND PERFORM N 3 TXT FROM 9 RBLK 1024 N +! 12 O PTC FROM ? " ->" 1 FROM +! FEND J WT CLS 10 PTC 23 ECHO " Insert DESTINATION Disk" ENTER N ! WHILE N 2 MAXSZ < K 3 TO 9 >= AND PERFORM N 3 TXT TO 9 WBLK 1024 N +! 12 PTC " ->" TO ? 1 TO +! FEND ; CYCLE WHILE K 9 TO 9 >» PERFORM RD WT O N ! PEND ; *BCQPY CLS 5 PTC " START BLOCK#" #IN FROM ! CR " END BLOCK# #IN END ! CR " DESTINATION BLOCKtt" #IN TO ! END $ FROM <& - TO $ + K ! CYCLE CLS " Bcopy Done" CR ; *BCOPY FORGET TASK ( * Same drive FILE copy - minimal RAM, so lots of swaps) : *XCOPY DSAVE SPACE " Copy from" NAME LOOKUP -1 = ( source? IF " * NO SUCH FILE" ENTER ( not there ELSE DSAVE FSIZE BM1 C3 Nl ! ( get its sz FNAME ONAME 5 MOVE SPACE " To" NAME Nl 8 DO C 1 at a time CR " Insert SOURCE Disk" ENTER MOUNT FNAME TMP 5 MOVE ONAME FNAME 5 MOVE VIDEO READ TMP FNAME 5 MOVE CR " Insert DESTINATION disk" ENTER MOUNT 1 0* IF LOOKUP 255 - IF DPUTNM THEN THEN VIDEO WRITE DSAV LOOP CLS " Xcopy Completed" CR ( i f a new file ( build it in < then save it THEN THEN * XCOPY FORGET * XCOPY (" (C) Peter Reece 1981 ' HB Improve Your Memory With a Free Scotch Brand Data Cartridge. Buy One, Get One Free! We want you to try our Scotch Brand DC100A Certified Data Cartridge. We're so sure you'll like it that we'll send you a free one when you order one data cartridge at the regular price of just $18.00. No strings attached. Two of these superior data cartridges for the price of one. Scotch Brand _ _ imjJ __ Data Cartridges are compatible with all Hewlett- Packard mini- cartridge computers, including the popuU They also fit the Savin Veritext® 950 word processor, the TI-770 terminal, Tektronix models 4041 and DAS-9100 and many others. We invented the certified data cartridge and our special back treatment process makes our tape extra durable and longer lasting. Enlarged end-of-tape sensor holes are provided for improved end-sensing reliability. Scotch Data Cartridges are quiet, too, and come with a one year warranty. Order Now! Get a Free Protective Case. Order now and we'll send you a rugged, heavy- duty protective shipping and storage case that holds two data cartridges. But don't wait, quantities are limited. (Offer limited to one free data cartridge per customer.) HOW TO ORDER: Send check or money order for $18.00 (plus applicable state sales tax) or charge to your Master Card or VISA account. Fill out the coupon and send to the address shown. Please allow 6-8 weeks for delivery. Offer expires September 30, 1982. r i i i i SHIP TO: Name Company. Address_ City Phone Signature, Title. State. Zip. . Computer Type_ ($18 plus state sales tax) □ Total enclosed $ Make check or money order payable to 3M. □ Charge to □ Visa or □ Master Card. Card No SEND TO: 3M, Dept. PM-E3, DATA RECORDING PRODUCTS DMSION/3M, P.O. Box 33133, St. Paul, MN 55133 Expires. i i i i j 3M hears you... 3M The FORTHDOS Demonstration Program The FORTHDOS demonstration program (see listing 2) enables you to easily familiarize yourself with all of the primitives (and two utilities— by way of example) described in the arti- cle on FORTHDOS. In addition; it il- lustrates how the basic primitives can be configured to use a shorter record length (here, 64 bytes per record) in a very simple manner. The demonstra- tion program is an application pro- gram that illustrates some of the ways to issue calls to FORTHDOS and then deal with the results of those calls. The program has been designed for use on the TRS-80 Model I with 4SK bytes of memory running the MMSFORTH system version 1.8, (If you have ver- sion 2.0, this program may require modification.) Applications Programs Before using the demonstration pro- gram, it is important that you realize the role of FORTHDOS in program- ming. FORTHDOS is a list of primitives that perform various func- tions in response to calls from a user- written program. Most primitives return status flags for use by the ap- plications software. The software then uses those flags to determine subse- quent action following the FORTH- DOS call The demonstration program given here is an example of a very simple means of issuing calls to FORTHDOS and viewing the results. It is a straightforward applications program. The program has been kept simple for ease in following the logic of ac- cessing FORTHDOS. It should be noted, however, that the resulting limitations of the program are not limitations of FORTHDOS. For example, upon selecting a sequential-write option from the com- mand menu, the demonstration pro- gram makes a call to FORTHDOS to write the appropriate record to the file currently opened (i.e., in FNAME). FORTHDOS does so, returning status flags regarding the success of the write operation. It is the demonstration pro- gram, not FORTHDOS, that puts the entire block just accessed on the screen, ignoring end-of-file marks, for you to see more clearly what is going on. The DOS acts normally; it is the demonstration program that performs the apparently strange task (as a learn- ing aid) of displaying an entire block of data — even if the block contains data from another file. The demonstration program is designed as a simple and easy-to- follow application program that calls FORTHDOS primitives. As such, its simplicity may be misleading. Look carefully at the apparent mistakes you discover in the program. They exist for a reason — namely, to illustrate various approaches to calling the primitives. Remember, FORTH-DOS primitives perform transparent actions and return flags (in most cases) to indicate the results of those actions. What your ap- plications program does with the results of FORTHDOS calls or how it uses them (as illustrated by the demonstration program) is strictly up to you. How to Use the Program To use this program, first make a backup copy of your MMSFORTH disk. Then type in and save this pro- gram (listing 2) on that disk. To use the disk, place it in drive and boot the system. Load the demonstration pro- gram by typing { 20 12 LOAD }, then type FORTHDOS and press ENTER. The demonstration program command menu will be displayed on the screen (see figure 12). Begin checkout by selecting item 1 on the command menu. This option will cause FORTHDOS to read the directory. When this has been done, select item 14 from the menu. This will list the files available for use by the program. Records vs. Blocks A word is in order regarding the pro- gram's ability to access and deal with 64-character records. FORTHDOS is quite versatile. It is really a series of subroutines callable by a user-written drive program (e.g., the demonstration program). As such, the record length is external to the primitive subroutines and may be controlled totally by the) READ and WRITE calls from the user's program. For example, the routines DSKIO and WRITEl in the program use a 64-character record and count 16 of these records per 1024-byte block (via the variable RREC). This record length could just as easily have been 16 bytes, with RREC counting 64 records before a new block is called into memory by FORTHDOS. The examples in the program should enable the careful reader of both the article and code to configure his or her system for any record size or even variable record sizes. The program allows you to familiarize yourself with the innards of FORTHDOS. It also allows you to make mistakes and see the results of incorrect calls (potential- ly by your own software) to the FORTHDOS primitives. For instance, if in reading to the end of a sequential file you forget to reset the file (item 18 in the menu), you will not be able to read an earlier record (unless you first CLOSE or RESET it). (Note that LIST, item 7, automatically resets the file prior to a list, then returns it to its original state once the listing is completed.) Experimentation will be the best teacher here. Finally, unlike the wealth of com- ments and structured code of FORTH- DOS as presented in the body of the artcile, this program (listing 2) has a very compact version of FORTHDOS. This is meant to be a run-time package for direct implementation on your system. To incorporate it directly into your own software, eliminate the menu and associated routines by deleting the following words recompiling; MENU1 MENU FORTHDOS TITL This will leave you with a core of FORTHDOS primitives compactly squeezed into a minimum number of screens and ready to use. 342 April 1982 © BYTE Publications Inc Making small printers for people who think big. OKIGRAPH Dot Addressable Graphics Prints Circles Around The Competition Or squares. Or charts. Or graphs. Or illustrations. Or any graphic data your computer tells it to print. All with superb clarity and resolution. OKIGRAPH™ is standard equipment on the Microline 84 and the Model 2350. It's an easily added option to the Microline 82A and 83A. So don't settle for the plain old text you get with other printers. Be creative. With Okigraph. Interested? Contact us at 111 Gaither Drive, Mount Laurel, N.J. 08054, or call (800) 257-7768 for the name of your local authorized Okidata distributor. Okidata is a subsidiary of Oki Electric Industry Company Ltd. • OKIGRAPH™ I includes two plug-in PROMs and an instruction manual on Assembly language programming. • OKIGRAPH™ II includes a floppy disk for addi- tional graphics printing features and an instruc- tion manual. Microline 82A Microline 83 A Microline 84 Circle 302 on inquiry card. BYTE April 1982 343 i @ 3 Listing 2: FORTHDOS demonstration program. Once the program in listing 2a has been loaded, the demonstration program is started by executing the word FORTHDOS. This listing contains a slightly simplified version of the FORTHDOS program as given in listing 1. The differences are as follows: some constants and variables are precalculated to assume a 1-drive, 48K-byte system; the disk-resident utilities at the end of listing 1 are not included in listing 2; some definitions in listing 2 are slightly different from their counter- parts in listing 1, although they are functionally the same; other definitions have been changed to reflect a 64-byte record size (see "The FORTHDOS Demonstration Program" text box). Also, in this listing, the apostrophe in the MMSFORTH word { 2' } (block 22) is actually an up-arrow symbol. Listing 2b (block 32) executes a 1-drive block copy routine. (2a) BLOCK s 20 (" FORTHDOS DEMO 1 - me) ory buf > t recrd) t block) vars) vars) k in fl) of buf) file) fntn) demo) demo) 1 demo) (" FORTHDOS DEMO 2 - (C) Peter Reece 1981" ( * Put/clear a message on the bottom of the crt.) : S* DO 140 ECHO LOOP ; : Z1AR BL AR1 64 FILL ; : MSG 14 PTC 63 S* 15 PTC 30 ECHO SPACE ; : CMSG ENTER 14 PTC 30 ECHO 15 PTC 30 ECHO ; ( * Here lie some general purpose utilities.) - t# <# # ttS #> TYPE ; < Type a formatted #) : DELAY 5000 DO LOOP ; < Delay a bit) : NAME BL FNAME 15 FILL MSG ( Get file name) " FILENAME:" SPACE FNAME 15 EXPECT CMSG ; : C+! DUP 3 ROT + SWAP C! ; i Byte add) : C-! DUP C3 ROT - SWAP C! f < Byte subtract) : -! DUP S) ROT - SWAP ! ; < Word subtract) I TITLE CLS 12 PTC " FORTHDOS DEMONSTRATION DISKETTE" 1 12 PTC 31 S* 50 PTC " (C) P. Reece" ; BLOCK : 22 C" FORTHDOS DEMO 3 - CO Peter Reece 1981" ( * Dos primitives. ) : 2* DUP 0= IF DROP 1 ELSE 1 SWAP DO 2* LOOP THEN ; : DGT DUP 8 / DUP ROT ROT 8* - SWAP DUP ROT 2* ; : DON DGT SWAP BITMAP CS OR SWAP BITMAP C! ; : DOFF DGT BM2 C! BITMAP Co) 255 BM2 C3 - AND SWAP BITMAP C! ; : DON? BM2 C! DUP DGT SWAP BITMAP CS AND SWAP DROP 0= IF DROP ELSE BM2 C! THEN ; : DNXT BM1 C ! 85 1 DO I DON? BM2 CS 0= I 1SB CS >* AND IF I <> BM1 CS 0« OR IF -I BM2 C! DREAD DADRS $ RBLK ; DRD DADRS S BITMAP 15 MOVE | DWR BITMAP DADRS 3 15 MOVE ; MOUNT DZONK DREAD DRD ; REMOVE D3AVE FLUSH MSG " Remove disk now DIN IT MOUNT DADRS 3 1024 FILL DZONK ; BM1 C! LEAVE THEN LOOP BM2 CS MSG " THREAD FULL" CMSG THEN ; : DWRITE DADRS $ WBLK g : DZONK BITMAP IS FILL ; : DSAVE DWR DWRITE ; CMSG ; BLOCK 23 (" FORTHDOS DEMD 4 - (C) Peter Reece 1981" : L00K1 -1 BM1 CI N S CS FNAME CS <> IF -1 BM1 C! ELSE 15 DO I FNAME CS N 9 I + CS - IF I BM1 C! ELSE -1 BM1 C! LEAVE THEN LOOP THEN BM1 CS i : LOOKUP DADRS S 128 * N ! 14 DO L00K1 255 ■ IF 64 N +•! ELSE I BM1 C! LEAVE THEN LOOP BM1 CS) ; s DPUTNM LOOKUP 255 = IF DADRS 3 128 + N ! 14 DO N 3 C3 6- IF FNAME N 3 15 MOVE LEAVE N ! ELSE 64 N + ! THEN LOOP N S <> IF MSG " FILE SPACE FULL" CMSG 22 M ! THEN THEN ; : DGTMAP LOOKUP 255 <> IF DADRS S 128 + BM1 CS) 64* + 20 + DUP N ! QMAP 3.5 MOVE THEN ; : DADD DGTMAP DNXT BM2 C® -1 <> IF BM1 CS DUP DON DGT SWAP QMAP CS OR SWAP QMAP C! QMAP N 3 15 MOVE BM1 CS ELSE THEN ; : NREC RDBK 9 1SB CS - 16* RREC CS +■ SPACE " <" Ttt " )" ENTER J BLOCK : 24 <" FORTHDOS DEMO 5 - (C> Peter Reece 1981" ( * Dos primitives.) 3 CLOSE BL FNAME 15 FILL $ : RENM DADRS 8 128 + BM1 C3 64* + N ! ; : FON? DUP 86 < IF DUP DGT SWAP QMAP CS) AND SWAP DROP 0= IF DROP BM2 C! ELSE BM2 C! THEN ELSE DROP BM2 C! THEN ; : KILL LOOKUP 255 <> IF DGTMAP 85. DO I FON? BM2 CS> <> IF BM2 C» DOFF THEN LOOP RENM N 3 64 FILL CLOSE THEN ; : DTNM SPACE FNAME 15 TYPE ; ( Print filenm)' : FSZ1 DGTMAP BM1 CS) -1 <> IF BM1 C! 85 DO I FON? BM2 CS) > IF 1 BM1 C+! I Fl C! THEN LOOP ELSE 1 THEN ; : FSIZE FSZ1 0= IF BM1 CS MSG T# " Blocks" CMSG THEN ; : FREE BM1 C ! 85 DO I DON? BM2 CS > IF 1 BM1 C-H THEN LOOP 85 BM1 CD ~ 16* MSG T# SPACE H free records left" CMSG ; : BLOCKS? CLS 2 20 PTC " LIST OF BLOCKS IN" DTNM CR 63 S* CR DGTMAP BM1 CS) 255 <> IF 85 DO I FON? BM2 CS) > IF I . THEN LOOP THEN CR CR ENTER ; BLOCK : 25 (" FORTHDOS DEMO 6 - (C) Peter Reece 1981" ( * These routines read a 64-byte record from disk.) : 1STBK DGTMAP 85 DO I FON? BM2 CS) < Get 1st block in fl) DUP <> IF DUP RDBK ! 1SB C! LEAVE ELSE DROP THEN LOOP ; : MEOF MSG " END OF FILE REACHED" CMSG ; : GRDBK RDBK 8 M ! DGTMAP BM1 CS -1 <> IF BEGIN M S) FON? BM2 CS <> IF BM2 CS RDBK ! 1 ELSE 1 M +! THEN M S> 85 > IF -1 M ! DROP 1 THEN END THEN ; : DSKIO RDBK § 1+ 85 > IF MSG " DISK FULL" CMSG ELSE RREC CS RDBK S LINE DROP AR1 64 MOVE 1 RREC CH-! AR1 60 TYPE RREC CS 15 > IF RREC C! 1 RDBK *1 GRDBK THEN EOF CS 1 = IF MEOF THEN M S -1 = IF 1 EOF C! MEOF THEN AR1 CS 127 ■ IF 1 EOF C! MEOF THEN THEN ; : ZPNTRS RREC CI 1STBK ; 5 READ MSG 14 PTC DTNM 15 PTC DSKIO 14 40 PTC NREC : Listing 2 continued on page 346 Introducing . . . THE TEC-86 SERIES OF 16 BIT MICROCOMPUTER SYSTEMS TEC-86 -COMPLETE 16 BIT 8086 MICROCOMPUTER SYSTEM— $4390 FEATURES • Two 8 Inch DD Floppy Disk Drives (1.2 MB Total) • ROM Boot for MP/M-86m • 64K Bytes of Memory • Vectored Interrupts • 16 Bit 8086 CPU • Heavy Duty Power Supply • IEEE 696 S- 100 Two RS232 Serial Ports Baud Rates from 50 to 19200 Baud Independent Baud Rate for each Serial Port 24 Parallel 1/0 lines (Three 8 Bit Pprts) Attractive Industrial Quality Enclosure TEC-86M4 — $7595. FOUR USER TEC-86 SYSTEM WITH V? MEGABYTE OF MEMORY TEC-86 W — $10990. 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OTHER FINE SI 00 and APPLE PRODUCTS AVAILABLE, INCLUDING: accuracy, 30, 40, 100, 125 KHz Conversion rates, 16 to 256 Channels, programmable ANALOG to DIGITAL CONVERTERS (12, 14, 16 bit gain, timer/ counters). DIGITAL to ANALOG CONVERTERS (12 bit accuracy, 3 microsecond conversion rate), 64K/256K Memory Boards, Real-time Video Digitizer and Display. Complete Systems also available Digitization, and General Purpose Applications. REQUEST OUR CATALOG FOR COMPLETE LISTING, AND SPECIFICATIONS ON THE ENTIRE TECMAR PRODUCT LINE. 8086 CPU Board, I/O Boards for Data Acquisition, Video EC HR DEALER INQUIRIES INVITED 23600 Mercantile Rd. Cleveland, OH 44122 TECMAR, INC. (216)464-7410 > I Listing 2 continued: BLOCK 8 28 (" FORTHDOS DEMO 7 (C) Peter R®®c& 1981" : RENAME DGTMAF N 3 20 -■ M ! MSB DTNM " to be renamed SPACE Zi'AR AR1 15 EXPECT 15 O DO I AR1 D3> M a I as: " C ! LOOP AR1 FNAME 15 MOVE MSB ; RG 1-SB Ca RDBK ! I) UP 16 / DUP > IF DO 1 RDBK + ! : SHOW MSG NAME LOOKUP 255 C$ P ! RDBK 3 Q ! RREC C! 2KEY BREAK ' 1 PFILE MSG " DONE" CMSG s DUP 16* ROT SWAP - RREC C! GRDBK LOOP ELSE DROP THEN jj > IF FSZ1 0* BM1 C3 > AND 3 1STBK CLS BEGIN DSKIO CR EOF OR END P $ RREC QJ 3 RDBK ! EOF C! THEN Enable the printer" CMSG PORT SHOW CRT ; F RREC THEN j 3 + g DUP : E0F2 FSZ1 DROP K ! Fl C8 BLOCK N ! 15 DO I 16* N 3 Co) 127 - IF I K ! LEAVE THEN LOOP FSZ1 DROP BM1 C$ 16* K : EOFMSG MSG " Last record i'S #" EOF? T# SPACE DTNM CMSG g RREAD MSG " Record number:" RDBK 5) Q ! RREC CS P ! #IN EOF? > IF MSG » Pa sit boP 1 DROP CMSG ELSE RG MSG DSKIO P a RREC C! Q a RDBK ! 14 40 PTC ENTER THEN j BLOCK B 27 <" FGRTHDOS DEMO 8 - (0) Peter Reece 1981" g FILES FNAME AR2 15 MOVE DADRS 3 128 + K ! CLS 23 PTC " Disk Directory" CR DADRS a 64 + 50 TYPE CR 12 DO K a Ca <> IF K a FNAME 15 MOVE FNAME 15 TYPE 10 SPACES FSZ1 0* IF BM1 G8 16* T# SPACE " records" LOOKUP DROP RENM N a 63 + Ca 170 » IF 5 SPACES " Write protected" THEN CR THEN THEN 64 K 4-! LOOP AR2 FNAME 15 MOVE FREE :; : DSET MSG " Build a new directory" Y/N NOT IF CLS MSG DINI'T DON 1 DON DADRS a 1024 FILL MSG " Description:" SPACE AR1 60 EXPECT AR 1 DADRS 3 64 + 60 MOVE 42 DADRS a 20 * 5 FILL DSAVE ELSE THEN ; g GDSK MSG " INSERT DATA DISK" CMSG PBLK ! MOUNT DADRS a 20 ■•>■■ &8 42 <> IF CLS 23 ECHO CR CR 5 SPACES " UNINITIALIZED DISK" DSET THEN i: . PR0T MSQ .. F > rotect n I3TNM look.; UP 255 <> IF Y/N NOT IF RENM 170 N a 63 4- C! ELSE RENM N a 63 + C! THEN ELSE MSG " NO SUCH FILE" THEN CMSG ; block; g 28 (" FORTHDOS DEMO 9 - (C) Peter Reece 1981" ( * These r o u t i n e i pi r form w r i t e o p #r a t i a n m * ) : WCK 1 RREC C+ ! RREC Co) 15 > IF RREC C 1 1 RDBK *! PSZ1 DROP Fl Ca RDBK a < IF DADD RDBK ! THEN THEN j : WSHOW K a 15360 1024 MOVE MSG " BLOCK:" RDBK a T# 8 : WRIT El 1SB Ca 0= IF DADD DUP 1SB C! RDBK ! RREC C! THEN RDBK a BLOCK K ! WSHOW AR1 RREC Ca 64* K a ■+■ 64 MOVE RENM N a 63 + Ca 170 = IF MSG " Write protected" ELSE K a RDBK $ WBLK WSHOW FLUSH WCK MSG " Written to r®c%" THEN NREC ; j WRITE MSG " Write what::" SPACE Z1AR AR1 64 EXPECT WRIT El g g R WRITE MSG " Record tt" RDBK a Q ! RREC Ca P ! WIN DUP > IF 1 THEN DUP EOF? > IF MSB " Past eof " DROP ' CMSG ELSE RB MSG DSKIO DELAY WRITE THEN ; ( # More menu commands- ) : MENU1 13 PTC " 23 Write EOF mark" 13 32 PTC " 24 END this demo" g BLOCK : 29 (" FORTHDOS DEMO 10 - (C) Peter Reece 1981" ( * Open or create a file.) ; MAKE 1SB C! NAME DPUTNM RREC G! 1STBK ; < * Copy a file to another file, same disk,) : FCOPY MSG " COPY FILE" DELAY Z1AR FNAME AR1 15 MOVE EOF? 16 / K ! 1SB C! EOF C! MAKE FNAME AR2 15 MOVE AR1 FNAME 15 MOVE ZPNTRS WHILE K PERFORM AR2 FNAME 15 MOVE AR1 FNAME 15 MOVE MSG " FROM BLOCK" RDBK PEND AR1 FNAME 15 MOVE EOF C MSG " COPY COMPLETED" CMSG ; CBLK MSG " To max space: select #'. " type ' FORGET DOS 52 LOAD 1 " 1 CMSG a > M a -1 <> AND 7KEY BREAK <> AND 15360 RDBK a RBLK 15360 DADD WBLK FLUSH 1 RDBK t! GRDBK Ca Ttt DELAY 1 K ~! M ! ZPNTRS CLS 4, " SPACE BLOCK : 30 <" FORTHDOS DEMO 11 ! MENU TITLE 2 PTC " UNMOUNT a disk" 32 PTC " 4 - CLOSE 32 PTC " 6 - Seq WRITE a file" 5 SPACE " (CLEAR to stop)" 5 32 PTC " 9 - Random READ a record" 6 32 SPACE " WRITE a record" 7 PTC 7 32 PTC " 12 - KILL a file" 8 SPACE M FREE disk space" 8 32 PTC (C) Peter Reece 1981" " I - MOUNT a disk" 2 32 PTC " PTC " 3 -■ OPEN (or create) file" 4 PTC " 5 - Seq READ - " SPACE file" 3 file" 4 PTC " 7 ■■■- LIST a file" " 8 - LIST blacks" 6 PTC PTC " 10 -- Random" 11 - RENAME a file" PTC " 13 - Show" 14 Show disk DIRECTORY" 9 PTC " 15 - COPY to another file" 9 32 PTC " 16 - COPY" SPACE " sequential blocks" 10 PTC " 17 - PRINT a file" 10 32 PTC » 18 - RESET Seq File to Beqininq" 11 PTC " 19 - Write PROTECT a file" 11 32 PTC " 20 - Show file SIZE" 12 PTC " 21 - CURRENT seq r^c number" 12 32 PTC " 22 - Find LAST record" MENU1 MSG " Which number:" g BLOCK I " FORTHDOS DEMO 12 ENDIT -5 M ! ; RESET MSG EOF C WEOF MSB " Write 127 AR1 C! 127 1 AR1 * Command driver rests FORTHDOS PBLK ! BL BEGIN MENU M ! 15 46 NCASE 1 2 3 9 10 11 17 18 19 GDSK REMOVE RREAD RWRITE PFILE RESET CASEND M a ■-5 m END CLS 8 17 PTC " END (C> Peter Reece 1981' ZPNTRS MSG DTNM SPACE " reset" DELAY of to current record" Y/N NOT IF C! WRIT El THEN CMSG :: here. ) FNAME 15 FILL Z1AR ZPNTF S PTC DTNM 15 16 PTC ttIN 4 5 6 7 8 12 13 14 15 16 20 21 22 23 24 " MAKE CLOSE READ WRITE SHOW BLOCK RENAME KILL FREE FILES FCOPY CBLK PROT FSIZE NREC EOFMSL WEOF ENDIT OF FORTHDOS DEMO" 15 PTC g BLOCK (2b) H ( 1 DRIVE BLOCK COPY I C ARRAY CCONSTANT VARIABLE K K a CONSTANT MAXSZ VARIABLE FROM : READ CLS 10 PTC WHILE M a MAXSZ < FROM a RBLK 1024 N : WRITE CLS 10 PTC ! ENTER N ! WHILE N a MAXSZ < K $ TO £ >■« TXT TO a WBLK 1024 N + ! 12 PTC " >« TO : CYCLE WHILE K S> TO a >■ PERFORM READ WRITE : START' CLS 5 PTC " Start Block*" #1N FROM #IN END ! CR " Destination Block*" #IN TO TO a + K f CR CYCLE CLS " **Done to" TO a START FORGET TASK PETER REECE /BO) : TASK ; * ' ; CODE HL POP DE DAD PSH PAD 1024 / 1024 * 1024 K ! MAXSZ CARRAY TXT VARIABLE N VARIABLE END VARIABLE TO 3 ECHO " Insert SOURCE disk" ENTER END a FROM a >* AND PERFORM N a TXT 12 PTC FROM ? " ->" ! FROM + ■! PEND ::; h o ' ' :i: n g & r t D e s t t n a t i o n d i s k ■ ■ AND PERFORM N a '? 1 TO +' PEND :; N ! PEND :; 1 CR " End Block* ! END a FROM a 1 - * " **" CR 5 E CQMPLJTRQNICS C. EVERYTHING FOR YOUR TRS-80* • ATARI* • APPLE* • PET* • •TRS-80 is j trademark of the Radio Shack Division of Tandy Corp. - 'ATARI is a trademark of Atari Inc. - *Apple is a trademark of Apple Corp. - "Pet is a trademark of Commodore BUSINESS PAC 100 100 Ready-To-Run Business Programs ^fltt u;« 24-HourS Software (ON CASSETTE OR DISKETTE) Includes 1 10 Page Users Manual 5 Cassettes (Or Diskettes) Inventory Control Payroll Bookkeeping System.. ...Stock Calculations Checkbook Maintenance... ..Accounts Receivable.,.. Accounts Payable BUSINESS 100 PROGRAM LIST 1 RULE78 Interest Apportionment by Rule of the 78"s 2 AMNCJ1 Annuity computation program 3 DATE Time between dates 4 DAYYEAR Day of year a particular date falls on 5 LEASEINT Interest rate on lease 6 BREAKEVTH Breakeven analysis 7 DEPRSL Straightline depreciation 8 DEPRSY Sum of the digits depreciation 9 DEPRDB Declining balance depreciation 10 DEPRDDB Double declining balance depreciation 1 1 TAXDEP Cash flow vs. depreciation tables ] 2 CHECK2 Prints MEBS checks along with dairy register 13 CHECKBK1 Checkbook maintenance program 14 MORTGAGE/ A Mortgage amortization table 1 5 MCILTMOM Computes time needed for money to double, triple, 16 SALVAGE Determines salvage value of an investment 1 7 RRVARJM Rate of return on investment with variable inflows 18 RRCOMST Rate of return on investment with constant inflows 1 9 EFFECT Effective interest rate of a loan 20 FVAL Future value of an investment (compound interest) 21 PVAL Present value of a future amount 22 LOAMPAY Amount of payment on a loan 23 REG WITH Equal withdrawals from investment to leave over 24 SIMPDISK Simple discount analysis 25 DATEVAL Equivalent & nonequivalent dated values for oblig. 26 ArHMCJDEF Present value of deferred annuities 27 MARKUP % Markup analysis for items 28 SINKFCJND Sinking fund amortization program 29 BONDVAL Value of a bond 30 DEPLETE Depletion analysis 31 BLACKSH Black Scholes options analysis 32 STOCVAL1 Expected return on stock via discounts dividends 33 WARVAL Value of a warrant 34 BOMDVAL2 Value of a bond 35 EPSEST Estimate of future earnings per share for company 36 BETAALPH Computes alpha and beta variables for stock 37 SHARPE1 Portfolio selection model-i.e. what stocks to hold 38 OPTWRITE Option writing computations 39 RTVAL Value of a right 40 EXPVAL Expected value analysis 4 1 BAYES Bayesian decisions 42 VALPRIhF Value of perfect information 43 VALADINF Value of additional information 44 UTILITY Derives utility function 45 SIMPLEX Linear programming solution by simplex method 46 TRANS Transportation method for linear programming 47 EOQ Economic order quantity inventory model 48 QUEUE1 Single server queueing (waiting line) model 49 CVP Cost-volume-profit analysis 50 COMDPROF Conditional profit tables 51 OPTLOSS Opportunity loss tables 52 FQUOQ Fixed quantity economic order quantity model NAME DESCRIPTION 53 FQEOWSH As above but with shortages permitted 54 FQEOQPB As above but with quantity price breaks 55 QUEUECB Cost-benefit waiting line anafysis 56 NCFANAL Net cash-flow analysis for simple investment 57 PROFIND Profitability index of a project 58 CAP1 Cap. Asset Pr. Model analysis of project Circle 191 on inquiry card. 59 WACC Weighted average cost of capital 60 COMPBAL True rate on loan with compensating bal. required 61 DISCBAL True rate on discounted loan 62 MERGANAL Merger analysis computations 63 FINRAT Financial ratios for a firm 64 NPV Net present value of project 65 PRINDLAS Laspeyres price index 66 PRINDPA Paasche price index 67 SEASIND Constructs seasonal quantity indices for company 68 T1METR Time series analysis linear trend 69 T1MEMOV Time series analysis moving average trend 70 FUPR1NF Future price estimation with inflation 71 MAiLPAC Mailing list system 72 LETWRT Letter writing system-links with MAILPAC 73 SORT3 Sorts list of names 74 LABEL I Shipping label maker 75 LABEL2 Name label maker 76 BCISBUD DOME business bookkeeping system 77 TTMECLCK Computes weeks total hours from timeclock info. 78 ACCTPAY In memory accounts payable system -storage permitted 79 INVOICE Generate invoice on screen and print on printer 80 INVENT2 In memory inventory control system 81 TELDIR Computerized telephone directory 82 TIMUSAN Time use analysis 83 ASSIGN Use of assignment algorithm for optimal job assign. 84 ACCTREC In memory accounts receivable system-storage ok 85 TERMSPAY Compares 3 methods of repayment of loans 86 PAYNET Computes gross pay required for given net 87 SELLPR Computes selling price for given after tax amount 88 ARBCOMP Arbitrage computations 89 DEPRSF Sinking fund depreciation 90 UPSZONE Finds UPS zones from zip code 91 ENVELOPE Types envelope including return address 92 AUTOEXP Automobile expense analysis 93 INSF1LE Insurance policy file 94 PAYROLL2 In memory payroll system 95 DILANAL Dilution analysis 96 LOANAFFD Loan amount a borrower can afford 97 RENTPRCH Purchase price for rental property 98 SALELEAS Sale- leaseback analysis 99 RRCONVBD Investor's rate of return on convertable bond 100 PORTVAL9 Stock market portfolio storage-valuation program D CASSETTE VERSION D DISKETTE VERSION $99.95 $99.95 NEW ORr> T £ LF »E£ TRS 80* MODEL II VERSION $149*95 (Outs^ ^'Nf ADD $3.00 FOR SHIPPING IN UPS AREAS (8dt\\ Jt *% ' ST *T£) ADD $4.00 FOR C.O.D. OR NON-UPS AREAS f VV / ^OT-OO-f ft ADD $5.00 OUTSIDE U.S.A, CANADA & MEXICO <0 f ' Now! An Acoustic Coupler for $125. The Omnitec Model 715 {originate only) has the necessary features, needed to expand any business or home computer systems capability: 0-450 baud data rate, RS232 compatibility and carrier detect at a low factory-direct price of $125. Or, select the Model 770 s\? at $179.00 for originate or answer communications. A Both models carry a one year warranty. tfjjjN OMNITEC DATA J& \JH|/ 2405 South 20th Street • Phoenix, Arizona 85034 \j ^ PRICES INCLUDE SHIPPING & HANDLING WHEN PRE-PAID J> 350 April 1982 © BYTE Publications Inc Circle 306 on inquiry card. Put your business forms on an Apple II An innovative software system that speeds the processing and analysis of common business forms on a personal computer. VersaForm applications include: • Invoicing • Order purchasing Hard Disk • Purchase orders • Sales analysis Versions • Client billing • Personnel records Available • Mailing lists • Inventory records VersaForm fafiM Business Form Processor ■d* Appi iea 15985 Greenwood Rd SOT tWarG Monte Sereno, California 95030 Technology (408) 395 " 1541 Circle 39 on inquiry card. The manner in which FORTHDOS determines whether a given record bit in the file bit map is a 1 is interesting, given that FORTH is a high-level language which lacks bit manipula- tion capability. To do this, FORTH- DOS makes use of three primi- tives— DON ,{ DON? } , and DOFF . ["Primitive" here means an MMSFORTH word that performs an elementary function frequently used by later words in the system. . . . GW] Since these three primitives are used by practically every other primitive in FORTHDOS to deter- mine record status, it will be useful to investigate their use. Determining Record Status Look at the DON, DOFF, and DON? primitives in the program listing; then look at figure 9. In the example, DON (disk access on) turns on the bit in the bit map which cor- responds to the record number being accessed by the file. This means that the file now "owns" that record, and no other file may write to it unless it is reclaimed by the DOFF (disk access off) primitive. DON? is used to return the record's status (on or off) to other primitives. For instance, DNXT makes frequent use of DON? to scan the DOS bit map when seeking a free record to give to a file. These three primitives translate the calling record number according to the following formula: -*[mod r/n] where r is the record number, n is the number of bytes in the file bit map, and [mod (r/n)] is the remainder of dividing rbyn. This has the effect of translating the calling record number into a power of 2 and hence into a bit position within the 11 bytes of the bit map. (In the FORTHDOS listing, 8 bytes are used simply because that is how my own personal system is set up.) You might argue that it is easier and faster to resort to machine language and simply use a bit rota- tion command to access more rapidly the status of the appropriate bit. However, for the purposes of main- taining generality in this article I have instead given a high-level language solution in the listing. It works almost as well as a machine-language im- plementation of this part of FORTH- DOS. You can translate the com- mand to the lower-level language of your choice if you wish to increase the overall speed of FORTHDOS through these central primitives. File Deletion and Allocation Having followed the development of FORTHDOS thus far, you should have a pretty good idea of the strategies used, but let's review a couple of points for further clarifica- tion. As mentioned earlier, many DOS systems use an allocation scheme to adjust file space periodical- S c i T R N I C s I N C. -100 INNOVATORS: REMOTE CONTROLLER-lnnovative Features: * Complete 256 address control— not just 16 *No ultrasonic link— prevents erractic operation * 120,208,240 and 277VAC control— for single & 3 phase operation * Hardware driven— requires minimal software *Comp!ete line of industrial switches available— to 5.5KW REAL TIME CLOCK- Innovative Featuers: * First to use LSI OKI clock chip *Crystal controlled for .002% accuracy *4 software selectable clock generated interrupts * Full clock and calendar data * Lithium battery backup good for 6000 hours! ENERGY WATTCHER -Innovative Features: * First microcomputer based energy monitor *Clip on probes for easy installation * Monitors Real Power, not volt-amps *Peak Power and continuous power readings * Single and 3 phase operation See your local computer dealer or contact SciTronics directly for more information. Watch for future innovative products from SciTronics Inc., 523 So. Clewell St., P.O. Box 5344, Bethlehem, PA 18015 (215) 868-7220 352 April 1982 © BYTE Publications Inc Circle 364 on inquiry card. IM\/C0B0i: MAKES IT ACROSS! ...FROM ONE OPERATING SYSTEM TO ANOTHER! A VITAL WAY TO PROTECT YOUR SOFTWARE INVESTMENT FOR THE FUTURE!! The It At/MIKOL language runs on more different Operating Systems and more different-sized computers than any other similar language. For starters, it runs on NCR and TI minicomputers and, in the micro field, on the CP/M 2 , MP/M 2 , CP/M86 2 , MP/M-86 2 , TRSDOS 3 , OASIS 4 , MOASIS 4 . and UNIX 5 . (ONYX version] Operating Systems ... to mention only a few. KM /COBOL and } construct in FORTH. • The MMSFORTH word { " }, when used at the beginning of a string to be printed, is replaced by { ." } in fig- FORTH. mThe{ NCASE ... " ... CASEND } construct is best explained by example. The FORTH phrase { NCASE 22 60 114 " WORD22 WORD60 WORD114 CASEND }. If the number on top of the stack is 22, the word CASE22 is ex- ecuted; if it is 60, CASE60 is executed; if it is 114, CASE114 is executed. If the number is not any of these, control passes to the word after CASEND . One simple though inelegant substitu- tion is a series of nested IF statements. • The MMSFORTH { BEGIN ... END } construct is equivalent to the fig-FORTH { BEGIN... UNTIL } construct. • The MMSFORTH word Y/N prints "(Y/N)?" and waits until either the Y or N key is pressed. In the former case, a 1 is put on the top of the stack; in the latter, is put on top of the stack. I hope the above information makes the conversion easier GW I ■■ ■ MOUNT a disk 2 - UNMOUNT a disk 3 - ■ OPEN (or create) a f 1 J e 4 - CLOSE a tile 5 - ■ Seq READ a file 6 Seq WRITE a file 7 - • LIST a file (CLEAR to stop) 8 - LIST blacks 9 . - Random READ a record 10 - Random WRITE a record 11 - RENAME a file 12 - KILL a file 13 - Show FREE disk space 14 - Show disk: DIRECTORY IS - COPY to another file 16 - COPY sequential blocks 17 - PRINT a file IS - RESET Seq File to Beqininq 19 - Write PROTECT a file 20 - Show file SIZE 21 - CURRENT seq rec number 22 - Find LAB"!' record ' ; ..\ - Write EOF mark 24 » END this demo Which number: Figure 12: Screen display of commands for the FORTHDOS demonstration program. link-listed chain, if one record in the chain is lost (the unhappily common lot of small systems) the entire chain integrity is lost. FORTHDOS keeps all file-record pointers in a memory- resident bit map (a copy of which is stored on the disk), thereby largely avoiding this problem. The third problem: excessive head movement occurs if files are killed as described above. The solution is to reallocate space on a disk. As figure 11 indicates, the head-movement problem seems likely to occur with most DOSes. Mainframe vendors have hit upon the solution of periodically reallocating disks to decrease the number of non- contiguous records. The method, used by mainframe computers, involves gathering records scattered throughout the disk into an unused portion of that disk. (These portions are contiguous.) Then the original file(s) is destroyed, and the new file, now in a contiguous area, is used. (Actually, more com- plex methods are applied, but this is the essence of the scheme.) FORTHDOS uses a similar system. If the disk heads seem to be moving excessively (listen to them) while typ- ing a file, or if FORTHDOS returns from a disk-write operation with the THREAD FULL message, it is pro- bably time to use the FORTHDOS utility FCOPY (or XCOPY or BCOPY; see table 1). Reallocating with FCOPY is simple enough. Assuming enough contiguous records are on the disk to hold the file you are copying, FCOPY will pull all the records from a scattered file and neat- ly place them within the new file area in close physical proximity. It will then KILL the old file. The file will have been reallocated to a contiguous area on the disk, which will probably relieve disk-head movement and file- full problems. This very simple technique can be done to all files on a disk by simply FCOPYing a disk full of files to an empty disk. The new disk will then consist of files whose records are all in contiguous areas. This solution to the allocation problem is easy to per- form and memory efficient; if done periodically, it will speed up your disk operation. FORTHODS in Use By now, you should have a suffi- ciently good idea of how FORTH- DOS works to be able to use the listing to understand the workings of other commands and features. We can now look at an actual application of FORTHDOS. Assuming FORTHDOS has been loaded into RAM, you would first MOUNT a formatted disk and in- teractively initialize it by issuing the SETDIR command. Next, you might create a file for further use by issuing the MAKE command either from the terminal or through transparent calls from a program. Having created some files, you might next write in- formation to one of them sequentially by filling the I/O buffer BUFF and making repeated calls to WRITE. This would probably be done through calls to FORTHDOS from within a user program. To look at the contents of the file(s) just written, issue a TYPE command from your program or directly from the terminal. To get a formatted listing on the system printer, you can make a call to the PTYPE utility, which would output the file to the printer with page numbers, titles, etc. At this point, you may wish to 356 April 1982 © BYTE Publications Inc Circle 410 on inquiry card. « BATTERIES AND BULBS is just one of the many bright ideas developed by Alfred Bork and the staff of the Educational Technology Center at UCI. This computer-based learning program makes exten- sive use of graphics to lead the student through an empirical investigation of electrical circuits using observations simulated on the com- puter. The computer dialogs for Batteries and Bulbs, as with other UCI-developed course material, is designed to work for students of all ages. Some build intuition, some aid reasoning capability and some increase understanding of science. The material was developed on a Terak 8510/a, a complete black and white graphic computer system that is compatible with DECs PDP-11 series of minicomputers. The 8510/a offers a high degree of interactivity flexibility of dis- play format (characters and graphics can be mixed and controlled independently) and animation capability In fact, no other graphic computer system offers the com- bination of features that UCI found in the Terak 8510/a. So, if you're in the market for bright ideas, we'll be happy to send you a list of the computer- based learning material available from UCI's Educational Technology Center. Or, if you're creating your own, we'll send you complete information on Terak graphic computer systems. / . .is it ■ ? Dr. Alfred Bork, Director Educational Technology Center University of California, Irvine The Leaders In Instructional Computer Graphics i CORPORATION 14151 North 76th Street, Scottsdale, Arizona 85260 • (602) 998-4800 query the disk contents so far. To do this, you type FILES; file names, sizes, space allocations, comments, free space, RAM usage, time of day, etc. will appear on the terminal. To protect any files from subsequent in- advertent writing by a program, you could type PROTECT plus the file name. No further writing could then be done to the protected file until UN- PROTECT was issued for that file. Suppose a disk hardware error oc- curred during a WRITE, putting bad data and checksums into a record. To prevent FORTHDOS from accessing that record in the future, the LOCK command could be given. This would lock out that record from any subse- quent read/write operations by FORTHDOS. To make a backup of a file, you could issue the FCOPY com- mand (or XCOPY if copying to a dif- ferent disk on the same drive), which will prompt for information prior to automatically performing the copy. Now that a copy has been made, you might wish to rename some of the old files. To do so, you would issue the RENAME command for a given file. At this point, you might wish for help with the FORTHDOS commands. Assistance can be obtained at any time by simply typing HELP on the terminal or from within a program. The preceding discussion should give you some idea of the actual usage of FORTHDOS. The other commands in the system are just as easy to use. Some are issued from user software, some by you directly, and others transparently without your knowledge. At the end of the session, you must type REMOVE (or have your program call the primitive DSAVE) to ensure that the directory will be saved to disk. Conclusion FORTHDOS is a simple but effec- tive single-user DOS. Since it is modular, only the modules required for a given application need to be stored in RAM. This makes FORTH- DOS a "tight" and straightforward system. For all its simplicity, it gives the FORTH user all of the capabilities found in most microcomputer DOSes but without the disadvantages of complex structures or high system overheads. I have been using FORTHDOS for over a year now. Most of its use has been as an integral part of a word processor (which I used, among other things, to write this article). Even after a year of considerable use, I have found no errors in the software, and it gives me all the advantages of a conventional DOS with none of the disadvantages of the traditional "blocks" storage system in FORTH. An added feature: this system re- mains compatible with the concept of blocks. At any time, I can still edit any block of a file with a conven- tional FORTH block editor. FORTHDOS is easily understood (after a little study and experimenta- tion) and easily modified to suit your needs. I hope that you will find it as practical and enjoyable as I have.B INDUSTRIES, INC. In Texas Orders Questions & Answers 1-713-392-0747 21969 Katy Freeway Katy (Houston) Texas 77450 To Order 1-800-231-3680 800-231-3681 SAVE BIG DOLLARS ON ALL TRS-80 HARDWARE & SOFTWARE TRS-80 BY RADIO SHACK. Brand new in cartons delivered. Save state sales tax. Texas residents add only 5% sales tax. Open Mon.-Fri. 9-6, Sat. 9-5. We pay freight and insurance. Come by and see us. Call us for a reference in or near your city. Ref: Farmers State Bank, Brookshire, Texas. WE OFFER ON REQUEST Federal Express (Overnight Delivery) Houston Intercontinental Airport Delivery (Same Day) U.P.S. BLUE (Every Day) References from people who have bought computers from us probably in your city In stock TRS-80 Model II and III No Tax on Out of Texas Shipments! * TRS-80 is a Registered Trademark of Tandy Corp ED McMANUS » 10% 15% OR MORE We Specialize In Overseas Shipments Telex 77-4132 (FleksHou) WE ALWAYS OFFER NO extra charge for Master Card or Visa. We use Direct Freight Lines. No long waits. We always pay the freight and insurance Toll free order number Our capability to go to the giant TRS-80 Computer warehouse 5 hours away, in Ft. Worth, Texas, to keep you in stock. JOE McMANUS 358 April 1982 © BYTE Publications Inc Circle 247 on inquiry card. Programmers The Environment is the Message Our Climate Encourages Creativity . . . Inside and Out At TT1, our environment inside and out stimulates the creative technical thinking that sets us apart from the rest We can't of course take credit for the year-round sunshine and the warm ocean breezes -- What we can take credit for is the careful con- struction of an internal climate that does for the professional spirit what sunshine does for the personal one Backed by Citicorp, with over $100 billion in assets, our re- sources enable the development of sophisticated systems, create access to the most advanced equipment available, and provide individual computer terminals. If you're a professional seeking a change of climate inside and out consider working on the design and development of ad- vanced computer systems and networks at a company thaf s rev- olutionizing the banking industry all over the world. PROGRAMMING ANALYSTS Will design and develop on-line trans- action processing systems 5-10 years experience in several of the following areas required: operating systems; structured system design; on-line transaction processing (e.g.. CICS, ENVIRON I, GEMCOS); distributed networks (e.g., Tandem, HP, PE, DEC); or systems documentation. Assembly language or COBOL pre- ferred DATA BASE PROCESSOR DEVELOPERS Design and develop a high through- put high reliability Data Base Man- agement System The Data Base Proc- essor consists of multi- super- mini's and various intelligent peripherals utilizing PASCAL Requires 5-8 years experience in several of the foil ow- ing areas: data base management sys- tems; operating systems; compiler development; or system utilities. SOFTWARE ARCHITECTS Design architecture for an on-line real-time transaction- oriented system. Expertise in the design of a large-scale, multiple release, software system such as ticketing, reservations, financial trans* actions, and or information network systems -- especially in a distributed mini- communications network environment, COMMUNICATIONS SOFTWARE DESIGNERS Will design front end processors and communication networks. Requires 5+ years experience in telecommunications software, both networking and protocol definition. TEST AND INTEGRATION ANALYSTS A background in software and systems testing methodology for large-scale systems. Prefer 2 years on-line programming experience. MICROPROCESSOR DESIGNERS Design and implement applications on microprocessors or home com- puters. Requires 5- 10 years design and programming experience; mini- mum one year experience with micro- processors, ( preferably 6S02 or 8080/280/8086 assembly" language). TTI offers one of the finest salary, benefits and vacation plans in the industry, relocation assistance med- ical and dental insurance, financial services, a van pool from most out- lying Los Angeles areas, and a special health club membership Forward your resume to: Professional Staffing TRANSACTION TECHNOLOGY INC 3100 Ocean Park Blvd. DepL BY-4/82 Santa Monica, CA 90405 777- Designing the future of banking . . . for the world TTI An Equal Opportunity Employer M/F/H CITICORP © Circle 403 on inquiry card. BYTE April 1982 359 Now you can do oil the f ilingjy ping and Silicon Office is the latest microcomputer oftware program from the Bristol Software Factory. Designed specifically for use with the Commodore PET 8096, it'll help you run your office vith the minimum amount of effort and maximum efficiency. Think of it like three normal software packages n one, each separate package totally interactive with he other. For around $7,000, you can have the complete electronic office, the solution to practically all your >usiness problems. The price includes Commodore lardware, a high quality daisy wheel printer and Jilicon Office software. Silicon Office is made up from a flexible nformation management system which lets you create and maintain an extensive filing arrangement. Allowing you to search quickly through your records, making cross references between files in order to gain the facts you require. A highly sophisticated word processing program allows you to generate letters, documents and reports. Letting secretaries get on with the more important tasks. And a fully comprehensive calculator means you can handle all the number crunching you're ever likely to do in a business situation. Leaving the accounts department to concentrate on more profitable things. But that's not all by any means. Silicon Office also has a special programmability feature which means you or your dealer can expand and tailor the Silicon Office program to your business. When Silicon Office is used in an everyday business situation, certain command sequences are inevitably repeated. By writing short, very simple programs which are entered into the computer's memory, Silicon Office can perform the necessary tasks, automatically. And last, but by no means least is an optional communications facility. It doesn't take much imagination to see the potential of Silicon Office in virtually any line of business. So to get a better grasp, send away for our brochure. It'll only cost you a stamp. And it could save you a fortune. Or talk to your local Commodore dealer who has all the facts at his fingertips. You'll soon see how you're much better off with Silicon Office. Than without. Circle 60 on inquiry card. IILIEDN DfflU ■^ I can't wait to get my hands on a free copy of the Silicon Office brochure. Name i Position- Company- Address A-BY1 I own a Commodore PET (Please tick box) YESn NOD Send to: The Bristol Software Factory, c/o Associated Marketing Systems Inc., 55 Central Drive, Farmingdale, New York NY 1 1 735 Technical Forum MicroShakespeare 3 Andrew Kalnik 3201 Wamath Drive Charlotte, NC 28210 The substitute instructor walks into your programming class wearing a ruffled collar. You enrolled in evening courses at Avon Community College hoping that the ses- sions would be intellectually stimulating. Your expecta- tions are high; this instructor is, well — very interesting. The spade beard is common enough, but his long, velvet-trimmed coat and high stockings resemble the garb Errol Flynn wears in the old movies. Everything comes together when the instructor turns to sign his name for the class to see. You recognize the script with the ornamental scrollwork under it and realize that if you can only walk away with that autographed slab of chalkboard, you can sell it for millions. The substitute in- structor has signed William Shakespeare. He tells you to call him "Master Will." He says he comes from Stratford — just down the road. His opening remarks come in an Elizabethan accent . Master Will tries to encourage the class: "...We were not born to sue, but to command...." (Richard 11, Act I, scene i) Continuing, he says he knows that you all have prob- lems making your computer systems do what you want: "...I see your brows are full of discontent, Your hearts of sorrow...." {Richard II, IV, i) "...You know not what you do...." (Romeo and Juliet, I, i) The instructor of Avon has no doubt that you can all put your systems in good order. He stresses that he doesn't want to make Much Ado About Nothing but that attention to detail is important. He's sure that you'll be careful not to write any self -destroying programs, and thus you'll avoid having your Love's Labours Lost. Master Will suggests the class talk over its program- ming difficulties. Bring on your problems, he says. He en- joys challenges: "The bugs which you would fright me with I seek...." (The Winter's Tale, III, ii) Master Will's confident air makes you certain that he'll be able to help. He assures you that he can show you useful programming techniques: "...make that appear where it seems hid..." (Richard III, I, ii) His slightly bulging eyes seem melancholy and very wise as he inspects the flowcharts he has asked you to draw as an exercise: "...leave these sad designs..." (Richard III, I, ii) You feel better after he marks your block diagram with a few strokes of his quill pen. Now, he says, "...What thou woulds't it do Is done into thy hand...." (Antony and Cleopatra, IV, xiv) As he leaves (erasing the chalkboard and with it your dreams of avarice), his words fill you with enthusiasm for the nearly limitless horizons of microcomputing: "...and the end of it Unknown to the beginning...." (Coriolanus, III, i) He leaves a little quiz scratched in that old-fashioned script. Let's see if you paid attention to what Master Will taught. We've collected some of his writings and translated them into modern computing terms. All you need is a sharp quill and brain. Match each Shakespearean quote on pages 364 and 366 with the most pertinent modern phrase. Only you will know whether you have ended up As You Like It or in the middle of The Comedy of Errors. The answers and Micro Shakespeare ratings are on page 374. /Editor's note: Each of the items 1 through 20 matches one of the answers "a" through "t," so read through all the answers before you attempt a match... PL/ 362 April 1982 © BYTE Publications Inc CSunS >"J»rp re ** v « ! WiG/NNER'S GUH3f; kqrthe i SYSTEM BASIC Scientific Subroutines, Vols. I and II Valuable programs for professional and hobbyist by Fred R. Ruckdeschel Designed for the engineer, scientist, experimenter, and student, this series presents a complete scientific subroutine package featuring routines written in both standard Microsoft and North Star BASIC. • Volume I covers plotting, complex variables, vector and matrix operation, random number generation, and series approximations. • Volume II includes least- squares approximation, special polynomial functions, approximating techniques, op- timization, roots of functions, interpolation, differentiation, and integration. Volume I ISBN 0-07-054201 -5 336 pages; hardcover 19.95 Volume 11 ISBN 0-07-054202-3 800 pages; hardcover 23.95 Threaded Interpretive Languages How to implement FORTH on your Z80 by Ronald Loeliger This book develops an inter- active, extensible language with specific routines for the Zilog Z80 microprocessor. With the core interpreter, as- sembler, and data type defin- ing words covered in the text, it is possible to design and implement programs for al- most any application and equivalent routines for dif- ferent processors. ISBN 0-07-038360-X 272 pages; hardcover 18.95 Beginner's Guide for the UCSD Pascal System The most popular Pascal version ex- plained by its creator by Kenneth L. Bowles Written by the originator of the UCSD Pascal System, this informative book is an orien- tation guide to the System. The hard facts about Software from Byte Books For the novice, this book steps through the System, bringing the user to a sophis- ticated level of expertise. Once familiar with the System, the reader will find the Guide an invaluable reference tool for creating ad- vanced applications. ISBN 0-07-006745-7 204 pages; softcover 11.95 The BYTE Book of Pascal A powerful, structured language Blaise W. Liffick, Editor Based on articles, language forums, and letters from BYTE magazine, this work is a valuable software resource. Pascal continues to be popular as a structured pro- gramming language. Written for both potential and established users, this book introduces the Pascal language and examines its merits and possible implementations. Featured are two versions of a Pascal compiler, one written in BASIC and the other in 8080 assembly language; a p-code interpreter written in both Pascal and 8080 assembly language; a chess- playing program; and an APL interpreter. ISBN 0-07-037823-1 334 pages hardcover $25.00 Beyond Games: Systems Software for Your 6502 Personal Computer Creating programs for the Apple, Atari, Challenger and PET com- puters by Kenneth Skier At last, a complete program- ming guidebook. A self- contained course in struc- tured programming and top- down design, this book presents a powerful set of tools for building an extended monitor, disassembler, hexa- decimal dump routine and text editor programs. ISBN 0-07-057860-5 440 pages; softcover 14.95 Name Title Price Quantity Amount Address City State Zip Check Enclosed Amount Bill Visa/Master Card Number m Expiration Date BYTE Books 70 Main Street Peterborough, N.H. 03458 Circle 64 on inquiry card. Add 75* per book to cover shipping costs: ORDER TOLL FREE 800/258-5420 Total B4 Circle 262 on inquiry card. PRINTERS C. ITOH MODEL 8510 or ADS 8001 PRINT FEATURES Characters: 8 sizes, 5 different al- phabets, upper/lower case descen- ders. Print Mode: 9xN, exceptional qual- ity combined with proportional spacing. Graphics: 144x144 dots/in. and block graphics. Print Head: 9 pins, heavy duty designed with air-cooled fans. Number of Columns: 136 max Print Speed: 120 CPS. Print Direction: Bidirectional logic seeking. Throughput: From 44 to 52 in./min. Line Spacing: Variable to 1/144 in. Print Width: 8 in max. Form: Folded/Sheet. Form Feed: Tractor and friction, bidirectional. Width: 4.5 in. to 10 in. Number of Copies: Original plus 3. PRICE Parallel Interface $550.00 RS232-C Interface 650.00 Apple II Interface 632.00 EPSON MX-80 $449.00 MX-80F/T... 550.00 MX-100 750.00 INTERFACE Available for 8510/Epson with Apple/ Atari/I BM/Osborne/PET/TRS-80. SOFTWARE MICROPRO CP/M Version List Price Our Price WordStar $495.00 $297.00 MailMerge 150.00 90.00 SpellStar 250.00 150.00 DataStar 360.00 210.00 SuperSort I 250.00 150.00 SuperSort II 200.00 120.00 WordMaster 150.00 90.00 CalcStar 295.00 177.00 Apple Version List Price Our Price WordStar $375.00 $225.00 MailMerge 125.00 75.00 SpellStar 200.00 120.00 DataStar 295.00 177.00 SuperSort I 200.00 120.00 SYSTEM PLUS Accounting Plus — CP/M Version. Apple Accounting Plus. MDT MICRO DATA TEK A Division of International Antex, Inc. 2630 California Street Mountain View, CA 94040 (415) 941-7914 TWX 910-373-8500 "INTER AX PTVY" APPLE™ EXPANSION BOARDS PROMETHEUS • MEM-1: Memory expansion mod- ule with quality 16K RAM. Fully buffered. Compatible with Micro- soft Softcard™ CP/M T " and all Apple software. List Price Our Price $169.00 $110.00 • VERSAcard™; Serial/Parallel In- terfaces, Quartz Clock/Calendar; BSR Control. List Price Our Price $249.00 $199.00 ANTEX DATA SYS • ADS PRT-1: Parallel interface card allows you to interface your Apple computer to any printer that has Centronics compatible interface. List Price Our Price $120.00 $60.00 ADVANCE LOGIC SYS • SMARTERM™: 80 column card. Expand your Apple to a full 80 col- umns with the software com- mands. Automatic 80 to 40 and 40 to 80 column switching. Fully compatible with Apple. Pas- cal and CP/M software. Lowest power consumption of all presently available 80 column cards on the market. 9 extra characters included that are not provided on the Apple keyboard: Back Slash, Underline. Accent, Left/Right Brace, Logical OR, Tide, Delete, Bracket, Carrot. List Price Our Price $360.00 $288.00 • Z-CARD: Z-80 CPU with CP/M software. List Price $269.00 Our Price $220.00 VIDEX • Videoterm: 80 column display board. Expand your Apple to a full 80 columns with the software commands. List Price Our Price $345.00 $270.00 • Soft Video Switch. List Price Our Price $35.00 $30.00 ORANGE MICRO • Grappler List Price Our Price $165.00 $140.00 PLOTTERS HOUSTON INSTRUMENT HIPLOT™ List Price Our Price DMP-3 $1085.00 $ 922.00 DMP-4 1385.00 1177.00 DMP-5 1485.00 1262.00 DMP-7 1985.00 1687.00 DMP-6 1685.00 1432.00 DMP-8 2185.00 1857.00 PEN EXCHANGE KIT DMP-442 6 PEN $356.00 DMP-593 8 PEN 456.00 Phone orders accepted. Payment: a Check enclosed □ Master Charge □ Visa n C.O.D. California residents, please add 6% sales tax. All unit prices are fob. Mountain View, California. Technical Forum. 1. ( ) Well, go to— there were no more compari- son,.. Troilus and Cressida, Li 2. ( ) I'll do and I'll do, and I'll do. Macbeth, I, iii 3. ( ) The search so slow! Cymbeline, I, H 4. ( ) A block moved with none... Much Ado About Nothing, III, i 5. ( ) With character too gross... Measure for Measure, I, ii 6. ( ) Your memory is bad.... Loves Labours Lost, IV, i 7. ( ) I have lost com- mand.... Antony and Cleopatra, III, ii 8. ( ) On what condi- tion stands it and wherein...? Richard II, II, iii 9. ( ) ...corrupt cur- rent of the world... Hamlet, III, iii d. g- Well, GO TO; there were no more compari- sons. Oh, I see — the EQUAL flag is set. What do you think of that function we're tracing on the screen? It's not respond- ing when you key in binary. Let's see— it's two NAND's make an OR, and two NOR's make an AND— or is it? I want to design a board that uses nothing but NAND's and NOR's Check where we've halted and what the stack has in it. Make sure the 4 MHz pulse is getting through. It filled the area reserved for in- put with zeros. 364 April 1982 © BYTE Publications Inc Boy, is this costing you. It's really quite basic: time is money. And BASIC takes a lot more time and costs a lot more money than it should every time you write a new business software package. Especially when you could speed things up with dBASE II. dBASE II is a complete applications development package. Users tell us they've cut the amount of code they write by up to 80% with dBASE II. Because dBASE II is the high performance relational database management system for micros. Database and file handling operations are done automatically, so you don't get involved with sets, lists, pointers, or even opening and closing of files. Instead, you write your code in concepts. And solve your customers' problems faster and for a lot less than with BASIC (or FORTRAN, COBOL or PL/I). dBASE II uses English-like commands. dBASE II uses a structured language to put you in full control of your data handling operations. It has screen handling facilities for setting up input and output forms. It has a built-in query facility, including multi- key and sub-field searches, so you can DISPLAY some or all of the data for any conditions you want to apply. You can UPDATE, MODIFY and REPLACE entire databases or individual characters. CREATE new databases in minutes, or JOIN data- bases that already exist. APPEND new data almost instantly, whether the file has 10 records or tens of thousands. SORT the data on as many keys as you want. Or INDEX it instead, then FIND whatever you're looking for in seconds, even using floppies. Organize months worth of data in minutes with the built-in REPORT. Or control every row and column on your CRT and your printer, to format input and output exactly the way you want it. You can do automatic calculations on fields, records and entire databases with a few keystrokes, with accuracy to 10 places. Change your data or your entire database structure without re-entering all your data. And after you're finished, you can protect all that elegant code with our run- time compiler. Expand your clientbase with dBASE II. With dBASE II, you'll write programs a lot faster and a lot more efficiently. You'll be able to write more programs for more clients. Even take on the smaller jobs that were out of the economic question before. Those nice little foot-in- the- data- base assignments that grow into bigger and better bottom lines. Your competitors know of this offer. The price of dBASE II is $700 but you can try it free for 30 days. Call for our Dealer Plan and OEM run-time package prices, then take us up on our money-back guarantee. Send us your check and we'll send you a copy of dBASE II that you can exercise on your CP/M® system any way you want for 30 days. Then send dBASE II back and we'll return all of your money no questions asked. During that 30 days, you can find out exactly how much dBASE II can save you, and how much more it lets you do. But it's only fair to warn you: business programmers don't go back to BASIC's. Ashton-Tate, 9929 Jefferson, Los Angeles, CA 90230. (213) 204-5570. Ashton-Tate ©AshtonTate 1981 KCP/M is a registered trademark of Digital Research. Circle 41 on inquiry card. BYTE April 1982 365 Technical Forum, 10. ( )Lead off this ground, and let's make fur- ther.... The Tempest, I, ii 11. ( ') Against this coming end thou shoulds't prepare. Sonnet, XIII 12. ( )Jump after the inquiry on your own peril.... Cymbeline, V, iv 13. ( )Four negatives make two af- firmatives.... Twelfth Night, V, i m. We're coming up with persis- tent errors dur- ing MEMCHK. Even hitting "RESET" doesn't get us out of this loop! You'll be in trouble if you follow the COMPARE with a GO TO. OK, right here we get a read- ing of zero volts. Let's see where this line ends up. WARNING! Electric Power Pollution. Spikes & Lightning HAZARDOUS to MICROCOMPUTERS!! 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Natick. Mass. 01760 Technical & Non-800: 161 7-655- 1532 14. ( ) Assay the power you have.... Measure for Measure, I, iv 15. ( )Dost thou like the plot? The Tempest, H i 16. ( )I would by contraries ex- ecute all things.... The Tempest, II, i 17. ( )Go, clear thy crystals.... Henry V, II, 3 18. ( )Thou art too base to be ac- knowledged.... The Winters Tale, IV, iv 19. ( )That action, hence borne out may waste the memory of former days.... II Henry IV, IV, v 20. ( )Now I perceive that she hath made compare.... A Midsummer Night's Dream, III, ii See answers on page 374.1 n. ...We get all sorts of garbage on the 115 V AC line when- ever the dryer or refrigerator goes on. o. It'll take all day to find a match. ...if you do that, you'll erase your backup files. q. Why don't you scope the out- put of the 7805? r. You need to sum all the variables as you go along, so that you can get the final totals easily. s. We need finer resolution than we can get with a 5 by 7 dot matrix . I'll take care of those iterations in nested loops, in nested loops. 366 April 1982 © BYTE Publications Inc Circle 168 on inquiry card. STOP SOFTWARE FAILURES Using a micro in a product sounds easy... One piece of software can make the difference between success and failure. What do you do when the software doesn't work? Over the years, we have seen many good products fail, either before or after they reached the market, because the microprocessor software did not do its job. WHAT WENT WRONG? Many of the failures occurred because the people programming the micro did not know how to organize a large control program. Those responsible for the pro- duct implementation were wizards at hardware design and had easily coded small micro control programs before. But the programming techniques that worked for less than 2K bytes of code simply fell apart as the program grew beyond 4K bytes. Unfortunately, the loops and tests and flags that work so well for a small pro- gram get out of control very rapidly as the program grows. Pretty soon, some of the things the program must do are not being done fast enough. The code gets too complicated, difficult to modify and unreliable. The result: another software failure! Fortunately, these problems can be avoided by using a program manager. You can divideyourcomplex control pro- gram into a number of separate, more manageable programs, called tasks, each designed to do one job. For exam- ple, a Keyboard Task might handle user input; a Printer Task might generate re- ports. Each task can be written and tested separately and then combined to form a reliable, finished system. The program manager, called a multi- tasking executive, supervises the orderly execution of these tasks, assuring that the most important jobs always getdone first. Tasks appearto be executing simul- taneously. It's almost like having a separ- ate CPU for each task! That is why professional softwaredes- igners are now turning to AMX as the starting point for their product andjsys- tem designs. They know that AM>f will shield them from the difficulties of mana- ging the micro, freeing them to concen- trate on their application. AMX is our multitasking executive for the 8080, 8085, Z80 and 6809 proces- sors. We're rather proud of it. We made AMX compact, very fast, and ROMable to meet our own application needs. Even though the AMX nucleus is less than 1400 bytes in size, it features multiple task priorities, intertask message pas- sing with priority queuing, external event synchronization, and interval timing: with 32-bit precision. Each feature is clearly explained in the AMX Reference Manual. RELIABILITY BUILT IN We don't know anyone who can write an executive without errors, so we thoroughly tested AMX in real applica- tions before ever offering it as a product. That is why not one system malfunction has ever been attributed to AMX. That kind of reliability just isn't an accident. HARDWARE INDEPENDENCE AMX does not require a particular hardware configuration. Of course, it does need a microprocessor, but even there we offer you a choice. You control your environment. You pick the I/O method. You decide the most optimum interrupt service technique for your sys- tem. AMX will support your choice. High level language interface modules are available separately to allow AMX to be used with most popular program- ming languages including PASCAL, C, PL/M and FORTRAN. Of course, you can also code in assembly language if required. Users of the CP/M and FLEX Opera- ting Systems can utilize our AMX inter- face modules to access information on diskette in realtime. COMPLETE DOCUMENTATION AMX can be judged by the quality of our documentation. The positive re- sponse from our users has exceeded our expectations. Our manuals are es- pecially valuable to those just being introduced to real-time multitasking. More experienced users will appreciate the fact that we deliver AMX source on diskette to permit AMX to be moved to the software development system of your choice. HOW TO ORDER A specification sheet and price list are available, free. Your check or money order for $75 will purchase the AMX Ref- erence Manual for immediate evaluation (specify 8080, 8085,Z80or6809 proces- sor). Add $25 for postage and handling outside USA and Canada. The standard AMX Multitasking Executive package, including source code, is available for $800 after signing our liberal license agreement. AMX is the choice of professionals the world over. Make it yours, today. J It KADAK Products Ltd. IF 1847 West Broadway Avenue Vancouver, B.C., Canada V6J 1Y5 Telephone (604) 734-2796 Telex 04-55670 CP/M is a trademark of Digital Research Corp.; FLEX is a trademark of Technical Systems Consultants, Inc.; Z80 is a 1 trademark of Zilog Corp. Circle 228 on inquiry card. Go with McGraw-Hill's _ . M TAKE ANY 3 BOOKS &-fi FOR ONLY $1«o EACH ■■nil i. .•*.!. when you join the COMPUTER PROFESSIONALS' BOOK CLUB (vaiuesupto $75.00) 6§oa SOFTWARE DiSIGN THE PASCAL HANDBOOK. By Jacques Tiberghien. 471 pp. A sin- gle reference manual that tames this unruly language. Every feature of Pascal isexplained in a brilliantly organized format that covers the major Pascal dialects, including Jensen and Wirth's original defini- tion, with the CDC implementation ... the proposed ISO Standard . . , UCSD Pascal . . . Pascal 1000 (HP1000) . . . OMSI Pascal-1 ... and Pascal/Z. 582365-9B $35.00 (Counts as 2 of your 3 books) MICROPROCESSOR APPLICATIONS MANUAL. By Motorola Semicon- ductor Products, Inc. 720 pp., il- lus., 8V2 x 11 format. With nuts- and-bolts practicality, this manual by the Motorola people (who should know) gives you detailed applica- tions information on micro- processors. Assumes no prior knowledge on your part about MPUs. 435/278B $42.50 (Counts as 2 of your 3 books! charts. The key purpose of the book is to provide both senior manage- ment and DP practitioners with a methodology for identifying and quantifying issues of capacity and demand within the data center without becoming entrapped by language problems 582317-9 $24.95 >< J C* ENCYCLOPEDIA OF COMPUTER SCIENCE. Edited by Anthony Ralston and C. L. Meek. 1,500 pp., 60 illus., 100 charts, 7 x 10 format. This first and only in-depth coverage of the entire field of computer science in a single volume is comprehensive and completely up to date. 769/01XA $60.00 (counts as 3 of your 3 books) By Steve Ciarcia. 330 pp., dia- grams, softbound. Written for peo- ple who don't need an introductory electronics handbook. Its admira- bly achieved objective is to present a practical, step-by-step analysis of digital computer architecture and the construction details for a complete and functional micro- computer. 109/621 $15.95 DATA STRUCTURES USING PAS- CAL. By Aaron M. Tenenbaum and Moshe J. Augenstein. 544 pp., il- lus. With its emphasis on struc- tured design and programming techniques, this definitive work takes you on a trailblazing journey through Pascal. Separate chapters are devoted to the stack, recursion, queues and lists, Pascal list pro- cessing, trees, graphs and their applications. 582230-X $23.95 HOW TO BUILD YOUR OWN WORK- ING MICROCOMPUTER. By Charles K. Adams. 308 pp., 214 illus. and tables. Everything you need to know to build your own microcomputer with a handful of chips! The author takes you through the hardware . . . assembly and running of the sys- tem . . . and details the instruction set and mechanics of program- ming. 582267-9 $16.95 APPLE PASCAL: A Hands-On-Ap- proach. By Arthur Luehrmann & Herbert Peckham. 426 pp., spiral- bound. Finally, a how-to-use- PASCAL book for Apple computer users that makes a complex lan- guage as easy as (forgive us!) applesauce. Takes you from "total ignorance" all the way up to very impressive competence in the use of that rather complex language, PASCAL. 491/712 $14.95 MICROPROCESSORS/MICROCOM- PUTERS/SYSTEM DESIGN. By Texas Instruments Learning Center and the Engineering Staff of Texas Instruments, Inc. 634 pp., illus., outsized 7Va x IOVa format. The book takes you through the devel- opment of memory-to-memory ar- chitecture, shows you the compo- nents, and details programming methods and techniques. 637/58XB $26.95 (Counts as 2 of your 3 books) minicomputer SYSTEMS: Or- ganization, Programming, and Applications. By Richard H. Eck- house, Jr. and L. Robert Morris. 2nd Ed., 491 pp., illus. Updated, revised, and expanded, this is a book for every systems program- mer, systems designer, computer scientist, and application special- ist who wants to know more about microcomputer hardware, software, and design. 787/026 $21.95 AUTOMATIC DATA PROCESSING HANDBOOK. Edited by The Diebold Group. 976 pp., 269 illus. Written by a staff of internationally recog- nized authorities on ADP, this com- prehensive handbook explains sys- tems, programming and the lan- guages, communications pro- cesses, and the design and instal- lation of today's computers. 168/075B $49.95 (Counts as 2 of your 3 books; SOFTWARE DEBUGGING FOR MI- CROCOMPUTERS. By Robert C Bruce. 351 pp., illus. Takes you through the fundamental methods for finding errors, glitches, and faults in programs . . . goes on to techniques for tracking down and exterminating program bugs . . . then combines these techniques into a complete debugging plan. 582075-7 $18.95 EXPERIENCE! **"&» THE DEVIL'S DP DICTIONARY. By Stan Kelley-Bootle. 160 pp., softbound. This devilishly clever lit- tle book isguaranteed tofill anyone who has ever slaved over a hot ter- minal with savage delight. Some 500 computer words and terms are misdef ined, from abacus to your pro- gram. 340/226 $7.50 MICROCOMPUTER INTERFACING. By Bruce Artwick. 352 pp., 117 il- lus. In this up-to-date, complete design guide you'll find the de- tailed descriptions and explana- tions necessary to enable you to select, build, and interface micro- computer systems to virtually all applications. Advanced interface devices and methods are thor- oughly examined and illustrated. 789/436 $24.95 personal COMPUTING: Hard- ware and Software Basics. Elec tronics Book Series. 224 pp., 175 illus., 8V2 x 11 format. Gives you comprehensive guidance to the present state of the art in personal computers — an overall survey of the technology and methods avail- able to perform various tasks, facts about the work others are doing — and just how they are doing it. 191/514 $24.50 PROGRAMMING AND INTERFAC- ING THE 6502-with Experi- ments. By Marvin L. De Jong. 414 pp., heavily ///us., softbound. This guide not only teaches you all you must know about programming and interfacing the 6502, but it also carries you to a high level of under- standing and proficiency quickly and painlessly. 582080-3 $15.95 Z80 USERS MANUAL. By Joseph Carr. 326 pp., with diagrams, charts and tables. Takes you through every opportunity the ZAP can offer. It covers Z80 pin defini- tions, CPU control signals, support ships, interfacing peripherals, and much more. It also includes a 177- page Z80 instruction set so you can study the instructions on a one- by-one basis. 582336-5 $18.95 ELECTRONIC GAMES: Design, programming, and Trou- bleshooting. By w. H Buchsbaum and R. Mauro. 335 pp., 338 illus. Information you need to design, program, and trou- bleshoot electronic games is right here in this widely popular hands- on guide. 087/2108 $26.95 (Counts as 2 of your 3 books) PROGRAMMING LANGUAGES. By Allen B. Tucker, Jr. 439 pp., illus. Gives you not only the principles of design but the applications of six major programming languages. Shows you their strengths and weaknesses in solving various rep- resentative "benchmark" prob- lems. 654/158B $28.50 (Counts as 2 of your 3 books) BIT-SLICE MICROPROCESSOR DE- SIGN. By John Mick and Jim Brick. 398 pp. All in one place — the cru- cial information you've been need- ing about the 2900 family of bit- slice microprocessor components. This remarkable "first" designs right before your eyes not just one but two complete 16-bit machines! 417/814 $24.00 Be sure to consider these important titles as well! 6502 SOFTWARE DESIGN. By L J. Scanlon 582138-9 $10.50 THE GIANT HANDBOOK OF COM- PUTER PROJECTS. By the Editors of 73 Magazine 582012-9 $15.95 SYNTAX OF PROGRAMMING LAN- GUAGES: Theory and Practice. By R. C. Backhouse 582064-1 B $25.95 (Counts as 2 of your 3 books) STRUCTURED PROGRAMMING: Theory and Practice. By R.C. Linger, H.D. Mills, & B.I. Witt 788/537B $22.95 (Counts as 2 of your 3 books) THE BYTE BOOK OF PASCAL. Edited by B. W. Liffick 789/6738 $25.00 (Counts as 2 of your 3 books) THE 2 80 HANDBOOK. 784/914 MICROCOMPUTER By W. Barden, Jr. $8.95 COMPILER DESIGN AND CON- STRUCTION. By A. Pyster 582026-9 $24.50 COMPUTER PERIPHERALS FOR MINICOMPUTERS, MICROPRO CESORS AND PERSONAL COMPUT- ERS. By L.C, Hohenstein 294/518 $19.50 16BIT MICROPROCESSOR AR- CHITECTURE. By T Dollhoff 582003 X $24.95 PRINCIPLES OF INTERACTIVE COMPUTER GRAPHICS. By W. M. Newman & R. Sproull 463/387B $28.95 (Counts as 2 of your 3 books) *If you join now for a trial period and agree to purchase three more books — at handsome discounts — during your first year of membership. (Publishers' prices shown) MAIL THIS COUPON TODAY ■ Why YOU should join now! ■ BEST AND NEWEST BOOKS IN YOUR FIELD -Books are selected from a wide range of publishers by expert editors and consultants to give you continuing access to the best and latest books in your field. ■ BIG SAVINGS — Build your library and save money too! Savings rang- ing up to 30% or more off publishers' list prices — usually 20% to 25%. BONUS BOOKS — You will immediately begin to participate in our Bonus Book Plan that allows you savings of bet ween 70 % — 80 % off the publishers' prices of many professional and general interest books! ■ CONVENIENCE — 12-14 times a year (about once every 3-4 weeks) you receive the Club Bulletin FREE. It fully describes the Main Selection and alternate selections. A dated Reply Card is included. If you want the Main Selection, you simply do nothing — it will be shipped automatically If you want an alternate selection — or no book at all — you simply indicate it on the Reply Card and return it by the date specified. You will have at least 10 days to decide. If, because of late delivery of the Bulletin you receive a Main Selection you do not want, you may return it for credit at the Club's expense. As a Club Member you agree only to the purchase of 3 books during your first year of membership. Membership may be discontinued, by either you or the Club at any time after you have purchased the 3 additional books. Other McGraw-Hill Book Clubs: Accountants* and Controllers' Book Club • Architects' Book Club • Chemical Engineers' Book Club • Civil Engineers' Book Club • Electronics and Control Engineers' Book Club • Mechanical Engineers' Book Club For more information, write to: McGraw-Hill Book Clubs 1221 Avenue of the Americas, 26th fL, New York, NY 10020 McGraw-Hill Book Clubs Computer Professionals' Book Club P.O. Box 582, Hightstown. New Jersey 08520 Please enroll me as a member and send me either the ENCYCLO- PEDIA OF COMPUTER SCIENCE, billing me only $3.00, or any three other books, billing me only $1.00 each, plus local tax, shipping and handling. I agree to purchase a minimum of three additional books during my first year of membership as outlined under the Club plan described in this ad. A shipping and han- dling charge is added to all shipments. □ □ Check here if you want ENCYCLOPEDIA OF COMPUTER SCIENCE (769/01X). Check here if you prefer three other volumes, and indicate below by number the books you want. A few expensive books (noted in the description) count as more than one choice. Name - Address/Apt. City/State/Zip Corporate Affiliation ___„ . This order subject to acceptance by McGraw-Hill. All prices sub- ject to change without notice. Offer good only to new members. Orders from outside the U.S. cannot be accepted. P39552 Announcing the new quick and easy way to write custom business applications in hours instead of weeks. At last, you can get a microcomputer business application development system that is designed for one purpose only . . . fast production of bug-free professional-looking custom business applications. "Thinks" the Way Business Thinks Quic-N-Easi is the revolutionary screen- format-oriented application development system that thinks in terms of transactions, records and fields. The same way business thinks. Quic-N-Easi expects an application to include custom formatted key entry. It lets you set up the character, field, and record validity checks business wants by merely filling in the blanks. It automatically signals in real time when errors occur and "explains" what is wrong in plain English messages you select for each custom application. Much Faster than BASIC Quic-N-Easi programming is much faster than BASIC because the standard busi- ness applications (key input, file handling, and output reporting) are handled via pre-programmed parameter driverLSub- routines. To produce finished professional looking custom business programs, you merely: Draw the business formats directly on the CRT in minutes. r^l Fill in the blanks for field attributes, '-— ^ validations, tables, etc. r^I] Invoke the Quic-N-Easi interpreter L— J to check fields against tables, check limits, access data files, and perform business calculations, etc. H r»J Optionally define file and output L— J formats right on the screen. Pays for Itself in a Week By eliminating the coding drudgery of writing screen, field, file, and format programs in BASIC, programmers are free to concentrate on the unique business aspects of each custom application. No professional programmer can afford to develop one more business application without Quic-N-Easi. The savings are so significant with Quic-N-Easi, it can actually pay for itself in only one week. Gives You Much More than a Screen Builder . . . the Only Complete Business Development System for Microcomputers Quic-N-Easi handles the entire application development job from key entry to final output. You get everything you need, including detailed documentation to begin writing professional programs the first day You get . . . A singularly capable Quic-N-Easi screen builder A comprehensive parameter driven Quic-N-Easi content editor A full Quic-N-Easi interpreter language A complete Quic-N-Easi file management system with Index Sequential, Random, and Sequential File Access Method A complete Quic-N-Easi print format handler A detailed Quic-N-Easi reference manual >. H ["ill A Quic-N-Easi self-teaching guide fill A Quic-N-Easi quick reference card H.1 An interface to other program files ORDER NOW— Don't Waste One More Day Coding BASIC Your time is too valuable to waste hours on end writing BASIC code. The first week you use Quic-N-Easi, your finished business programs will look better, run better, and return more dollars to you. Don't delay. Order Quick-N-Easi today. Phone... 215 968-0689 quid n ■ sasi STANDARD MICROSYSTEMS INC. 136 GRANITE HILL COURT. LANGHORNE. PA 19047 Pricing Information ■ Complete Quic-N-Easi system $395 ■ Manual only $60 ■ Visa and Mastercard accepted ■ Dealer Inquiries Invited Minimum System Requirements Z80 • 48K • Floppy Disc • CP/M (except TRS80 Mod III) Disk Formats 8" Single Density • VECTOR GRAPHICS • MICROPOLIS Mod 2 • TRS80 Mod II • TRS80 Mod III* APPLE • OSBORNE • INTERTEC • ZENITH Apple, CP/M, Intertec, Micropenis, and TRS80 are trademarks of Apple Computer. Digital Research, Intertec Data Systems, Micropolis Corp., and Tandy Corp. TM 370 BYTE April 1982 Circle 381 on inquiry card. Software Review Selector IV by Micro-Ap An Information-Management Program Jack L. Abbott 8525 North 104th Ave. Peoria, AZ 85345 Selector, nationally advertised as an information- management program, was developed by Micro-Ap of San Ramon, California. This is an overview of Selector's capabilities and limitations. You should look at the pro- gram with regard to your particular application before deciding whether to buy it. For those of you who may be unfamiliar with database or data-management programs, here is a brief description of what they do. They accept data in a format that you establish, sort the data in the order that you wish, and ex- cerpt, summarize, and mathematically manipulate the data according to your instruction. They then present the data in a report format of your design. Potential uses for database programs are limited only by the user's imagina- tion: examples include programs for inventory, form generation, mailing lists, appointment calendars, library At a Glance Name Selector IV Type Database management program Manufacturer Micro-Ap 9807 Davona Dr. San Ramon, CA 94583 (415) 828-6697 Price $295 Format 5- or 8-inch floppy disk, or hard disk (running under CP/M 2.2) Language CBASIC, version 2.05/35 or later Computer System System with 52 K (or more) bytes of RAM running CP/M 1 4x or 2. xx operating system, with 24-line by 80-column cursor- addressable display terminal and a printer Documentatfon Preliminary version, 210 pages in three-ring binder Audience Everyone who has a microcomputer document lists, check making, and check-book listing. Selector IV, the current version of this program, suc- ceeds version III-C2. Version IV represents a quantum leap forward, especially in its usefulness to someone who is not a skilled programmer. Selector IV lists at $295 and Selector III at $195. My comments in this article address version IV, but for those who have been using version III, Selector IV provides a program for convenient conver- sion of your data files to a suitable format for version IV. Selector IV requires a CP/M-compatible (version 1.4, 2.0, or 2.2) operating system, CBASIC version 2.05/35 or later, and a 24-line by 80-column (or larger) video- display capability with absolute cursor addressing and erase-screen functions. Micro-Ap supplies two disks, one with the Selector IV source code and one with the com- piled programs. No compilation is necessary, and the program as received runs under CBASIC2. Micro-Ap recommends using a printer: I would say one is essential. You can adapt Selector to your terminal and computer by menu selection. Micro-Ap will provide Selector in any microcomputer disk format that is in general use, but I had to wait about six weeks to get a disk formatted for Micropolis Mod II (Vector Graphic) drives. Some of the printed descriptions furnished by Micro-Ap state that Selector IV will run in "48 K or more of user memory space" (i.e., 48 K bytes of random-access read/ write memory), Micro-Ap interprets this statement to mean that additional memory is required for CP/M, etc., which means that a user needs at least 52 K, and opera- tion is better with 56 or 64 K. The program documentation is a preliminary version, but this is not a serious limitation. All the required infor- mation is present, although a large portion is included in addenda and is not listed in the index. The program ex- planations in the documentation are very good — the Micro-Ap writer does not presuppose extensive engineer- ing or programming experience. April 1982 © BYTE Publications Inc 371 Running Selector To initialize the program, tell Selector what kind of equipment you are using, as well as company or personal information that you want the program to use in report headings. Next, define the format of the information you wish to enter. The written instructions are explicit and are supplemented by detailed prompts on the display screen. Configuration of the data "fields" (individual data items) making up one data record (a collection of related items) is simple, and there can be up to eighty fields in one record. These individual fields contain all the infor- mation about one subject. In a mailing-list program the subject would be one person or business; in an inventory program the subject would be one product or compo- nent. Record length cannot exceed 255 characters. All related records are stored in one file. There is no reasonable data-table format that Selector cannot generate. After you establish the format of the data to be input, the program presents the format whenever requested and assists in making certain that no mistakes are made in entering the data. On completion of a data -entry session, Selector automatically merges the new data into the exist- ing database and then asks for further instructions. Once the input format has been defined and the data entered, tell Selector which records you want to select for printing or display by specifying select or sort re- quirements, called "definitions." Upon request, the pro- gram executes these "definitions" by going through the database and picking and sorting the appropriate records. The final step is to establish how you want the selected data to be presented. Selector provides two ways: "page reports" and "line reports." Selector can send these reports to either the terminal or the printer. A total of as many as 80 different fields from six different files may be presented. You can specify mathematical operations ( + ,""///*) and logical operations (equals, greater than, less than, etc.) on or between data fields. The data fields can be summed. The page-report function, used to generate forms like invoices or purchase orders which require that data be placed on a specific place on a page, should be one of the most valuable features. However, defining the para- meters for this function and troubleshooting its operation take so much time that much of the potential is wasted. Using a series of single-letter and number codes, you must tell the program exactly where each data field is to be placed on the form. Learning the codes is like learning another programming language and it takes a long time to get the report right. The line-report function is easy to define. It consists of as many data fields as you choose, taken from the records you select, placed one after another on as many lines as required. The line-report function includes mailing-list processing. The mailing list label-printing subprogram is outstanding. It is easy to define, will print from one to Give Your TRS-80* a Tremendous Boost with RACET computes Software RACET computes Utility Software makes the TRS faster, more efficient, and easier to use. Our programming aids improve your productivity. Our reputation is for products that are professional in design and work as advertised!!! FIELD PROVEN HARD DISK DRIVES AND OPERATING SYSTEM Now you can use RACET's Hard/Soft Disk Operating System (HSDS) with the ARM Winchester Disk Drive on the Model it. This cost effective combination provides 15 Megabytes per drive including ECC Error Correction Code and an advanced sequencer to further ensure data integrity. An incremental backup to floppy is provided so that only those sectors that were changed from the last backup are saved. A full monthly service contract is available at $30 per month per drive. The HSDS Software has more than One Year's FIELD Experience. The latest HSDS version adds several enhancements including maintenance of system files on the hard drive, files as large as the disk, the ability to segment the disk as logical drives, definable directory size, and many utilities including bulk copies between floppy and hard drives, multiple purge, Superzap, and Directory Catalog System. Full program compatibility with TftSDOS 2.0a is maintained. Mixed floppy and hard drive operation is supported. HSDS is available for the Cameo, Cynthia Bull, Corvus, Data Peripherals, and Santa Clara Systems hard disk systems as well as the ARM Winchester Drive. ARM 15 Megabyte Drive Subsystem $3895. HSDS Software $400. Cameo 5/5 Cartridge Drive $5995. Cynthia Bull 10/10 Drive $7995 new product • Model II Fast Backup Utility • $75 5 to 10 times faster backups!!! Full disk backup (including verify) 55 seconds!!! on two drive system — 2:15 on single drive system. In business, time is money, and one BACKUP is worth 1000 tears!! NEW PRODUCT * INTEGRATED BUSINESS SYSTEM • ISAM File Structure — Multi-Company Capability. Modular structure. Each module includes complete user documentation which guides the user through installation and allows "practice" using a sample data base. When ready, the user simply names his data base and begins The Integrated Business System program set includes General Ledger, Accounts Receivable, Accounts Payable, Payroll, Inventory, General Journal, Asset Management and more. Business Programs $250/module Mod III, $300/module Mod II, $795 for all four Mod III, $995 for all four Mod II. General Ledger and Accounts Receivable available now. Accounts Payable and Payroll 1 st Quarter 1982. I 1 RACET ■— 1330N.GLASSELL. SI COMPUTES 1 1330 H. GLASSELL SUITE M, ORANGE, CA 92667 CIRCLE READER RFSP0NSE BELOW FOR FREE CATALUG •TRS-80 IS A REGISTERED TRADEMARK OF TANDY CORPUHATlGN CHECK. VISA. M/C. COD. PURCHASE ORDER TELEPHONE ORDERS ACCEPTED (714) 997-4950 GET THE MOST FROM YOUR NEC PC-8001 WITH RACET computes SOFTWARE!! RACET NECD0S $175 RACET NEC00S does more for your PC-8001 than any other DOS. It's faster, more efficient and easier to use. It's loaded with extra features to let you stretch the limits of your system. This advanced operating system works with the ROM N BASIC to give full compatibility with color and other BASIC commands. USER FRIENDLY — Emphasizes Integrity. No MOUNT or REMOVE commands!!! Excellent protection from improper diskette swapping. AGAIN, HELP. FIND and REF commands. File password protection. ADVANCED DESfGN. RACET NECD0S utilizes the computer in the 8031 for most disk I/O functions minimizing memory utilization in the PC-8001. The Dynamic Transient Area $ ;<«>?tA8CQEFG abcd«f«hijklftfto Lower Case Character Generator for the Rev. 7, Apple II or II+ computers. When installed, this Eprom will generate lower case characters to the video screen. Lower case characters set has two dot true descenders. Installation instruction included. Manual includes listing of software for full support and complete instructions for shift key modification. Compatible with LETTER PERFECT. DEALER INQUIRES INVITED LJK ENTERPRISES INC P.O. Box 10827 St. Louis, MO 63129 (314) 846-6124 Trademarks of: Apple Computer — Atari Computer — Epson America — Hayes Microcomputers — Personal Software - Videx - Bit 3 Inc. - M&R Ent. - Advanced Logic Systems — Vista Computers Circle 236 on inquiry card. BYTE April 1982 373 eight labels across, and prints slightly less than 600 labels an hour (using a Dynabyte 8/2 and an Epson MX-80 printer in a two-across format). Unfortunately, this sub- program works effectively only in batch mode (this in more detail later), A Sample Application Listing 1 shows the data-input format of the mailing- list program that I developed to meet my own re- quirements and to learn the program. In the "Type" col- umn "A" is alphanumeric, "N" is numeric, and "K" is for key. The user can designate any field as key. The pro- gram will then have the capability of sorting or selecting data records based upon one or a combination of key fields. In the sample shown, you could select all the records for a state with a given zip code, then select all the people in that state whose last names begin with A, and so on. You could print as many of the individual data fields as you wished, in addition to the key fields, in a given record. My use of field 13 in listing 1 is a good example. I assign "B" for all business entries, "P" for per- sonal entries, and "A" for entries that are both business and personal. When I print a mailing list, I can select and print all the labels for personal entries by selecting "P", all the labels for business entries by selecting "B", and all those that are both business and personal by selecting "A". Based on the records I have selected I can then set up the report to include any other desired fields as well as the Answers to MicroShakespeare Quiz 1-a 6-j 11-r 16-f 2-t 7-k 12-1 17 -h 3-o 8-g 13 -e 18 -d 4-i 9-n 14 -q 19 -p 5-s 10 -m 15 -c 20 -b Number of MicroShakespeare Correct Matches Rating 20 You're making the best of BYTE and Bard. 17 - 19 Software almost ready to burn into ROM. 13 - 16 Something wrong with housekeeping; GO TO ORG. 9-12 Make sure you have the right chips installed. 5-8 Clear memory and start over. 4 or fewer Send for a new processor. ■ key fields, e.g., home address, business address, and city. A limitation of the Selector program is the inability to function in other than a "batch mode." It takes several minutes to bring Selector up and load the program module that inputs data records. You can then enter data records rapidly. When you exit the data-entry function, Selector will automatically merge the new data with the old and reload the operating program and menu. Before you output a report, you must run the select and sort Listing 1: A Selector IV record-definition file. Fields are numbered and named in the first two columns. Key size is the number of characters taken from a key field that actually make up the key. The last column shows the "byte offset" for each field, i.e., the number of bytes into the record counting from the beginning to the first byte in the field. Record definition -file: B: MALIST. DEF as of APR 23, Data -file drive: B Key/Support drive: B Data record length: 218 Key record Length: 19 ## Name Type Data Size Key Size Byte Offset 4 5 6 7 8 9 to 11 12 13 FRSTNAME LASTNAME TITLE CMPNYNAM CMPNYADD HOMEADDR CITY STATE ZIPCODE HOMPHONE BUSPHONE REMARKS BPCODE A AK A AK A A A AK NK A A A AK 25 2G 15 25 25 25 20 5 14 14 10 ID 1 26 46 61 86 111 136 156 158 163 177 191 216 An Improved Selector As this article goes to press, we at BYTE find ourselves once again trying to catch up with an industry that changes faster than we do. The final documentation is now available for Selector IV and the package allows CODASYL-type record-accessing conventions (including one-to-many, many -to-one, and many -to-many record accesses). Micro- Ap has also introduced Selector V, a machine- language database (compiled from BASIC code through Digital Research's CB80 package) that does not require pur- chase of any additional language. According to Bob Good- man of Micro-Ap, Selector V works in the same way as Selector IV, but is SVz to 6 times faster. Added features in- clude the extended record-accessing conventions mentioned above, a removal of the 256-byte record-length restriction of Selector IV, and file and record locking and unlocking capabilities (which can be used when Selector Vis used under the MP/M operating system). Selector V lists at $495. 374 April 1982 © BYTE Publications Inc INTRODUCING f Jal f 5TJaR^ Presenting CalcStar — another standard- *-^** , ^ b * ""Wi setting software product in the WordStar smMI^J I J§t§a[lC CalcStar is Micro Pro s new electronic a^lilfcl IJFWLWBMft A M W s P reac i sheet and financial modeling program — II Ir E jABI a sophisticated, yet easy to use, calculating ^mmm*mmMm£um an< ^ P^ annin g to °^ f° r CP/M®based computers. R J5 1 N t55 ^ e u lti mate electronic spread sheet* m9%0'^mMWmi^mtm CalcStar calculates solutions to complex E^KM^^ IffAHH EDf^lUI n ^nierical problems in business and finance. ■ Im%r %M ImMUi Wl i llwlfl Helps you make budget plans and sales fore- m CPA DP A' casts wit ^ 8 reater speed and accuracy. And Iwl ! ^L IC W 1 Im^rf projects figures into the future to answer the mm ■■ lifAflflfTA ff% "what if questions you face in business. 1 ■fl|t l IWy \PJClr J IgmlC ^ nc ^ CalcStar also has a unique MicroPro UPAIil ■■ advantage: It joins with WordStar to combine pElnpi E spread-sheet and word-processing capabilities in * ■"■ ■•• several powerful ways. CalcStar software eliminates the need to use ledger paper ever again. It turns your video screen into a 'window" on a giant electronic ledger sheet, with up to 600 entries arranged the way you want. Then, by inserting formulas into CalcStar, you create financial models that simulate the future numeri- cally. And predict the outcomes of your business decisions. When you notice what CalcStar can do for your business you 11 wonder how you ever got along without it. (If you're now a WordStar user, you probably already know the feeling.) The MicroPro bonus* Like WordStar, CalcStar is packed with innovative features that make it versatile and easy to use. Features like Automatic Forms Mode, which lets an inexperienced user enter data into a spread sheet quickly and with less chance of error. CalcStar s greatest innovation is its ability to join with WordStar. Which means, for example, you can use WordStar's printing options, like boldface and underlining, to dress up financial documents. And you can insert sections of CalcStar 's spread sheets into your WordStar documents. This kind of flexibility should come as no surprise if you're already familiar with the MicroPro software family— a line of programs designed to work together to multiply your problem-solving power. Visit your MicroPro dealer to find out just how big a difference all our products can make in your business. We predict you'll discover its not just CalcStar or WordStar that's indispensable. It's MicroPro. A glance at CalcStar features Runs on CP/M version 2.0 or above, with 80- column screen, addressable cursor, and at least 48K memory. 56K or more is recommended for fullest utilization. Highly user friendly: Call up full screen of help or use help menu, WordStar-like cursor commands. User's guide shows you the basics. Install from menu OR a WordStar file. Stores formulas and formats along with data, for convenience and less chance of error. Math functions include average, minimum, maximum, logarithms, exponents, and regression analysis. SOFTWARE TH AT MEANS BUSINE SS ' microPfp INTERNATIONAL CORPORATION 1299 Fourth Street, San Rafael, California 94901 (415) 457-8990; Telex: 340-388 CP/ M is a trademark of Digit; Dealer and disttil ."■-.;,.- Wfe **«f»ai» s^crs^r «**** ^kst. Circle 268 on inquiry card. BYTE April 1982 375 Listing 2: A CBASIC program for printing a single label or envelope. The program pulls information about an addressee from the Selector IV database as soon as the user gives enough information to identify a record uniquely. If the user doesn't reference a data file, the program lets the user type an address onto an envelope in the system's printer. >******* R EJW ************************************************ REM PROG RAN TITLE : TYPMAL. B AS REM JACK ABBOTT, PEORIA AZ 6/16/81 REM THIS PROGRAM WILL TYPE ENVELOPES WITH NO OTHER FILE, OTHERWISE REM PUT MALIST DATA ON B DRIVE, AND THEN RUN THIS PROGRAM. REM THIS PRO. TYPES ADDRESSES, ENVELOPES, OR LABELS. INPUT "PUT MALIST.DAT ON B DRIVE THEN PRESS RETURN-" ; LINE DUMB$ 22 T%=0 OPEN "E:MALIST.DAT" AS 1 INPUT "NAME WANTED OR OWN ENVEL. ADDRESS ( OWN) -" ;N$ IF N$="OWN" THEN 150 28 READ #1;LINE MALIST$ T%=T%+1 A%=1 S$=MALIST$ IF MATCH {N$,S$,1)>0 THEN 112 IF END #1 THEN 21 GOTO 28 21 INPUT CLOSE 1 IF M$="Y' GOTO 7 77 112 INPUT "ENV. OR LABEL,E OR L?";F$ INPUT "BUSINESS OR PERSONAL? B OR P";Z$ IF F$=" E" THEN 2 22 INPUT" PHONE# WANTED?Y/N";E$ INPUT "# Of LABELS WANTED?" ;I% G% = 1 IF I%>1 THEN Q%=I% ELSE Q%=1 GOTO 666 150 A%=5 GOTO 222 444 CONSOLE INPUT "MORE?Y/N?";P$ E$="N" CLOSE 1 NAME NOT FOUND, MORE? Y/N";M$ THEN 22 IF P$="Y" THEN 22 GOTO 777 666 LPRINTER C% = 25 FOR B»l TO Q% 670 IF Z$="B" THEN 680 676 B$=LEET$(S$,C%} IF RIGHTS (B$,l)=" " THEN 446 PRINT TAB(G%) , -LEFTS (S$ f C%) ; B " ,-MID$ (S$ , 26 , 20) PRINT TAB(G%) ;MID$ (S$ , 111 ,25) 681 PRINT TAB(G%) ; MID$ (S$ , 136 , 20) PRINT TAB{G%) ; MID$ (S$ , 156 , 2) ;CHR$ ( 32) ; CHR$ ( 32) ;MID$ (S$ , 158 , 5) IF E$="Y" THEN 445 PRINT 677 PRINT NEXT GOTO 44 4 680 PRINT TAB(G%) ; MIDS (S$ , 61 , 25) PRINT TAB{G%) ; MID$ (S$ , 86 ,25) GOTO 681 445 PRINT TAB(G%) ;MID$ (S$ ,163 , 13) GOTO 677 446 C%=C%-1 GOTO 676 222 INPUT "LEGAL OR REGULAR?L OR R";K$ G% = 20 If K$="L" THEN G%=40 INPUT "READY TO PRINT?Y/N" ; D$ IF D$="N" THEN 444 LPRINTER PRINT "JACK L. ABBOTT" PRINT "8525 N. 104TH AVE." PRINT "PEORIA, ARIZ. 85345" PRINT: PRINT: PRINT: PRINT: PRINT: PRINT: PRINT: PRINT: PRINT CONSOLE IF A%>1 THEN 180 GOTO 666 180 INPUT "NAME-FIRST LINE?"; LINE 0$ INPUT "STREET ADDRESS-SECOND LINE?"; LINE J$ INPUT "CITY, STATE, ZIP? LAST LINE";LINE V$ LPRINTER PRINT TAB (G%) ; 0$ : PRINT TAB (G%) ;J$ : PRINT TAB{G%);VS PRINT:PRINT CONSOLE GOTO 444 777 STOP definitions on the updated database. These operations take several minutes. The overhead time is acceptable when you're processing lots of records, but unacceptable when you're processing just a few. This may or may not be a problem, depending on what you're using the pro- gram for. If you want to enter and then recall a record, as in the case of inputting the data for a single invoice or receipt and then printing it, the time overhead is too great. A printer is a necessity because you can print out data, mark changes on the sheet in pencil, and then enter all the changes at once. In the case of mailing-list infor- mation there is no way to pull out and print a single name and address other than to generate a report, and that takes several minutes. One way to save time is to use the program in listing 2. This CBASIC program scans the data files created by Selector, picks out individual addresses, and prints labels or envelopes. The program also types individual en- velopes with your return address and lets you type the addressee, line by line, from the console. Apart from ac- cessing the mailing-list database, the program operates independently of Selector, so it can be compiled separ- ately. You choose functions from a menu and the pro- gram will pick any address record if you enter enough let- ters or numbers to give a unique identity — these iden- tifiers can be first names (as long as there are no duplicates), street numbers, or whatever you decide. A minor annoyance is Selector's use of the terminal alarm, which sounds whenever anything "noteworthy" happens. Unfortunately the designers find many things noteworthy that I do not (including disk transfers, entry of the day's date, improper inputs), and initially I kept wondering what mistakes I had made whenever the alarm went off. A program toggle should be provided to disable this feature. Another confusing factor is a display heading that tells you when a disk operation is going on so you won't attempt any keyboard action. The heading appears most, but not all of the time, so after a while I forgot to look at the disk-select light. Later, when I started poking at the keys, I wondered why nothing was happening during some disk operations. Conclusions The Selector program is written entirely in CBASIC, but the merge and sort functions are fast, so the program as a whole runs rapidly. The program can enter and retrieve many records at a time extremely well, but if you want to switch back and forth between data entry and display, or print in less than several minutes, you will have to modify or supplement program operation. The mailing-list module is excellent, easy to define, and executes quickly. In addition, the program shown in listing 2 allows you to select and print individual addresses. The line-report function is also excellent and easy to use; unfortunately, the page-report function re- quires a great deal of effort and time. I find that a printer, preferably with 132 -column print capability, is essential for most uses. Selector should be purchased with the final documen- tation package, but the program description is clear and well written in the preliminary version, and the program performs exactly as the documentation says it will. Selec- tor has the potential to perform a number of different functions well. If it meets the requirements of your task, it represents a good value when compared to the cost and time of developing custom software. ■ 376 April 1982 © BYTE Publications Inc Double your disk storage capacity simply by switching to Omni's new reversible disk. If you have an Apple, TRS-80, Zenith, North Star or any other single-sided 5V4 W disk drive, you can double disk capacity by simply switching to the Flip/Floppy disk from Omni. It works just like your present disks, except you can flip it over and record on the reverse side. So you can consolidate programs and files that used to require two disks. You can halve your disk requirements. And save money. Each disk comes with some impressive specifica- tions: They're certified error-free at more than twice the error-threshold of your system. Rated for more than 12 million passes without disk-related errors or significant wear. And precision fabricated with such standard features as reinforced hub rings. Call Omni toll-free today. Get premium disks. Twice the capacity. A full money-back guarantee. Unbeatable price. And if you order a ten pack now, a free $5.00 storage case as well. OMNI Omni Resources Corporation 4 Oak Pond Avenue, Millbury, MA 01527 (800) 343-7620 In Mass. (617) 799-0197 Dealer inquiries invited. Software Houses: We also offer duplicating and formatting services. $26.00-Five pack (Equivalent to lO single-sided disks) $5QOO-Ten pack (Equivalent to 20 single-sided disks) Free Protective plastic storage case with each lO pack ordered by 5/1/82 Order toll-free (800) 343-7620. In Mass. (617)7990197 Circle 305 on inquiry card. Send the following Flip/Floppy disks. I understand they have a full 90 day money-back guarantee if I'm not completely satisfied. System & model # Five packs @ $26 OO $ Ten packs @$50.00* S ' includes plastic case Shipping and handling $ 5% sales tax (Mass, only) $ Total $ Check (to Omni Resources) C.O.D. Master Card Visa Card # Exp._ Name . — Address __ — ISO Tel DYNACOMP Quality software for *. ATARI PET/CBM APPLE II Plus OSBORNE-1 ALTAIR**** TRS-80 (Level II)** NORTH STAR*** CP/M Disks/Diskettes See Availability box . ( MBASIC/CBASIC SUPERBRAIN***** CARD GAMES Price: S21. 95 Diskette KIDGE MASTER BRIDGE MASTER is a comprehen- liiion. Bidding features include the Blackwood conven- demand bids and jump-shift responses. After playing a :r opponents. This feature BRIDGE MASTER (North Star only) If you liked DYNACOMP'S BRIDGE 2.0. you will absolutely love sive bridge program designed to provide hours of challenging torn lion, Stayman convention, pre-emptive openings, and recognition specific hand, you may replay the same hand, with the option ol sv, allows you to compare yoer bidding and playing skills lo BRIDGE MASTER, Bonuses for game i awarded as in duplicate bridge. Doubled contracts are scored based upon a computer assigned vulnerability. A score card is displayed at the conclusion of each hand. The score card displays a summary of total hands played, total points scored. number of contracts made and set. and "t bids made BRIDGE MASTER is clearly the best computer bridge program available. DYNACOMP'S previous BRIDGE 1.0 customers may upgrade to BRIDGE MASTER for a nominal charge of $5.00 plus postage and handling (see ordering information bos). BACCARAT (Atari only) Price: $1».9S Cassette /$22. 95 Diskette This is the European card game which is the favorite of the Monte Carlo jet set. Imagine yourself at the gaming table with 007 to your left and Gold finger to your right. Learn and play BACCARAT at your leisure on the Atari, Contains full high resolu- tion color graphics and matching sound. Runs in 16K Requires one joystick. GIN RUMMY (Apple diskette only) This is the best micro computer .mpk-tiu-titaiion ol GIN RUMMY e) HIRES graphics are superb. What else can be said? POKER PARTY (Available for all computers) Price: $17.95 Cassette/$21.95 Diskette POKER PARTY is a draw poker simulation based on the book. POKER, by Oswald Jacoby. This is the most comprehensive version available for microcomputers. The party consists of yourself and six other (computer) players. Each of these players {you will get to know them) has a different personality in the form of a varying propensity to bluff or fold under pressure. Practice with POKER PARTY before going to that expensive game tonight' Apple cassette and diskette versions require a 32 K (or larger) Apple 11 GO FISH (Available for all computers) OO FISH is a classic children's card game. The opponent is small children to easily master. The Apple and Atari versions for children* Price: $14.95 Cassette $18.95 Diskette i friendly computer with user inputs that are simple enough for mploy high resolution graphics for the display of hands. A must BLACKJ AC K < < 1ACH (32K TRS-W only) Price $29.95 Cassette/ $33. 95 DUkette BLACKJACK COACH is both a game and an educational lool. With this program you may quantitatively test standard and special playing and betting methods, including the several card count schemes. You can simply play, play with the compute! as a coach, or statistically test your method under long run automatic play. All the standard player choices are included: in- surance, splitting pairs, double downs and surrender (optional). The computer analyzes the technique and provides detailed summary reports which statistically pinpoint the strengths and weaknesses ol vour plav. Don't risk your money at the tables until you have practiced with BLACKJACK COACH! THOUGHT PROVOKERS MANAGEMENT SIMULATOR (Atari, North Star, OSBORNE and CP/M only) Price: $19.95 Cassette $23.95 Diskette This program is both an excellent teaching tool as well as a stimulating intellectual game. Based upon similar games played at graduate business schools, each player or team controls a company which manufacturers three products. Each player attempts to outperform his competitors by selling selling prices, production volumes, marketing and design expenditures etc. The most successful firm is [he one with the highest stock price when the simulation ends. FLIGHT SIMULATOR (Available for all computers) Price: SI 7. 95 Casselte/$21 .95 Diskette A realistic and extensive mathematical simulation of take-off, flight and landing. The program Mfdom aerodynamic equations and the characteristics of a real airfoil. You can practice instrument approaches and navigation using radials and compass headings. The more advanced flyer can also perform loops, half-rolls and similar acrobatic maneuvers. Although this program does not employ graphics, it is exciting and very addictive. See the software review in COMPUTRONiCS. Runs in I6K Atari. V ALDEZ (Available for all computers) Price: $15.95 Cas»ette/S19.95 Diskette VALDBZ is j computer simulation of supertanker navigaiion in the Prince William Sound/ Valder. Narrows region of Alaska. Included in this simulation is a realistic and extensive 256 x 256 element map. portions of which may be viewed using the ship's alphanumeric radar display The motion of the ship itself is accurately modelled mathematically. The simulation also contains a model for the tidal patterns in the region, as well as other traffic (outgoing tankers and drifting icebergs). Chan your course from the Gulf of Alaska to Valdez Harbor! See the software reviews in BO Software Critique and Personal Com- BACKGAMMON 2.0 (Atari, North Star, OSBORNE and CP/M only) Price: 514.95 Cassette/511 ,95 Diskette This program tests your backgammon skills and will also improve your game. A human can compete against a computer or against another human. The computer can even play against itself. Either ihe human or the computer can double or generate dice rolls. Board positions can be created or saved for replay. BACKGAMMON 2.0 plays in accordance with the official rules of backgammon and is sure to provide many fascinating sessions of backgammon play. CHESS MASTER (North Star and TRS-80 only) Price: $19.95 Cassette/ $23 .95 Diskette This complete and very powerful program provides five levels of play. Il includes castling, en passant captures and the promo- tion of pawns, Additionally, the board may be preset before the start of play, permitting the examination of "book" plays. To maximize execution speed, the program is written in assembly language (by SOFTWARE SPECIALISTS of California). Full graphics are employed in the TRS-80 version, and two widths of alphanumeric display are provided lo accommodate North Star users. See review in onComputing, FOREST FIRE1 (Atari only) Lsing excellent graphics and sound effects, this simulation puts you in the middle of a fore lions lo put out the fire while compensating for changes in wind, weather and terrain. Not result in startling penalties. I ife-like variables are provided to make FOREST FIRE! very suspcnselul and challenging. No two games have the same setting and there are 3 levels of difficult. BLACK HOLE (Apple only) Price: $H.95 C asset te/$l». 95 Diskette This is an exciting graphical simulation of the problems involved in closely observing a black hole with a space probe. The ob- ject is to entet and maintain, for a prescribed time, an orbit close to a small black hole, This is lo be achieved without coming so near the anomaly that the tidal stress destroys the probe. Control of the craft is realistically simulalcd using side jets for rotation and main thrusters for acceleration. This program employs Hi -Res graphics and is educational as well as challenging. SPACE EVACUATION ! (Apple, Atari and TRS-M only) Price: S15.9S Cassette/ 5 19.95 Diskette Can you colonize ihe galaxy and evacuate the Earth before the sun explodes? Your computer becomes the ship's computer as you explore (he universe to relocate millions of people. This simulation is particularly interesting as it combines many of the exciting elements of classic space games with the mystery challenge of ADVENTURE. MONARCH (Atari only) Price: SI 1.95 Cassette/$ 15.95 Diskette MONARCH is a fascinating economic simulation requiring you to survive an B-year term as your nation's leader. You deter- mine the amount of acreage devoted to industrial and a«ru:ut!in-al use, how much food to distribute to the populace and how much should be spem on pollution control. You will find thai all decisions involve a compromise and that it is not easy lo make everyone happy. Runs in I6K Atari Price: $1 l.W Cassette/SIS, 95 Diskette ist bite off part of a cookie, but avoid uk- fully uses the Atari's graphics capability, CHOMPELO (Atari only) CHOMPELO is really two challenging games in one. One is similar to NIM; you n ing the poisoned portion. The other game is the popular hoard game REVERSI. I and is hard to beat This package will run on a 16K system AVAILABILITY DYNACOMP software is supplied with complete documentation containing clear explanations and examples, Unless otherwise specified, aBprOaraaM will run wrhin 16K program memory space (ATARI requires 24K). Except where noted, programs are avail- able on ATARI. PF.T, TRS-80 (Level 11) and Apple (Applesoft) cassette and diskette as well as North Star single density (double density compatible) diskelte. Additionally, most programs can be obtained on standard (IBM 3740 single density.' double density compatible format) 8" CP/M floppy disks for systems running under MBASIC or CBASIC (for example. Altos, Xerox 820 and many others). 5'V CP< M diskettes are available for the North Star and Osborne computer systems. •for muss Sonh Mar disk-based systems. D YSA COMP prrsenily does not "for Aliair systems hmmg Microsoft BASIC. ■■•rW SLPf.HBHAIS interns running under MBASIC or CBASIC (stale 'e registered tradenames and 7 or support Ihe new North Star Advantage. DYNACOMP OFFERS THE FOLLOWING • Widest variety • Guaranteed quality • Fastest delivery • Friendly service • Free catalog • Toll free order phone AND MORE. STARTREK 3.2 (Available for all computers) Price: $1 1.95 C»sselte/S15.95 Diskette This is the classic Starlrek simulation, but with several new features. For example, the Klingons now shoot at the Emerprjse without warning while also attacking starbases in other quadrants. The Klingons also attack with both light and heavy cruisers and move when shot at! The situation is hectic when the Enterprise is besieged by three heavy cruisers and a starbascS.O.S. is received! The Klingons get even! See the software reviews in A.N.A.L.O G., 80 Software Critique and Game Merchandising LIL' MEN FROM MARS (Atari only) Defend yourself! The little men from Mars ai animated graphics (arcade) game which exerc Price: $19.95 Cassette/ $23 .95 Diskette out to get you if you don't get them first. This is a hilarious high resolution s much of the Atari's power. Requires one joystick. SPACE TILT (Apple and Atari only) Use (he game paddles to tilt the plane of the TV screen to ' 'n hole gels smaller and smaller! A built-in timer allows you l< ESCAPE FROM VOLANTIUM (Atari only) Biing the action and excitement of an arcade into your hoi maneuver your space ship around obstacles and laser blast * t just a leg lopped off), a door opens to the outside. Howev, Price: $10.95 Cassette/S14.95 Diskette "a ball into a hole in the screen. Sound simple? Not when the measure your skill against others in this habit-forming action Price: $15.95 Casselte/$I9.95 Diskette f with ESCAPE FROM VOLANTIUM! To escape you must dragon (without being eaten). If he is killed with a direct shoi ihe door does not stay open indefinitely. If you fail to escape in time, Ihe door closes and a new dragon appears. Sometimes you can smash through the door by repeatedly chipping away at it. Other times it is impervious. At the higher levels of play more obstacles and dragons appear, adding to the excitement. Uses high resolution graphics and sound. Runs in I6K. Price: $12.95 Cassette- $16. 95 Diskette quires you to destroy the alien slarships passing IFO invasion; lei five UFO's get by and the game e higher you score! Al PHA FIGHTER will run ALPHA FIGHTER (Atari only) Two excellent graphics and action programs in one! ALPHA FIGHTER through your sector of the galaxy. ALPHA BASE is in the paih of an alici ends. Both games require the joystick and get progressively more difficull on 16K systems. THE RINGS OF THE EMPIRE (Atari only) Price: $14.95 Cassette /$li.95 Diskette The empire has developed a new battle station protected by rotating rings of energy. Each time you blast through Ihe rings and destroy the station, the empire develops a new station wuh more protective rings. This exciting game runs on I6K systems, employs extensive graphics and sound and can be played by one or two players. INTRUDER ALERT (Atari only) Price: S 14. 95 Cassette/ $18. 95 Diskette This is a fast paced graphics game which places you in the middle of the "Dreadstar" having just stolen its plans. The droids have been alerted and are directed 10 destroy you at all costs. You must find and enter your ship to escape with the plans. Five levels Of difficulty are provided. INTRUDER ALERT requires a joystick and will run on I6K systems. ' MIDWAY (Atari only) Price: $14.95 Cassette/$1S.9S Diskelte MIDWAY is an exciting extension of the game of Battleship. It mixes the challenges of strategy and chance. Your opponent can be another human or the computer. Color graphics and sound are both included. Runs in I6K. TRIPLE BLOCKADE (Atari only) Price: S14.9S Cass* lie/ $11. 95 Diskelte TRIPLE BLOCKADE is a two-to-three playcT graphics and sound action game. It is based on the classic video arcade game which millions have enjoyed. Using the Atari joysticks, the object is to direct your blockading line around the screen without running into your opponent(s). Although the concept is simple, the combined graphics and sound effect lead to "high GAMES PACK 1 (Available for all computers) Price: StO.95 Casselle/$14.95 Diskette GAMES PACK I contains ihe classic computer games of BLACKJACK, LUNAR LANDER, CRAPS, HORSERACE, SWITCH and more. These games have been combined into one large program for ease in loading. They are individually ac- cessed by a convenient menu. This collection is worth the price just for the DYNACOMP version of BLACKJACK. GAMES PACK II (Available for aU computers) Price: $10.95 Cassefle/ $14.95 Diskette GAMES PACK II includes the games CRAZY EIGHTS, JOTTO, ACEY-DUCEY, LIFE, WUMPUS and others. As with GAMES PACK I. all the games are loaded as one program and are called from a menu. You will partuul.ii U BBjoy DYNACOMP'S version of CRAZY EIGHTS. Why pay $7.95 or more per program when you can buy a DYNACOMP collection for just $10.93? MOON PROBE (Atari and North Sttr OOly) Price: $1 1.95 Cassette $15.95 Diskette This is an extremely challenging "lunar lander" program. The user must drop from orbit to land at a predetermined (argei on the moon's surface. You control the thrust and orientation of your craft plus direct the rate of descent and approach angle. Runs in I6K Atari. SPACE TRAP (Atari only, I6K) Price: $14.95 Ciss*tt*/$lis.95 Diskette This galactic "shoot 'em up" arcade game places you near a black hole. You control your spacecraft using the joystick and at- tempt to blast as many of the alien ships as possible before the black hole closes about you. CHIRP INVADERS (PET/CBM only) Price: $14.95 Cassette/ $1». 95 Diskette CHIRP INVADERS is an addictive game using action graphics. A Federation space station must be reached before the Chirps conquer [he Earth. Stationary obstacles, moving meteors, and the attacking Chirps must all be avoided for a successful journey. Good luck. SUPER SUB CHASE (Atari only) Price: $19.95 Cassette /$ 23 .9 5 Diskette SUPER SUB CHASE simulates a search and destroy mission. Set your course and keep an eye on the sonar readings as you hunt for the hidden submarine. Set the depth charge explosion depth and watch them sink towards the sub. This is an addictive game which takes advantage of the Atari's graphics and sound capabilities. One or two players. Joystick(s) required. ADVENTURE CRANSTON MANOR ADVENTURE (North Star and CP/M only) At lasi! A comprehensive Adventure game for North Star and CP/M systems. CRANSTON ^ you into mysterious CRANSTON MANOR where you attempt to gather fabulous treasures I animals and robots who will not give up the treasures without a Tight. The number of rooms descriptions aic much more elaborate than the current popular series of Adventure programs, r class. Play can be stopped al any time and the status stored on diskette. Not available in S44' I greater and the associated iking this game the top in its CP/M format. GUMBALL RALLY ADVENTURE (North Star only, 48k) Price: $21.95 Diskette Take part in ihis outlaw race from the east coast to the west coast. The goal is to find your way to Ihe finish line while main- taining the highest possible speed. You may choose one of five cars available at (he garage. The choice will affect your speed and range, Remember to take spare pans and don't get caught speeding! UNCLE HARRY'S WILL (North Star only, 40K) Price: $24.95 Diskette Uncle Harry hat died and ha^ left you everything. However, he has neglected to mention where everything is! Instead, his will consists of a poem which contains clues You will have to travel all over the United States both by car and on foot to solve the puzzle, and there are over 300 locations to probe. Be careful and watch out for red herrings! SPEECH SYNTHESIS DYNACOMP is now distributing the new and revolutionary TYPE-'N-TALK™ (TNT) speech synthesizer from Votrax. Simply connect TNT to four computer's tarsal interface, enter text from the keyboard and hear the words spoken. TNT is the easiesl-to- program speech synthesizer on the market. It uses the least amount of mensn ..;>.: j >: ,« ides the most flexible vocabulary available anywhere! TYPE-'N'-TALK List price $375. DYNACOMP'S price $319,95 plus $5.00 for shipping and handling. TALK TO ME (T'N'T Atari only, 24K) Price: $14,95 Ca*sette/$li. 95 Diskette This program presents a superb tutorial on speech synthesis using the Atari 800 and TYPE 'N TALK™. TALK TO ME will illustrate normal word generation as well as phoneme generation. The documentation includes many helpful programming tips. TALK TO MSB has been demonstrated on network (CBS) TV! MISCELLANEOUS CRYSTALS (Atari only) price: $ 9.95 Cassette /$ 13.95 Diskelte A unique algorithm randomly produces fascinating graphics displays accompanied with tones which vary as the patterns aie built. No two patterns are the same, and the combined effect of the sound and graphics are mesmerizing CRYSTALS has been used in local stores to demonstrate the sound and color features of the Atari. Runs in I6K Atari NORTH STAR SOFTWARE EXCHANGE (NSSE) LIBRARY DYNACOMP now distributes the 23 volume NSSE library. These diskettes each ci standing value for the purchase price. They should be pari of every North Slat user for details regarding the contents of the NSSE collection. Price: $9.95 each/$7.95 each (4 or more) The complete collection may be purchased for $149.95 $**" DISKETTES (soft sectoretJ/len sectored) As you might imagine. DYNACOMP purchases diskettes in large quantities and at » ings along to you! Circle 158 on inquiry card. BUSINESS and UTILITIES MAILMASTKR (Atari diskette only) MA1LMASTER is a very versatile software tan hold over 600 customer entries contain! so that entries may be made and edited with ease. The may be printed 1.2 or 3 up, and all sorting (zip code I Price; S39.95 Diskette id manipulating mail lists and mini daia bases. fcach disk •i key words and a phone number. The display is marked alus (e.g.. disk space left, options, etc.) is shown at all times. Labels d alphabetic) is performed by a fast machine language program. PERSONAL FINANCE SYSTEM (Atari and North Star only) Price: $39.95 Dtikette PLS is a single diskette, menu-oriented system composed of ten different programs. Besides recording your expenses and tax deductible items. WS will sun gad summarize expenses by payee, and display information on expenditures by any of 26 user defined codes by month or by payee. PFS will even produce monthly bar graphs of your expenses by category! This powerful package requires only one disk drive, minimal memory (24K Atari, 32K North Star) and will store up to 600 records per disk (and over 1000 records per disk by making a few simple changes to the programs). You can record checks plus cash expenses so that you can finally see where your money goes and eliminate guesswork and tedious hand calculations. Contains high speed machine language sort. Pt-S has been demonstrated on network (CBS) TV! FAMILY BUDGET (Apple and Atari only) Price: $34.95 Diskette FAMILY BUDGET is a very convenient financial record-keeping program. You will be able to keep track of cash and credit expenditures as well as income on a daily basis. You can record tax deductible items and charitable donations. KAMILY BUDGET also provides a continuous record of all credit transactions. You can make daily cash and charge entries to any of 2) different expense accounts as well as to 5 payroll and tax accounts. Data are easily retrieved giving the user complete control over an otherwise complicated (and unorganized!) subject. Price; S49.95 Diskette s for facilitating efficient two-way communications ration you may connect to a data service (e.g., The onto your diskette for later viewing. This greatly re- ay also record the complete contents of a communications session. :. may be built off-line using the support text editor and later "up- smart terminal. Even Atari BASIC programs may be uploaded. er as controlling input for a time-share system. That is, you can set and the Atari will transmit them as needed; batch processing. All IMF! INK (Atari only) This software package contains a menu-driven colleclii through a full duplex modern (required for use). In on SOURCE or MicroNet) and quickly load data such as si duces "connect time" and thus the service charge. You r Additionally, programs written in BASIC, FORTRAN, < loaded" to another computer, making the Atari a ver Further, a command file may be built off-line and used I; up your sequence of time-share commands and program this adds up lo saving both connect lime and your time. PAYE1VE (Apple Ii plus diskette, two drives required) Price: S149.9S This is an enormously flexible employee payroll system with extraordinarily good human engineering features, PAYFIVE prints checks and compiles the required federal, state and local forms for up lo 148 employees. The pay methods may be hour- ly, salary, commission or any combination. There are multiple options for pay periods, and they also can be used in any com- bination. PAYF1VE includes many other features and comes extremely well documented with a 200 page manual. The manual may be purchased separately for S30, and that payment later applied to [he software purchase. SHOPPING LIST (Atari only) Price; $12.95 Cassetle/516.95 Diskette SHOPPING LIST stores information on items you purchase at the supermarket. Before going shopping, it will remind you of all the things you might need, and then display lor optionally print) your shopping list and the total cost. Adding, deleting, changing and storing data is very easy. Runs with 16K. TAX OPTIMIZER (North SIM only) Price: $59.95 Dtikette The TAX OPTIMIZER is an easy-to-use. menu oriented software package which provides a convenient means for analyzing various income lax strategies The program is designed to provide a quick and easy data entry. Income tax is computed by all tax methods (regular, income averaging, maximum and alternate minimum tax). The user may immediately observe the lax effect of critical financial decisions. TAX OPTIMIZER has been thoroughly field tested in CPA offices and comes complete with the current tax tables in its data files. TAX OPTIMIZER is lax deductible! LITIL (Apple only, 48K) UT1L is a disk-oriented utility system which pc the, bit (nibble or byte) level. With UTH. you ca tor pointers, reallocate seclors (e.g. bad sectors experienced programmer. TURNKEY AND MENU (Atari only) Prke; $17.95 Diskette TURNKEY is a utility program which allows you to create autoboot/autorun diskettes easily. Simply load and run TURN- KEY, load the program diskette to be modified, and answer the questions! I he I I.KNKLY diskette also comes with DOS 2.0 and includes another program, MENU. MENU lists the contents of your diskette alphabetically, and permits the running of any BASIC program on Ihe diskette by typing a single key. TURNKEY and MENU provide you with the ability to run any program on your diskette by simply turning on the computer and pressing a single key. STOCKAISi} (Atari only) Price: $29.95 Diskette STOCKA1D provides a powerful set of tools for stock market analysis. With STOCKAID you can display point and figure charts, as well as bat charts with oscillators. You can also examine long term moving averages and on-balance volume features. STOCKAID allows you to input daily data with a single diskette storage capability of 239 days X 16 stocks Included are slock dividend and split adjustment capabilities. A very professional package! SHAPE MAGICIAN (Apple II, 48K, diskette only) Price: $29.95 Al last! An utility for painlessly creating graphics shapes for the Apple. Create, edit and save up to 30 shapes which can then be used to develop arcade games or to simply enhance your programs. Add that professional touch! d perform nwayodl d operations, For EDUCATION HODGE POOGE (Apple only, 48K Applesoft or Integer BASIC) Priced MS Diskette Let HODGE PODGE be your child's teacher. Pressing any key on your Apple will result in a different and intriguing "hap- pening" related to the letter or number of the chosen key. The program's graphics, color and sound are a delight for children from ages 1 W to l. HODGE PODGE is a non-iniimidating teaching device which brings a new dimension lo the use of com- puters in education See the excellent reviews of ihis very popular program in 1NFOWORLD and SOFTALK. TEACHERS' AIDE (Atari only) Price: $13.95 Cassette/ SI 7. 95 Diskette TEACHERS' AIDE consists ol three basic modules contained in one program, The first module provides addition and sub- traction exercises of varying levels of difficulty. The second module consists of multiplication problems in which the student may be tested both on the final answer and/or on the subtotal answers in ihe long hand procedure. Several levels of complexity are provided here as well. The third module consists of division problems; one particularly nice feature of the division module is that the long hand division steps can be displayed along with Ihe remainder in order to clearly demonstrate the procedure by which the remainder is derived. Using TEACHER'S AIDE is not merely a drill, but rather a learning experience, PHARMACOLOGY UPDATE (PET only) Price: $169.95 Cassette/ SI 49.95 Diskette This is DYNACOMP's first educational software entry for the medical profession (more are coming!). PHARMACOLOGY UPDATE was written by a R.N. as a masters project, with the aid of a practicing pharmacologist and an electronics instructor. I hfe package comes In p»0 parts The first part is a 200 page manual which is divided into 1 1 sections. Each of these sections provides both concise information and probing questions. The second pan consists of 1 1 programs that are keyed to the text and which test Ihe degree of your understanding of Ihe text material. This package has greal educational value lor the begin- ning student as well as the professional interested in an efficient way to review and update his or her knowledge. Available on cassettes (II) or diskette. TEACHER'S GRADEBOOK (Apple 48K dual/ single drive) TEACHER'S GRADEBOOK. is a complete password protected record-keeping systt nine users, and each user may have daia for up to nine classes on one disk (with up to tion which can be entered, edited and processed includes rosters, absences and grades. the screen I or printed in various ways, with automatic weighted averaging is both welfwritlt i: doc Price $49.95 Diskette its per class). Typical informa- y reports may be displayed (on a grades. This system has been ORDERING INFORMATION Within Norlh America: Add $2.00 Outside North America: Add 15% ( Quantity Discounts Deduct I0°?o when ordering 3 or mo K P S" C P/M Disks Add J 2. SO (o the listed diskette pric Microsoft MBASK o: BASK SO. e for " CP'M Disks liable on K" CT M disl I. Dealer discount schedules a " floppy disk (IBM soft secto is also available on 5'/i" disks. North Star and Osborne form software dealer Write for detailed descriptions of these and o DYNACOMP, Inc. (Dept. B) 1427 Monroe Avenue Rochester, New York 14618 24 hour message and order phone: (716)442-8731 Toll free order phones: (800)828-6772 (800)828-6773 Office phone (9AM-5PM EST): (716)442-8960 New York Slate residents please add 1% NVS salts tax. STATISTICS and ENGINEERING DIGITAL FILTER (Available for all computers) DIGITAL FILTER is. a comprehensive data processing program w Price: $39.95 C e/S43.95 Diskette s l hi: J choose from a menu of filter for is. In the explicit design mode the shape directly entering points along the icsired filter curve. In the 1 menu mode, id ,.ucd to varying degrees a ctordingto the number ot points used in smoothed wilh a Hanninx tuner on. In addition, multi-stage Butterwort FILTER include plotting of the d aia before and after filtering, as well as d are convenient data storage, retri Eval and editing procedures. ,e frequency transfer function is specified h\ x pass, high pass and ban ':.■:; I ■;■,>:■ ' Iculation. These filters may optionally also bi- ers may be selected. Features of DIGITAL display of the chosen filter functions. Also included DATA SMOOTHER (Not available for Alan) This special data smoothing program may be used lo rapidly derive useful informs data which are equally spaced. The software features choice in degree and range o: derivative calculation. Also included is automatic plotting of the input data and si FOURIER ANALYZER (Available for all computers) Use this program to examine the frequency spectra of limited duration signals. Th plotting of the inpul data and results. Practical applications include th -:.-i-.... , ■ if... ..,:■•. :;• i" ' .: ..:ii v. TEA (Transfer Function Analyzer) This is a special software package which may be used to evaluate the transfer l' filters by examining their response to pulsed inputs, TFA is a major modificati engineering -oriented decibel versus log-frequency plot as well as data editing fe signed for educational and scientific use. TFA is an engineering tool. Availal e/S23.95 Diskette Price: 519.95 C«sselte/S23.95 Diskette lions ■:>! svstcms such as hi-fi amplifiers and >f fOURJF.k ANAL V/ IK and contains an es. Whereas FOURIER ANALYZER is de- or ail computers. HARMONIC ANALYZER (Available for all computers) Prke: $24,95 C«ssetie/S28.95 Diskette HARMONIC ANALVZER was designed for the spectrum analysis of repetitive waveforms. Features include data file genera- tion, editing and storage/retrieval as well as data and spectrum plotting. One particularly unique facility is that the inpul data need not be equally , paced 61 in order The original data is sorted and a cubic spline interpolation is used to create the data file required by the FFT algorithm. FOURIER ANALYZER, TFA and HARMONIC ANALYZER may be purchased together for a combined price of S51.9S (three cassettes) and $63.95 {three diskettes), REGRESSION I (Available for ail computers) Price: S19.95 Cwjette/S23.95 Diskette REGRESSION I is a unique and exceptionally versatile one-dimensional least squares "polynomial" curve fitting program. Features include very high accuracy; an automatic degree determination option: an extensive internal library of fitting func- tions; data editing; automatic data, curve and residual plotting; a statist i ,.1 in a lysis {eg standard deviation cu relation coeffi- cient, etc.) and much more. In addition, new fits may be tried without reentering the data. REGRESSION 1 is certainly the cornerstone program in any data analysis software library. REGRESSION II (PARAFIT) (Available for aU computers) Price: SI 9. 95 Cassette /S23. 95 Diskette PARAFIT is designed to handle those cases in which the parameters are imbedded (possibly nonlinearly) in the fitting func- tion. The use ; functional form, including the parameters (Ad), A(2), etc.) as one or more BASIC statement lines. Data, results and residuals may be manipulated and plotted as with REGRESSION I. Use REGRESSION I for polynomial fitting, and PARAFIT for those complicated functions. MULTILINEAR REGRESSION (MLR) (Available for all computers) Price: $24.95 Cassette/S2S.95 Diskette MIR is a professional software package for analyzing data sets containing two or more linearly independent variables Besides performing the basic regression calculation, this program also provides easy to use data entry, storage, retrieval and editing functions. In addition, Ihe user may interrogate the solution by supplying values for the independent variables. The number ol variables and data size is limited only by (he available memory. REGRESSION I, II and MULTILINEAR REGRESSION may be purchased together for 151.95 (three cassettes) or S63.95 A NOVA (Not available on Atari cassette or for PET/CBM) Price: 139.95 Cassette /S43, 95 Diskette In the past the ANOVA (analysis of variance) procedure has been limited to the large mainframe computers, Now DYNACOMP has brought the power of this method to small systems. For those conversant with ANOVA, the DYNACOMP software package includes the I -way, 2-way and N-way procedures. Also provided are the Yates 2 K - p factorial designs For those unfamiliar with ANOVA, do not worry. The accompanying documentation was Written ,n a •iiron;,! fashion (by a pro- fessor in the subject) and serves as an excellent introduction to the subject. Accompanying ANOVA is a support program for building the data base. Included are several convenient features including data editing, deleting and appending. BASIC SCIENTIFIC SUBROUTINES, Volumes I and 2 (Not available for Atari) DYNACOMP is Ihe exclusive distributor lor tile software keyed to the popular texts BASIC SCIENTIFIC SUBROUTINES, Volumes I nnd2by F, Ruckdeschel (see advertisements in BYTE magazine). These subroutines have been assembled according to chapter. Included with each collection is a menu program which selects and demonstrates each subroutine. Volume I Collection #1 : Chapters 2 and 3 - Data and function plotting; complex variables and functions. Collection #2: Chapter 4 - Extended matrix and vector operations. Collection #3: Chapters 5 and 6 ■ Random number generators (Poisson, Gaussian, etc.); series approximations. Price per collection: SI 4.95 Cassette/I 18. 95 Diskette All three collections are available for S39.95 (three cassettes) and S49.95 (three diskettes). - Linear, polynomial, multidimensional, parametric least squares. Collection *2: Chapter 2 - Series approximation teehniqt Collection #3: Chapter 3 - Functional approximations b) Collection #4: Chapter 4 - CORDIC approximations lo trigonometric, hyperbolic, functi shifting, etc.). iponential and logarithmic on. LaGrange, splines). n #5; Chapter 5 - Table interpolation, differentiation and integration ( Chapter 6 - Methods for finding the real rools of functions. Collection HI: Chapter 7 - Methods for finding the complex tools of functions. Collection #8: Chapter 8 - Optimizatkw &} Steepest descent. Price per collection: $14.95 Cassette/! 18. 95 Diskette All eight collections are asailable for S99.9J (eight cassettes) and $129.95 (eight diskettes). Because the texts are a vital part of the documentation , BA SIC SCIENTIFIC SUBROUTINES, Volumes 1 and 2 are available from DYNACOMP: BASIC SCIENTIFIC SUBROUTINES, Vol 1 (319 pages): $19.95 + 75* postage BASIC SCIENTIFIC SUBROUTINES. Vol 2 (790 pages): $23.95 + $1.50 postage See reviews in KILOBAUD and Dr. Dobbs. SOFTNET (Apple II, 4«K, diskette only) Price S129.95 SOFTNET may be used to create models of liquid pipeline systems to evaluate their flow performance. Up to 1 50 nodes with up to 150 connecting elements may be simulated, and models may be combined to form yet larger models. If you are involved 1 fluid flow problems, building plumbing, or similar situations, this is an ideal analysis MATCHNET (TRS-80 only) Price: $19.95 Ci»rtte/S23.95 Diskette II often lakes days 10 iieiarivesy Optimise an L, Pi or T matching network for a particular application. Take a few minutes wilh MATCHNET and you will have ihe Q, frequency response and reflection coefficients for any of twelve matching networks. You inpul the source and load impedance and MA I ( HNET calculates the R, C. (and L) values and plots (and/or prints) the frequency response and reflection coefficients for each configuration. The reviewer of this program remembers when he use to do this by hand and loves MATCHNET! ACTIVE CIRCUIT ANALYSIS (ACAP) (48K Apple only) Price: $25.95 C*sse«e/S29.95 Diskette With ACAP you may analyze the response of an active or passive component circuit The circuit may be probed at equal steps in frequency, and the resulting complex voltages at each component juncture examined; the frequency response of a filter or amplifier may be completely determined with respect to both amplitude and phase. In addition, ACAP prints a statistical analysis of ihe range of voltage responses which result from tolerance variations in the components. ACAP is easy to leam and use. Circuit descriptions may be saved onto cassette or diskette to be recalled at a later time tor execution or editing. ACAP should be part of c- i designer's program library. LOGIC SIMULATOR (Apple only; 48K RAM) Price; $24.9S Cassette/S28.95 Diskette Test your complicated digital logic design wilh respect lo given set of inputs to determine how well the circuit will operate. The elements which may be simulated include multiple input AND, OR, NOR, EXOR, EXNOR and NAND gates, as well as in- verters, J-K and D flip-Hops, and one-shots. Inputs may be clocked in with varying clock cycle lengths/displacements and delays may be introduced to probe for glitches and race conditions. A liming diagram for any given set of nodes may be plotted using HIRES graphics. Save your breadboarding until the circuit is checked by LOGIC SIMULATOR. NUMBERKRUNCHER (TRS-80 only) This program is the most complete numerical analysis system available fi set having a six character name. It includes complete data editing facilit: analyses available are multiple linear regression and correlation determin; Price: S69.95 Cassette/S73.9S Diskette he TRS-80. It can handle up to 255 data sets, each and convenient data input/output capability. The n of residuals, data transformations and extensive append :■- wind h allow the user 1c Price: $39.95 Cass*lte/$43.95 Diskette te (build, edit, merge), format and print t, average, variance, standard deviation) n can also be employed to create a data STATSORT (TRS-80 only) STATSORT consists of several menu selected progra files, (machine) sort ihem on any field, and numerically analyze (maximum, minimum, tabulated data. STATSORT is well documented and easy to use. The cassette version type which can be read by the Radio Shack Advanced Statistical Package, STATTEST (TRS-80 only ) This is a statistical inference package which helps you make wise decisions in the face of uncertainty. In an interactive fashion you can build and edit data files, and tesl the differences in means, variances and proportions. STATTEST will also perform data analysis as well as do linear correlation and regression. This menu-directed statistical worknui sc is rounded out with a chi- square contingency test and a (uniform and norma!) random sample generator. The documentation is written by a College pro - -. ABOUT DYNACOMP DYNACOMP is a leading distributor of small system software with sales spanning the world (currently in excess of 50 countries). During the past three years we have greatly enlarged the DYNACOMP product line, but have maintained and improved our high level of quality and customer support. The achievement in quality is apparent from our many repeat customers and the software reviews in such publications as COMPUTRONICS, 80 Soft- ware Critique, A.N.A.L.O.G., Softalk, Creative Computing and Kilobaud. DYNACOMP software has also been chosen for demonstration on network television. Our customer support is as close as your phone. It is always friendly. The staff is highly trained and always willing to discuss products or give advice. Circle 158 on inquiry card. MOD III TRS-80 Model III Features for Your Model I Add video line print, selectable cursor, and automatic key repeat to your TRS-80 Model I. I'm a satisfied owner of a Radio Shack TRS-80 Model I, but I can't help envying some of the features of the new Model III. Its video line print, block cursor, and automatic key repeat are indeed useful additions to the TRS-80's repertoire of pro- gramming features. Numerous video-line-print and cursor routines have been published as individual utility programs; however, because they are individual programs, only one can be used at a time. My working with a friend's Model III spawned dreams of a single utility program that would provide all these capabilities for my Model I. My file of programs included video- line-print and cursor routines, so my thoughts turned to combining the two into a single utility program. An automatic key repeat, a user- selectable cursor, and an audible key beep also crept into this programming daydream. The dream became reality only after several unsuccessful attempts to combine existing program routines. Initial efforts produced workable pro- grams, but not without adverse side effects. High memory overhead offset the benefits provided, and the key- beep feature resulted in slow key- board response time. When used with my editor/assembler, the utility routines preempted the memory oc- 380 April 1982 © BYTE Publications Inc Joe W. Rocke 224 West Benson Ridgecrest, CA 93555 cupied by the automatic key repeat. Programming is somewhat akin to building construction. It is often easier to build anew than to remodel the old. With this in mind, I took a fresh program approach, literally starting with a blank video screen. This effort resulted in a utility pro- gram that I call MOD III. The MOD III utility pro- gram uses fewer than 1 70 bytes of RAM, making it practical even on a 1 6K-by te memory system. MOD HI Features The MOD III program source code presented in listing 1 provides video line print, a block cursor, and auto- matic key repeat. This program also provides two added side benefits: the cursor style is user-changeable, and the key repeat automatically provides key debounce. Better still, the pro- gram uses fewer than 170 bytes of random-access read /write memory (RAM). This low memory overhead makes the program practical for use with a 16K-byte memory system. MOD III is compatible with most disk operating systems (DOS), the Beta cassette system, the EDTASM + editor/assembler, and Level II BASIC. It is written for a Level II 48K-byte system, but may be mod- ified for a 16K- or 32K-byte RAM system by changing the starting ad- dress. Changes required for DOS are annotated in the source code remarks (see listing 1), MOD III was initially written in assembly language to conserve memory space and provide the quick response required for the automatic key -repeat feature. The original plan was to place the program at a low RAM location just under the BASIC block and reset the BASIC pointers. This would eliminate the need to set memory size before loading MOD III. However, in this location it would be wiped out by disk BASIC or by pro- grams such as EDTASM + . Changing the program to load to high memory provided the system and program compatibility desired. Memory Protect Because MOD III starts at a high RAM address, it's necessary to set memory size before loading the pro- gram. By calculating the number of bytes required for the program, you can establish the starting address that will load the program to the very top of memory to conserve RAM space. Text continued on page 386 I with our variety of qui s. ASAP carries only the highest quality floppy disk drives, to provide you with years of trouble-free service and superior performance. Data Trak™ double-sided, double-density drives from Qume® feature state-of-the-art technology. You get superior data integrity through improved disk life, data reliability and drive serviceability. Data Trak™ 5 (ANSI 5W compatibility) Call for price Data Trak™ 8 (IBM compatibility) Call for price Shugart drives have been setting industry quality and reliability standards for years. Shugart's Bi-Compliant™ head assembly provides superior media compliance and high reliability. Model 801 (standard floppy) $400.00 Model 850 $640.00 ASAP also provides a full line of high reliability disk drive subsystems. For superior quality, high reliability disk drives, contact ASAP today. Part No. — Description* Price HDC8/1-HD — Cabinet with (1) Priam 10 megabyte hard disk drive with Microbyte Controller Call for price HDC8/1F+1HD — Cabinet with (1) Qume® DT-8 double-sided, double-density drive, and (1) Priam 10 megabyte hard disk drive with Microbyte Controller Call for price CAB8H — Dual cabinet for 8". floppy disk drives (horizontal mounting) $ 225.00 CAB8V — Cabinet for 8" floppy disk drives (vertical mounting) $ 225.00 CAB8H/V+1S — Dual cabinet with (1) Shugart SA801R installed (horizontal or vertical mounting) ........ $ 675.00 CAB8H/V+2S — Dual cabinet with (2) Shugart SA801R's installed (horizontal or vertical mounting) .$1055.00 CAB8H/V+1Q — Dual cabinet with (1) Qume® DT-8 double-sided double-density drive installed (horizontal or vertical mounting) -.. $ 755.00 CAB8H/V+2Q — Dual cabinet with (2) Qume® DT-8's double- sided double-density drive installed (horizontal or vertical mounting) $1225.00 X5 — Cabinet for desk top mainframe (small power supply) $ 200.00 800D — Cabinet for desk top mainframe (standard power supply) S 255.00 *AII cabinets come complete with power supply, fan and internal cables. asaii computer I computer productsjnc. ftjJSHSB F Willnw St Sional Hill CA 90806 I ' « HJ U3 I 'LUUO Toll free outside California: (800)421-7701 Inside California: (213)595-6431 1198 E. Willow St., Signal Hill, CA 90806 ASAP offers a 30-day buyer protection policy: full money-back guarantee if not totally satisfied: Ordering information: name, address, phone, ship by: UPS or truck. Please call for shipping charges. Terms: We accept cash, check, money orders. Visa and Master Charge (U.S. funds only). Tax: 6% Calif, res. COD's and terms available on approval (school PO's accepted). 1 Circle 460 on inquiry card. BYTE April 1982 381 Circle 314 on Inquiry card. The source code listing for MOD HI. The key-beep feature has been disabled Listing 1 (see lines 850 through 1100). Remove the semicolons to use that feature. \«/ryx 00010 ; * + : * :+: :+; + : +: + : :+r *: :+: :+: :+. +: +: :+: :+: ;+: +: :+: ;+i :+: :+; * :+: s+: *: *e :+: +: +: * * :+: *: :+: :+: M :+: * :+: :+: :+: *: :+: # :+: :+: * :+. * -+: :+r :+: + >f : software 00020 ; ** KEY-REPEAT AND BLOCK CURSOR ** 00030 ;+* WORKS WITH 'DOS' - 'EDTASM' - 'BASIC » ETC. ** 00040 J +H--+: *:+:+>f:* + + + + + :+:*+: + :+:+ + :+"+r :+: + + + GUARANTEED LOWEST PRICES' 00050 To celebrate our opening, we are 00060 00070 matching any advertised price. Just show us the ad. 00080 00090 00100 ', +: * : :+: :+: >f : :+: :+: +: * +: :+: :+: *: ;+: :+: :+: +: :+: :+: +: * >f : * :+: :+: +: :+: :+: :+: +: :+; r+; :+: * :+: :+: *: +. ;+: :+: :+: :+: +: :+; :+: >f : :+: + :+: ■+; : + : : + : *t * •+ : + ; !** FOR JUST 'BLOCK CURSOR' - USE LINES 1730 UP ** ;+* SEE 'HOOK' LINES: 1170 THRU 1270 ** 1 ORDER TOLL FREE • Outside wi 1 1 1-800-826-1589 00110 5 * * ■+: * *: + * :+: +: +: *: :+: + * * jf : ;+-. :* -+. :+: * :+: :+r *: r+: + : * :+: :+: +: :+: :+: 3+: * : * :+- :+: * :+: * * * ;+: •+: jf : -4: +: * * : +: * * :+: :+: +: :+: 00120 ACCESSORIES 00130 ORG 0FF4DH 548K - CHANGE FOR LESS 1 ! ! Apple II Dual Thermometer w/sottware 260.00 00140 Mountain Expansion Chassis 625 00 00150 !** IF KEY BEEP CPS Multifunction 199.00 00160 Mountain Music System 395.00 100,000 Day Clock 375,00 00170 ST HL, START! ! PUT A ' HOOK' INTO Mountain Clock 252.00 SuperfalkerSD2Q0Q 199.00 001S0 LD (4016H),HL ^KEYBOARD CONTROL A/D + D/A 299.00 00190 LD HL, BEGIN ;FOR 'ZX' AND BLOCK CCS 12K ROM/PROM Board 99 00 CCS A/D Converter Board 99 00 00200 LD C401EH),HL 5CURSOR ROUTINES CCS Serial Asynch. Board 139.00 00210 LD A, SFH ; ■ BLOCK CURSOR' CCS Calendar/Clock Board 99.00 00220 LD C 16409), A 'PUT IT IN ' POKEABLE ROM' VOTRAXType-n-Talk 375.00 ADALAB Package 495 00 00230 DOS Dater 49 00 00240 JP 402DH ;NEWDOS80 SYSTEM ABT Numeric Keypad 125.00 ABTSoftkey 150 00 00^50 ABTBarwand 195.00 00260 JP 1A1SH FOR BETA, TC~3 BASIC OR ABT Cash Box 295.00 ABT Pascal Tools I or tl 75 00 00270 ' NO SYSTEM AT ALL Scitronic Remote Controller 249.00 00280 " OR NOTE: BELOW Scitronic Energy Watcher 1 Ph. 349.00 Apple Speed Controller 69.00 00290 +: >f: * ; *. }f: M Jf: >f : * At : :+: +: Jf : :+: :+: *: +: :+: +: :+: +: :+: * :+: * * *t * 5f : +:+.:+. * :+: ;+: :+: :+: :+: :+: •+: +: :+: ;+: :+r +: +: :+: :+: :+: :+: 4: * :+'■ H-: »♦« +• Applescope (your Apple as an Oscilloscope) 595.00 00300 " ** NOTE: TRSDOS, NEWDOS+, ECT. MPlY NOT ACCEPT THE «•«* Scope Driver 49.00 Videx Videoterm ...... 319.00 00310 ■ ** ROM III PROGRAM IN COMMAND MODE BUT WILL RUN IN ** Videx Enhancer II 148.00 00320 ' mm DISK BASIC. LOAD ROMIII/CIM THEN BASIC mm K&D Enhancer 115.00 Videx Character Sets 29.00 00330 i ** DEFUSR1=&HFF4D: PRINT US R 1(0) ** Echo Speech Synthesizer 225.00 00340 ' *+: j+: 5tcj1.:>f :*+ ++++: + + +::+:+++ + :+:*+ + * + Jf:***>|4**H«^.Jts*5*c** + + *4;* + >f:4: + * + »t:*-**if: Upper/Lower Character 39.50 00350 Joysticks 4 59.00 ALS Smarterm 379.00 00360 ALSZ-Card 269.00 SSMA10s/p interface + cable 195.00 Scott Instrument VET (2) 795.00 00370 - +:* +:+:+:+ * * *: *: +: +: if: + * * +: +: :+: :+: >f: +: * +: iff jf : :+: :+: H-: +: jf : *+: :+: +: :+: •+: >f : * : :+: :+: :+: * : :+: :+: :+: +: :+: :+: +: +; ;+: :+: >f i M :+= :+: 0038 5 mm MEMORY SIZE-? PROTECTION STARTS HERE mm ALF Music Card MC1 195.00 ALF Music Card MC16 245.00 00390 ' ** EQUALS 65375 FOR 48K ** ALF Game I/O 16.00 00400 ' mm*#mmmmmmmmmmmmm* ALF Timing Mode I/O 18.00 00410 ■ ALF Ear Training 49.95 ALF Albums 14.95 Microspeed II 495 00 00420 £ 00430 >TART1 LD HL,4036H ;HL ■ KEYBOARD BUFFER BC3801H ?BC ■ ROW ADDRESS POINTER LD . . .AND MANY MORE! 00440 LD D 7 00H ;'D' = ROW COUNT TO 6 00450 L .PI LD A, (BO ; ANYTHING PRESSED ?? Quoted prices valid for stock on hand and sub- 00460 LD E,A ;PUT IT IN 'E' FOR TEST ject to change without prior notice. 00470 AND E ; CHECK ALL BITS FOR Call for price information: 00480 JR NZ,LP4 -,NOT ZERO GOTO COUNTER Printers ■ Epson, Okidata, Microline, NEC, 00490 LD (HL),A ;LOAD IT TO MEMORY C. ITOH. Qume. Diablo, Anadex, IDS, MPI, Microtek, Printek. 00500 L _P2 INC D 5NEXT KEYBOARD ROW Monitors - Amdek, Sanyo, Hitachi, NEC, 00510 INC L ;BUMP KEYBOARD BUFFER Kaga/TSK. I 00520 RLC C ; POINT TO NEXT ROW Modems • Novation, Hayes. 00530 LD A,C 3 PUT IT IN A FOR TEST Disk Drives - Percom, Corvus. Morrow, CCS, etc. 00540 SUB 80H ! SUBTRACT 128 DECIMAL Plotters • Watanabe. 00550 JR NZ,LP1 SNOT ZERO? CHECK AGAIN! 00560 LD At (HL) ?GET COPY OF OUR CHAR, Ask for our FREE catalog. 00570 LD B,07H ; COUNT OF SEVEN For Software 00580 L _P3 DEC L ; BACKUP KEYBOARD BUFFER see our other ad, page 30 00590 ADD A, (HL) ;ADD MEMORY TO ' A' 00600 00610 DJNZ CP LP3 ?GO FOR COUNT IN ' B' 00H ?CHECK FOR ZERO IN 'A' Please: • Wisconsin residents - add 4% sales tax 00620 LD A,00H 3 ZERO *A' REGISTER • Foreign orders - please add 15% • Add $2,50 for shipping per software and 00630 RET NZ ; RETURN WITH CHARACTER small item. Call regarding others. 00640 LD (401 AH), A ' PUT IN KEY CONT. BLK We Welcome: * Visa, MasterCharge - (Add 4%) • Checks (Allow 1-2 weeks for clearing) 00650 RET ' RETURN TO PROGRAM 00660 L _P4 AND (HL) 1 CHECK EACH BIT FOR •COD ($1.50 per shipment) TOLL FREE • Outside Wisconsin: 00670 00680 JR LD Z,LP5 ;go IF IT IS A, (401AH) ;GET BYTE FROM CONT. BLK 1-800-826-1589 _ For Technical Info & in Wisconsin: ^k ^J Aj 00690 INC A ?ADD CI) TO IT 00700 LD (401AH),A 5PUT IT BACK FOR COUNT 715-848-2322 %jfln# Oryx Software Dept. a m^^rM 00710 CP 0FFH 3= 255 DECIMAL ? 00720 JR NZ,LP2 ;NO a LOOP BACK P.O. Box 1961 • Wausau, WI 54401 W W /» 00730 DEC A ? SUBTRACT (1) Listing 1 continued on page 384 v. \mw 382 April 1982 © BYTE Publications Inc Do you have a restless urge to program? Do you want the instant respect that comes from being able to use technical terms that nobody under- stands? Do you want to strike fear and loathing into the hearts of DP managers everywhere? If so, then let the Famous Programmers 9 School lead you on . . . into the world of professional computer programming. What Do Top Programmers Earn? Despite popular myths, some pro- grammers actually do earn a living doing the work they love. Other, less fortunate programmers work in their spare time at home while watching television. Either way, your potential earnings as a computer programmer could reach into the millions, possibly even into the billions, of dollars. Of course, your success depends a lot on your abilities, luck, shoe size, the phase of the moon, etc. Is Programming for You? Programming is not for everyone. But if you have a desire to learn, we can help you get started. All you need is the Famous Programmers ' Course and enough money to keep those les- sons coming month after month. Take Our Free Aptitude Test To help you determine if you are qualified to be a programmer, take a moment to try this simple test: 1) Write down the numbers from zero to nine and the first six letters of the alphabet (Hint: 0123456789ABC- DEF). 2) Whose picture is on the back of a twenty- dollar bill? 3) What is the state capital of Idaho? If you managed to read all three questions without wondering why we asked them, you may have a future as a computer programmer. A New Kind of Programming. They say a good programmer can write 20 lines of effective program The staff of the Famous Programmers' School includes some of the best known names in the microcomputing field. From left to right: Bennett Lisp (with cigar), Rod Snobol (with feelers), Bruce Fortran (eating cigar), Rudolf Forth (natty attire), Ignatious "Call Me Blaise" Pascal (feelers, cigar and flow- chart), and the immortal Red Basic (smug look). per day. With our unique training course, we'll show you how to write 20 lines of code and lots more besides. Our training course covers every programming language in ex- istence, and some that aren't. You'll learn why the on/ off switch for a computer is so important, what the words FATAL EBROR mean, and who and what you should blame when you make a mistake. Student Successes Many of our students have gone on to achieve great success in all fields of programming. One former student developed the concept of the per- sonalized form letter. Does the phrase, "Dear Mr. (insert name), You may already be a winner!," sound fa- miliar? Another student writes, "After only five lessons I sold a 'My Most Unforgettable Program' article to Corrosive Computing magazine." Another of our graduates writes, "I recently completed a database- management program for my depart- ment manager. My program touched him so deeply that he was speechless. He told me later that he had never seen such a program in his entire career. Thank you, Famous Program- mers' School; only you could have made this possible." Don't Delay Send for our introductory brochure that explains in vague detail the op- eration of the Famous Programmers' School, and you'll be eligible to win a possible chance to enter a drawing, the winner of which can vie for a set of free steak knives. If you don't do it now, you'll hate yourself in the morning. Famous Programmers' School Dept, APRFOL P.O. Box 463 Paulsborough, NH 03458-0463 I Yes, I want the brochure describing this incredible offer. I enclose $1000 in small unmarked bills to cover the cost of postage and handling. (No live poultry, please.) Send the information to: Name: Address:. City, State :_ . Zip:_ Our Slogan: Top down programming for the masses. Circle 415 on Inquiry card. Keep static from coming between you and your customers You invested in on-line terminals to assure prompt, accurate service. Now they are causing your custom- ers to think back to the good old days. And it's all because of a problem you can easily avoid. Static — actually, static charge — can cause a terminal to erase, send erroneous data or alter memory. It can strike at any time. Even in summer, when your air conditioner dries the air. Even on vinyl floors, where employees wear foam-soled shoes. Fortunately, the solution is easy and effective. 3M Static Control Floor Mats create an inexpensive island of protec- tion" around your sensitive point-of- sale equipment. By harmlessly draining static charge from your clerks and others, they help improve your service to customers while keeping equipment service costs down. Call us for more information on 3M Static Control Floor Mats. Call toll-free. 1-800-328-1300 (In Minnesota, call collect 612-736-9625.) Ask for the Data Recording Products Division 3M Hears You.. Listing 1 continued: 00740 00750 00760 00770 007S0 00790 00S00 00810 00820 00830 00840 00850 00360 00870 00880 00890 00900 00910 00920 00930 00940 00950 00950 00970 00980 00990 1 000 010.10 01020 1 030 01040 01050 01060 01070 01080 U1090 01100 01110 01120 01130 01140 01150 01160 01170 01180 01190 01200 01210 01220 01230 01240 01250 01250 01270 01280 01290 01300 01310 01320 01330 01340 01350 01360 01370 01 380 01390 01400 01410 01420 01430 01440 01450 01460 01470 LPS LD (401 AH), LD A, E LD CHL),E PUSH BC LD BC, 600 CALL 0060H POP BC LD A, CBC.) AND E RET Z ; STORE NEW VALUE ICHAR, WPS SAVED IN ;ADD IT TO MEMORY ;SAVE COPY IN STACK ! SHORT DELAY COUNT !ROM DEC. BC TO SNOW RESTORE 'BC 5 TRANSFER TO 'A' ; CHECK OUR COPY ; RETURN IF ZERO >f : # if: * : +•. * Jf : Jf : Jf : + Jf : Jf : Jf: Jf I Jf : :f : sf I * :f : * jf : jf: Jf= Jf . Jf : * :+: Jf : Jf : Jf : + Jf: Jf : +: * + Jf : :+: Jf : J* * I Jf : :+: sf : :+: + * :+: * sf 1 +: * a* Jf : Jf : Hk ** KEY BEEP IS HERE BUT 'NOT' BEING USED ** sf : jf : :+: jf ! >f I * * * »•* ♦ '+ : + + : <• : + >f: + * * f: +. sf : :f : sf : sf : :+: :f : jf : >f : rf : * jf : :ft rf : sf : sf : sf : :f: sf ? + : jf : :f I :f I :f i + ! :f ! :+: sf : sf : :f : sf | :f : ** FOLLOWING JUMP HAS TO BE USED BEEP OR NOT* ■ ! ** :f: sfe jf : sf : sf: jf : sf : sf : :f : sf : jf : jf: jf : sf: sf : sf : jf : Jf: * Jf I sf: Jf: >f I + Jf : :f : 4 1 * * :f I :+: * *N * ■¥ + * * :f : + * :f : * + * + : :f : * * * + :f I Jf ! * * :f I PUSH BC PUSH HL PUSH AF LD Bi 40H LD A, C403DH) AND 0FDH LD H, A OR 02H LD L, A LD A, L OUT (0FFH>, A LD A, H OUT <0FFH), A PUSH BC LD B, 40H DJNZ LP7 POP BC DJNZ LP6 POP AF POP HL POP BC JP 03FBH ;RQW COUNTER IN ROM START sf : :f : :+: sf : sf : sf : :f : sf: sf I sf: sf : »fi :f : sf : sf : sf: + •+, sf : sf: sf: & sf : :f t :fi :f: >f I :f : sf- +: :f: :f : sf : >f t sf: sf : sf : * :f : sf : sf : :f : >f : >f : :f : sf : sf : sf : :f: :f : sf : sf : sf: sf( :f : sf : ** TO USE JUST 7 ZX' AND CURSOR ROUTINE ** mm YOU HAVE TO PUT A 'HOOK' IN 40IEH AS FOLLOWS mm ■#. * >H sf: ^: sf : sf: :f : sf : + :f : sf : sf : *#£ :+: sf : sf : ;f: Ifc >f: jf I a#e :f j sf ; sf : sf : sf : :f: If : sf : :f : * : sf : sf : sf : >f : sf : sf : :* sf: :f= sf : :f ! :f : Sf: :f I sf : sf : :f: |f( sf : jfe sf : sf : :f : :f : 0ef00h ; start someplace! * hl, begin ;get address # c401eh:),hl ;store in video block * 402DH 5 1A19H FOR 'BASIC 7 p Jf: >f: Jf: * >f : ^: sf: :f : >(•: sf: + : sf. >f : sf : >f : :f : + jf : >f : * >f : >f: sf : +: :f : +: :^^ jf: >f : jf: jf: sf : 9ft * * jf : >f : sf : + : jf : +: :f: >f : jf< >f : jf : jf: :f : >f : :f : Sf : jf : jf : jf : *c jf : jf : :f : * jf : jf : :f : >f : :f: :f : •+: :f: jf : >f: :f: :f : >f : jf : jf \ -ft jf : jf : jf : :f : Jfl jf : >f : jf: mm 'ZX' LINEPRINT STARTS HERE CAN BE CHANGED TO ** mm ANY VALUE THE USER PLEASES AS LONG AS THE RIGHT mm mm ROW AND KEY VALUE ARE USED TO CHECK FOR IT mm sf : jf: :f :+::+:+: :f: :f: jf: jf: + :f; +:*^ ORG LD LD JP BEGIN LOOP LOOP1 EX EXX LD CP JR LD LD LD CALL LD LD LD CP AF, AF' A, (380BH) 05H NZ,OUT HL, 3C00H E, 10H C40H TEST A, (HL) C37E8H), A A, C3S40H) 80H SWAP REGISTERS ALL OF THEM ! = 7 ZX' ROW - 7 ZX 7 PRESSED ?? NO - EXIT FAST THEN POINT TO VIDEO ■ 16 VIDEO LINES = 64 CHRS. /LINE CHECK ON PRINTER GET FIRST CHARACTER OUTPUT TO PRINTER PORT SPACEBAR ROW ■ SPACEBAR PRESSED'? Listing 1 continued on page 386 384 April 1982 © BYTE Publications Inc H There's great business ahead! And here is THE DATA BASE to get you there. Meet GBS...the most complete, most powerful relational database management system available. It was designed to go beyond the capabilities of ordinary DBM systems. And it does. Where others may possibly be state- of-the-art...GBS, our General Business System, is ahead-of-the-art! Because it is relational, GBS is far more valuable to you and your busi- ness. It has the capability to access an almost unlimited amount of data from a variety of files, then combine that data and display or print it in a format that you specify. Relational, Efficient & Automatic GBS can automatically search for, locate, and interrelate information from many files. For example, on each order entry it can automatically decrement inventory; automatically post the data to your Accounts Receivable and automatically update your General Ledger. You don't have to spend countless hours making redundant entires, with the chance for numerous errors. GBS' interfile relationships and adjustments save you considerable time, and thus many hours of high-cost labor. Most other business programs are limited single file systems, whereas GBS allows you to work with 3 different files at the same time. All Indexes are updated automatically. What's more, a large GBS data file can extend over 4 different disk drives.. .not merely one. Mo other data base system has the power and flexibility of GBS! Circle 347 on inquiry card. A program generator, par excellence Included as a part of GBS is a very powerful applications development tool, called QUICK GEN. Basically, this function allows almost anyone - even those unsophisticated about computers -- to generate useful business programs. Think of the efficiency you gain when anyone on your staff can quickly generate a needed program to solve a particular problem! But, GBS versatility doesn't stop there. GBS is also ... ...a Fully Programmable system... ... which allows you, or those with deeper computer interest, to create almost any business application program, such as accounts payable/ receivable ... payroll ... general ledger ... order entry ... mailing lists ... personnel files ... cost accounting ... real estate listings ... time/ expense management, and many more. And each one will be a personalized program ... individualized to the specific requirements of your firm! Start using GBS now You can. Because GBS is up and running on most popular CP/M* based computers, like those made by Apple, Tandy, Xerox, Sharp, NEC, Hewlett Packard, Toshiba, Osborne, Televideo, Vector, Altos and more. You can. Because GBS docu- mentation is written in a friendly, free- flowing, style...and it leads you by the hand with plenty of tutorials and easily understandable examples. And, the entire documentation is typeset for ease of reading. You can. Because GBS is fully supported by QUALITY SOFTWARE, So, if you ever have a question, or need assistance, simply contact QUALITY SOFTWARE and our professional support people will be happy to help. You can. Because we offer a special 30-Day Money Back Guarantee. Order your edition of GBS at $700 (on disk, with complete professional documentation) and try GBS in your own business environment. If GBS isn't all we say it is, and more, simply return it within 30 days for a full refund. This offer is for a limited time only, so please act immediately. Call Today There's great business ahead. And GBS is the relational data base management system which can help you control your information and data quickly, efficiently and effectively. Call us today for additional information or to take advantage of our special 30-Day Money Back Guarantee. GBS - it's the best business decision you can make, for today and the future. QUALITY SOFTWARE 6660 Reseda Blvd., Suite 107 Reseda, CA 91335 (21 3) 344-6599 *CP/M is a registered trademark of Digital Research. BYTE April 1982 385 TEST OUT! OUT Listing 1 continued: 01 480 01490 01500 01510 01520 01530 01540 01550 015G0 01570 01580 01590 01600 01610 01620 01630 01640 01650 01660 01670 01680 01690 01700 01710 01720 01730 01740 01750 01760 01770 01780 01790 01800 01810 01820 01S30 01840 01850 01860 01870 01880 01890 01900 01905 01910 JR INC DEC JR CALL LD LD DEC JR JR LD CP JR RET COLL LD LD EX EXX Z, OUT1 HL C NZ,LOOPl TEST ft, 0DH (37E8H),fi E NZ,LOOP OUT A, (37ESH) 3FH NZ,TEST TEST ft, 0DH (37E3H),ft flF,ftF' ;YES - EXIT ;ftDD NEXT CHARACTER ; MINUS (1) CHARACTER ;LOOP FOR 64 CHARACTERS SPRINTER BUSY? ; CARRIAGE RETURN ;do it 1 5next line - please ?all 16 lines? ;go if all done ; check byte at printer 163 dec. = printer busy ;loop until ready ; return to caller ; check on printer ' carriage return ?do it on printer! 5 restore registers ?all of them I** CURSOR ROUTINE STARTS HERE AND ** ?** CAN BE USED SEPERATELY ALSO — ** CURSOR CALL PUSH PUSH LD LD CP JR 0458H AF DE DE, (4020H) A, CDE) 5FH NZ, EXIT ;CALL VIDEO ROM DRIVER !SAVE 'AF' ;SAVE ' DE' SCURSOR POSITION ?PUT CHARACTER IN 'A' ?« NORMAL CURSOR ;NOT NORMAL - GO S** MEMORY ADDRESS 16409 DECIMAL IS USED TO — ** I** STORE THE CURSOR CHARACTER OF USER'S CHOICE ** ;** POKE 16409 WITH ?ANY CHARACTER TO SUIT ;YOUR NEEDS FOR A CURSOR 5EXAMPLE: POKE 16409,176 ; RETURN TO PROGRAM EXIT LD ft, (16409) LD i A POP DE POP AF RET NOP END START ;AUTO STARTS WITH *? / Text continued from page 380: Subtracting the starting address (in decimal) from the ending address pro- vides the byte count. Subtracting the byte count from the top of memory (in decimal) indicates where the pro- gram would have to start to load to the top of memory. Since it is neces- sary to protect only that portion of memory into which MOD III is load- ed, this figure also represents the memory -size value that must be entered upon power-up. The starting address in listing 1 is for a 48K-byte system. To calculate the starting address for a 16K- or 32K-byte system, subtract 169 (the minimum byte count) from 32,767 (16K) or 49,151 (32K) as applicable. Convert the result to the equivalent hexadecimal notation and use it for the ORG (origin) address in line 130. The foregoing is applicable to the program as written. If you want to add additional lines or include the key-beep feature, be aware that doing so will increase the program byte count. The memory space occupied by the program must be increased by changing the starting address accord- ingly. Very "tight"' code was used in writ- ing the MOD III source code to keep memory overhead low. Read-only memory (ROM) routines were used frequently, although not many ROM calls are evident. The approach to im- I Industrial marketing problems? Regardless of what marketplace you are staking out, its position or size, we can help you draw a precise circle around it. Why? Because as the leading business/technical /professional publish- ing company, we probably already know your market and can apply our expertise to your research needs. Give us a call, Phone Ann Graham- Hannon at 212-997-6401 or write her as Director, Marketing Research, McGraw- Hill Research, 1221 Avenue of the Americas, New York, NY 10020. Call McGraw-Hill Research m If it's a marketing research problem, we probably pioneered the solution. 386 April 1982 © BYTE Publications Inc The 16 bit operating system designed specifically for business micro-computing. Application software?— it's here, NOW! OASIS -16 *: the operating system designed for business. Not just a hobby or development system rewritten for business use, it is the natural evolution of OASIS**: the multi-user system with a world-wide reputation as the standard for those who take business seriously. And here's more good news : there's no waiting for application software because what now runs on OASIS is upward compatible to run on 0ASIS-16. That means plenty of proven software, available immediately. OASIS-16 puts it all in one package . For manufacturers: one source for oper- ating systems, languages, tools; custom implementation to maximize hardware potential; international support & training; flexible licensing agreements. For software developers: complete portability keeps application software machine independent; integrated tooi set makes development easier, faster. For end-users: user-friendliness; data security; portability simplifies system expansion; plus an extensive applica- tion software library Computing professionals have long told us ' OASIS makes micros run like minis ' —with OASIS-16, it's truer than ever. And that's strictly good business . *For 8086 : 68000, Z8000, LSI-11, & others. **For Z80. THE OASIS-16 PACKAGE CONTAINS: Operating System, EXEC JCL Language; Editor; Script Output Text Formatter; Assembler; Linkage Editor; Diagnostic & Conversion Utilities; BASIC Interpreter & Compiler; 'C Compiler. FEATURES: File & Automatic Record Locking; Logon, Password & Privilege Level; User Accounting; Re-Entrant BASIC Interpreter & Compiler; ISAM, Keyed, Direct & Sequential Files; and more, Plus some of the best, most extensive documentation in the industry. OPTIONS: COBOL; PASCAL; FORTRAN; RDBMS; 2780/3780 Bisync; Networking; and others. PHASE ONE SYSTEMS, INC. 7700 Edgewater Drive, Suite 830 Oakland, CA 94621-3051 Telephone 415/562-8085 TWX 910-366-7139 I'm serious about my business — please send me quick: □ OASIS-16 Manual, $75 □ OASIS Manual, $60 □ Free Application Software Directory and put me on your mailing list. {Add $3 for shipping; California residents add sales tax ) Name St. (No Box#)_ City ___ □ Check enclosed D VISA □ Mastercharge Card Mn State__ Zip_ □ UPS COD. Exp. date^ Signature. STRICTLY BUSINESS Circle 329 on inquiry card. BYTE April 1982 387 Circle 97 on inquiry card. TF* 1JI# dT% JTI JW^ M tkM #^ If you like to communicate with others, the CompuServe Information Service is your most effective vehicle. Why? Because we have the largest customer base of any videotex system in North America. And we have hundreds of new subscribers each week. "Talk" to other CompuServe subscribers via CB simulation (it's the most popular offering on our network). Send E-mail, use the electronic bulletin board and exchange information with computer manufacturers, Special Interest Groups and publishers. Play a variety of networking games with your own group or complete strangers from New York to Chicago to LA. Ask for a demonstration at a Radio Shack" Computer Center. Videotex software is available for various brands of personal computers. CompuServe Information Service, 5000 Arlington Centre Blvd., Columbus, Ohio 43220. (614) 457-8650. CompuServe UN EMPLOYMENT OPPORTUNITIES 1 DP OPPORTUNITIES | 1 1 Martin Marietta Aerospace, NASA's designated Contractor for the Space Shuttle Ex- ternal Tank Program has the following immediate opportunities at their Michoud Assembly Facility in suburban East New Orleans: Business Applications Programmers/ | Project Lead Experienced In: •Engineering •Manufacturing *Shop Floor Control •Scheduling • Inventory •Purchasing UNI VAC DMS 1100 Data Base Or Other CODASYL Data Base Experience Utilizing The Data Manipulation Language With COBOL Knowledge Of: •DDL -SDDL •TIP/CMS -DPS 1100 •DDS 1100 Specialist •Network Controllers •Operations Research All interested and qualified candidates are urged to send their resume, complete with salary history and background to: Martin Marietta Aerospace, Dept. B, P.O. Box 29304, New Orleans, Louisiana 70189, Attn: Personnel Department. We are an equal opportunity employer, m/f/h. ATXl/^TY/V MJ%99tE TTJA plementing the key-repeat feature was to intercept the ROM keyboard buffer and thus minimize the calls re- quired for this feature. Hook Lines Although the program actually starts at the ORG address, the first 20 bytes are used as hook lines that establish conditions for program operation. These lines are used only once each time the program is loaded; therefore, they can be written over after the program is executed. The main program starts at the key-repeat module. This is where memory size must be set. To calculate the memory-size protect number, sub- tract 21 from the decimal equivalent of the line 130 starting address (the additional byte is used as a safety fac- tor). Key Beep A modular approach was used in developing MOD III. Each of the three main features of the program was originally written as a stand- alone routine. Each routine was de- bugged, tested, and proven workable before the three were combined into a single program. Note that although the key-beep module has been in- cluded in the source listing, it is not a part of the assembled program. (This is due to the use of semicolons, which cause the assembler to treat the pro- gram lines as remarks.) The key-beep feature introduced a few disadvantages. It is necessary to plug the AUXiliary cord into an amplifier to get an audible beep; how- ever, this activates the cassette tape recorder (CTR) OUT line. (I dis- covered this when loading a program. With key beep active, the CTR started when the PLAY button was pressed.) This isn't a problem as long as you are aware of it. I use a Radio Shack miniamplifier as a sound source. Beep volume is controlled by the amplifier volume control. At a low level, the beep is barely discernible, reminding me of a "squeaky" key. At a higher level, a sharp, short beep is heard as each key is depressed. But I found that the beep became annoying during long ses- sions at the keyboard. 388 April 1982 © BYTE Publications Inc EPSON PRINTERS & ACCESSORIES Common Features of the MX80, MX80FT & MX100 Printers 80 characters per second Replaceable print head by user User proa/amable from BASIC Bi-directional logic seeking printhead 96 ASCII characters Programable tabs (vert./horz.) Cartridge ribbons Self-tesl mode Tractor/pin teed paper flow Extreme reliability 12 type fonts under software control 9x9 & 9x18 matrix Programable form feeds Compressed/expanded letters Parallel interface standard Double strike & emphasized modes MX80 The Printer that started it all. All of the above features plus extreme ease of use. CompleteTRSSO block graphics set as well as user selectable international symbols. Gives correspondence quality printing in several user selectable modes. Dip switch pins may be set for dedicated applications. Complete forms programability from BASIC software. MX80FT All the features of the MX80 but with FRICTION feed as well for the use of single sheets of paper or roll paper An exceptional buy for the user needing the single sheet capability in the compressed mode 132 characters can be printed across the width of a page which means it can be used for any printouts that normally need a 15 inch wide printer. MX 100 An exceptional printer with a extra quiet printhead and extra heavy duty construction for the intense use of a business environment. Does not have the TRS80 graphic blocks but comes standard with Bit-Image graphics which allow the user control of individual dots for designing specialized graphs, symbols, etc. A best buy for business use. MX70. .For the budget minded a excellent entry level printer. It has most all of the features mentioned above including Bit-Image graphics in place of the TRS80 graphic blocks set. The Printer is unidirectional only. Expandable text can be printed but not compressed. Only single density printings is supported on the MX70, An inexpensive heavy duty printer. $CALL for BEST prices on Epson Printers All Printers & accessories in STOCK now!!! If you buy your EPSON somewhere else you'll probably pay too much! EPSON ACCESSORIES, INTERFACES & CABLES GRAFTRAX 80 option (bit-image & italics) .$79 CABLE Model I interface & Model III $35* ■ ^ * $25 if purchased with printer jfflRl i^^L Mm $ H CABLE & INTERFACE to Model I Keyboard $85 »L M ^ M\ 1 f APPLE interface & cable $89 ^^ ■ _ ^mM § 1 PET IEEE interface & cable (Pet) $79 %±M ^^*V ^^% M^m ha SERIAL RS232 unbuffered int.card $65 ^T ^^ ^^ ^^ SERIAL RS232 2k buffered int.card $149 Epson to Color Computer card/cable $59 800-433-51 84 All RIBBONS and CARTRIDGES in Stock OVV-HOO-3 OH Radio Shack LINE PRINTERS Daisy Wheel II $1695 Line Printer V $1580 Line Printer VI $988 Line Printer VII $325 Line Printer VIII $699 TEXAS COMPUTER SYSTEMS Offers Lowest Prices on Model II 64K The best buy for small business needs and yet completely expandable as your business grows. Easy to use for the beginning operator. We have in STOCK all accessories and disk expansions as well as printers and software. IMPORTANT: We also have CP/M for the Model II plus a large amount of support software. All of these items at our fabulous DISCOUNT prices. We ship from DFW by air and fully insured for FAST safe delivery. HARD DISK SUPPORT FOR THE MODEL II...NOW! 5. 10 or 20 Megabytes (up to 80 Megabytes) for the Model II. Full CP/M support. Also full support for TRsDOS and alt TRSDOS software. Multiple computers (multi-user) can be con- nected to these hard disk systems and can share and access common data bases under both CP/M and TRSDOS. The same common data base can even be accessed simultaneously by several users. We use top of the line CORVUS Hard Disk Drives which have a proven tracfc record and have outsold all of their competitors combined in the microcomputer market. Model I and III are also supported by these Hard Disk Systems. SCall for our LOW prices. COLOR COMPUTERS Orginal mfg. warranty on these items: 4K Level 1 $308 16K Level 1 $439 16K Extended Basic $459 32K Extended Basic $569 Color Disk 0...$499 Disk 1...S349 TCS 180 day Limited warranty on TCS items. 16K Level 1.. $369 16K Extended Basic $439 32K Extended Basic $499 32K Upgrade Kit (TCS) $79 EPSON/tOLOR lnt.& cable $59 TRS80 MODEL III COMPUTER SYSTEMS The following with Radio Shack Warranty: _ u . .... .. _-- , , ,,,.,«, *n«r The following with quality TCS memory & our Model III 16k $825 own 180 day limited warranty: Model III 32k $979 Model III 32K $909 Model III 48k $1089 Model III 48K $969 Model III 48k 2 Drives RS232.$2069 CUSTOM SOFTWARE FROM TCS Completely Integrated BINARY SEARCH TREE programs now available. This series of programs fully implements the B-TREE structures including INSERTION, DELETION, EDITING & TRAVERSAL. No more sorting or long data file searches and yet files can be larger than memory. Duplicate keys are fully supported. Files can be retrieved in sorted order via B- TREE Traversal. Each of the programs come with fully commented source code so that you can use the modules in your own programming. A Screen oriented Input routine is also included in each module. The following B-TREE programs are now available and each includes all of the mentioned modules and full documentation: B-TREE Library (organize your horn* library kayad by author) $39.95 B-TREE Vidao (organize your video cassette library, prints labels, ate) $39.95 B-TREE Mailing List (kayad by name or zip. label printlng.etc) $49.95 EPSON PACK A Utility Soft- ware package for MX80 & 80FT. MX80/CMD will send all printer commands from DOS. BIGLETT/BAS prints lame Graphic Letters. EPSON/SUB merges with BASIC pro- grams allowing 2 letter mneumonic commands to be sent to printer. JKL Patchs allow JKL in NEWDOS 80 1.0 & NEWDOS 2.1 to send graphics properly. DEMO/BAS tutorial program of use of printer.LABEL/BAS custom label making program with graphics. DEF- STATE/SUB allows one word BASIC com- mands for centered titles, titles with borders, etc. A great program package for EPSON fans SPECIAL DEAL: $24.95 with printer $34.95 seperately. Specify Model 1 or III. disk only EPSON PACK 2 - GRAFTRAX version for MX80, 80FT & MX100. This package includes updated versions of modules in original Epson Pack. A screen oriented BIT IMAGE GRAPHICS generator util- ty is provided Create your special characters, symbols, etc. directly on your monitor and tnen send to printer. Printout in- cludes code to generate graphics and will save needed code as BASIC program line to disk. Then MERGE these into your BASIC pro gram. Also demo programs showing use of it-Image graphics. Full documentation. INTRO SPECIAL: $24.95 with printer or GRAFTRAX. $34.95 separately. $7.50 for update of old Epson Pack ZAP3 - Direct read/write access to any TRSDOS 1.2 or 1.3 sector. Disable Passwords & access levels. Self prompting. Modify any sector in HEX or ASCII. Includes many patches to TRSDOS 1.2 & 1.3. Also COPYIT to allow backups of SCRIPSIT, VISICALC, etc. Just.. ..$24.95 SDIR - Super directory manipulation for TRSDOS 1.2 or 1.3. Alpha 4 column directory & free space. Display a range of programs by extension. Change name and date. Generate report of location of any program on diskette. Just ..$14.95 SPECIAL DEAL: Buy ZAP3 & SDIR together for .... $29.95 MODEL III DISK EXPANSION KITS We use the highest quality fiberglass Our DISK DRIVES are made by Tandon the CONTROLLER BOARDS with double sided same company that makes the drives used by glass eooxy board and goldplated contacts in Radio Shack These drives are 40 track. our TCS systems. The finest switching double density, 5 millisecond stepping rate POWER supply available is also provided, and are fully burned in for 48 hours. These The aluminum MOUNTING HARDWARE drives have the same specifications as the has slotted holes for easy installation of the drives used by Radio Shack No soldering or drives and includes all the power and data modifications to existing circuitry is cables necessary to install the controller, necessary The following kits are available: drives and power supply KIT 1 Controller, Power Supply & Mounting Hardware $379 KIT 2 Controller, Power Supply, Hardware & 1 Disk Drive $595 KIT 3 Controller, Power Supply, Hardware & 2 Disk Drives... $819 KIT 4 One Tandon Disk Drive (bare drive only).. $219 KIT 5 16K of High Quality TCS Memory chips $49.95 KIT 6 32k of High Quality TCS Memory chips $79.95 MODEL III 48K 2 DISK DRIVES KIT.. ..$1753 Yes, you read it right A complete 48k 2 Disk Drive Model III computer system for just $1753. Here's what you get: one TRS80 Model III 16k Computer in factory carton, one CONTROLLER, POWER SUPPLY & HARDWARE kit (kit 1). two Tandon Disk Drives and 32K of TCS Memory. You also receive several important extras that make this a complete super kit. These extras include a complete illustrated instruction and trouble shooting manual, a TRSDOS 1 .3 operating system and manual and a special diagnostic Diskette for testing the unit after you have put it together. The only tool necessary - a screwdriver. EVERYTHING is included in this kit and the price is right ..$1753 MODEL III 48k 2 DISK DRIVES ... $1895 Above KIT fully assembled, with 48 hour burn-in test & 180 day TCS Limited Warranty!! DEALER INQUIRIES ARE INVITED ON THE ABOVE TCS KITS CASIO ELECTRONIC ORGANS have arrived!!! The fantasic CASIO Electronic Organs are here in force. Fully equal to any $2000 traditional Organ with dozens of exciting NEW features not seen on other musical instruments: CASITONE CT— 403 (25 Instrumental 6 rythms,chord m«mory,etc.) $519 CASITONE CT-701 (programable barcode read«r,51 key»,etc.,etc.) $835 For fast, efficient service. Heart Of we can air freight from Dallas TEXAS COMPUTER SYSTEMS P.O. Box 1327 Arlington, Texas 76004-1327 VV Toll Free Number 800 433-5184 Texas Residents 817 274-5625 Payment: Money order, cashiers or certified check. Prices above reflect 3% cash Discount Call for Visa/MC card prices. Prices subject to change at any time No Tax out-of-state. Texans add 5%. Many items shipped FREE. Call for quote. Circle 413 on inquiry card. BYTE April 1982 389 Source Code Modules The source code listing has been structured to allow use of any one or a combination of the modules. For ex- ample, the video-line-print module (lines 1210 through 1580) can be keyed in as a stand-alone program. In doing so, appropriate starting and ending addresses must be added to the routine. Lines 130, 170, 180, 190, and 260 will provide the start and en- try points. The following lines must be added to the "ZX" routine to com- plete a stand-alone listing: 1590 JP 0458H 1600 END START ;GOTO NORMAL VIDEO IN ROM ;EQUALS TRANSFER The key-beep routine has been in- cluded in the source-code listing for readers who wish to try it. To include the routine when keying in the code, the remark character (;) must be left out. Otherwise, it is not necessary to enter lines 760 through 1010. The program starting address must be changed to a lower value if the key-beep routine is included. As the program byte count has not been cal- culated with key beep included, this must be done by picking an arbitrary starting address, assembling the pro- gram, and then calculating total byte count. Once the byte count is deter- mined, the starting address can be changed accordingly . MOD III BASIC Version A BASIC language version of MOD III is provided in listing 2 for those who do not have an editor/ assembler. The program listing is somewhat shorter than the assembly- language version because it does not include key beep. As written, this program is self- checking for the correct response to RAM-size input (see lines 40 through 100). An INKEYS routine (see lines 50, 60, and 90) is used for the input to prevent scrolling. If you enter two numbers in response to the RAM-size prompt, the program automatically branches to line 70 to check the input value. It is not necessary to press the ENTER key to conclude the input. Line 70 checks the validity of the input value. If the A-f-B input is valid (i.e., 16, 32, or 48), program flow is directed to the corresponding lines. An invalid entry will erase the numbers that were typed after the RAM-size prompt and set up the IN- KEYS routine for a new input cycle. Listing 2: The BASIC listing for MOD III. The disk BASIC commands have been disabled; remove the apostrophes to enable these lines. * M0D3 * BASIC VERSION S. 1 BY J_ ROCKE 10 CLS: PRINT: PRINT TAB< 12) "BASIC PROGRAM TO POKE " ;CHR*<34) 20 PRINT:PRINT TABC 11 ) " INTO MEMORY USING DATA STATEMENTS" 30 PRINT:PRINT TABCI9)"BY: JOE W. ROCKE" : PRINT : PRINT 'MOD III" ?CHR*(34) 43) THEN 150 160 40 PRINT TAB(3>" (ENTER) THE SIZE OF RAM CIS, 2 50 GOSUB90:A=VAL(A$) :PRINT3565, A; :A=A*10 60 GOSUB90:B=VAL :PRINTa565, A+B 70 IF (A+B) =16 THEN 110 ELSE IF (A+B) =32 THEN PRINTSJ565, " 80 GOTO 50 90 A*=INKEY*:IFA« j\-r\ ±r\ A lrxi IT* svstem memory by adding U y tw UU yULLL just one card, freeing up KM |-toirQO"nPll additional functions. C ILJL I L KZLOVJL LCiL get the Qua dram V AlTlllil lt"P>l* Deluxe board with up to 192K VVJL L LplAtwL. ram, a clock /calendar, parall Now! L^wlvWL* RAM, a clock /calendar, parallel l/xv A if interface and serial adapter. All on IUW; one board! Full-line IBM add-ons with off-the-shelf availability. Expanded memory . . . additional capabilities. .. and unbeatable prices. Quad- ram's ready now to help your IBM bite off more. (We have been shipping off-the-shelf since late 1981.) roclucts i «64K RAM .nst^ii ■\n\ ' -,T $59S" Serial RS-. s adapte single port adapter •nsionkit ■+60 Clock/calendar board (with diskette) Parallel ir md cable $159 $159 Available soon: Non-Volatile RAM; Game I/O; Parallel/Game I/O Com- bination; 192K Memory/Clock Combination; .ROM Board; Expansion Chassis; Disk-I/O Expansion Chassis; 5, 10, 20 meg Hard Disk. For further information and the name of your nearest deafer, call (404) 923-6666 or fill in this coupon and mail to: Quadram Corporation, 4357 Park Drive, Norcross, Georgia 30093, Name Company Title Address City State Zip Circle 344 on inquiry card. uircie 279 on inquiry card. FOR TRS-80 MODEL I OR III AND SOON FOR THE NEW IBM PERSONAL COMPUTER! • MORE SPEED 10-20 times faster than Level !l BASIC. • MORE ROOM Very compact compiled code plus VIRTUAL MEMORY makes your RAM act larger. Variable number of block buffers. 3l-char.-untque word- names use only 4 bytes In header! • MORE INSTRUCTIONS Add YOUR commands to its 79-STANDARD-plus instruction set! Far more complete than most Forths: single & double precision, arrays, string-handling, clock, more. • MORE EASE Excellent full-screen Editor, structured & modular programming Word search utility THE NOTEPAD letter writer Optimized for your TRS-80 or IBM with keyboard repeats, upper/lower case display driver, full ASCII, single- & double-width graphics, etc. • MORE POWER Forth operating system Interpreter AND compiler 8080 or 8088 Assembler (Z80 Assembler also available for TRS-80) Intermix 35- to 80-track disk drives Model III and IBM can read, write and run each other's and Model I diskettes! 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All on one diskette (requires MMSFORTH V2.0, 1 drive & 32K RAM) . $39.95* FORTHCOM: communications package provides RS-232 driver, dumb terminal mode, transfer of FORTH blocks, and host mode to operate a remote TRS-80 (requires MMSFORTH V2.0, 1 drive & 32K RAM) $39.95* THE DATAHANDLER V1.2: a very sophisticated data- base management system operable by non-pro- grammers (requires MMSFORTH V2.0, 1 drive & 32K RAM) $59.95* MMSFORTH GAMES DISKETTE: real-time graphics &. board games w/source code. 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Get MMSFORTH products from your computer dealer or MILLER MICROCOMPUTER SERVICES (B4) 61 Lake Shore Road, Natick, MA 01760 (617)653-6136 Listing 2 continued: 360 ' **:********* 32K - ROM III DATA #******»§«*** 370 '** MEMORY SIZE? 48931 380 POKE 16526, 77=POKE 16527, 191 :' NORMAL BASIC 390 T DEFUSR1=&-HBF4D:'DISK BASIC 400 FOR Z8=-16563 TO-16385" READ Z9:P0KE ZS, Z3:NEXT ZS 410 A=USRC0) :' NORMAL BASIC 420 'PRINT USRKB) :'DISK BASIC 430 END 440 DATA 33, 97, 191, 34, 22, 64, 33, 170, 191,34, 30,64, 62, 143,50 450 DATA 25,64,195,25,26,33,54,64,1,1,56,22,0,10,95,163,32 460 DATA 26,119,20,44,203,1,121,214,128,32,241,126,6,7,45 470 DATA 134,16,252,254,0,62,0,192,50,26,64,201,166,40,16 480 DATA 58,26,64,60,50,26,64,254,255,32,217,61,50,26,64 430 DATA 123, 115, 197, 1,88,2,205,96,0, 193, 10, 163,200, 195,251 500 DATA 3, Q, 217, 58, 8, 56, 254, 5, 32, 54, 33, 0, 60, 30, 16, 14, 64 510 DATA 205, 217, 191 , 126, 50, 232, 55, 58, 64, 56, 254, 128, 40, 25 520 DATA 35,13,32,238,205,217,191,62,13,50,232,55,29,32 530 DATA 225,24,16,58,232,55,254,63,32,249,201,205,217,191 540 DATA 62,13,50,232,55,8,217,205,88,4,245,213,237,91,32 550 DATA 64,25,254,95,32,4,58,25,64,18,209,241,201 5B0 DELETE 10-560 570 ■ *+:+**+++*+::+: 4BK - ROM III DATA **■.+****+**+ 580 '** MEMORY SIZE? 65375 590 POKE 16526, 77: POKE 16527, 255: » NORMAL BASIC 600 'DEFUSR1=&-HFF4D:'DISK BASIC 610 FOR Z3=-179 TO-1 : READ Z9:P0KE Z8, Z9:NEXT Z8 620 A=USRC0> : f NORMAL BASIC 630 'PRINT USR1C0) :' DISK BASIC 640 END 650 DATA 33, 97, 255, 34, 22, 64, 33, 170, 255, 34, 30, 64, 62, 143, 50 660 DATA 25, 64, 195, 25, 26, 33, 54, 64, 1 , 1 , 56, 22, 0, 10, 95, 163, 32 670 DATA 26,119,20,44,203,1,121,214,128,32,241,126,6,7,45 680 DATA 134,16,252,254,0,62,0,192,50,26,64,201,166,40,16 690 DATA 58,26,64,60,50,26,64,254,255,32,217,61,50,26,64 700 DATA 123, 115, 197, 1,88, 2, 205,96,0, 193, 10, 163,200, 195, 251 710 DATA 3, 8, 217, 58, 8, 56, 254, 5, 32, 54, 33, 0, 60, 30, 16, 14, 64 720 DATA 205,217,255,126,50,232,55,58,64,56,254,128,40,25 730 DATA 35, 13, 32, 238, 205, 217, 255, 62, 13, 50, 232, 55, 29, 32 740 DATA 225,24,16,58,232,55,254,63,32,249,201,205,217,255 750 DATA 62,13,50,232,55,8,217,205,88,4,245,213,237,31,32 760 DATA 64,26,254,95,32,4,58,25,64,18,209,241,201 This safeguard prevents program ex- ecution until a correct RAM size has been input. The check for RAM size is a vital feature of the BASIC program. The listing contains three data groups, and the computer will always read the first data group unless directed elsewhere. Without lines 40 through 70, the 16K-byte data would be POKEd to memory regardless of memory size. If this were the case in a 32K- or 48K-byte system, you would have only the equivalent of a 16K-byte system available for use. Upon branching to a data group corresponding to the RAM size, the normal BASIC vectors are POKEd to memory (lines 170, 380, and 590). Data corresponding to the machine code equivalent values are then READ and POKEd to memory (e.g., lines 190, and 230 through 350). Upon completion of the data READ /POKE operation, unnecessary portions of the program are deleted to conserve memory (see lines 350 and 560). This returns the computer to READY status. Entering a RUN com- mand will then activate the MOD III features. Keying in the BASIC Program If you shudder at the thought of keying in long, numerical data state- ments, take heart! The task is not as big as it may first appear if you are content with a program limited to one memory size only. In this case, the RAM-size input lines may be eliminated. Only the desired memory-size data group need be typed in for an in- dividualized RAM -size program. Using a 16K-byte RAM size as an ex- ample, only lines 150 through 340 need be keyed in. These lines will pro- vide the major MOD III features for a 16K-byte system. A word of caution is in order. If 392 April 1982 © BYTE Publications Inc THE QUASAR HHC TAKES COMPUTERS WHERE THEY'VE HEVER REEH REFORE. Your Personal, Portable Database. There were places you couldn't take a computer, or use one. Not any more. The Quasar HHC gives you the power of a computer anywhere you go. Planes, cars and boats, vacations, or wherever you may want to use it. The HHC can be your constant com- panion. So whatever data files or information you may need or want are always right at hand. The Quasar HHC gives you the full power of a 6502 microproces- sor. Programming in Microsoft Basic or the FORTH -like SNAP. And personal features like file creation, a calculator, and a real- 's^ time clock/secretary you can program to display re- minder messages. File data can be passed from one HHC to another or back and forth be- tween an HHC and another com- puter. Just connect both computers through the HHC RS-232C interface, or transmit/receive over telephone lines with the HHC acoustic coupler. There's never been : a computer like the Quasar HHC. And never a better way to make you more effective. For information on the Quasar HHC Hand -Held Computer, including how to become a dealer or distributor, write on your letterhead to Quasar Group Director HHC. Circle 454 on inquiry card. una ONE GREAT IDEA AFTER ANOTHER... QUASAR COMPANY, Division of Matsushita Electric Corporation of America, 9401 West Grand Avenue, Franklin Park, III. 60131. (312) 451-1200 ' MODIII' * PI SOFTWARE PROGRAM TO UPGRADE YOUR MODEL I * BLOCK CURSOR - VIDEO SCREEN PRINT - PUTO KEY REPEAT TRS-S0 MODEL III FEATURES IN ONE PROGRAM USING LESS THAN 300 BYTES OF MEMORY Figure 1: Sample output from the video-screen-print routine. If your printer can't han- dle graphics characters, the source code may have to be modified. you have never keyed in a machine code program via a BASIC READ/ POKE listing, note that the program should be saved prior to program ex- ecution. Therefore, be sure to save the BASIC program to cassette or disk after it is keyed in and before its execution. By doing so, you will have the source code (i.e., the BASIC pro- gram) in case the program bombs due to a typing error. The BASIC program has been writ- ten to include both normal and disk BASIC USR(O) routines. To use the program with disk BASIC, it will be necessary to delete the remark (') character used to mask the disk BASIC statements (see lines 180, 210, 390, 420, 600, and 630). The corres- ponding normal BASIC lines (e.g., 170 and 200) may either be deleted or edited to become remark statements. Using MOD III Memory size must be set before running either version of MOD III. The memory protect values for the BASIC version are provided in lines A "1? AIR" CREATURE A MULTI-USER MICROCOMPUTER SYSTEM FOR LESS THAN 3200 PER USER.* The Rair family of computers combines high performance features for a fraction of what you would expect to pay. 256K bytes, 8 serial ports, and a 1 80 CPS printer. That's enough ca- pability to get thejob done quickly and efficiently. And at an unbeatable price. * Based on typical 4 user installation. Plllilillll jillllllllllllllllllllilllll jpilllllipilllllHlllll I i i i t 2777 Orchard Run Rd. West Carrollton, Ohio 45449 (513)435-2283 160, 370, and 580 of listing 2. The assembly-language (system-load) ver- sion will automatically execute upon your entering a slash (/) at the *7 prompt after program loading is com- pleted. The MEMORY SIZE? prompt will be the first thing displayed on the video upon running the BASIC ver- sion. Upon your response to the prompt, the corresponding data are POKEd to memory. This is a very short run cycle that completes with a READY prompt. Entering RUN at this point results in program execu- tion. Appearance of the block cursor provides the only visual evidence that the program has been POKEd to memory. From this point on, the video-line-print and key-repeat features are also available. Either ver- sion of MOD III is completely unob- trusive once it is loaded to protected memory. Selectable Cursor The program, as written, provides a block cursor (ASCII 160). The cur- sor may be changed by POKing in any ASCII (American Standard Code for Information Interchange) char- acter of your choice. This is done by entering a POKE statement without a line number as follows: POKE 16409,nn where nn may be any ASCII number from 35 to 255. For example, POKing in an ASCII 42 will change the cursor to an asterisk (*). Video Screen Print Pressing the Z and X keys simul- taneously will output to the line printer whatever is displayed on the screen. The printout can be stopped short of a full display print by press- ing the space bar. Graphics characters on the video display will also be printed if the printer has graphics capability. The video-line-print fea- ture has been tested with both the Ep- son and Okidata printers which have graphics capability. Figure 1 is an ex- ample of a video-display printout. A nongraphics printer may print a period or other symbol in place of any graphics character displayed on 394 April 1982 © BYTE Publications Inc Circle 151 on inquiry card. MJPMAN! SHIP. WH^^^^^B|^^/ V ^^^^^^Wffi We opened our doors with two basic goals: To distribute as many software packages to as many dealers as possible. And to make money doing so. Our success on both counts is the result of hard work, a positive busi- ness attitude and a recognition that you, as a retailer, have a right to be treated fairly and honestly by your distributor. We're 1-up for three good reasons: 1. We always offer a wide selection of the latest and best microcom- puter software packages available anywhere. (Why should you have to hunt for what you need?) 2. Our dealer discounts start with quantities of 1. (Remember all those times you just wanted one or two to see how they'd sell?) 3. We don't play The BackOrder Game. (If we can't ship your order within 48 hours we'll let you know, instead of hanging you out to dry.) If there's anything else we can do for you, just let us know. Because we're 1-up and we intend to stay that way. Software Distributors, 9929 Jefferson Blvd., Culver City, CA 90230. Telex 4990032 BVHL, ATT: SOFT For our dealer info packaRe, call (213) 559-9330. Circle 376 on inquiry card. SOFTWARE DISTRIBUTORS We won't leave you holding the bag. BYTE April 1982 395 the video. The ZX routine may be modified to print a symbol of your choice with a minor change in the source-code listing. However, I haven't investigated this, and such a change must be left to your ingenuity. In attempting to do so, keep in mind that if the ASCII value displayed on the video is greater than 128, it is a graphics character. To modify the program, it would be necessary to load a substitute value less than 128 for a printer character output. Key Repeat Holding down any key results in an automatic key repeat. This feature has the advantage of providing a built-in key debounce via an approx- imate 25-millisecond time-delay loop. Holding down the space bar will automatically advance the cursor. This is convenient for spacing for- ward to a particular line location. The key-repeat delay time may be increased if you prefer a slow repeat rate. To increase the time between keystrokes, the only change neces- sary is to increase the BC count in line 780 of listing 1. For example, chang- ing the line to read: 0780 LD BC,1000 ;DELAY COUNT will provide an approximate 50-milli- second delay. The automatic key-repeat feature has the advantage of providing a built-in key debounce. Applications Applications of the MOD III utility features are many. From a cosmetic standpoint, the block cursor provides an aesthetic appearance in keeping with the image that the word "com- puter" conjures in the minds of many people. I've observed that people sit- ting at the keyboard for the first time appear to recognize the block cursor automatically as a silent prompt that expects them to do something. I prefer a block cursor simply because of its visibility. The video-screen-print capability allows you to print out information that may not otherwise be available without altering the program in memory. It is particularly convenient in printing a graphics display, pro- vided the printer has graphics capability. Automatic key repeat is a nice fea- ture to have, particularly because it costs so little in memory overhead, and I find it more convenient than counting characters when editing a program line. By holding down the space bar, you can quickly advance the cursor to the character to be edited. Admittedly, MOD III does not emulate all the features of the Model III; but it truly upgrades the capa- bilities of the Model I at a minimum cost in memory overhead. ■ Now available from your computer store- the whole line of AJ couplers and modems. Starting now you can buy AJ acoustic data couplers and modems directly from your local computer store. Not just selected models. Any models. Ranging from the 0-450 bps A 242A, the world's most widely used acoustic data coupler, to the revolutionary AJ 1259 triple modem that handles 300 bps Bell 103, 1200 bps Bell 212A, and 1200 bps VA 3400 protocols. Whether you need full or half duplex or both in one; originate or answer, auto answer; acoustic coupling, or direct-connect— there's a model for you in the AJ line. Starting now you don't have to settle for second best. For the location of your local computer store handling the AJ line, call toll-free: 800/538-9721 California residents call 408/263-8520, Ext. 307. ANDERSON JACOB5DN 396 April 1982 © BYTE Publications Inc Circle 29 on inquiry card. We have ways « # 41 mm echo-si* £G tto BO to make it talk! Give your computer the magic of speech with an ECHO™ Speech Synthesizer! There are four new models to choose from: the ECHO 80 (TRS-80 models i & III), ECHO 100 (S-100), the ECHO GP (general- purpose, serial/parallel) and the (ECHO SBC (single board computer). These join the popular ECHO ][ (Apple). ECHO Speech Synthesizers use LPC synthesis pioneered by Texas Instruments, L combined with a phoneme-based operating system to provide any vocabulary you desire while using a minimum of your computer's memory. The TEXTALKER Speech Generator, stan- dard with all ECHOs except the SBC, translates normal English text to speech automatically. Simple commands allow you to select from: 63 different pitch levels Words spoken monotonically or with intonation Fast or slow speech output Entire words pronounced or spelled letter by letter Different volumes i Spoken punctuation if desired Speech applications are virtually unlimited, ranging from education to games to aiding the handicapped. The flexibility and low price of ECHO Speech Synthesizers make them the logi- cal choice when adding speech to your system. For more information see your dealer or contact: STREET ELECTRONICS CORPORATION 3152 E. La Palma Avenue, Suite D Anaheim, CA 92806 Telephone: 714/632-9950 Circle 387 on inquiry card. fsEcl ' ■ * i Binary-Coded Text A Text-Compression Method Trim text size by encoding common character strings. Dr. Richard Tropper Department of Psychology Rhode Island College Providence, RI 02908 The time is approaching when in- creasing quantities of textual infor- mation will be committed to comput- er storage. Newspapers, professional journals, and library materials in general all lend themselves to reduc- tion to some form of binary coding. Binary coding, in turn, promises to facilitate storage, access, transmis- sion, and searches of much of the material that traditionally has been reduced to the printed word. At present, reduction of text to binary code is usually accomplished by translating each character of the text into a byte of data. Often, this is a wasteful strategy that fails to take advantage of redundancies and pat- terns within the English language as it is used. An alternative to character- byte storage of English-language text is the use of binary-coded text. Binary-coded text exploits the repetitive nature of typical written English to provide economies on the order of 60% of medium require- ments over traditional character-byte storage. These savings are achieved without loss of information. The inefficiency of character-byte storage is apparent when one con- siders the memory devoted to storing a typical six-letter word. Such a word requires 7 bytes of memory— the first 6 bytes store the six letters and the seventh byte stores the trailing blank. Those 7 bytes occupy 56 bits of mem- ory and can take any one of 2 56 pos- sible states. If there were on the order of 2 56 different six-letter words in the English language, then allocating 7 bytes to store one of them might be justifiable. There are, in fact, considerably fewer than 2 56 six -letter words in the language. One recent compilation analyzed the contents of 500 samples of English language text {Computa- tional Analysis of Present-Day American English, H. Kucera and W. N. Francis. Brown University Press, 1967). Those 500 samples of text com- posed a body of text 1,014,232 words long, but, all together, there were only 50,406 unique words, of which only 6470 were six letters long. Even allowing for the obvious fact that Kucera and Francis did not conduct an exhaustive search of the totality of written English text, it seems ap- parent that the allocation of 56 bits is an extravagant expenditure of mem- ory for the identification of a six- letter word. Theoretically, the number of unique character strings that can appear in English-language text is infinte, but in practice it tends to be quite limited. A typical sample of text is composed of the repetitive use of a few common words and the occasional use of ob- scure ones. Kucera and Francis re- ported that within their million-word corpus of text the most frequently oc- curring word, "the," appeared 69,971 times. That word alone accounted for nearly 7% of the words in the text they examined. They further reported that the 100 most frequently used words accounted for some 47% of their corpus of text, and the 1000 most frequently used words ac- counted for a little more than two- thirds. Not only are a few common words heavily relied upon, but when a less common word is used, it tends to be reused within the same passage. The result is that the number of unique words that appear in any given sample of text tends to be relatively small. The data reported by Kucera and Francis suggest that a typical 2000-word passage would be 398 April 1982 © BYTE Publications Inc SPECIALS WE CARRY THE COMPLETE LINE OF ATARI SOFTWARE, PERIPHERALS AND ACCESSORIES. I I EPSON MX ATARI 400 16K I INTERFACES & CABLES IEEE $55. RS-232 $70. APPLE INTERFACE & CABLE $90. +m**g* /t ft TRS-80 CABLE $35. $43 T . Oil W/GRAPHTRAX $459.00 $339.00 PERSONAL COMPUTERS Televideo 925 849.00 Televideo 950 929.00 CBM 8032 Computer 1 149.00 CBM 8050 Disk Drive 1 349.00 CBM 4032 Computer 975.00 CBM 4040 Disk Drive 975.00 CBM 4022 Printer 649.00 CBM VIC-20 269.00 Microtek 16K Ramboard for Atari 800 79.00 Microtek 32K Ramboard for Atari 400 and 800 1 49.00 Qume Sprint 9/45 (Full Panel) 2095.00 Atari 810 Disk Drive 449.00 Atari 850 Interface 169.00 Atari 830 MODEM 159.00 Atari 800 V6K 749.00 Epson MX-70 319.00 Epson MX-80 FT 549.00 Amdek Video-300 199,00 Hayes Micromodem II (Apple II) 299.00 Sanyo 9" B & W 1 89.00 NEC 3510 Spinwriter $1750.00 NEC 3515 Spinwriter 1795.00 NEC 3530 Spinwriter ' 1 750.00 NEC PC-8023 Printer 629.00 NEC 7710 Spinwriter 2345.00 NEC 7720 Spinwriter 2695.00 NEC 7730 Spinwriter 2345.00 NEC JC 1201 M(A) — Color 12" monitor 359.00 Okidata Microline-82A 499.00 Okidata Microline-83A 729.00 Diablo 630 1995.00 M & R Sup-R-Terminal 279.00 Microsoft Soft Card (Z-80) 279.00 Microsoft Ramcard 16K for Apple 149.00 Hazeltine 1420 799.00 Amdek 100 G j 169.00 Anadex DP-9500/9501 1 249.00 Televideo 910 j 559.00 Televideo 91 2C 669.00 Televideo 920C 689.00 CALL TOLL FREE! 1-800-556-7586 COMPUTER SHOPPING CENTER INC. 12 Meeting St. Cumberland, Rl 02864 1-401-722-1027 TELEX 952106 COMPUTER SHOPPING CENTER We Accept C.O.D.'s • Stock Shipments Same Day or Next • No Surcharge for Credit Cards • All Equipment Factory Fresh w/MFT Warranty • We Carry the Complete Line of Personal Software • Prices do not Reflect Shipping Charges Rhode Island Residents please add 6% Sales Tax NEC GREEN 12 MONITOR JB 1201 M $159.00 OKIDATA MICROLINE 80A MATRIX PRINTER $329.00 a AMDEK C010R-1 MONITOR $339.00 EPSON MX 100 FT PRINTER $729.00 PRICES ARE SUBJECT TO CHANGE WITHOUT NOTICE Circle 110 on inquiry card. BYTE April 1982 399 expected to contain fewer than 800 unique words. Actually, English as it is used is even more limited than these data suggest. Kucera and Francis analyzed their work in terms of word types — unique concatinations of letters. Many of the word types that they counted are simply multiple deriva- tives of the same word root. A ran- dom sampling of their word lists in- dicates that 12% of the 50,406 words they cataloged can be formed by adding M s" or "es" to other entries within the list. Another 4% can be formed by adding "d" or "ed." Ob- viously, English as it is used relies on a rather small word base. These properties of English-lan- guage usage suggest a strategy for the efficient storage, transmission, and search of English-language text. It is possible to construct a relatively brief dictionary of the character strings most frequently used in English and to assign a unique binary code to each. Then, for any given text to be encoded, a supplemental string list of those strings found to occur within the original text, but not within the dictionary, is put together. The original text is reduced to a series of pointers that indicate entries in either the dictionary or the string list. For such a text, all that needs to be stored is its string list and its pointer list. A decoding program that contains the dictionary within itself can recon- struct an accurate image of the More Significant Byte 15 14 13 12 11 10 9 8 4-bit word Ending Code Higher 3 Bits Of Dictionary Address * Dictionary 1 = String List original text from its string and pointer lists. Experience with this technique has shown that the lists for such a text would require only about 40% as much medium for storage and corre- spondingly only about 40% as much time for transmission as the same text storage in traditional character-byte format. String searches of binary- coded text achieve even greater ad- vantages over searches of character- byte text. If any of the elements of a target string are not found in the dic- tionary or in the string list of a given text, then there is no need to scan the pointer list of that text to see if the elements appear in the required order. Beginning the Encoding Process Encoding any given piece of text into binary-coded text is a matter of replacing each character string in the original text with a pointer code. Each pointer is a 2-byte code that identifies a string in either the dic- tionary or in the string list. (See figure 1.) Bits through 6 and 8 through 10 of each pointer code are address bits. Bit 11 indicates whether the diction- ary or the string list is being ad- dressed. Bits 12 through 15 indicate one of the recognized word endings shown in table 1. When the pointer is decoded, it is printed as the string to which it points plus the word ending to which it points and an implied trailing blank. Less Significant Byte 7 6 5 4 3 2 1 1 j I Low Of Add er 7 Dicti ress Bits onarj Continuation Code Bit Figure 1: Diagram of a binary-coded text pointer. Of the 16 bits available, 10 are allocated to dictionary addressing, four define the word-ending code (given in table l) f one identifies the dictionary being addressed, and one is a continuation code. In a text stream, the less significant byte appears first. If bit 7 is a 0, this signals that the more significant byte is all zeros and that the next byte is the less significant byte of the next pointer. 400 April 1982 © BYTE Publications Inc Bit 7 of each pointer is reserved as a continuation code. When this bit is low, it indicates that the pointer has been abbreviated to a single byte and that bits 8 through 15 are implicitly 0. The effect of implying zeros in bits 8 through 15 is to allow the abbrevi- ated, 1-byte pointers to address the first 128 entries in the dictionary while indicating the null string as the word ending. This permits these 128 entries to be represented by 1-byte, rather than 2-byte, pointers. The first 24 entries of the dic- tionary are reserved for punctuation marks. (See table 2, page 404.) There are three general classes of punctua- tion marks: leading punctuation, trailing punctuation, and special codes. The pointers that indicate leading punctuation decode into the mark they represent but do not generate an implied trailing blank. The pointers for trailing punctuation do generate a trailing blank, but they suppress the trailing blank of the preceding character string. Capitalization of the first letter in a word is treated as a form of leading punctuation. During encoding, leading and trailing punctuation are stripped off each string to which they are found attached. The leading codes, if any, are added to the pointer list, followed by the code for the root string, then by the codes for trailing punctuation, if any. For example, if the English text contained the string: "Hello!" U 4-Bit Hexadecimal Word Code Ending (null string) 1 ments 2 ment 3 mgs 4 ions 5 ely 6 ers 7 ion 8 ing 9 iy A ed B 's C er D es E s F e Table 1: Hexadecimal codes assigned to recognized word endings. Solve the EnergyGrisiswith f%4 "m \b£&W»l Saving energy and money is as easy as switching light bulbs This free slide rule calculator from Westinghouse shows you where to begin. Saving energy is every- one's job. You can make it easier, however, if you take a close look at the lamps you're using now. With the Westinghouse Energy-Saving Calcu lator, you can instantly analyze each lamp type's efficiency, and decide exactly which kind of bulb is more efficient in offices, plants, showrooms and display areas. You'll also learn how many watts you save and the annual energy cost savings per lamp. As an example, if you have fluorescents, substituting our Econ-o-Watt lamps for standard lamps will have an immediate effect- up to 6 watts per socket, with no appreciable change in light level. For incandescents, the most efficient way to save, besides direct substitution, is by replacing your system with high pressure sodium lamps. These lamps can save up to 80% of the energy Circle 434 on inquiry card. »'f.S expended 1 incandescents, while producing an equivalent light level. Call toll free 800-631-1259 to get your calculator. Westinghouse lamp products and programs offer many other savings opportunities that can make the difference in your operating expenses. Call today and learn why the simplest, most straightforward solution to saving energy is taking matters into your own hands. © Westinghouse Lamp Divisions Bloomfield, New Jersey 07003 BYTE April 1982 401 the corresponding pointer list entry would be: 06 04 xx xx OB 08 where xx xx is the pointer code for "hello." The special-punctuation codes in- clude 03 for "space/' which is necessary whenever more than one fc separates two strings, and 00 for "end-of-line," which is effectively a linefeed/carriage return combination. Codes 01 and 02 are actually abbrevi- ations of frequently occurring con- catinations of punctuation codes. The 01 code replaces the sequence of hexa- decimal numbers "OF 03 04" when- ever that sequence is found in the pointer list. The sequence "OF 03 04" decodes as: [period, with implied space] [space] [capitalize first letter of next string] This is a common sequence that typically separates sentences of English-language text; it is efficiently abbreviated into a single byte, 01. Similarly, the special code 02 is the abbreviation for the sequence that begins each paragraph of English. The Dictionary After the 24 punctuation codes, the remaining 1000 entries in the diction- ary are character strings. Some repre- sentative entries in this dictionary (which is too long to be printed in its Pointer Code (Hexadeci mal) Interpretation 00 end-of-line 01 period-space-space-capitalize 02 space-space-space-space-space-capitalize 03 space 04 capitalize first letter of next string 05 leading single quote 06 leading double quote 07 leading left parenthesis 08 trailing double quote 09 trailing comma 0A trailing right parenthesis 0B trailing exclamation mark OC trailing question mark 0D trailing colon 0E trailing semicolon OF trailing period "I trailing single quote 12 13 14 15 > reserved (no present application assigned) 16 17 Table 2: Pointer codes for punctuation and other common occurrences. The codes shown here are the first 24 words in the dictionary. entirety) are given in table 3. The first string entry in the dictionary (the word "the"), therefore, appears at decimal address 24 and is assigned hexadecimal pointer code 18. The next 103 entries (decimal addresses 25 through 127) are assigned sequential hexadecimal pointer codes from 19 through 7F. These 104 entries are the 104 most frequently used words in the English language, according to Kucera and Francis. Together with the 24 punctuation codes, they oc- cupy the lowest 128 addresses in the dictionary. These are the 128 ad- dresses that can be identified with 1-byte pointers. Given that Kucera and Francis report that the 104 most frequently used words account for some 47% of written language and BITE Back Issues For Sale The following issues are available: $2.00 ea. $2.75 ea. $2.75 ea. $3.25 ea July 76 May 78 Oct. 79 Feb. 81 Apr. 77 June 78 $3.25 ea. Mar. 81 May 77 July 78 Nov. 79 Apr. 81 June 77 Aug. 78 Dec. 79 May 81 July 77 Sept. 78 Jan. 80 July 81 Aug. 77 Oct. 78 Mar. 80 Aug. 81 $2.75 ea. Dec. 78 Apr. 80 Oct. 81 Sept. 77 Jan. 79 May 80 Nov. 81 Nov. 77 May 79 June 80 Dec. 81 Dec. 77 June 79 July 80 $3.70 ea. Feb. 78 July 79 Aug. 80 Mar. 82 Mar. 78 Aug. 79 Oct. 80 Apr. 78 Sept. 79 Dec. 80 ' Payments from foreign countries must be made in US funds payable at a US bank. Prices include postage in the US. Please add $.50 per copy for Canada and Mexico; and $2.00 per copy to foreign countries (surface delivery). Send requests with payment to: BYTE Magazine 70 Main St, Peterborough NH 03458 Attn: Back Issues ' Please allow 4 weeks for domestic delivery and 8 weeks for foreign delivery. 402 April 1982 © BYTE Publications Inc sssss**® BYTES Best QgIIsp List Ciarcia's Circuit Cellar, Volumes I, II, & III by Steve Ciareia Collections of Steve Ciarcia's perennially popular columns from BYTE Magazine, these three volumes are sure to please home computer users and electronics hobbyists. Volume I includes power conversions, programming E^ROMs, remote terminal interfacing, touch- input video display, and more. Volume II, focusing on projects which interface the personal computer with the home, features useful applica- tions such as a computer-controlled home securi- ty system, computerized appliances, input-output expansion for the TRS-80, and even a computer- controlled wood stove. Volume III offers low-cost construc- tion projects such as an ultrasonic rangefinder, handheld remote computer control, two speech synthesizers, and a remote-control motorized platform, to name just a few. Build Your Own Z80 Computer This complete guide to building a working computer offers engineers, students, and hobbyists an exciting alternative to buying a computer. With clear instructions, Steve Ciareia fully explains how to build a basic single-board micro-computer based on the Zilog Z80 microprocessor. The finished product features a 1 K-byte operating system, serial and parallel ports, hexadecimal display, audio cassette mass storage, and easy expansion to include a video terminal. Circle 65 on inquiry card. W Please send _ Ciarcia's Circuit Cellar, Vol. I $8.00 _____ Ciarcia's Circuit Cellar, Vol. II $ 1 2.95 Ciarcia's Circuit Cellar, Vol. Ill $ 12.95 Build Your Own Z80 Computer $ 1 5.95 Call Toli-Free 800/258-5420 Name Check Enclosed Address Bill Visa/ MasterCard # City State Zip Expiration Date evil Bflfl^S 70 Main Street Peterborough, N.H. 03458 Please add .75 per book to cover shipping cost. B4 because punctuation is fairly com- mon in English, this scheme provides that a bit more than half the pointers for a typical sample of English- language text can be only 1 byte in Address (Decimal) 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 Code Pointer (Hexadecimal) 0018 0019 001 A 001 B 001 C 001 D 001 E 001 F 0020 0021 0022 0023 0024 0025 0026 0027 0028 07F5 07F6 07F7 07F8 07 F9 07 FA 07 FB 07 FC 07FD 07FE 07 FF Dictionary Entry THE OF AND TO A IN THAT IS WAS HE FOR IT WITH AS HIS ON BE KITCHEN PRODUC CLOTH FAILUR FAMOU LONDON PUBLISH QUICK REGARD YOU'LL ACTIY Table 3: Entries from the beginning and end of the dictionary of 1024 words or word parts. length. The remaining 896 string entries in the dictionary are stored in truncated form. Each of these entries is the re- sult of testing the trailing characters of an entry in Kucera and Francis's word list against each of the recog- nized word endings given in table 1 and lopping off the longest one from the right side of the word. The 105th entry in the dictionary, for example, is the word root "thos." This was generated by testing the 105th entry in Kucera and Francis's word list, "those," against the recognized word endings in table 1. The longest ending that matched was ' e," Therefore, "e" was lopped off "those," leaving "thos." The rest of the dictionary was built up in the same manner except that those entries in the Kucera and Francis list that would have resulted in multiple identical entries in the dic- tionary were ignored. Consequently, words such as "seem," "seems," and "seemed" resulted in only a single dic- tionary entry, "seem." This scheme allows multiple derivative words to be represented by a single word root in the main dictionary. String List The string list is created sequential- ly as the encoding program steps through the original text. Each time the encoder encounters a string, it strips that string of leading and trail- ing punctuation. The remaining string is then tested against each of the elements of the dictionary and against as much of the string list as has already been made up. If no match is found, the string is truncated by lopping off its longest recognized word ending. The dictionary and string list are then searched again. This time, if no match is found, the remaining truncated string is added to the string list. As the string list is being created, each entry is added to the preexisting list preceded by a single byte that in- dicates the length of the entry. For ex- ample, if the first three entries in the string list were "boy," "day," and "happy," the string list would initially Information 3 bo y3 day 5 happy Encoded Hexadecimal 03 02 OF 19 03 04 01 19 05 08 01 10 10 19 Table 4: An example of a string list. This sample shows the encoding of the words "boy, " "day, "and "happy. " A string list is a list of words and word pieces that belong in a coded passage of text but are not listed in the dictionary. THIS IS DIGITALKER OUT 127,0 This is all it takes to say this or 143 other expressions with MICRO- MOUTH*. Absolutely no software drivers or subroutines to load. MICROMOUTH*, the latest Circuit Cellar project can be used as an emergency annunciator, as an aid for the handicapped, for process control and automatic monitoring, and to add new dimensions to computer games. Sample phrases that can be programmed are: "THE TIME IS 4 HOURS 23 MINUTES . . .(BEEP)" "NUMBER 4 IS 3.47 VOLTS" "THE SPEED IS 100 METERS A SECOND . . SLOW DOWN" Thousands of expressions can be added by changing the ROM chips. MICROMOUTH* is plug compatible with APPLE II and TRS-80* com- puters. Directions are included for ,,5100, H8 and parallel port Operation . -DIGITALKER is a trademark of National Semiconductor Corp. Complete Kit (as shown) $120.00 Assembled and tested: Apple II $150.00 TRS^80 Model I w/power supply and cable $170.00 TRS-80 Model III $200.00 •MICROMOUTH is a trademark of Micromint Inc The MicroMint Inc. 917 Midway Woodmere, NY 11598 Dealer inquiries invited. call: 1800-6453479 fn/V.Y.5T6-374-6793 404 April 1982 © BYTE Publications Inc Circle 266 on inquiry card. ■ "IWtfU P *t# _m«_i « ^ THE ONLY BUSINESS-FEATURED UNDER $200 The GDC 103J-L The only low-cost 300 bps dial modem with the same features found in modems which support business applications ...or your home computer. Features: • Operates over all telephone lines even lines not usable by line powered units • Data flow indication shows transmit and receive activity • Carrier detect indication • Answer/Originate mode is automatically selected — no need to manually switch • Self diagnostics with Analoop®— loops data from terminal through modem to check operation Same high quality as our complete line of DataComm products. For more information contact the experts at: General DataComm Industries, Inc. One Kennedy Avenue Danbury, CT 06810 (203)797-0711 General DataComm Industries, Inc. General DataComm Industries (Canada) Ltd. 104-1220 Innes Road Ottawa, Ontario K1B3V3 (613)745-9174 Local Distributors Boston, MA (617)620-1800 Detroit, Ml (313)963-6017 Great Neck, NY (516)482-3500 Circle 184 on inquiry card. Los Alamitos, CA (213)431-4865 Los Angeles, CA (213)277-4562 Miami Lakes, FL (305)822-6750 Midland, TX (915)682-6806 Minneapolis, MN (612)535-5330 Orlando, FL (305)859-7450 New York, NY (212)687-2455 Philadelphia, PA (215)441-8600 Norwalk, CT (203)866-0533 Rochester, NY (716)546-5060 Oklahoma City, OK (405)364-2222 Tustin, CA (714)832-9920 BYTE April 1982 405 Models 82A, 83A & 84A from ASAP OKIDATA's new printer line represents a breakthrough in economical, quality printing. These new printers have more options and features than any previous OKIDATA printer. Faster print speed and throughput, full 96- character ASCII, and both Centronics and RS-232C interfaces standard, all at an affordable price. These models are idea! for home or business, personal or educational applications. And now, ASAP is offering these new printers at prices you won't want to miss. Compare the features below. Then call ASAP to order your OKIDATA printer today. Dealer inquiries invited. Features Okidata 82A 80 Column Printer Okidata 83A 136 Column Printer Okidata 84A 136 Column Printer Print speed 1 20 characters per second 120 characters per second 200 characters per second Throughput @80 Char./line 76 lines per minute 76 lines per minute 114 lines per minute Print technique Bidirectional Bidirectional Bidirectional Dot matrix 9x9 9x9 9x9 Character set Full 96-character ASCII Full 96-character ASCII Full 96-character ASCII Graphics characters 64 block characters 64 block characters 64 block characters Interface Centronics 8-bit parallel Standard Standard OPTIONAL (Specify) RS-232C (1200 bps) Standard Standard — Size (inches) 14.2Wx 12.9Dx5.2H 20.2Wx12.9Dx5.2H 20.2Wx12.9Dx5.2H Ribbon Standard typewriter Standard typewriter Standard typewriter Two New Features 2K Serial Bufferboard (RS-232) Optional Optional OPTIONAL (Specify) Okigraph, HI-RES Graphics 60 vert, x 66 horiz. dots/inch Optional Optional Standard Printers Epson MX-80 80 Column Dot Matrix Printer Character set: full 96-character ASCII with descenders Graphics characters: 64 block characters Centronics-style 8-bit parallel interface standard: Apple, TRS-80, RS-232 interfaces optional. MX-80 FT/Friction Feed MX-100/132 Column CALL FOR PRICE & DELIVERY Apple Parallel Interface: AEI-1 W/Cable $69.95 • Standard Interface • Compatible with Epson & Okidata Printers • On-board Firmware (2708) Optional Cables: $20.00 AEC-2/Atari to Epson Printer TREC-2/TRS-80 to Epson/Okidata Printer RSC-1 /RS-232 (male to male) Serial Interface SEI-1 . $55.00 • Asynchronous 300, 1200, 2400 or 9600 BPS • Compatible with Epson Printers • 75 to 9600 BPS Manufacturer/Model « Price Anadex-9501 W/2K buffer .$1295.00 Diablo-630RO $2095.00' C.ltoh Pro/Writer Call for price C.ltoh F-10 Printmaster Call for price Texas lnstruments-810 S1650.00 Modems Manufacturer Model # Price Novation CAT S 149,00 Novation d-CAT $ 160.00 Novation Auto-Cat S 229.00 DC Hayes Smart Modem S 245.00 DC Hayes Micro Modem II $ 320.00 (Apple) DC Hayes Micro Modem 100 $ 335.00 Lexicon Livermore UDS UDS Monitors Manufacturer Amdek Amdek Amdek Amdek Sanyo Sanyo Sanyo Sanyo Zenith Lex-11 LIV-Star 20M UDS 103 LP UDS 202 LP Model # 100/12" B&W 100-80 100G/12"Grn. Color-1 13" DM 5109CX/9" Grn, DM 5012/12" B&W DM5112ex/12"Grn. DM C6013/13" Color ZVM-121/12"Grn. S 139.00 S 149.00 $ 185.00 $ 245.00 Price S 125.00 $ 169.00 S 149.00 S 375.00 S 175.00 S 270.00 S 290.00 S 450.00 S 115.00 406 BYTE April 1982 Circle 461 on inquiry card. Terminals Manufacturer Model # Price Ampex Dialogue 80 $ 899.00 LearSiegler ADM-5 Call for price Lear Siegler ADM-3A Call for price Lear Siegler ADM-3A+ Call for price Lear Siegler ADM-31 Call for price Lear Siegler ADM-32 Call for price Lear Siegler ADM-42 Call for price Televideo TVI 910 S 625,00 Televideo TVI 912C $ 725.00 Televideo TVI 925 S 825.00 Televideo TVI 950C $ 925.00 Components 4116s (200 nS)/5290-3 Apple, TRS-80, Heath 1-15 $1.85 each 50-99 $1.60 each 16-49 S1.70 each 100 up ... . S1.40 each 2114 L-2/200nS Low-Power 1Kx 4 Static RAM 1-16 $2.80 each 50-99 .... $2.60 each 17-49 .... $2.70 each 100 up . . . $2.45 each 2708/450 nS 1K x 8 EPROM $3.00 each or 8/S22.00 2716/5 Volt 2K x 8 EPROM $4.95 each Support Chips 8080A-CPU ... S 2.50 Z80A-SIO .... $22.00 Z80A-CPU ... $ 8.95 8255AC5 .... $ 6.95 Z80A-CTC ... $ 8.95 8257AC5 .... $15.00 Z80A-DART . . $13.95 Regulators 320T5 $.80 320T12 $.80 340T5 $.70 340T12 $.75 Connectors 1-9 10-24 25 up DB25P $2.25 $2.15 $2.00 0B25S $3.25 $3.10 $2.90 DB25C $ .95 $ .85 $ .75 100 Pin IMSAI Gold/S-100 Soldertail Connectors $2.60 each or 10/S2.40 each Capacitors 1 @ 12 Volt Ceramic 8C each or 100/S7.00 DIP SOCketS — Low Profile Tin Soldertail Description 19 10-49 50-99 100 up 14 pin tin st $ .15 $ .13 $ 12 $ .11 16 pin tin st $ .16 $ .14 S .13 $ .12 18 pin tin st $ .19 $ .18 $ .16 $ .14 20 pin tin st $ .25 $ .23 S .21 $ .20 24 pin tin st $ .26 $ .24 $ .22 $ .20 28 pin tin st $ .32 $ .30 $ .29 $ .27 40 pin tin st $ .42 $ .40 $ .38 $ .34 SYSTEMS WITH SPICE from CALIFORNIA COMPUTER SYSTEMS FOR APPLE II™ USERS Synchronous Serial Interface Part Number 7712A Price: $149.00 Programmable Timer Part Number 7440A Price: $ 95.00 Asynchronous Serial Interface Part Number 7710A Price: $139.00 Calendar/Clock Module Part Number 7424 Price: S 99.00 3% Digit BCD A-to-D Converter Part Number 7470A Price: S 95.00 12K ROM/PROM Module Part Number 7114A Price: $ 85.00 Parallel Interface Part Number 7720A Price: $125.00 Arithmetic Processor Part Number 7811 A Price: $349.00 Centronics Printer Interface Part Number 7728A Price: $125.00 FOR S-100 USERS 32K Static RAM Board Part Number 2032C Price: $610.00 16K Static RAM Board Part Number 2116C Price: $290.00 64K Dynamic RAM Board Part Number 2065C Price: $550.00 Z80A CPU Board Part Number 2810A Price: $265.00 Floppy Disk Controller Part Number 2422A Price: $365.00 CP/M™ Version 2.2 Free With Purchase S-100 Mainframe Part Number 2200A Price: $475.00 2201A (220VAC) $475.00 S-100 Motherboard Part Number 2501A Price: $150.00 4-Port Serial I/O Interlace Part Number 271 OA Price: $245.00 2-Serial. 2-Parallel I/O Board Part Number 2719A Price: $275.00 4-Port Parallel I/O Board Part Number 2720A Price: $195.00 Cabinets* CAB5V — Single cabinet for either Shugart or Glume SW, floppy disk drives (cabinet only) $ 75.00 CAB8H — Dual cabinet for 8" floppy disk drives (horizontal mounting) 5 225.00 CABBy — Cabinet for 8" floppy disk drives (vertical mounting) $ 225.00 CAB8V/2F-9SMB — Desk top cabinet for (2) 8" Shugart or Qume floppy disk drives, 9-slot mother- board, card cage, fan, dust filter, power supply, and all power and drive cables . . . Call for price ASAP also provides a full line of high-reliability disk drive subsystems with either Shugart or Qume floppy disk drives Call for price •All cabinets come complete with power supply, fan and internal cables. Microbyte Boards Z80A/I-0 CPU Board • A complete single board Z80A CPU with serial/parallel interface (2) Ser. (3) Parallel • Fully compatible with proposed IEEE S-100 Bus Standard • Z80A CPU (4MHz version of the Z80) $329.00 Assembled & Tested Optional Monitor Program $40.00 64K Dynamic RAM Board • Fully S-100 bus compatible (4 MHz) • 64K x 8 bit dynamic RAM • Low power: +8VDC @ 700 mA +16VDC @ 100 mA -16VDC @ 25 mA • Built-in capacity with LED indicator and vector interrupt $475.00 Assembled & Tested Floppy Disk Controller • DMA to within 16 Mbyte of memory • State-of-the-art NEC765 LSI Controller • IEEE S-100 compatible • DMA arbitration allows use of multiple boards within a system $329.00 Assembled & Tested *CP/M $150.00 Available (Optional) 4-Port I/O Board • Quad RS-232-C serial ports. One 20 mA current loop port • Fully IEEE S-100 bus compatible • Asynchronous communications with Z80A'DART™ or synchronous commu- nications with Z80A-SI0/0™ • Full set of modem control signals, including Rl (Ring Indicator) • Easily configurable to any type of terminal interface $265.00 Assembled & Tested Cables Available (Optional) *CP/M® Trade Mark of Digital Research ATARI COMPUTER PRODUCTS ATARI 800 (16K) Personal Business Computer Features: • Computer console • Atari 8K basic • 57 full stroke alpha-numeric keyboard with four function keys • Operator's manual • RF modulator • Power supply Call for price ATARI 400 $349.00 Atari Optional Accessories Model # Description Price 810 Disk Drive System .....$ 455.00 820 40 Column Dot Matrix Printer $ 279.00 822 40 Column Thermal Printer $ 299.00 Laser Blast Cartridge 19.95 Freeway Cartridge 19.95 Kaboom! Cartridge 19.95 Stampede Cartridge 19.95 Ice Hockey Cartridge 25.00 Arcade Plus Ghost Hunter (Cassette) S 25.00 Ghost Hunter (Disk) $ 30.00 DISKETTES from ASAP Verbatim 5'A" Diskettes Part I Sector Price MD525-01 Soft 10/S27.50 MD525-10 Hard 10 10/$27,50 MD525-16 Hard 16 10/527,50 8" Diskettes FD32-1000 Hard 10/$35.00 FD34-1000 Soft 10/535.00 825 80 Column Dot Matrix Printer $ 625.00 830 Acoustic Modem $ 159.00 850 Interface Module $ 169.00 410 Cassette Recorder $ 80.00 CX30-04 Paddle Controls $ 17.95 CX40-04 Joysticks (pair) $ 17.95 INTRODUCING ASAP's Atari 800 16K RAM Module: $55.00 1 year warranty parts & labor Software Description Price Atari Basketball $ 30.00 Super Breakout $ 30.00 Chess $ 32.00 Video Easel $ 25.00 3-D Tic Tac Toe $ 25.00 Star Raiders I $ 36.00 Asteroids 5 32.00 Music Composer . S 42.00 Educational ROM $ 19.95 Assembler/Editor $ 45.00 Telelink I $ 24.00 Space Invaders $ 30.00 Kingdom $ 12.95 Missile Command $ 32.00 Biorhythm $ 12.95 Graph It L $ 17.95 Energy Czar : $ 12.95 Mailing List $ 19.95 Touch Typing ; $ 19.95 Stock Charting ! $ 19.95 Stock Analysis : $ 19.95 Bond Analysis $ 19.95 Word Processor ; $119.00 Personal Finance $ 64.95 Microsoft BASIC $ 75.00 Datasoft Atari Mailing List Disk 19.95 Atari Character Generator Disk 16.95 Text Wizard Disk 89.95 Micropainter Album 1 Disk 16.95 Micropainter Album 2 Disk 16.95 Le Stick Accessory 30.00 Innovative Design Software, Inc. Pool 1.5 HI-RES $28.95 On-Line Systems HI-RES Adv #0 — Mission: Asteroid Disk 19.95 HI-RES Adv #2 - Wiz & Princess Disk . . 25.00 Roadwork Disk 29.95 Jawbreaker Disk 25.00 Softporn Adventure (X-rated) Disk .... 25.00 The Next Step Disk 29.95 Personal Software Visicalc Disk 169.00 FOR HOME ENTERTAINMENT SYSTEMS Activision Dragster Cartridge 19.95 Boxing Cartridge , 19.95 Checkers Cartridge 19.95 Fishing Derby Cartridge 19.95 Skiing Cartridge 19.95 Bridge Cartridge j 25.00 Tennis Cartridge 19.95 All prices subject to change without notice. Call lor best price. ASAP offers a 30-day buyer protection policy: full money-back guarantee if not totally satisfied. Ordering Information: name, address, phone, ship by: UPS or Mail. Shipping charge: add $2.50 up to 1 lb. for UPS blue; add $1 .50 for U.S. Mail (U.S. only) ($25.00 minimum order). Call for larger shipments. Terms: We accept cash, check, money orders, Visa & Master Charge (U.S. Funds only). Tax: 6% Calif, res. COD's and terms available on approval (school PCs accepted). Memorex 5VV Diskettes Part# Side/Dens Sector Price MEM 3481 1 /Obi Soft 10/S26.50 MEM 3483 1/Dbl Hard 10 10/S26.50 MEM 3485 1/Dbl Hard 16 8" Diskettes 10/526.50 MEM 3060 1/Sgl Soft 10/535.00 MEM 3101 2/Sgl Soft 10/S45.00 MEM 3090 1/Dbl Soft 10/545.00 MEM 3102 2/Dbl Soft Scotch 3M Wk* Diskettes 10/555.00 Part# Side/Dens Sector Price 744-0 1/Sgl Soft 10/533.00 744-10 1/Sgl Hard 10 10/533.00 744-16 1/Sgl Hard 16 10/533.00 745-0 2/Dbl Soft 10/559.00 745-10 2/Dbl Hard 10 10/559.00 745-16 2/Dbl Hard 16 Maxell 5 'A" Diskettes 10/559.00 Part # Side/Dens Sector Price MD1 1/Sgl Soft 10/535.00 MD2D 2/Dbl Soft 10/549.00 MH1 1/Sgl Hard 16 10/539.00 MH2D 2/Dbl Hard 16 8" Diskettes 10/555.00 FD1-128 1/Sgl Soft 10/545.00 FH1-32 1/Sgl Soft 32 10/545.00 FD2-XD 2/Dbl Soft Elephant Memory Systems 10/S55.00 Part# Side/Dens Sector Price EMS-1 1/Sgl Soft $25.00 EMS 2 1/Dbl Soft 10/527.50 EMS 3 1/Dbl Hard 10 10/527.50 EMS 4 1/Dbl Hard 16 10/527.50 EMS 5 2/Dbl Soft 10/533.00 EMS 6 2/Dbl Hard 10 10/533.00 EMS 7 2/Dbl Hard 16 SRW Media Storage Cases 10/533.00 Part# Size Price SRW-5 5V." 52,50 ea. SRW-8 8" 53.25 ea. asaii computer ■ products, inc. 1198 E. Willow St.. Signal Hill. CA 90806 Toll free outside California: (800)421-7701 Inside California: 213) 595-6431 714)891-2663 Circle 461 on inquiry card. BYTE April 1982 407 Circle 290 on inquiry card. MB C SYSTEMS Inc. (203) 342-2747 COMPUTERS ONYX C8002 256K 10 MEG HD " " 18 MEG HD ALTOS SYSTEMS ACS 8000-2 1 MEG F ACS 8000-6 14 MEG ACS 8000-10 10 MEG COMMODORE CBM 9000 SUPERPET CBM 8300 LETTER QUA CBM-64 CP/M,64K,GRA $13590 $14990 CBM 8023 (132COL, 15 CBM 8052 2 MED FD ATARI 8 00 16K 400 16K ZENITH Z-89 GA Z-89 ALL-IN-ONE-SYS HEWLETT-PACKARD HP-85 HP-83 HP CALCULATORS - 20 XEROX SYSTEMS 810 5 1/4 FLOPPY S 820 8 " FLOPPY SYS NORTH STAR HRZ-1Q-64K-HD5 SAVE ADVANTAGE 64K-QD INTERTEC SUPERBRAIN 64K-DD 64K-QD D $2990 HD $8990 HD $6895 $1699 LITY $1990 PHIC $ TBA 0CPS)$ 799 $ TBA $ 749 $ 349 $2068 TEM $2275 $2395 $1790 ; OFF $$$ 'S $2395 $2990 $1600 $$$ $3550 $2775 $3180 DISKETTES SINGLE SIDE {BOX OF 10) $24 .50 DOUBLE SIDE (BOX OF 10) $35 .00 CABLES- - RS232 M/M 6 ' $17 .95 M/F 6 ' $18 .95 PRINTERS OLYMPIA ES-100 TYPEWRITER WITH, RS-232, PARALLEL, IEEE $1250 IDS PRISM-80 (200CPS) F/T $ 999 560-G 132COL $1090 PRISM-132 COLOR F/T $1690 CENTRONICS 739-1 $ 560 739-3 $ 675 OKIDATA MICROLINE 82A $ 495 MICROLINE 83A $ 749 EPSON MX-80, MX80-F/T, MX-100 $$$ IN STOCK INCLUDING CARDS&CABLES ALWAYS COMPETITIVELY PRICED $$ C . ITOH DIABLO 630 NEC SPINWRITER 7710/7730 NEC SPINWRITER 3510/3530 NEC SPINWRITER 7720 KSR ANADEX 9500/9501 TERMINALS TELEVIDEO 920C 912C 950 ZENITH 2-19 $1499 $1990 $2590 $1950 $2890 $1199 $ 775 $ 6 95 $1050 $ 820 ABOVE ITEMS MAY BE ORDERED BY MAIL OR PHONE. FACTORY SEALED, MANUFACTURERS WARRANTY INCLUDED PRICES SUBJECT TO CHANGE (203) 342-2747 MULTI-BUSINESS COMPUTER SYSTEMS 28 MARLBOROUGH STREET PORTLAND, CONN. 064 80 jj| TWX/TELEX 710-428-6345 M 408 April 1982 © BYTE Publications Inc read as shown in table 4. ASCII re- serves the lower hexadecimal values for control codes, but those codes have no function in the string list. It turns out to be more efficient to give the 90 printable characters hexa- decimal codes ranging from 01 to 5A and to reserve the 165 higher codes of 5B through FF for multiple character representations. No extensive or sys- tematic research has been undertaken to identify the most efficient use of these 165 codes, but the following scheme was adopted and employed simply because it seemed reasonable. Casual inspection of a typical sample of English-language text sug- gests that, within words, vowels are rarely separated by more than two consonants and that consonants are rarely separated by more than two vowels. This leads to the observation Hexadecimal Hexadecimal Hexadecima Code Digraph Code Digraph Code Digraph 5B BA 92 PE C9 EH 5C BE 93 PI CA EL 5D Bt 94 PO CB El 5E BO 95 PU CC EN 5F BU 96 PY CD EP 60 BY 97 RA CE ER 61 CA 98 RE CF ES 62 CE 99 Rl DO ET 63 CI 9A RO D1 EV 64 CO 9B RU D2 EW 65 CU 9C RY D3 IB 66 CY 9D SA D4 IC 67 DA 9E SE D5 ID 68 DE 9F SI D6 IF 69 Dl A0 SO D7 IG 6A DO A1 su D8 SH 6B DU A2 SY D9 IL 6C DY A3 TA DA IM 6D FA A4 TE DB IN 6E FE A5 Tl DC IP 6F Fl A6 TO DD IR 70 FO A7 TU DE IS 71 FU A8 TY DF IT 72 FY A9 VA E0 KV 73 GA AA VE E1 IW 74 GE AB VI E2 OB 75 Gl AC VO E3 oc 76 GO AD SH E4 OD 77 GU AE VY E5 OF 78 OY AF WA E6 OG 79 HA B0 WE E7 OH 7A KE B1 Wl E8 OL 7B HI B2 WO E9 OM 7C HO B3 QU EA ON 7D HU B4 WY EB OP 7E HY B5 AB EC OR 7F LA B6 AC ED OS 80 LE B7 AD EE OT 81 LI B8 AF EF OV 82 LO B9 AG F0 OW 83 LU BA AH F1 UB 84 LY BB AL F2 UC 85 MA BC AM F3 UD 86 ME BD AN F4 UB 87 Ml BE AP F5 UG 88 MO BF AR F6 TH 89 MU CO AS F7 UL 8A MY C1 AT F8 UM 8B NA C2 AV F9 UN 8C NE C3 AW FA UP 8D Nl C4 EB FB UR 8E NO C5 EC FC US 8F NU C6 ED FD UT 90 NY C7 EF FE EX 91 PA C8 EG FF ST Table 5: A list of 165 common digraphs (tw o-letter zombinations) . "Without touching your program I can move it to and from Z80, LSI-IT," 8086, 6502, 8080, 6809 68000 and 9900-based computers." JULIE ERWIN, Vice President, Marketing, Soflech Microsystems, Inc. ■w *Tou can do it too, with Y SofTech Microsystems' unique software development and execution environment, the UCSD p-System™. Our UCSD p-System is the only genuinely machine-independent operating system for 8-bit and 16-bit microcomputers. And to over 50,000 end-users and scores of applications developers it is the one proven, reliable answer to software obsolescence. For software development, it allows you to work in any combination of UCSD Pascal™, FORTRAN-77, BASIC, and assembly language. It provides support for dynamic memory management and multitasking, with a full arsenal of powerful enhancements, such as a versatile Screen Editor, Native Code Generators, a Print Spooler, TURTLEGRAPHICS and XenoFile™, for easy access to CP/M® disks and files. 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Information Encoded Hexadecimal 03 5E 19 03 67 19 C9 BE 96 Table 6: An example of a more compactly coded string list. This example uses the same words as table 4 but compresses all possible two-letter combinations into 1 byte as given by the entries of table 5. The encoding of the 2 bytes representing "5h" into the single byte, hexadecimal C9, is not a mistake; this will be interpreted correctly by the decoding algorithm. that words are largely composed of a series of consonant-vowel or vowel- consonant digraphs. Table 5 is a list of 165 such digraphs. Notice that within table 5 a few of the less likely consonant-vowel and vowel-conso- nant digraphs have been replaced by a few of the more likely consonant- consonant digraphs. Each digraph is assigned one of the hexadecimal codes from 5B through FF. After the encoder has stepped through the entire original text and created the complete string list, it is possible to shorten the string list by scanning it for each of the digraphs coded in table 5 and, when a recog- nized digraph is found, abbreviating it to the appropriate single-byte hexa- decimal code. The result is that the string list of "boy," "day," and "hap- py" is compressed into the string shown in table 6. Notice that the hexadecimal code for the "5" preceding "happy" is 05. The hexadecimal code for the letter "e" is also 05. So far as the compress- ing routine is concerned, there is no difference between "5" and "e," so the "5" and the "h" in "happy" end up being compressed into the digraph "eh" and assigned the hexadecimal code C9. When the encoded text is be- ing decoded and the logical inverse of the compressing routine is being per- formed, the "5" reappears to serve its indexing function. Compressing the string list in this manner reduces its length by about 30%. An Application To demonstrate the practical ap- plication of binary-coded text, I have reduced a copy of the Gettysburg Ad- dress from normally encoded text to binary -coded text. A copy of the original appears in table 7. The re- sulting binary-coded-text pointer list and string list appear in table 8. In normal character-byte format, the original text occupies 1474 bytes of memory. The pointer list and string occupy 486 and 136 bytes respective- ly, or a total of 42% of the length of the original text. Table 9 shows the reconstruction of the first line of the Gettysburg Address from the binary- coded text. DISKETTE «SALE» Wabash: $24.90 oinch— *■ SS/SD: More Avail. QTY PRICE AVAI SPECIALS ZENITH ZVM-121 Nm Mm i tit /Green 1 2 nek ^4 15 MHz Af * 118.50 8255^*5.95 8748-8 -**3L00 3341PC— $ 2.00 MM5060 — 35« MC6800 ~£7Jf& MC6802 - *1495 MC6850 — *450 MC6821 — *4.95 REAL-TIME CLOCK CALENDAR (MSM 5832) 0«ri»tia» Mono M«tal Oat* CMOS I C Futirt) Thtw, Month Date Yaar A Day of WMfc -Bus OMntod -4 Bit Data But # 7 >| fv MBit Addraw »«HO •R/wMoldSal»e * *'S«Ci -Inter Signal XTAL '32 7B6KKI Hal Control $ 1 5v Pow Sup Powwr DisMpatkm 2.85 COMPUTERS ATARI" 800™ COMPUTER SYSTEM 400w/16K *350.00 800w/l6K *699.00 "800 Computer w/48K $825.00 ATARI PERIPHERALS: GLOBAL LPK-1: Logic Probe Kit -complete nothing extra to buy. Mm pulse width SOOnsec. ♦ia95 o o o O A OQ 10 Si/ifis ii fitifliuiei 1 THE MPD 117 1 turns an ordinary outlet into a cont- rolled power source I $ 79.50 0UW-TM ^/logical DEV. "EPRQM-Emei"» ■Erase up to 15 EPROM'S $69.95 in 30min. Printer "825"- 650°° Disk Dr~810- 485P° Record."410- 82PO Paddtetpr.) >1695 Joystick (pr.K 32kRAM-17a96 Basic Cart- 49P° Asteroids . Misste Com^ 32.50 Sup.Brk.Out Assem. Edit- 49°o Star Raiders- 45P° Basketball- 28P° Chess - 32PO + MONITORS* 1 Green Phos Hi-Res. — * 2. Green Phos. Hi- Res. — » Non glare Screen 3 Green Phos.-* Hi-Res. la. Lo-Res. — * *nft.5o^ t.99.50 £ *155.50 * CONCORD :«m * i i' j ft PRODUCTS 1971 SO. STATE COLLEGE ^ ANAHEIM, CALIF. 92806 >^- ( 714 ) 937-0637 ***T %nft A CHECK — M/0 ^°Iv» V °^ ^ NOCOO C COMPONENTS 74 S00 SN7400N SN7402N SN7404N SM7408N SN7410N SN7412N SN7413N SN7414M SN7416N SN7417N SN74 2GN SN7425N SN7430N SN7437N SN7438N SN744GN SN7442N SN7443N SN7445N SN7451N SN7454N SN7474N SN7475N SN7482N SN7492N SN7493N SN7495N SN7496N SN74122W SN74136N SN74141N SN74151N SN/41SJN SN74154M SN7415SN SN74157N SN7416QN SN74161N SN74163N SN741M 1 ! SN74165N SN74174N SN74175N SN 741 SON SN74181N SN74393N 74LS00 74 LSI 58 74LS181 74LS162 74LS163 74LS164 74 LS165 74LS169 74 LSI 70 74 LSI 74 74LS175 74LS190 74LS191 74LS196 74LS197 74 LS221 74LS240 74 LS241 74 LS243 74 LS244 74 LS245 74 LS2S1 74LS253 74 LS257 74LS259 74LS260 74 LS273 74 LS279 74 LS2SO 74 LS293 74LS36S 74 LS367 74LS373 74LS374 74 LS377 74LS669 74LS670 74SOO 74S02 74S03 74S04 74 SOS 74S10 74S15 /4S20 74S22 74S30 74S37 74SSO 74S51 74S64 74S74 74S86 74S112 74S132 2708 3.25m 8 for 2 95m 2716 &50m 8 tor 5.00a* 2732 12.95 m 4 tor 11.00 M 4iie 200ns. 'B/ *1.85eaJ $14P° OONS 2.25m OONS 245m 450NS 2.50m 10 tor 2.00m isc cont'd 74S138 75 74S140 1 OC 74S158 75 74S174 1 35 74 SI 75 1 35 MS182 75 74S189 4 25 74S201 6 75 74S240 2 75 74S244 2 95 74S251 2 75 745287 2 96 745288 2 95 74S299 5 75 745470 9 26 745471 9 50 745473 9 50 745474 9 50 2102 450NS 8038 AY5-1013A 4.25 cootroih* 1103A .75 UPD765 19.85 ftoppyda* m y mm 165 8T26 165 8T28 155 6212 155 6316 •45 IS4WSCW 25 IT410TRIAC 85 7905 85 7908 196 7915 55 7918 55 7806 45 7806 25 7806 165 7812 85 MC1330A1P 75 MC1350P 45 MCI358P 45 LM380 1.30 1.30 1.95 1.95 MH0026 03624 D3001 1.50 1.55 1.96 i.e. SOCKETS ♦0/5.3O 1CV5.70 1O/8.70 K>r9.70 1O712.70 10/13.70 iom.70 10717.70 p at 8 10/1.20 14 10/1.30 16 W1.40 16 10/ 1.80 20 10/2.70 22 10/2 TO 24 10/2.70 28 10/3.00 40 10/3.90 Bare Bones APPLE II Iw/o Keyboard w/o Pwr Supply , [*45a CPU a Z 80 7.96 Z 80ACTC 10.50 Z 80A CPU 10 50 Z 80 0O2 16-64K 129^)0 8O86A 13.50 2901 A 7.50 Mceeoo 9.50 410 April 1982 © BYTE Publications Inc Circle 124 on inquiry card. PUT YOUR APPLE TO WORK FOR YOU! WITH THE THUNDERCLOCK PLUS' kTM As an APPLE user you already know all the things your APPLE can do. Now Thunderware expands that list with the THUNDERCLOCK PLUS, the complete clock/calendar system for your APPLE! Your programs can read the month, date, day-of-week, hour, minute, and second in any of APPLE'S languages. On-board batteries keep your THUNDERCLOCK running accurately when your APPLE is off - for up to 4 years before battery replacement. But that's just the beginning. The THUNDERCLOCK PLUS is the most useful and versatile peripheral you can put in your APPLE. It can keep your disk files organized by time-and-date-stamping them, it enhances the usability of many of the new business/professional software packages for accounting, filing, and time management, and it can remotely control lights and appliances for security or display purposes in your business or home. SOFTWARE PRODUCT COMPATIBILITY Many of today's important software packages for data-base management, business applications, communications, and time management are designed to use the THUNDERCLOCK PLUS. If you have or plan to purchase any of these packages, a THUNDERCLOCK will greatly enhance their usefulness. •VISIDEX* (Personal Software) *D& MASTER and MICRO-MEMO (Stoneware) ©MICRO-COURIER and MICRO- TELEGRAM (Microcom) ©THE CASHIER and THE STORE MANAGER (High Technology) ©BUSINESS PLUS and NET-WORKS (Advanced Data Systems) ...and many others! THUNDERWARE'S DOS-DATER Our new DOS-DATER software upgrades the regular DOS on your disks so that DOS will use the THUNDERCLOCK to time- and-date-stamp disk files. Every time a program is saved or a file is modified, the current date and time to the minute are stored in the CATALOG with the file's name. You can tell at a glance when a program was saved or when any file was last modified. And this time/date stamping feature is completely automatic. That means any program which uses DOS will time/date stamp its files! REMOTE CONTROL Add Thunderware'sj X-10 INTERFACE OPTION to your THUNDERCLOCK PLUS and your APPLE can control lights and appliances through your BSR X-10 Home Control System on your pre-defined schedules. Our powerful SCHEDULER software allows you to create and modify schedules easily and execute them in the 'background', while using your APPLE for other tasks in the 'foreground'. Use your APPLE for energy management, display and security lighting, or laboratory/process control. Our PASCAL Software lets you use all the THUNDERCLOCK'S features in PASCAL and sets the F)iler date whenever you boot. You get all this versatility in just one peripheral system. Backed by a full one year warranty. See your APPLE dealer for a demonstration, or contact us for more information. We'll give your APPLE the best time around! Suggested retail prices: THUNDERCLOCK PLUS $139 X-10 INTERFACE OPTION... $49 PASCAL SOFTWARE DISK $29 DOS-DATER/DEMO DISK $29 MANUALS ONLY,each $5 Distributed by Apple Computer, Inc. and Computerland Corp. THUNDERWARE, INC. P.O. BOX 13322 Oakland, CA 94661 (415>652-1737 "Requires software supplied on DOS-DATER/DEMO disk. BSR X— 10 is a trademark of BSR (USA) LTD. A^PLE II is a trademark of APPLE COMPUTER, INC Four score and seven years ago, our fathers brought forth on this continent a new nation, conceived in liberty and dedicated to the proposition that all men are created equal. Now we are engaged in a great civil war, testing whether that nation or any nation so conceived and so dedicated, can long endure. We are met on a great battlefield of that war. We have come to dedicate a portion of that field, as a final resting place for those who here gave their lives that that nation might live. It is altogether fitting and proper that we should do this. But, in a larger sense, we can not dedicate — we can not consecrate — we can not hallow this ground. The brave men, living and dead who struggled here, have consecrated it, far above our poor power to add or detract. The world will little note, nor long remember, what we say here, but it can never forget what they did here. It is for us the living, rather, to be dedicated here to the unfinished work which they have thus far so nobly advanced. It is rather for us to be here dedicated to the great task remaining before us— that from these honored dead we take increased devotion to that cause for which they gave the last full measure of devotion— that we here highly resolve that these dead shall not have died in vain— that this nation, under God, shall have a new birth of freedom— and that government of the people, by the people, for the people shall not perish from the earth. Table 7: The Gettysburg Address prior to encoding in binary-coded-text form as in i table 8. (8a) 04 13 64 98 62 E0 07 81 A4 03 98 C1 6F CA 04 04 D4 EA 9E 03 FF 9B 07 07 0C 07 F9 6F 8D D8 03 8E C9 EA EC C6 D1 C4 DD F6 06 92 70 12 F6 D4 EA A5 50 12 A8 07 68 69 05 CC 73 74 CC 6B F6 BB A6 74 06 79 0C 82 68 14 97 03 02 6D 04 A9 EE 06 98 A0 0C 99 D8 00 94 97 12 14 8C 0E 14 07 64 0E 61 F6 10 9A 94 9F 12 0B 5B 14 14 80 F6 04 6F 14 A3 2D 17 04 02 97 16 07 14 06 70 12 74 F6 0E 03 04 A3 13 0B 16 02 69 04 A9 DB (8b) 02 92 02 80 F8 1A BA 06 F5 E0 FB 02 09 66 84 64 F6 02 81 08 00 27 2C 82 08 1C 57 99 74 09 83 A8 1D 84 08 1A 00 85 A8 1B 18 86 78 1E 3B 8E 01 2F 87 A8 F4 07 OF 00 02 63 40 2F 88 A8 1D 1C 9F 01 E4 07 C9 01 09 93 86 CA C2 00 1E 99 74 32 61 99 74 4B 83 A8 1A 4B 85 A8 09 54 00 90 01 89 F8 01 40 2F C7 05 27 1C 9F 01 8A 08 19 1E C9 01 OF 00 40 33 A2 F1 1B 85 F8 1C 8B 78 19 1E DE 02 09 25 1C F1 03 00 C5 84 B1 F1 22 80 F1 45 BA F0 CB F2 3F EC D3 1E 1E 00 99 74 9D 01 EC F3 01 23 1F 8C C8 8D 88 1A CB C7 1E 40 00 7C 5F 2C OF 00 02 30 09 1D 1C 8F C2 B6 F2 09 40 54 2E 85 F8 8E 08 40 54 2E 00 8F F8 8E 08 40 54 2E 90 08 2C FB 03 01 18 91 F8 8E 01 09 00 EC 83 1A 9B 04 09 45 92 A8 BA F0 09 33 8F A8 23 09 D8 01 00 C1 F2 66 B9 06 9C C2 1B A7 04 32 93 08 01 18 8A 01 46 85 F1 00 AE F0 09 E9 03 90 01 A7 C5 09 4D 40 BA 01 BA F0 09 30 23 54 96 C1 00 94 08 4D 35 6F BA F0 01 23 1F 22 A8 01 18 EC 83 09 81 C2 09 00 1B 28 85 A8 BA F0 1B 18 95 A8 8F 01 36 35 33 00 B4 E2 D8 01 4B 96 98 97 A8 01 23 1F 81 C2 22 A8 01 1B 28 BA F0 00 85 A8 1B 18 9F 01 98 08 F2 86 71 A8 01 BE 08 1E 31 00 5B 99 A8 9B 04 40 A9 F1 E8 A3 9A 78 1B 1E CF F5 00 22 36 35 CB F2 18 9C 01 95 03 E9 F7 19 9A 78 8E 08 1E 00 40 BA F0 BE 91 9B F8 1E 5B 9B 04 E6 02 2E 33 9C A8 to 00 9D 08 8E 08 1E 2C 99 74 09 95 C1 AC 02 09 E6 02 33 1C 57 9E 08 19 00 DD 05 8E 00 1A 1E DC 21 19 18 81 F1 09 2A 18 81 F1 09 22 00 18 81 F1 E6 02 2E 9F 08 31 18 F4 04 OF 00 FF FF Table 8: The Gettysburg Address in binary-coded-text form. Table 8a is the string list for the Address; table 8b is the pointer list. Table 9 shows how the first words of the Address are decoded. Limitations While binary-coded text offers a significant potential for savings in media costs, it is not without its negative considerations. Encoding and decoding require time and mem- ory. Also, the strategies that binary- coded text incorporates for the economic storage of traditional English text do not prove nearly so ef- ficient when applied to irregular language or technical jargon. The time and memory devoted to encoding and decoding are not as great as they might appear. Encoding is by far the lengthier of the two pro- cesses. The work that I did in developing the encoder was done on a Radio Shack TRS-80, which takes just under 30 seconds to encode the Gettysburg Address. Decoding the Gettysburg Address, on the other hand, takes only a few seconds. In- asmuch as any given piece of text needs to be encoded only once and thereafter can be stored for decoding an indefinite number of times, the time devoted to encoding is not necessarily a significant considera- tion. Decoding takes place at a rate far in excess of human reading speed, so the decoding time is irrelevant in any configuration in which it is being performed by a dedicated unit (such as an intelligent terminal or a microcomputer). The size of the en- coder or decoder may or may not be a limiting factor: the encoder and decoder together, including the dic- tionary, occupy just under 10K bytes. The fact that the string list is limited to 1024 entries does not really limit the size of the text that can be reduced to binary-coded text. A string list of 1024 entries is probably large enough to accommodate a text of approximately 10,000 words. The encoder can simply treat a text of 20,000 words as if it were two separate texts of 10,000 words each and create a separate string list for each "text," Regardless of the number of string lists the encoder has to generate, the ratio of storage re- quirements for character-byte text to storage requirements for binary- coded text should remain relatively constant at a ratio of around 5:2. 412 April 19SL© BYTE Publications Inc 1 . The first line of the Gettysburg Address (as it appears on a 64-character wide display): to to b to fcFour toscore band toseven toyears fcago, feou r ^fathers ^brought bforth(lf-cr) 2. The string list for the first line of text of the Gettysburg Address: 4 Information Encoded Hexadecimal Code s c r f r t o 5 o h 04 13 64 98 70 12 F6 3. The pointer list for the first line of the Gettysburg Address. (Note that the 2-byte pointers appear in less-significant-byte/more-significant-byte order. Each separate pointer code has been underscored to assist the reader in distinguishing 1- and 2-byte codes.) 02 92 02 80 F8 1A BA 06 F5 E0 FB 02 09 66 84 64 F6 02 81 08 00 Decoded: 02 indent and capitalize first letter next word bbtobb 92 02 dictionary address 274 plus null word ending fourto 80 F8 string list address plus "e" word ending scor + 1A dictionary address 26 plus null word ending and to BA 06 dictionary address 826 plus null word ending seven b F5 E0 dictionary address 117 plus "s" word ending year FB 02 dictionary address 379 plus null word ending ago 09 trailing comma ,to 66 dictionary address 102 plus null word ending ourb 84 64 dictionary address 516 plus "ers" word ending fath + ersto F6 02 dictionary address 374 plus null word ending brought to 81 08 string list address 1 plus null word ending forthto 00 linefeed/carriage return eb sb Table 9: Reconstruction of the first line of the Gettysburg Address from the binary- coded text of table 8. Due to the fact that binary-coded text relies so heavily on its dictionary of frequently used words, its efficien- cy will necessarily suffer when it is confronted with atypical character strings. One tactic for coping with this problem is to use different dic- tionaries for different categories of texts. In fact, this enhances the effi- ciency of binary-coded text in general. A list of the 1000 most fre- quently used words to be found in a library of computer-science journals, for example, will be significantly dif- ferent from a list of the 1000 most fre- quently used words in a collection of back issues of the New York Times. There is no logical obligation to en- code all texts on the basis of the same dictionary. The only requirement of binary -coded text is that the decoding program have available the same dic- tionary as was used during encoding. ■ The complete encoded dictionary is available from the author for $10. Not for sale in any bookstore ! Not available at any price! The new Consumer Information Catalog ! It's the free booklet that lists over 200 helpful Federal publi cations; more than half, free. On topics like home repairs. Money manage- ment. Nutntion. Information that could help you to a better way of life. To get your free copy )ust wnte: CONSUMER INFORMATION CENTER, DEFT. E PUEBLO, COLORADO 81009 "psVfiW General Services Administration Log Apple LUyU by Harold Ableson The name Logo describes not only the evolving family of computer languages detailed in this book, but also a philosophy of education that makes full and innovative use of the teaching potential of modern computers. Apple Logo presents the Apple II user with a complete guide to the applications of this unique system and also includes a description of TI Logo for users of the Texas Instruments 99/4 computer. The designers' vision of an unlimited educational tool becomes a reality for the Apple II user who begins to work with this procedural language, Logo enables even young children to control the computer in self-directed ways (rather than merely responding to it), yet it also offers sophisticated users a general pro- gramming system of considerable power. Apple Logo actually teaches programming tech- niques through * Turtle Geometry"— fascinating exercises involving both Logo programming and geometric concepts. Later chapters illustrate more ad- vanced projects such as an "INSTANT" program for preschool children and the famous * 'DOCTOR" pro- gram with its simulated "psychotherapist." ISBN 0-07-00425-0 240 Pages Softcover, spiral-bound $14.95 Call Toll- Free 800/258-5420 BYTE Books 70 Main Street Peterborough, N.H. 03458 m Circle 66 on inquiry card. ■iHrara^iHi B-4 April 1982 © BYTE Publications Inc 413 News and Speculation About Personal Computing Conducted by Sol Libes ■ mandom Rumors: Word has it that IBM is developing its own floppy- disk drive for disks less than 5V* inches in diameter. IBM is also said to be telling po- tential parts suppliers that it expects to ship approximate- ly 1.2 million personal com- puters by 1984. And this coming summer the corpora- tion is expected to introduce a larger brother for its Per- sonal Computer. . . . Olivetti and Victor are expected to soon introduce systems that are software compatible with the IBM Personal Com- puter. ... In a change of plans, Hitachi Ltd. is post- poning introduction of its personal computer into the U.S. until late this year. Hitachi has been showing a prototype 6809-based sys- tem at trade shows. Re- portedly, they feel that they do not yet have enough soft- ware support for it. . . . Mat- tel Electronics is said to be readying a portable ter- minal/computer. . . . Xerox may be seriously considering a low-cost por- table terminal. . . you can expect similar introductions from Sinclair, Epson, H itachi, and Alcatel- Electronique (France) at the National Computer Confer- ence (NCC) show in June. All are expected to sell for less than $500. . . . Toshiba is ex- pected to show a portable computer (T-100) using an optional flat-screen liquid- crystal display at the NCC. . . . Rumor has it that Apple will not have its new data- base/electronic-mailer/user- friendly 68000 system ready for introduction at the NCC. . . . Micropolis is reported to be readying 8-inch Winches- ter-technology disk drives with capacities of 60, 90, and 180 megabytes for introduction later this year. W omputer Flea Mar- ket: On Saturday and Sun- day, April 17 and 18, several thousand computer hobby- ists will flock to Trenton State College, New Jersey, for the Trenton Computer Festival, the world's largest personal-computer equip- ment flea market. This an- nual event is now in its seventh year. Many swap and seller tables, spread over more than eight acres, feature everything from complete computer systems to tiny electronic parts. There will be speakers, user- group meetings, an indoor exhibition area, and a ban- quet. The Festival is sponsored by the Amateur Computer Group of New Jersey, the Philadelphia Area Computer Society, and the Trenton State Computer Society; the funds raised help support these nonprofit organiza- tions. For information, call (609) 771-2487 or write to TCF-82, Trenton State Col- lege, Trenton, NJ 08625. IM. lew Policies for In- tertec: Intertec has been receiving negative press comments lately regarding its warranty policies and other matters. The company has made a series of an- nouncements it feels will im- prove customer relations. Intertec will now pay return freight on defective equipment, during the war- ranty period, and on equip- ment that arrives damaged to the dealers. The company is instituting a money-back guarantee during the 90-day warranty. Customers may return their machines for any reason dur- ing that period and pay only a restocking charge of 5 per- cent for the first 15 days and higher percentages beyond that on a sliding scale. A new user hot-line is available to solve customer problems. Any problem un- resolved after 24 hours will be forwarded automatically to the product manager. A series of across-the- board price reductions were announced last month. The Superbrain has dropped from $3495 to $2995; the Superbrain QD from $3995 to $3495; and the high-end Compustar from $4495 to $3995, Several additional policy changes have been made to give Intertec dealers added flexibility in discount struc- tures. Intertec customers will now automatically become members of a company- sponsored user group, which will meet annually. The company is also sponsoring a new magazine for users. lore 68000 Systems: Systems based on Mo- torola's 68000 micropro- cessor are now available from Charles River Systems, Computhink, Codata Sys- tems, Cromemco, and Dual Systems Control, as well as Empirical Research Group, Evans and Sutherland, Future Systems, Fortune Systems, Microdasys, Omni- byte, Q1, and Wicat Sys- tems. This list will probably quadruple in size by year- end. And virtually all have or will have Unix-like operating systems. Most are designed to be multiuser systems, although they can be used by a single person. So far, most of the bus-oriented systems introduced use either the Multibus or the S-100 bus. Few, if any, are using the Versabus, specifically designed by Motorola for the 68000. The problem is that the Versabus requires very large and ex- pensive boards and connec- tors. Sinclair Flat-Screen: Sinclair Research Ltd. has disclosed an agreement with ICL (International Com- puters Ltd.), the largest com- puter maker in England, for ICL to produce a line of of- fice work stations that will use Sinclair's flat video screen CRT and the Sinclair version of BASIC. Plans are for the units to be intro- duced in Europe and possibly the U.S. in early 1983. The ultra-compact work stations will function as stand-alone computers and also will communicate voice and data via private telephone systems. Sinclair is also expected to show a prototype portable terminal using the flat screen at the NCC show. A flat-screen pocket television measuring 6 by 4 by 1 in- ches, retailing for about $100, is expected to be in production later this year. 414 April 1982 © BYTE Publications Inc At last, full feature general business software for micro-computers. Officially authorized derivations from the popular MCBA® mini-computer packages, these packages have been eased down to micros and made even more user friendly. The mini versions of these pack- ages are distributed by over 900 OEMs and dealers, and are in use at over 9,000 end user sites worldwide. And already these micro versions themselves are in use by thousands of end users. Written in RM/ COBOL™, these pack- ages run underCP/M @ , OASIS™, UNIX®, COS-990 ® and other operating systems. They run on dozens of brands of micro-computers, including properly configured models from Radio Shack II, "Our current recommendation for a big five accounting package is MBSI" Computer Dealer magazine January, 1982 Apple III, Zenith, Hewlett Packard 125, Xerox 820, ALTOS, ONYX and many more. Tens of man-years have gone into these packages, which comprise over 230 programs, 165,000 lines of struc- tured source code, and 1,800 pages of user and technical documentation. Our claim is simple: THIS IS THE BEST MICRO-COM- PUTER GENERAL BUSINESS SOFT- WARE AVAILABLE. And we stand behind that with a moneyback guarantee. If s no accident that Computer Dealer magazine recently endorsed MBSI soft- ware. So if you' re a re-seller looking for first class micro-computer software, contact us today. Micro Business Software, Inc. Dover Rd. 5 Dept. BY1 Chichester, NH 03263 U Phone: (603) 798-5700 MCBA. RM/COBOl. CP/M, OASIS, UNIX, COS-990 are trademarks respectively of Mini-Computer Business Applications, Inc.: Ryan McFarland Corp.; Digital Research; Phase One Systems. Inc.: Bell Laboratories; and Ryan-McFarland Inc. BYTELINES. The unit, which will have a display three times brighter than conventional television sets and will use one quarter the power, will be made by Timex. According to Sinclair, a major U.S. retail chain has already agreed to buy 300,000 sets. Sinclair has also disclosed that it is working on a short- distance electronic car that it hopes to have on the road before 1985. lore Flat-Panel Dis- plays: Several manufac- turers are already shipping flat-panel displays, suitable for use in video-style ter- minals, that are based on refinements of existing tech- nologies: gas-discharge (CD), vacuum-fluorescent (VF), and liquid-crystal (LC). Low- cost DC-type CD displays, also known as plasma displays, are already available in sizes as large as 12 lines by 40 characters. AC-type GD displays offer inherent pixel memory, and therefore do not require refreshing and exhibit no flicker; however, they are more complex and conse- quently more expensive. Electro Plasma, in Millbury, Ohio, already offers an AC GD display that displays 66 lines by 80 characters; Inter- state Electronic, in Anaheim, California, offers a 51 -line by 85-character display (512 by 512 pixels); and Fujitsu America offers a 25-line by 80-character display (also 512 by 512 pixels). Ise Electronics, Japan, holds the basic patents on VF technology and has licensed Nippon Electric Company (NEC) and Futuba, as well as its own Noritake Electronics division, to manufacture it. These com- panies are currently supply- ing VF displays with as many as 256 by 256 pixels. Color displays are also available on custom order. LC displays are also in- creasing in size. For exam- ple, Seiko Instruments, Tor- rance, California, is current- ly shipping 4-line by 32 -character displays. However, LC is the most ex- pensive of the three, and all are still considerably more expensive than the old cathode ray tube (CRT) standby. But prices are drop- ping as the technology im- proves and production in- creases. At this time, the GD display shows the best pro- mise of competing with the CRT R. reasoning Computer: The Department of Energy's Argonne National Lab- oratory and Northern Illinois University have developed AURA (automated reasoning assistant), a general-purpose program that appears to mimic some reasoning skills of the human mind. It eliminates the need to understand complex pro- gramming when using a computer to solve a prob- lem. The problem must be explained to AURA in terms it can understand, and sug- gestions must be made for AURA to investigate. AURA does not solve the problem; rather, it points out direc- tions for further study. I EEE Standards: The Binary Floating Point (P754) and Radix Free Floating Point (P854) standards are being voted on by the In- stitute of Electrical and Elec- tronics Engineers (IEEE) stan- dards committee members. Standards for Relocatable Object Code Format (P695) and High Level Language (P755) are in draft states. The IEEE Assembly Language Mnemonics Standard (P694) committee is extending the current standard (which most manufacturers seem to ignore) to include several of the newer 16- and 32-bit microprocessors. A commit- tee is being formed to work on a standard for CP/M. A committee on Software Benchmark Standards has also been formed. For more information on IEEE Com- puter Standards in develop- ment contact: Michael Smolin, Chairman, IEEE Computer Standards Com- mittee, c/o Synertek Inc., Box 552, MS#39, Santa Clara, CA 95052. R. esearch Cooper- ative: The Semiconductor Industry Association (SIA) is planning to fund basic reasearch projects at U.S. universities through a newly formed Semiconductor Research Cooperative (SRC). Dr. Robert Noyce, Intel Cor- poration vice-chairman and chairman of SIA, said SRC plans to raise $4 to 5 million from integrated-circu it makers this year. This is be- ing done in response to the huge Japanese investments in research and training of engineers. Manufacturers are being asked to con- tribute an amount equal to 0.1 percent of their sales of semiconductor devices. Japanese firms would not be welcome to join because American firms are not presently allowed access to research being conducted in Japan's VLSI (very-large- scale integration) lab- oratories. SRC would own patents produced by its efforts and would collect royalties from firms that use them. SRC will be staffed by 10 engineers, headed by a full-time direc- tor, and controlled by a technical advisory board. Companies so far par- ticipating in SRC are Intel, IBM, Digital Equipment Cor- poration, Motorola, Control Data, Advanced Micro Devices, National Semicon- ductor, and Fairchild Camera and Instrument. Notable for its absence is Texas Instruments. w. atchlng IBM: Sears has disclosed that, during its first two months of selling microcomputers via its five computer stores, IBM pro- ducts have taken a 'large lead in sales volume among products carried in the stores." IBM shares shelf space with the NEC PC- 8001A, Vector Graphic Series 3, and a Wang word processor. There are rumors that IBM will shortly announce an en- largement of its Personal Computer dealer base. Re- portedly, a large number of independent retailers have applied for dealerships and are awaiting a decision. In the meantime, dealers have been encountering some ^ availability problems because of the large de- mand for the Personal Com- puter. IBM has disclosed that it will enter the industrial robot market shortly. Rumor has it that the robot will be designed for high-speed assembly or component in- sertion, selling in the $125,000 range. I elephone Typeset- ting: For about two years now I have been sending many of the articles and books that I write (with Wordstar on my trusty old S-100-based personal com- puter) directly to a typeset- ter via modem (at 600 bits per second, during off hours, using the standard CP/M- modem protocol), to be typeset directly from my file. The turnaround time is terrific, and the prices are great because little labor is involved. The typesetter has his system operating auto- matically 24 hours a day so that I can dial in at any time 416 April 1982 © BYTE Publications Inc and send the file. His system receives it automatically, whether he is there or not. He then adds the necessary typesetting control char- acters and processes the file directly through his machine. Two or three days later the typeset text is in my mailbox. Typesetters across the country are recognizing the value of hooking up per- sonal computers to their typesetting machines and the phone lines. Check your Yellow Pages for such ser- vices in your area. E EPROM Update: Elec- trically erasable program- mable read-only memories (EEPROMs) allowing erasure of bulk memory and Elec- trically alterable ROMs (EAROMs) allowing altera- tion of individual bytes are finally coming to the market- place. They allow real-time program changes, have reasonable access speeds, and come in less expensive packages than standard EPROMs that are erased by ultraviolet light. At the pre- sent time they cost eight to ten times more than EPROMs. However, as pro- duction increases they are expected to drop to a com- petitive price and supersede EPROMs. Already 16K-bit EEPROMs (2K by 8 bits) are available in limited quantities from Intel, National, General Instrument (Gl), and Motorola. And even Hitachi has announced a 64K-bit (8K by 8 bit) EEPROM. In an interesting turn of events, Intel has gone to court and received a preliminary injunction against Seeq Technology pro- hibiting sharing of EEPROM technology with Zilog or any other company. EAROMs are also available in limited quantities from Gl, National Cash Register (NCR), Nitron, and Toshiba. NCR even makes a 2K by 8-bit EAROM. However, ac- cess times are measured in microseconds and dual power sources are required. In the meantime, 64K-bit EPROMs are reaching full production status, and 128K-bit EPROMs are being sampled. Sixteen-bit-wide EPROMs are expected shortly. A\OAPSO Grant Pro- gram: The Association of Data Processing Service Organizations (ADAPSO), Arlington, Virginia, has established a grant and fel- lowship program for post- secondary students pursuing careers in the computer- services industry. Awards will be up to $1000 per re- cipient per academic year. The deadline for applying is April 20, 1982. u 'nix Look-Allkes: Manufacturers are finally starting to ship the 16-bit Unix-like operating systems they've been advertising for the past year. Some even claim to have Unix-like sys- tems for 8-bit computers. A few have been shipping these 8-bit systems for sev- eral months now. Bell Laboratories even has a Z80 version that it is using in- house. As reported last month, Western Electric, bowing to the Unix-like com- petition, has substantially lowered the price of Unix. It will be a few more months before we know how these new Unix-like systems for the 16-bit systems stack up. Below are some initial im- pressions. Unix was designed by Bell Labs to run on the Digital Equipment Corp. PDP-11 models. Although it has been implemented on small PDP-11s, it runs best, with full-feature performance, on the larger PDP-11 machines that have a sophisticated memory-management hard- ware system. Therefore, to transport Unix to a micro- computer means that it too must have ample memory (at least 256K bytes) and a memory-management sys- tem, a good disk system, and a tape backup system for good measure. Unix was ^vritten in C, a high-level systems-oriented language. Therefore, one would think that transport- ing Unix fron(i one hardware system to another would be an easy job — somewhat on the level of transporting CP/M with its easily modi- fied assembler-language BIOS (basic input/output system) module. However, because of Unix's orienta- tion to the; PDP-11 large- system architecture, this conversion takes a few pro- grammer-years to accom- plish. Hence the delay in releasing these implementa- tions. In order to cope with this problem, Microsoft, operating under a Western Electric Unix license, has entered into agreements with some other software houses to convert Xenix, a Unix look-alike, to systems for which Microsoft has not yet implemented Xenix sys- tems. The result is that the microcomputer Unix look- alikes are n6t full Unix im- plementations. Many of the larger or less used utilities have been omitted (or, in some cases, they are avail- able at an extra charge). In many cases the floating- point arithmetic or bit-fields have beerj omitted or restricted. Furthermore, many have adopted dif- ferent conventions for func- tion and system calls, library modules, and utilities. But even Bell Labs has not main- tained compatibility be- tween Unix implementations the way Digital Research has with CP/M. It is still very early in the Unix versus Unix look-alikes competition. Some suppliers of Unix look-alikes have done a very good job. Others still have a long way to go, but there is no doubt that they will make improve- ments. Japan Gaining on U.S: A recent report given by Commerce Undersecretary Lionel Olmer to the House Ways and Means Trade Sub- committee reported that Japan is moving along in a commitment to develop a world-scale computer indus- try. He reported that the Japanese government's policies, research programs, special tax incentives, direct financial assistance, and joint government-industry efforts were all aimed at "moving the Japanese com- puter industry to the tech- nological forefront in every major area." He also reported that they are now concentrating on improving their software capabilities and developing the computer of the future. "There has been a national consensus in Japan that their economic future depends upon a rapid evolution into a knowledge-intensive and technology-intensive economy." He went on to state: "I believe that the real challenge from Japan is just beginning." Mr. Olmer concluded by stating that a change in "na- tional attitudes" is required for the U.S. to retain its posi- tion as the world's premier industrial power. "We must work 'smarter' and save more. We must be willing to take risks. Only in this way can we restore our com- petitive edge, and 'made in America' will again be the unquestioned world stan- dard for quality." April 1982 © BYTE Publications Inc 417 Unwrap the Crypto Mystery TfTI'B 1 ! Thanks to the Western Digital CryptoPrimer™ ^^"^^^ ^^ Development Kit, $Jm ^^% 1 cryptography is no ^^B ^iJ^"% longer a deep, | %J^^P# dark secret. In fact, the kit is specially designed for personal computer owners and is based on the National Bureau of Standards' data encryption algorithm. Included in the kit are : a ^^ CryptoPrimer ™ manual, M WL i a cryptographic sys- ^^^ / tern built around our ^^^Qt/pttr* ^ WD 2001/2 data encryption chip, a con- venient RS 232 con- nector and a special hardware manual. All for just $495. Best of all, you'll end up with more than a clue on how to implement all the benefits of data encryption. So send your check or money order (including $9.00 for ship- ping and 6% sales tax if you're a Califor- nia resident) to: Western Digital, 2445 McCabe Way, Irvine, CA 92714. Please also specify your computer's make and model number. We think keeping cryptography a mystery is a crime. to* aki n( [9th71 ^, 9 e do e , 9ew °*kf you. WESTERN DiCiTAL CORPORA T / O A/ Telecommunications Division 2445 McCabe Way, Irvine, CA 92714 (714) 557-3550 418 April 1982 © BYTE Publications Inc Circle 433 on inquiry card BYTELINES. R. isndom News Bits: Victor Business Products has introduced an 8088-based system, called Sirius I, that is rumored to be software- compatible with the IBM Personal Computer. The Sirius I was designed by Chuck Peddle, the wizard who created the 6502 micro- processor and the PET com- puter. Reportedly, Peddle is being sued by Commodore for alleged breach of con- tract, and he is in the process of countersuing. . . . Honey- well's Minneapolis credit union reports that it now issues about fifteen interest- free loans a week for the purchase of personal com- puters by Honeywell employees. . . . National Semiconductor is finally shipping samples of its new super 16-bit 16032 micropro- cessor, with production quantities expected by mid- year CBS -TV is ex- perimenting with getting au- dience feedback via The Source (a timesharing infor- mation and telecommunica- tions utility accessed via modem) so that viewers can immediately let show pro- ducers know what they like and do not like about prime- time shows. . . . Matsushita Electric, Hitachi, and Maxell have agreed to standardize on a new 3-inch compact floppy disk. . . . Atari has reduced the suggested list price of the Atari 800 from $1080 to $890; however, it has increased prices on some software. . . . Sinclair Research reports that by the end of 1981 it had sold over a quarter of a million ZX81 personal computers and that U.S. mail orders alone are 4000 a week. . . . Micropro and Digital Research have filed a joint copyright-in- fringement lawsuit against Data Equipment Inc., Sunny- vale, California, and its parent company, Dataforce International Inc., for selling ''counterfeit copies" of their software. J u per/ Dupe r News: Super/Duper Computers Ltd., Pieinthesky, Utah, has introduced a revolutionary new computer, the Super/ Duper MAC-VIM. Based on a patented exclusive pipe- dream architecture, it boasts a speed faster than a bullet. The computer itself is so small that it seems lighter than air, and a new mass pro- duction technology is ex- pected to result in a selling price as cheap as dirt. The MAC-VIII cannot be over- loaded since it is made of solid steel. The computer will be marketed exclusively by Brooklyn Bridge Sales Inc. . . . Happy April! MAIL: I receive a large number of letters each month as a result of this column. If you write to me and wish a response, please include a self- addressed, stamped envelope. Sol LIbes POB 1192 Mountainside, NJ 07092 ■ BYTE's Bits RCA to Service Epson MX Printers RCA Service Company will provide nationwide war- ranty service for Epson America's MX series of micro- processor-based printers. RCA will also offer a wide variety of maintenance ser- vice packages to MX owners and users. Service will be per- formed by RCA technicians based in 180 locations throughout the U.S.B What's New? PUBLICATIONS Smart Ideas from Digital The fourth edition of Ideas (Index and Descrip- tion of Educational Appli- cation Software) lists more than 300 applica- tions packages for Digital Equipment Corporation's computer systems using the VAX/VMS and RSTS/E operating software. Soft- ware packages are alpha- betically listed by applica- tion under separate VAX/VMS and RSTS/E sec- tions. For your free copy, request publication num- ber EJ 19645-87 from Education Computer Sys- tems Group, Media Re- sponse Manager, PK3- 2/M94, 129 Parker St., Maynard, MA 01754. Circle 550 on inquiry card. Computerlst's First Aid Manual Perfect for those emer- gencies encountered by computer programmers, the Computerist's First Aid Manual gives detailed instructions for dealing with such maladies as "CRT Eye/' "Asteroids Wrist," and "Missile Com- mand Thumb." It also contains information for dealing with other com- mon home computing emergencies. The manual is available for $19.95 from Medi-Comp Inc., 70 Main St., Petersborrow, NH 03458. Circle R202 on inquiry card. Computer Graphics Vendor Directory The 1982 Directory of Computer Graphics Sup- pliers fists almost 300 ven- dors of hardware, soft- ware, systems, and ser- vices. The Directory con- tains key background in- formation on each com- pany's computer graphics products and services, complete with address, telephone number, and contact person. Among the subjects covered are computer-aided design and manufacturing, busi- ness graphics, animation, and image processing. Other features of the Directory include a com- puter-processed index that categorizes vendors by ap- plication and technologi- cal focus, technology studies and market re- ports, and a guide to computer-graphics semi- nars, conferences, and courses. For additional in- formation, contact Stanley Klein, Computer Graphics Directory, Suite 27, 730 Boston Post Rd., Sudbury, MA 01776. Circle 551 on inquiry card. Journal Probes Computers in Education The Journal of Com- puters in Mathematics and Science Teaching is a quarterly publication of the Association for Com- puters in Mathematics and Science Teaching (ACMST), a nonprofit professional organization. The journal explores such topics as "Computer-Based Meth- ods in Chemistry," "A Microcomputer-Assisted Presentation of Atomic Or- bits," and "Planning for Microcomputers in the Classroom." Other fea- tures of the journal include book reviews, a column on software resources, and a new products sec- tion. Annual ACMST mem- bership costs $7, which in- cludes a subscription to the journal. For additional details, contact ACMST, POB 4455, Austin, TX 78765, (5 I 2) 836-4378. Circle 552 on inquiry card. CP/M Software Catalog A catalog listing 50 volumes of low-cost, pub- lic-domain CP/M-based software is available from the Special Interest Group for Microcomputers (SIG/M). The complete 50- volume library, housed in single-density 8-inch disks, lists more than 900 pro- grams. The catalog costs $1.50 in the U.S. and Canada and $2.50 else- where. Contact SIG/M, POB 97, lsel\n t NJ 08830 t or call Bill Chin, (201) 778-5140, or Henry Kee, (212) 539-3202. Software Protection Report The various resources available for software pro- tection are explored in a 60-page manual from Communication Research Trade. The report explains the differences, advan- tages, and dangers of comparable security alter- natives. Information on trade secret protection, trademarks, and patents is included, and a major por- tion of the report is de- voted to copyright and in- fringement recourses, in addition, an example pro- gram demonstrating the proper display of a copy- right notice is provided. The report on software protection is available for $75 from Communication Research Trade, POB 3151, Redwood City, CA 94064. Circle 553 on inquiry card. Information Age Papers A compilation of papers presented in April 1 98 1 at the "Communications in the 21st Century" sym- posium has been pro- duced by John Wiley & Sons. In Communications in the 21st Century, 20 distinguished scientists, scholars, journalists, and business executives ex- plore such issues as the de- velopment of a national communications policy, business strategies for managing the information explosion, and the effects of technology on in- dividuals and institutions. Communications in the 2 1 st Century costs $ 1 9.95 April 1982 © BYTE Publications Ire 419 What's New? and is available from John Wiley & Sons Inc., One Wiley Dr., Somerset, NJ 08873, [20]} 469-4400. Circle 554 on inquiry card. wm^&WP* Test and Measurement Products Catalog A 432-page directory of test and measurement products is available from Metermaster, a company that represents nearly 40 manufacturers of test and measurement instruments. The catalog contains de- sign and performance specifications for meters, oscilloscopes, and other test and measurement in- struments. Product and test equipment categories are organized alphabet- ically according to manu- facturer. A glossary is also provided. The 1981/1982 Meter- master Catalog is avail- able free of charge to qualified engineers and buyers at Metermaster outlets, or you can write to Metermaster, 5646 Jill- son St., Los Angeles, CA 90040, (213) 685-4340. Requests must be sub- mitted on company letter- head. Circle 555 on inquiry card. 1 0,000 Components in Free Catalog Mouser Electronics' 128-page catalog of elec- tronic components con- tains full product specifica- tions, illustrations, and prices for more than ]0 r 000 items, ranging from clips and coils to potentiometers and plugs. The catalog is available free of charge from Mouser Electronics, 1 1433 Woodside Ave., Santee, CA 92071, (714) 449- 2220. Circle 556 on inquiry card. Catalog of Circuit Board Products A new 1 6-page catalog that describes products for circuit boards is available free from Pace Inc. Some of the products listed in the catalog are rework and repair boards, de- soldering and specialty systems, function acces- sories, and audio-visual training courses. Request catalog number 781 from Pace inc., 9893 Brewers Court, Laurel, MD 20707, (301) 490-9860. Circle 557 on inquiry card. SYSTEMS ADM-3 Upgrade Kit The lnterboard-3A Kit turns your Lear Siegler ADM-3 or -3A terminal in- to a microcomputer. The kit has a 4-MHz Z80 micro- processor with 64K bytes of memory and a floppy- disk controller that fits in- side the terminal. A single RS-232C and a Centronics- type parallel port allow peripherals to be attached. Options for the kit in- clude dual Tandon disk drives with 500K bytes to 2 megabytes of storage, and the CP/M operating system. The Interboard-3A Kit costs $795 and is avail- able from International Systems Marketing, 5161 River Rd., Building #2, Bethesda, MD 20816, (301) 986-0773. Circle 558 on inquiry card. Business BMC Computer's \f800 computer series is de- signed for medium-sized businesses and as an alter- native to multiuser, multi- tasking systems where a common database is un- necessary. The Z80-based \f800 computers are com- pletely integrated desktop work stations with a key- board, a printer, and a 1 2-inch high-resolution red/green/blue color dis- play. The \f800 series fea- tures 20 user-program- mable function keys, I/O slots supporting a multi- tude of interfaces, ROM cartridge, light pen, and a built-in printer with screen- print and list capabilities. The CP/M operating sys- tem and a color/graphics- Computers enhanced BASIC are stan- dard. Original equipment manufacturers have four \f800 models from which to choose, ranging in price from $4170 to $6570. Three models employ two built-in S'/Hnch disk drives for approximately 800K bytes of media storage; the fourth model has a single floppy-disk drive and a 5-megabyte Winchester hard-disk drive. Addi- tionally, two models carry a direct-connect modem and a selection of supplied software. For details, con- tact BMC Computer Corp., 860 East Walnut St., Car- son, CA 90746, (213) 323-2600. Circle 559 on inquiry card. 420 April 1982 © BYTE Publications Inc What's New? Single-Board Computer The SYM-2 single-board microcomputer incorpor- ates most features of the SYM-1, plus onboard power supply, choice of three microprocessors (6502, 6809, or 6802), cassette-interface jacks, eight toggle switches for user input, and eight light- emitting diodes for user output. Intended for office and industrial applications, the SYM-2 is software- compatible with SYM-I programs and firmware. The expansion and appli- cations ports are also com- patible with the SYM-1 , so expansion devices, such as random-access read/ write memory (RAM) or theFDC-l floppy-disk con- troller are fully inter- changeable between the two machines. The SYM-2 costs $249. For further details, contact Synertek Inc., Mail Stop 6 1 , POB 552, Santa Clara, CA 95052, (408) 988-5682. Circle 560 on inquiry card. Micromaster The Micromaster com- puter is a self-contained desktop unit from Barreto and Associates that oper- ates under a modified CP/M operating system. Designed for small- and in- termediate-sized busi- nesses, the IEEE S-100- based Micromaster has dual 8085 and 8088 pro- cessors and both a 5 '/4-inch, 5-megabyte Winchester hard-disk drive and 5 1/4 -inch, 96-track- per-inch, 500K-byte floppy-disk drive (addi- tional drives can be used). The Micromaster can oper- ate in either single-user or multiuser environments and its 12-inch video dis- play has an 80-character by 24-line format. The Micromaster is sup- plied with 64 K bytes of random-access read/write memory (RAM) that is ex- pandable to 16 mega- bytes, one parallel and one serial port, and a high- level language (BASIC or FORTRAN). The Micro- master is available for $ 12,500 from Barreto and Associates Inc., 507 West 16, Sedalia, MO 65301. Circle 561 on inquiry card. SOFTWARE TRS-80 Database Manager Adventure Interna- tional's Maxi Manager is a database manager for the TRS-80 Models I and III. It supports six different rela- tional search techniques and up to 20 user-defined fields of 40 characters each. Records can be up to 800 characters in length, and Maxi Manager has calculated equation fields plus a report gen- erator. Maxi Manager requires 48K bytes of RAM (ran- dom-access read/write memory) and one disk drive. The software is sup- plied with more than 1 80 pages of instructions and examples. Maxi Manger is available for $99.95 from Adventure International, POB 3435, Longwood, FL 32750, (305) 862-6917. Circle 562 on inquiry card. Keeping a Stiff Upper LISP A dialect of the LISP lan- guage, the Stiff Upper LISP has more than 120 built-in functions packed into 13K bytes. The user environ- ment includes symbolic break, trace, and single- stepping packages, plus an interaction history with REDOing facilities. Also provided are an extensible editor and an extensible online help facility, both of which are usable from within the LISP environ- ment. Upon initialization, the Stiff Upper LISP reads a file that enables the user to customize the environ- ment to personal prefer- ences. Other features in- clude screen control a program formatter, closures that maintain their own environments of procedures and data, both lexical and dynamic vari- able scoping, and tail recursion elimination by the interpreter where ap- propriate, which makes recursion as efficient as iteration. Stiff Upper LISP is avail- able, under the CP/M op- erating system, for $ 1 65 from Lifeboat Associates, 1651 Third Ave., New York, NY 10028, (212) 860-0300, Circle 563 on inquiry card. or, under TRSDOS, from Tennant and Tennant Computing, 353 7 Ridge -moor Dr., Garland, TX 75042,(214)530-0575. Circle 564 on inquiry card. 68000 Multiprocessor Operating System MTOS-68K is a real-time, multitasking, multiproces- sor operating system for the Motorola MC68000 microprocessor. A mod- ular system deisgned for high throughput, MTGS- 68K produces an assem- bly-language module that can be placed in ROM (read-only memory). It manages task coordina- tion, memory pools, input/ output, priority schedul- ing, interrupt processing, and multiple processors. The system runs on up to 16 separate processors that share a common memory. All processors are equivalent: there are no masters and no slaves. A single copy of MTOS- 68K executes on all pro- cessors. Without chang- ing application software, system performance can be improved by adding processors. Application software can be written in assembly language or \n a high-level language such as Pascal or C. MTOS-68K is distributed in assembly- language source-code form and is sold for a one-time license fee that permits the licensee to imbed the ob- ject program in his or her own products without fur- ther charge. For complete April 1982 © BYTE Publications Inc 421 What's New? details, contact Industrial Programming Inc., 100 Jericho Quadrangle, Jericho, NY I 1753, [516] 938-6600. Circle 565 on inquiry card. Two Atari Games Concom Enterprises has two new game programs for Atari 400/800 micro- computers. Both games are written in BASIC and machine language and feature fast action, sound effects, and high-resolu- tion color graphics. Each requires 1 6K bytes of RAM (random-access read/write memory). In Close En- counters, two players compete in a space battle, each trying to destroy the other's flying saucer. The game requires two joy- sticks. The second game, High Voltage, pits you against two killer robots. You are trapped in a field that's surrounded by a high-voltage fence and lit- tered with high-voltage obstacles- Strategy and speed are your keys to sur- vival. High Voltage re- quires a single joystick. Both games are avail- able on cassette for $15.95 each. For details, contact Concom Enter- prises, 2626 West Touhy, Chicago, IL 60645. CP/M-Compatible Utility Lifeboat Associates' Zap80 is a menu-driven 5'/4- and 8-inch disk ac- cess utility for SB-80 and other CP/M-80-compatible 8080/Z80 operating sys- tems. Zap80 automatically allows direct file viewing and patching by actual memory address. Zap80 is designed for experienced users and includes exten- sive file-utility servicing to access and patch file sec- tors, compare files, and so forth. For details, contact Lifeboat Associates, 1 65 1 Third Ave., New York, NY 10028, (212) 860-0300. Circle 566 on inquiry card. New Hashing Method Speeds Database Manager Micro Architect's IDM-X is a general-purpose inter- active database manager for the TRS-80 Model \l. The IDM-X features a built- in sort/merge package and a fast key-access method that uses a new hashing algorithm. IDM-X supports string, double-precision floating decimal, and in- teger variables. Other fea- tures include formatted numeric fields, using BASIC formats, and an ex- tensive report writer. The basic components of IDM-X are a database initialization program, a database manipulation program, the report writer, and a report generator. A dual-disk TRS-80 Model 11 with 64K bytes of memory is required. IDM-X costs $399; the user manual is available separately for $25. For additional infor- mation, request a product catalog from Micro Archi- tect Inc., 96 Dothan St., Arlington, MA 02174, (617) 643-4713. Circle 567 on inquiry card. CP/M-86 for the IBM Personal Computer Compuview's CP/M-86 (CP/M is a registered trade- mark of Digital Research) for the IBM Personal Com- puter includes an interac- tive line editor that permits cursor movement to the previous line and horizon- tal scrolling to a width of 162 characters, and emulation of terminals such as Televideo, the IBM 3101, and the Zenith Z- 19. Other features are an in- crease in disk capacity from the 160K bytes sup- ported by MS-DOS to 193K bytes; the ability to read and write many soft- sectored disk formats, in- cluding the Xerox 820's format; support for both serial and parallel printers; a disk formatter; a disk- copy program that makes a fast, "image" copy; the ability to set transmission rates for serial ports; and support of Tecmar's hard- disk drive and other pe- ripherals. For further information, contact Compuview, Suite 200, 1955 Pauline Blvd., Ann Arbor, Ml 48103, (313) 996-1299. Circle 568 on inquiry card. Slide Rule Simulator The Slide-Simulator transforms your TRS-80 Color Computer into a Mannehim-type slide rule. Using high-resolution graphics and controlled by the game paddles, the pro- gram simulates full log-log functions. A special ex- panded viewing option allows easy reading of the scales. The program is available on a 5 14 -inch floppy disk. For price infor- mation and a catalog of other innovative software, contact Abstract Mathe- matical Concepts Inc., 70 Main St., Putterboro, NH 03458. PERIPHERALS Keyboard Eases Word Processing A computer designed primarily to handle small- business applications is now available with a key- board dedicated to word processing. The new key- board is based on a Visual 200 computer terminal with electronic and me- chanical adaptations for Micropro's Wordstar word-processing system . The keyboard allows the user to strike a single color- coded key for center line, release or set margins, clearing or setting tabs, underscore, or any one of 24 other commonly used word-processing com- mands and cursor move- ments. The keyboard option is available on new Prodigy installations or as a field upgrade. For more details, contact Prodigy Systems Inc., 497 Lincoln High- way, Iselin, NJ 08830, (201) 283-2000. Circle 569 on inquiry card. 422 April 1982 © BYTE Publications Inc What's New? Versatile Robot Arm The Rhino XR-1 computer-controlled robot arm is a versatile, low-cost product for educational or light industrial use. The XR-1 can be run from a modem or any computer with an RS-232C port. Standing 32 inches high, the XR-I contains six motors, one for each axis point. It can reach up to 32 inches from base to fingertips; radial reach is 221/4 inches from the center of rotation to finger- tips. Waist resolution is 0.137 degrees; shoulder resolution is 0.076 degrees. The XR-l's lifting capability and gripping force are approximately 1 6 ounces. The Rhino XR-1 com- puter-controlled robot arm costs $2400. Contact Sandhu Machine Design Inc., 308 South State, Champaign, IL 61820, (217)352-8485, for further details. Circle 570 on inquiry card. Man-Machine Interface at Your Fingertips The 1 780A Infotouch Display screen is a 5- by 9-inch video-display screen with a touch-sen- sitive overlay. Messages, numbers, graphics, menus, switches, and special characters can be displayed through com- puter programming to guide an operator's re- sponse step by step. The Infotouch's screen displays 16 lines of 80 characters and features 60 definable touch-sense areas. The In- fotouch can be used with almost any desktop, home, or large computer. The 1780A Infotouch Display costs $1995. It's available from the John Fluke Manufacturing Co. Inc., POB C9090, Everett, WA 98206, (800) 426- 0361; in Washington, (206) 354-5400. Circle 571 on inquiry card. Apple III Hard-Disk Storage Corvus Systems has un- veiled new mass-storage units for the Apple HI com- puter based on high-capa- city 5- to 20-megabyte Winchester hard-disk sys- tems. The storage modules incorporate an intelligent controller, a proprietary controller, software, and an Apple III interface. Firm- ware for the intelligent controller supports fea- tures such as sector buffer- ing, automatic retries, diagnostics, transparent formatting with cyclic redundancy check (CRC) error detection, and high- speed data transfer using direct memory access (DMA) to random-access read/write memory (RAM) within the controller. The Apple HI Win- chester hard-disk mass- storage units range in price from S3750 to $6450. Contact Corvus Systems Inc., 2029 OToole Ave., San Jose, CA 95 1 3 1, (408) 946-7700, for additional information. Circle 572 on inquiry card. No More Grappling with Graphics The Grappler is a Centronics-compatible parallel interface board for the Apple ll It has on- board firmware to copy the Apple's high-resolu- tion graphics screen to a wide variety of printers, such as Anadex, Integral Data Systems, Centronics, and Epson. In the Grap- pler's standard printing mode, each white dot on the Apple's screen is printed as a black dot on paper. The inverse graph- ics mode allows you to print the reverse graphics of white-on-black. The double-size option doubles the graphics screen hori- zontally and vertically. Other features of the Grappler include word wrap-around, variable line and page length, 90- degree text rotation, the ability to skip over perfora- tion, and compatibility with the CP/M operating system and Apple Pascal. The Grappler is available at Apple dealers and com- puter stores for $ 1 75, in- cluding manual and inter- face cable. For complete information, contact Orange Micro Inc., Suite April 1982 © BYTE Publications Inc 423 What's New? G, 3150 East La Palma, Anaheim, CA 92806, (800) 854-8275; in Califor- nia, (714) 630-3322. Circle 573 on inquiry card. Apple II Button Pad A naval-operated nu- meric keypad is available from Hindsight Engineer- ing. Designed to plug directly into one of the Apple ll's slots, the keypad leaves your hands free for computer operation. (To insure proper interface, operate in a lint-free en- vironment.) The complete package includes the key- pad, interface card, con- necting cable, complete documentation, and in- structions on developing naval dexterity. The pack- age lists for S99.95. Hind- sight Engineering, FOB 107.5, Pizzaborough, NH 03458. Circle 1007 on inquiry card. Hard Disk for the ZX81 Responding to an obvi- ous need of ZX8 1 owners for more data storage space, Hindsight Engineer- ing has developed a 5-megabyte hard-disk sys- tem for the Sinclair ZX81. The system is available in either assembled or kit form. The kit includes in- structions for building your own clean room for kit assembly. A DOS will soon be available. For pric- ing information and a catalog of other products, write to Hindsight En- gineering, POB 107.5, Peanutbutter, NH 03458. Hfgh-Quaffty Low-Cost Terminal The WY- 100 is an in- telligent terminal offering an array of features nor- mally found in more ex- pensive products. The WY-1 00 exhibits ergo- nomic design with a de- tached keyboard and a tilt- able/rotatable display con- sole. It offers a data-valida- tion ability that ensures ac- curate keyboard entry and editing capabilities such as character insert and delete. Other standard fea- tures include word wrap, display features for forms creation, a split screen for viewing more than one data group simultaneous- ly, a separate I/O port for driving a printer, and an RS-232C port for host com- puter communications. The WY-1 00 costs $995. For complete de- tails, contact Wyse Tech- nology, 2184 Bering Dr., San Jose, CA 95 1 3 1 , (408) 946-3075. Circle 574 on inquiry card. 256K-byte Memory for IBM Zobex's 256K-byte RAM (random-access read/write memory) board with pari- ty is fully compatible with the IBM Personal Com- puter. The memory meets or exceeds IBM memory performance and requires only one expansion slot. The board contains a memory address-decoding scheme carried out by means of an onboard con- figuration switch that allows each 64K~byte seg- ment on the board to be either disabled or based at any 64K-byte boundary from to 1 megabyte. This allows the board to be used in conjunction with the IBM central processing unit board-mounted 64K- byte memory or mixed with IBM 64K-byte expan- sion boards. The 256K-byte memory board costs $998; original equipment manufacturer's discounts are available. Contact Zobex, 7343 J. Ronson Rd., San Diego, CA 92111, (714) 571- 6971. Circle 575 on inquiry card. Apple-Compatible Drives A. M. Electronics' 5 '/4-inch add-on disk drives are designed for "plug-and-go" compatibil- ity with the Apple com- puter. The drives are com- pletely compatible with Apple disk operating sys- tems and software, and offer 40 tracks of data storage and a 3-millisec- ond track-to-track access time. The add-on disk drives for the Apple, complete with case and cable, are available for $345. Con- tact A. M. Electronics Inc., 3366 Washtenaw Ave., Ann Arbor, Ml 48104, (313) 973-2312. Circle 576 on Inquiry card. Hard Copy from Video Terminals Axiom Corporation's Model EX- 1 650 printer can produce full-size hard- copy output directly from almost any video com- puter or graphics terminal, video monitor, or TV set. Entire pages of displayed data — even complex graphics, alphanumerics, foreign symbols, or hiero- glyphics—are rapidly re- produced on the printer. Paper width is 8/2 inches, which allows full-sized re- productions of forms, reports, and graphs. 424 April 1982 © BYTE Publications Inc What's New? The EX- 1 650 printer, with self-adjusting print- head, does not require ex- ternal hardware or soft- ware. A single connection to a standard video jack is the printer's sole require- ment. A smaller version of the printer, the EX-850, is available. The EX-850 ac- cepts paper 5/2 inches wide. The EX- 1650 costs $3495. Contact Axiom Corp., 1014 Griswold Ave., San Fernando, CA 91340, (213) 245-9244. Circle 577 on inquiry card. 5'/4-lnch Fixed Disk Drives The new SI series of 5/4 -inch fixed disk drives from Mitsubishi Electronics feature Winchester-design reliability. The SI series has a high-speed seek time of 75 microseconds (/*sj average, 160 fis max- imum, which includes set- tling time. Available with large storage capacities of 3.33, 6.66 to 10 mega- bytes (unformatted), each disk surface employs one movable head to service 160 data tracks. Further details and specifications can be obtained from Mitsubishi Electronics America Inc., Computer Peripherals Div., 2200 West Artesia Blvd., Comp- ton, CA 90220, (213) 979-6055. Circle 578 on inquiry card. Calendar/Clock for Small Computer The Hayes Stack Chronograph is an RS- 232C-compatible calen- dar/clock for small com- puters. The Chronograph reports time in hours, minutes, and seconds in 1 2- or 24-hour modes. The date is output in a year/month/day format with automatic adjust- ment for leap years. The Chronograph is indepen- dently powered, and has a battery backup to main- tain time, date, and week- day for up to one year when the power falls or is disconnected. Simple ASCII (American Standard Code for Infor- mation Interchange) char- acter strings let the user set, read, and display calendar/clock data, con- trol the computer alarm, and select various options. A complete Chrono- graph system costs $249. Contact Hayes Microcom- puter Products Inc., 5835 Peachtree Corners E., Nor- cross, GA 30092, (404) 449-8791. Circle 579 on inquiry card. S-100 Bus for Superbrain The SBS-I00A Interface Adaptor provides the nec- essary components for converting the Superbrain microcomputer to S- 1 00 bus operations. The unit can be fitted within the Superbrain cabinet to con- trol a single S- 1 00 board or it can be mounted exter- nally in an S-100 box for control over a number of S-100 boards. The SBS-I00A Interface Adaptor board costs S595, including postage but ex- cluding duty fees. For fur- ther details, contact Icarus Computer Systems Ltd., Deane House, 27 Green- wood Pl, f London NW5 INN, England, 01-485 5574. Circle 580 on inquiry card. Tape Backup Fit for a Chieftain If you own a Chieftain or Pathfinder system from Smoke Signal Broadcast- ing, you can now have a tape-streamer backup as an option for your 5 '/4- or 8-inch Winchester hard- disk system. The tape streamer can store up to 20 megabytes on 14 -inch cartridge tape. With a tape streamer, computer sys- tems can transfer up to 20 megabytes of data in less than five minutes at 90 inches per second. The Chieftain and Pathfinder systems also incorporate two means of backup with the streaming-tape drive: file-by-file or a com- plete backup with a single command. Drive-to-tape and tape-to-drive data transfers are provided. The tape streamer is available as a standard option to any Chieftain or Pathfinder Winchester disk-drive system for $1500. Also available are tape-streamer options for Smoke Signal Broadcasting models 98W10, 98W30, and 98W15T20. Contact your local Smoke Signal dealer or Deborah Con- rad, Smoke Signal Broad- casting, 31336 Via Col- inas, Westlake Village, CA 91362, (213) 889-9340. Circle 581 on inquiry card. New Winchester Disk Series The Pyxis Series of 5!/4-inch Winchester disk drives range from 4 to 1 6 megabytes of unformatted storage capacity. The series is available in four models: the Model 4, a single-disk device with 4 megabytes of storage; the Model 8, a two-disk device with 8 megabytes; the Model 12, a three-disk device with 12 mega- bytes; and the Model 16, a four-disk device with 16 megabytes of unformatted storage. The Pyxis series interface, form factor, mounting, and power re- quirements are all com- April 1982 © BYTE Publications Inc 425 What's New? patible with 5 l A~inch Winchester-technology in- dustry standards. in original equipment manufacturer quantities, the Pyxis series ranges in price from $740 (Model 4) to $1290 (Model 16). For details, contact Ampex Corp., Memory Products Division, 200 North Nash St., El Segundo, CA 90245, \2\3) 640-0150. Circle 582 on inquiry card. MISCELLANEOUS \j^ £-"•/ New Products Clean Circuit Boards Two new products from Texwipe can help keep your printed-circuit boards clean. The first, Gold- Wipes, provides a con- venient method to clean and protect the gold fingers and other metallic surfaces on printed-circuit boards. Gold-Wipes are in- dividually foil-wrapped pads that are presaturated with cleaning and lubricat- ing agents. Use of Gold- Wipes can cut down on adhesion, brittle fracture, and abrasion problems. The second product, D-Flux, is a cleaning sol- vent and brush for dislodg- ing stubborn fluxes from printed-circuit boards. D-Flux's applicator dis- penses a controlled amount of solvent, while the brush scrubs off flux. It is designed for use on board repairs, assembly operations, and other en- vironments that require flux removal. Both products are avail- able directly from the man- ufacturer, Texwipe Co., Sales Office, POB575, Up- per Saddle River, NJ 07458, (201) 327-5577. Free samples and literature are available upon re- quest. Circle 583 on inquiry card. Dynamic-Memory Board for S-T00 Systems Systems Group's new 1 28K-byte dynamic-mem- ory board is fully compati- ble with most S-100-based microcomputer systems, including Alpha-Micro, North Star, and Dynabyte. The board has eight inde- pendent 1 6K-byte soft- ware-selectable memory banks, each addressable on any 16K-byte bound- ary. Other features include parity for single-bit error detection, 10 onboard diagnostic LEDs (light- emitting diodes), 4-MHz Z80 operation using trans- parent refresh, and full compliance with IEEE tim- ing specifications with 20-megabyte extended addressing. The dynamic- memory board's power re- quirement is 8 watts max- imum. Contact Systems Group, 1601 Orange- wood Ave., Orange, CA 92668, (714) 633-4460. Circle 584 on inquiry card. Dual RAM Board for Apple II RAMPIus+ is a new dual 16K-byte RAM (ran- dom-access read/write memory) card for the Apple li Two banks of 16K-byte selectable RAM expand the Apple II to 80K bytes of available memory. The second bank of RAM is controlled by user-sup- plied software. Hardware and software selection of each 16K-byte bank of RAM is user-controlled. The card also supplies its own refresh circuitry. RAMPIus-h can be in- stalled in any slot on the Apple and does not re- quire cables or the removal of integrated cir- cuits from the Apple motherboard. When RAMPIus+ is in slot 0, it emulates the Apple Lan- guage Card. Multiple RAMPIus-i- cards can be installed into the same Apple 11. RAMPIus+ is supplied with 1 6K bytes of installed RAM for $189. The addi- tional 16K-byte plug-in RAM costs $24.95. RAM diagnostics on disk are in- cluded. For details, contact Mountain Computer Inc., 300 El Pueblo Rd., Scotts Valley, CA 95066, (408) 438-6650. Circle 585 on inquiry card. Erase-Only The Stanislowski Elec- tronics 3131.3 is a 4 K- byte, vigorous random- access erase-only memory (RAEOM) Imaginary Metal Oxide Semiconductor (IMOS) integrated circuit (IC). Packaged in a nonstandard 27-pin dual inline package (DIP), the 3131.3 RAEOMIMOSfC has six erasing modes for maximum versatility and is designed for all applica- tions requiring an erase- only memory (EOM). Pos- sible applications include disposing of obsolete data and programs, destroying Memory incriminating evidence, and amusing computer hobbyists. Due to the patented IMOS process, the 3131.3 remains fully functional even when power is re- moved, making it ideal for use during power black- outs. The 3131.3 is priced at $0.59 (more or less) in OEM (optional ephemeral merchandise) quantities. Contact GIGO Enterprises, 70 Main St., St. Peterborough, NH 03458. 426 April 1982 © BYTE Publications Inc What's New? Adjustable Video Monitor Platform Structural Concepts' new portable, swiveling, tilting, sliding video- monitor platform helps make any desk or tabletop economically safe. The platform tilts 20 degrees up or down from a hori- zontal position for glare reduction and operator comfort and can swivel a full 360 degrees for shared or angled usage. Addition- ally, it can slide up to 8 inches frontwards or back- wards, which can help re- duce eye strain. The video-monitor plat- form is available in a varie- ty of sizes for most video monitors. Mounting hard- ware is not required. Con- tact Structural Concepts Corp., 17237 Van Wagoner Rd., Spring Lake, Ml 49465, (800) 253- 5102; in Michigan, (616) 846-3300. Circle 586 on inquiry card. Memory Management for the TRS-80 Model III The Compactors I and IV are the first products in a series of add-on units for Radio Shack's TRS-80 Model III from Hurricane Laboratories. The Com- pactor I allows the TRS-80 to run CP/M applications and utility programs with- out altering the TRS-80's operating environment. When installed in the Model III, you can elect to use CP/M version 2.2, TRSDOS, TRS-BASIC, or Hurricane Laboratories' Z80 Diagnostic Monitor, which is a CP/M program- ming tool. The Compactor IV gives the TRS-80 Model III an 80-character by 24-\\ne video-display screen and provides an RS-232C serial interface. The Compactor IV lets you use the Model III as a stand-alone com- puter or as an intelligent terminal to a larger host computer system. The Compactors I and IV cost $450 and $475, re- spectively. Contact Hurri- cane Laboratories Inc., POB 631, Cupertino, CA 95015, (408) 446-0777. Circle 587 on inquiry card. Cables Feature Both Male and Female Connectors Computer System Asso- ciates' RS-232C cable sets have both male and fe- male DB-25 connectors at- tached at each end. This approach eliminates the problem of having the wrong connector for a ter- minal, video-display de- vice, or computer. Stock- ing one type of cable will satisfy all data cable re- quirements. Prices begin at $50. Contact Computer System Associates, 7562 Trade St., San Diego, CA 92121, (714) 566-3911. Circle 588 on inquiry card. High-Capacity Memory Board for IBM Personal Computer Datamac Computer Systems' new high-capaci- ty memory expansion board for the IBM Personal Computer lets you easily upgrade to 544K bytes of memory. The expansion board can be configured in a variety of sizes from 64K bytes to 256K bytes- all with parity. The 64K-byte board is available for $499. For fur- ther details, contact Robert Lindgren, Datamac Com- puter Systems, 680 Alma- nor Ave., Sunnyvale, CA 94086 (408) 735-0323. Circle 589 on inquiry card. Radio Ratings Analysis Recall is a software package that helps radio stations quickly organize and interpret data fur- nished by a major radio- station ratings service. De- signed to be used with the Apple 11 microcomputer, Recall can analyze up to four radio stations or four rating books simultane- ously. It displays full-color graphics and provides ex- tensive printouts. Different sections of Recall can pro- vide in-depth information on radio-audience flow dynamics, daypart recy- cling, and market position- ing. The Recall package costs $750, which in- cludes a 100-page manual and support consultation. Contact Media Service Concepts, 1713 N. North Park Ave., Chicago, 11 60614, (312) 951-2680. Circle 590 on inquiry card. 256K-Byte RAM for the S- 100 The Superam 50 RAM (random-access read/write memory) board provides 256K bytes of RAM and is compatible with the IEEE-696 S-I00 bus stan- dard. The board can be configured for either bank- select or extended address- ing. Bank-select offers 64K-byte banks for mem- ory-protect applications, and each bank can be in- dividually set to any 64K-byte block of the 256K-byte address space. Extended addressing allows memory placement at any 256K-byte boun- dary segment in a 1 6-megabyte address field. A parity bit feature that detects single-bit errors per byte is included with the Superam. The Superam 50 is avail- able in two speeds: the Superam 50-P with a 2 75-nanosecond max- imum access time and the Superam 50-AP with a 225-nanosecond max- imum access time. In ori- ginal equipment manufac- turer's quantities, the Superam 50-P costs $ 1300 and the 50-AP costs $ 1 400. Contact Piiceon Inc., 2350 Bering Dr., San Jose, CA 95131, (408) 946-8030. Circle 591 on inquiry card. April 1982 © BYTE Publications lnc 427 Circle 101 on Inquiry card. APPLE pjP S-100 PRINTERS — IN STOCK MX-80 $ 470.00 MX-80FT MX-iOO 750.00 NEC8023A DISK DRIVES — 5%" Add on for Apple (made by Tandom) Apple Disk w/controller (made by Tandom) MPI-B51 -Sgl/Dbl Tandom— Sgl/Dbl SA400 — Sgl/Dbl DISK DRIVES — 8" Shugart80lR — Sgl/Dbl OumeDT-8 — Dbl/Dbl - DISK PACKAGES 2-801 R Cabinet Power Supply 2-DT-8CabinetPowerSupply ... Cabinet Power Supply Ail Assembled and Tested 9i0Teievideo 950Televideo TERMINALS $ 599.00 920Televideo 919.00 Addsviewpotnt SINGLE CABINETS Pwrsply8" $ 200.00 PwrSplySVo" . . . MONITORS NEC-JB1201 Amdek color 1 Zen ith.Creen screen we carry much, much more, call .$ 590.00 . 525.00 $ 370.00 . 485.00 . 250.00 . 230.00 . 250.00 $ 390.00 500.00 $1100.00 1300.00 300.00 .$ 740.00 570.00 $ 90.00 $ 199.00 . 400.00 . 125.00 Computer Components Unlimited lUTer ORDER DESK CALL IDOnentS (213)604-3311 kzxLm Send MaH Order- VISA / MC, HimiteCl Check, Wire Transfer P.O. Box 1936 / Hawthorne, CA 90250 AIM for Control For process control or in- dustrial development systems, put Rockwell's AIM 65 to work for j§ you. Use off- the- % shelf AIM-Mate Series and STD BUS expansion prod- ucts to configure the sys tern you need. The AIM 65 includes: typewriter, alpha- numeric LED display, and fast thermal printer. Plug-in options include: memory (to 48K), ROM languages, parity protection, video display, floppy disk storage, STD BUS expansion cage, TTL and real world interfaces, and complete system soft- ware. Call or write for complete AIM-Mate Series infor- mation. ^FORETHOUGHT •PRODUCTS 87070 Dukhobar Road, Eugene, Oregon 97402 (503) 485-8575 What's New? Jon Swanson, staff drafting editor, irons out a few problems in his largest schematic. Debugging Tool Irons Out Circuit Problems The General Electric Model F340 Electric Iron serves as a handy debug- ging tool for crucial logic circuits that must exhibit planar topology or use especially thin-film sub- strates. Using the latest de- ion ized- vapor-injection technology, the Model F340 can be used with cir- cuits arrayed on fiber sub- strates up to 0. 1 cm (ap- proximately 1/8 inch) thick, assuming proper ad- justments for duration of treatment. Contact General Electric Company, Housewares and Audio Business Divi- sion, FOB 5105Y, Hillside Station, Bridgeport, CT 06602. ■ Where Do New Products Items Come From? The information printed in the new products pages of BYTE is obtained from "new product" or "press release" copy sent by the promoters of new products. If in our judgment the information might be of interest to the personal computing experimenters and homebrewers who read BYTE, we print it in some form. We openly solicit releases and photos from manufacturers and sup- pliers to this marketplace. The information is printed more or less as a first-in first-out queue, subject to occasional priority modifica- tions. While we would not knowingly print untrue or inaccurate data, or data from unreliable companies, our capacity to evaluate the products and companies appearing in the "What's New?" feature is necessarily limited. We therefore cannot be responsible for product quality or company performance. 428 April 1982 © BYTE Publications Inc Circle 179 on inquiry card. Conducted by Steve Ciarcia VIA Experiment Board Dear Steve, I need an I/O (input /out- put) experiment board that I can plug directly into an Apple II Plus I/O slot. For my purposes, the board must use a Rockwell 6522 VIA (versatile interface adapter). Do you have a schematic diagram of such a board, or do you know of a company or a person that has made one? Everest McDade Arden, NC This interface has gen- erated a lot of discussion, going back to the November 20, 1977, EDN magazine arti- cle "EDN System Design Project." The biggest prob- lem with the interface seems to be the "bogus" timing of the phase 2 signal on the Apple II bus. By running the phase signal through two 4050 CMOS (complementary metal-oxide semiconductor) gates in series, the correct phase timing can be achieved. (You can also try adding an 820-ohm resistor and a 56-picofarad capacitor because this will generate an additional 30-nanosecond delay, which should work as well.) The VlA's CS2 signal is then connected to the I/O select signal on the bus. This should solve your problem. You may also be interested in Kenneth Ciszewski's article "Add a Peripheral Interface Adapter to Your Apple II" (lanuary 1982 BYTE, page 324). . . . Steve Bus Standard Stops Here Dear Steve, For several months, some manufacturers were claiming that their product was "com- patible with the proposed IEEE S-100 bus standard." Recently I noticed that the wording has changed to ". . . conforms to the IEEE-696 S-100 Standard." From this I infer that the "proposed standard" is now a bona fide standard. Where can I get a copy? Paul Frost Beaverton, OR EDN magazine recently featured an article on various bus standards, including the IEEE-696 S-100 bus standard. The article, "Compare (jlC- Bus Specs to Find the Bus You Need, " by Carl Warren, (EDN, June 10, 1981, page 141), contained a complete definition of the S-100 bus. For a copy of the standard, contact Howard Fullmer, Chairman IEEE-696 Commit- tee, Parasitic Engineering, FOB 6314, Albany, CA 94706, (415) 839-2636. . . .Steve Totem Poles and TTL Dear Steve, I have a couple of ques- tions about TTL (transistor- transistor logic). What is the difference between totem- pole and open-collector out- puts? And what is an expand- able gate? Many thanks! M. A. M. Felt Amsterdam, Netherlands Totem-pole output on a TTL integrated circuit con- sists of two transistors essen- tially in series, one above the other (see figure 1). In the high output state, the top transistor conducts, so the output is greater than 2.4 volts (V). In the low output state, the bottom transistor conducts, so the output is less than 0.8 V. During the transition be- tween states, both transistors are conducting, and large current spikes are induced in the power supply. If not properly bypassed, these transient spikes may trigger other circuits. If a full 5 V are needed during the high state, a pull-up resistor can be used as shown in figure 2. Open-collector output cir- cuits replace the top tran- sistor and diode of the totem pole with an external pull-up resistor (figure 3). These out- puts can then be tied together as in a "wired-NOR" circuit or where an output high volt- age greater than 5 V is desired. However, they are noisier and slower than totem-pole outputs. Tying totem-pole outputs together usually means cata- strophic results as each tries to pull the other high or low. Expanders and gate ex- panders are TTL devices that allow the expansion of some logic functions. For example, they would be used if a 32-input AND gate were needed. They are not very popular today. . . .Steve Figure 1 + 5V Figure 2 + 5V Figure 3 + 5V EXTERNAL . PULL-UP " RESISTOR -o OUTPUT + 5V r—^, OUTPUT April 1982 © BYTE Publications Inc 429 Circle 105 on inquiry card. MAIL ORDER DISCOUNTS flgappkz // SOFTWARE & ACCESSORIES PRINTERS VfSICALC 169 VISITREND/VISfPLOT 215 VISIFILE :,, .210 Epson DESKTOP PLAN II BPI BUSINESS SOFTWARE CONTINENTAL BUS. SOFTWARE SUPERSCRIBE II SUPERTEXTII EASYWRITER WORDSTAR (CP/M) REAL ESTATE ANALYZER TAX PREPARER CREATIVE FINANCING . . . 120 HAYES MiCROMODEM II 299 MICROSOFT 2-80 SOFTCARD 299 MICROSOFT 16K RAM CARD 169 VIDEX 80 COLUMN CARD 269 159 335 215 110 125 219 299 120 85 ..350 .460 .560 .760 2499 EPSON MX-70 . EPSON MX-80 . EPSON MX-80FT . . . EPSON MX-100 QUME SPRINT 5/45. MONITORS AMDEX LOW-RES 13" COLOR I 369 AMDEX HI-RES 13" COLOR II 850 SANY09"B&W 185 ZENITH 12" GREEN 125 NEC 12" GREEN 169 NEC 12" LOW-RES COLOR 365 NEC 12" HI-RES RGB COLOR 875 NEC PC-8000 NEC ATARI 800 & 400 A ATARI' ATARI 800 (16K). . .749 ATARI 400 (16K) 349 810 DISK DRIVE 439 16K RAM MEMORY MODULE 89 850 INTERFACE MODULE 159 830 ACOUSTIC MODEM 159 ATARI WORD PROCESSOR 125 XEROX 820 "SAM" SYSTEM I (5V4 " DRIVES) 2395 SYSTEM II (8" DRIVES) 3050 XEROX 630 PRINTER 2325 WORD PROCESSING (WORDSTAR) 425 CP/M OPERATING SYSTEM 175 TO ORDER: Please send cashier's check, money order or personal check (allow 10 business days to clear). VISA and Master Card credit card service add 3%. American Express credit card service add 5%. Shipping, handling and insurance in U.S. add 3% (minimum $5). California residents add 6% sales tax. Foreign orders add 10% for shipping. Equipment is subject to price change and availability. All equipment carries factory warranty. TELEX: 697120 DATAMAX-SDG COMPUTER HORIZON 16766 Bernardo Center Drive, Suite 110B, San Diego, CA 92128 (714)565-7092 (800)854-1941 PC-8001 A SYSTEM W/32K CALL PC-8012A I/O & EXPANSION SLOTS W/32K . CALL PC-8031A DUAL DRIVES CALL PC-8023A MATRIX PRINTER TRACTOR/FRICTION CALL JC-1202DH HI-RES, COLOR MON CALL THE WEDGE-DISK. RS232 & GAME I/O W/32K CALL DISKETTES BASF SVk " DISKETTES (10) 25 BASF 8" DISKETTES (10) 29 DRV COMPUTERS LTD. FLOPPY DISK DRIVE SYSTEMS CANADA'S No. 1 DISK DRIVE CENTRE APPLE & ATARI 40 and 80 Trk Drives with supporting software Apple Disk Drives from $550 and up Personal Computer Users— TRS80 MP1 Drive 51 with power supply & case Can. $475 Can. $250 Can. $1,550 Percom Doubler If Model III 2-Drive Internal Kit Authorized Percom & Trak Dealer and Service Centre DM/ COMPUTERS LTD. 15100 -40th AVE, SURREY, B.C., CANADA V3S 4N7 (604) 576-8535 Ask BYTE. Controlling Heat and Surges Dear Steve, I have two problems that I don't believe you have covered. First, in the Tampa/ St. Petersburg area, which suffers from power-line noise due to lightning, BSR X-10 control units are often trig- gered by line surges. It is not really a good idea to leave the X-10 energized during an ex- tended absence. To come home and find the TV, radio, or lights on when they should be off is not too good. This problem probably has an electronic solution. Second, the TRS-80 Model I is not really designed for 24-hour continuous opera- tion insofar as heat is con- cerned. To be sure, you can take the two power supplies out of the Expansion Inter- face, but even that is prob- ably not enough. This prob- lem requires a hardware solu- tion, which may be easy once the necessary ventilation is determined. R. M. Sanford Largo, FL According to reports, BSR X-10 control modules have been tripped by power-line transients. 1 have not had this problem in my area, so I'm unable to experiment with a fix. A metal-oxide varistor (MOV) across each module would help because they would clip the voltage surge at approximately 130 volts. These units are made by Gen- eral Electric and are available from major industrial parts suppliers. You didn't mention whether you were having problems with your TRS-80 because of heat or whether it simply gets hot. The easiest way to cure heat problems is to use a fan for some forced ventilation. This also avoids having to open the box. Placing larger heat sinks on the power tran- sistors will draw off even more heat, but unless the heat can be carried away, nothing is to be gained by this approach. Small fans are available from many sources, including Radio Shack. Remember to keep the fan motor away from any magnetic media such as disks or tapes. . . . Steve You Get What You Pay For Dear Steve, I have a Commodore VIC-20 computer and I would like to get more char- acters per line. If it is pos- sible, how do I go about do- ing it? Do I have to add or replace any hardware? Itshak Mihaeli Brooklyn, NY For less than $300, the VIC-20 represents a good value. In designing a com- puter for that price range, however, some compromises had to be made. One such compromise, as you know, is the screen-display format of 23 lines of 22 characters. The display is memory-mapped (i.e., a certain portion of memory is set aside solely for the screen), so modifying this requires changing both the hardware and the software. Even the VICs 176 by 176 high-resolution option will not allow any more charac- ters, although different shapes are available under software control. A comparison of the VIC-20 with four other low- cost microcomputers ap- peared in the May 1981 BYTE (see page 46). The article, "The Commodore VIC-20 Microcomputer, A Low- Cost, High-Performance Consumer Computer, " by Gregg Williams, featured a chart that showed the VIC-20 to be quite comparable to its competition. . . .Steve 430 April 1982 © BYTE Publications Inc Circle 153 on inquiry card. Sweet Talker Interface Dear Steve, I'm interested in interfacing the Sweet Talker speech syn- thesizer to my Commodore 4032N computer. (See "Build an Unlimited-Vocabulary Speech Synthesizer/' Septem- ber 1981 BYTE, page 38.) Commodore has made a bunch of machines, but vir- tually all of them have the parallel user's port, also called the VIA (versatile interface adapter) port. The lower 12 pins on the edge connector go to a MOS Technology 6522 VIA and consist of two grounds, eight data lines, a CA1 (an input) handshake line, and a CB2 line (described as "a very powerful connection that has most of the abilities of CAl but can also act as the input of the VIA shift register"). I know how to program any byte onto the data lines I want, but Commodore is silent about using these "handshake" lines. Can I use one line to sense when it's time to deliver the next phoneme code, and the other to strobe the Sweet Talker once the phoneme is present? Since Apple Computer already has the interface on one model, I'm hoping that a PET/CBM interface will be very similar. Is a ready- made, interfaced PET/CBM version forthcoming? If not, I'd appreciate any help on do- ing it myself. Larry Hatch Menlo Park, CA The 6522 VIA used in the PET computer is very power- ful and versatile; however, a great deal of explanation is required to fully use its fea- tures. I strongly suggest that you get a copy of the 6522 Data Sheets and a 6500 Series Hardware Manual for a com- plete explanation as well as some applications. Both are available from MOS Tech- nology Inc., 950 Rittenhouse Rd., Norristown, PA 19403, (800) 345-6386; in Penn- sylvania, (215) 666-7950, ask for marketing. Handshaking lines CAl and CB2 can control the Sweet Talker, but the proper control word must be written into address location hexa- decimal E84C, the peripheral control register. My "Circuit Cellar" article described the necessary programming for the Sweet Talker. This should solve your interface problem. . . .Steve Variable Errors Dear Steve, I own an Apple II complete with disk drives, Language card, Silentype printer, Videx 80-column video-display card, and Microsoft Softcard with a Z80 microprocessor. I've tried a couple of your machine-language programs, and although I didn't under- stand them, they work beautifully. I wrote this sim- ple BASIC program: 10 a= 2 20 A= 3 30 Q = a * A 40 Print Q but I got a syntax error in line 10. In my engineering pro- gram, I must use lowercase variables. H. J. Baerwolf Inglewood, CA Applesoft BASIC does not recognize lowercase vari- ables, which is why you got the syntax error. The May 1980 Micro, The 6502/6809 Journal has an article that should solve your problem. (Contact Micro Ink Inc., 34 Chelmsford Ave. , POB 6502, Chelmsford, MA 01824, (617)256-5515.) The program not only handles lowercase variables but it takes care of punctuation, too. . . .Steve Strain-Gage Data Collection Dear Steve, I recently read your BYTE articles on the Z8-BASIC microcomputer. (See "Build a Z8-Based Control Computer with BASIC, Part 1," July 1981 BYTE, page 38; "Part 2," August 1981 BYTE, page 50. ) My company is in- terested in using the Z8 in the field of strain-gage data col- lection. For this application, we would also need an A/D (analog-to-digital) converter of the type used in your se- cond article. Where can we obtain additional informa- tion on the ADC0808 A/D converter shown in figure 2 (August 1981 BYTE, page 66)? G. F. Fornaro United States Pipe and Foundry Co. Birmingham, AL The Z8-BASIC microcom- puter is an excellent choice for strain-gage applications. The ADC0808 is available from National Semiconduc- tor Corp., 2900 Semiconduc- tor Dr., Santa Clara, CA 95051, (408) 737-5000. . . .Steve ■ In "Ask BYTE," Steve Gar- cia answers questions on any area of microcomput- ing. The most representative questions received each month will be answered and published. Do you have a nagging problem? Send your inquiry to: Ask BYTE c/o Steve Ciarcia POB 582 Glastonbury CT 06033 If you are a subscriber to The Source, send your ques- tions by electronic mail or chat with Steve (TCE317J directly. Due to the high volume of inquiries, per- sonal replies cannot be given. Be sure to include "Ask BYTE" in the address. Minimum 24K • Single density • Soft sector • Single side Converted to run under CP/M by Russ Wetmore Dealer Inquiries Invited Adventure International • Box 3435 • Longwood, FL 32750 TOLL-FREE ORDER NUMBER: (800) 327-7172 IN FIORIDA<30S)M2B»I7 PING ANO HANOLISG CHARGES ARE EXT HA *r.es ARE iueJtCl Circle 13 on inquiry card. April 1982 © BYTE Publications Inc 431 Programming Quickies A BASIC Program for Home Cryptography Ralph Roberts POB 8549 Asheville, NC 28814 The study of codes and cryptograms has always fascinated me, and it takes little imagination to see the power of the personal computer applied to this field. I used cryptographic devices during Army service in the late sixties but now find that my Smoke Signal Chieftain is capable of encoding and decoding at a level much greater than the military devices I once used. That's 'clear text" to me. I devised the program shown in listing 1 as a first ex- periment in computerized encrypting. Much elaboration is possible, but this program may provide a starting point for you as well. The program is written in Computer- ware's version 6.0 BASIC but should run in most stan- dard B ASICs with minimal changes. If you don't have a disk drive, use data statements or read in the text one line at a time. Listing 1: An encoding and decoding program in Computerware's version 6.0 BASIC. The POKE statement at line 10 changes the BASIC'S delimiter character from a comma to an end-of-line character to improve handling of commas in text. * 0001 0002 0010 0020 0030 0040 0050 0060 0070 0080 0090 0100 0110 0120 0130 0140 0150 0160 0170 0180 0190 0200 0210 0220 0230 0240 0250 0260 0270 0280 REM ;:. ENCODING, DECODING PROGRAM ::: REM : : : by Ralph Roberts :;:;::;::::.: POKE( 210,13) STRING= 124; LINE=100 ; PRINT . PRINT PRINT TAB( 25 ), "ENCODING PROGRAM" ; PRINT ; PRINT INPUT "Password" ,P$ :GOSUB 24U INPUT "Encoding or Decoding (1 or 2 ) " , I PRINT :IF 1=1 INPUT"Name of file to be ENCODED" ,A$ IF 1=2 INPUT"Name of File to be DECODED" ,A$ IF 1=2 LET A=A*(-1) INPUT "Name of file to receive 'doctored' output" ,C$ OPEN #l,A$:OPEN #2 ,C$ READ #1 ,B$ IF B$ = " ,, THEN 230 FOR X = l TO LEN(B$) LET B=ASC(MID$(B$ ,X,1) ) IF 1=1 LET B=B+A;IF B>123 LET B=(B-123)+32 IF 1=2 LET B=B+A;IF B<32 LET B=(B+123)-32 LET D$=D$+CHR$(B) NEXT X:IF 1=1 LET A=A+1;IF A=124 LET A=l IF 1=2 LET A=A-1:IF A=-124 LET A=-l PRINT ; PRINT B$; PRINT D$ WRITE #2,D$;D$="";B$="" GOTO 110 POKE( 210,44) ; CLOSE #1: CLOSE #2: END LET P=LEN(P$) FOR X=l TO LEN(P$) LET P1=P1+ASC(MID$(P$,X,1) ) :NEXT X LET A=INT(P1/P) . IF A>123 PRINT"Sorry, PASSWORD phrase too big":RUN RETURN 432 April 1982 © BYTE Publications Inc For those of you who need a practical use for this pro- gram before reading further, I'll offer this example. If you work with a multiuser system, say in a college or high school, you could store your deep, dark secrets in a for- mat that no one else could decode. Those of us who don't have deep, dark secrets encode just for the fun of it (or so we'd like you to think). Writing of secrets, I do have one little trick to make this encoding program work more conveniently. In line 10 of listing 1, the POKE statement changes the delimiter character in my BASIC from a comma to an end-of-line (EOL) character. This allows the program to process an entire line in a text file, including commas. If your manual conceals the location of the delimiter character (as mine did), it's easy to concoct a four- or five-line PEEK, POKE routine that will find the location for you. Just successively change each comma in memory (decimal 44) to the EOL character (decimal 13). After each change, Listing 2: An encoding run of the encoding-decoding program shown in listing 1. ENCODING PROGRAM Password ? THE RAIN IN SPAIN FALLS MAINLY ON THE PLAIN Encoding or Decoding (1 or 2) ? 1 Name of file to be ENCODED ? SECRET. MSG Name of file to receive 'doctored' output ? SECRET. X9 TO: CIA HEADQUARTERS — LANGLEY, VIRGINIA FROM: SECRET AGENT X9 1/2. <7"c+l)c0-) ,9=) ;<-. , cppc4)6/4-Aoc>l:/161)ccc.:7 5 n c;-+;-+3. ,=#d,5*7-.<=27 .d.7=,Bd27=8d, .9>+52 , d8/d68 5-*?2* TO OBTAIN PLANS ON SECRET 'BOOlM-BOOM 1 MISSLE. eeeeeeeee>9e9,>+38e;6 + 8 = e98e=/-el,997r,9 971e7 3 = ==6/s Hi guys. Having wonderful time in Moldavia. Am sending you all f ffff3TfR d©tf3LaTYRfbZYGP]Q°Wf JTXPfTYf8ZWOLaTLtf ,Xf©PYOTYRf dZ° f LWW this via courier bat. Hope she got through. °TU_gbUMgO[a©UQ£>gNM°ug4 [^>Qg JTQgS [ °g°T^ [aSTu # Went by the secret research facility on the outscirts of Moldavia City hhhhhDR [ ahOf haURh° RP_Rah_R° RN_PUhSNPVYVaf h© [ haURh©ba° PV_a° h® Sh : ©YQNcVNhO Va f and had no trouble buying the blueprints for the dreaded 'boom-boom 1 0®RiVORi@] ib°] cPZSiPcgW®UibVSiPZcS©°W®baiTj ° ibVSiR SORSRipP] ] [vP] ] [p missile. They had a concession stand out front selling that and other ®XbbX[TxjCWThjWPSjPjR©] RTbbX©] jbcP] Sj©dcjUa©] cjbT [ [X] V jcWPc j P] Sj^cWTa plans. I'll bring them back in my bootheel. Need anything else? (sgnd) X9 1/2. °©Q^cyk9r®®kRbY©WkdXU]kRQS[kY©k] ikR dXUU®yk>UUTkQ^idXY^WkU©cU/kscW®TtkH) k! z"y Listing 3: A printout of the encoded file produced by the program run shown in listing 2. <7"c+l)c0-) ,9=) ;<-; , cppe4)6/4-Aoc>l:/161)ccc. : 7 5" c; -+: -+3. ,=#d,5*7-.<=27 .d.7=;Bd27=8d; . 9>+52 ,d8/d68 5-*?2* eeeeeeeee>9e9 ,> +38 e : 6+8=e9 8e=/-e 1,997 r, 997 le7J==6/s f fff f3TfR°d©tf3LaTYRfbZYOP]Q°Wf JTXPfTYf8ZWOLaTLtf ,Xf©PYOTYRf dZ° f LWW °TU_gbUMgO[a©UQ©gNM°ug4 [®Qg TQgS [ °g°T© [ aSTu hhhhhDR [ ahOf haURh° RP_Rah_R° RNJPUhSNPVYVaf h© [ haURh©ba° PV_a° h©Sh : ©YQNcVNhOVaf O^RiVORi©] ib° J ePZSiPcgW®UibVSiPZcS©°W®baiT] ° ibVSiR SORSRipP] ] [vP] ] [p ®XbbX[TxjCWThjWPSjPjR©] RTbbX©] jbcP] Sj©dcjUa©] cjbT[ [X] VjcWPcjP] Sj©cWTa °©Q^cyk9r f 5>®kRbY^WkdXU] kRQ6[kY^>k] ikR dXUU©yk>UUTKQ^ idXY's>WkU®cU/kscW©TtkH ) k ! z* April 1982 © BYTE Publications Inc 433 Programming Quickies. Listing 4: A run of the encoding-decoding program, this time decoding the file shown in listing 3. ENCODING PROGRAM Password ? THE RAIN IN SPAIN FALLS MAINLY ON THE PLAIN Encoding or Decoding (1 or 2) ? 2 Name of File to be DECODED ? SECRET. X9 Name of file to receive 'doctored 1 output ? FRM.X9 <7 n c+l)cO-) ,9=) ;<-: ; cppc4 ) 6/4-Aoc> 1 : /16 1 ) ccc . : 7 5" c; -+: -+3. ,=#d,5*7-.< = 27 .d.7=,Bd27=8d; . 9>+5 2 , d8/d6 6 5-*?2* SUBJECT. CLANDESTINE ENTRY INTO REPUBLIC OF MOLDAVIA eeeeeeeee>9e9, >+38e: 6+8=e9 8e=/-el,997r,9 971e7 3==6/s TO OBTAIN PLANS ON SECRET 'BOOM-BGGM 1 MISSLE. ff ff f3TfR°d©tf3LaTYRfbZY0P]Q°Wf_TXPfTYf8ZW0LaTLtf , Xf^PYOTYRf dZ ° f LWW Hi guys. Having wonderful time in Moldavia. Am sending you all °TU_gbUMgO[a©UQ©gNM°ug4 [®Qg_TQgS [ °g°T© [aSTu this via courier bat. Hope she got through. hhhhhDR [ ahOf haURh° RP_Rah JR° RN_PUhSNPVYVaf h© [ haURh®ba° PV_a° h® Sh : ^YQNcVNhOVaf Went by the secret research facility on the outscirts of Moldavia City O^RiVORi®] ib°] cPZSiPcgW©UibVSiPZcS©°W®baiT] ° ibVSiR SORSRipP] ] [vP] ] [p and had no trouble buying the blueprints for the dreaded 'boom-boom' ®XbbX[TxjCWThjWPSjPjR©] RTbbX©] jbcP] Sj©dcjUa©] cjbT[ [X] VjcWPcjP] Sj©cWTa missile. They had a concession stand out front selling that and other °®Q©cyk9r®®kRbY©WkdXU]kRQS[kY©k] ikR dXUU©yk>UUTkQ©idXY©WkU®cU/kscW©TtkH) k! z"y plans. I'll bring them back in my bootheel. Need anything else? (sgnd) X9 1/2. try to read into a string variable a DATA statement con- sisting of two words separated by a comma. When both words and the comma read in, you've found the location. Another approach is to use more string variables, creating a new one each time a comma is encountered. Three or four variables would probably suffice, but occa- sionally you'll lose a space that falls at the front of the next string variable. It's better to find that delimiter character. Aside from the way it handles commas, this program is really pretty simple — but the code it generates is not. The encryption begins as a simple offset. The program first reads your password (or passphrase) and sums the ASCII values of all the letters and spaces. To obtain the offset, the program divides the sum by the number of letters and spaces in the password. With an offset of 63, for example, every letter is printed 63 characters higher than it actually is (with a wrap-around feature to maintain the desired ASCII range of 32 to 123 and an upward shift of one so no space will be printed). In each succeeding line, the off- set is increased by one. This prevents anyone from break- ing your code by analyzing frequency of character ap- pearance. Every single letter and space is represented by a different character in every line. For spies, my encoding-decoding program comes in handy almost daily. Listing 2, for example, reveals how I ran the program to encode a message during my last CIA mission behind the Iron Curtain. Listing 3 is the printout of the encoded file I sent to Langley, and listing 4 shows a program run that decoded the same file. Decoding is merely the reverse of the encoding operation, but you must give the password. With this program and a portable computer like the Osborne 1, you too can be a spy. Go forth, my fellow agents, and have secrets from one another! ■ 434 April 1982 © BYTE Publications Inc Software Received Apple Adenoids, a medical ad- venture game for the Apple II. Floppy disk, $29.95. Lym- phatic Software, 12 Sinus Way, Psychosomatic, NH 03458. Amperdump, a high-res- olution graphics dump utility program using the Epson MX-80 or -100 printer for the Apple II Plus. Floppy disk, $30. Madwest Software, POB 9822, Madison, WI 53715. Ampergraph, a graphics utility package to generate plots and graphs for the Apple II. Floppy disk, $30. Madwest Software (see ad- dress above). Antfarm, a language sys- tem for teaching program- ming to children for the Apple II. Floppy disk, $49.95. WIMS Computer Consulting, 6723 East 66th PL, Tulsa, OK 74133. Bug Attack, an arcade- type game for the Apple II. Floppy disk, $29.95. Cavalier Computer, POB 2032, Del Mar, CA 92014. David's Midnight Magic, a high-resolution pinball game for the Apple II. Floppy disk, $34.95. Broderbund Software Inc., 1938 Fourth St., San Rafael, CA 94901. Hi-Res Secrets, a graphics development package for the Apple II. Floppy disks, $125. Avant-Garde Creations, POB 30160, Eugene, OR 97403. High-Res Mastertype,a typing instruction game for the Apple II. Floppy disk, $39.95. Lightning Software, POB 11725, Palo Alto, CA 94306. The Manipulator , a tex t file utility system for the Apple II. Floppy disk, $34.95. Pear Software, 407 Terrace, Ashland, OR 97520. Menu Generator, a menu- development software system for the Apple II Plus. Floppy disks, $39.95. Crane Soft- ware Inc., Suite 611, 16835 Algonquin, Huntington Beach, CA 92649. Nutrichec 2.0, a diet and physical activity analysis program for the Apple II Plus. Floppy disk, $59.95. WIMS Computer Consulting (see address above). Personal Tax Plan, an in- come tax planning package for the Apple II and the Western Digital Microengine. Floppy disk, $130. Aardvark Software Inc., 783 North Water St., Milwaukee, WI 53202. Stone of Sisyphus, an adventure game for the Apple II Plus. Floppy disks, $29 . 95 . Adventure Interna- tional, POB 3435, Long- wood, FL 32750. Ultra Plot, a plotting utility program to create charts and graphs for the Apple II. Floppy disks, $70. Avant- Garde Creations (see address above). Versaform, a business forms processing package in Pascal for the Apple II. Floppy disk, $389. Applied Software Technology, 15985 Greenwood Rd., Monte Sereno, CA 95030. CP/M Ddump 1.6, a sector- oriented disk dump utility program for CP/M. 8-inch floppy disk, $29.95. Elektro- konsult Inc., Konnerudgt. 3, N-3000 Drammen, Norway. Dtest 1.7, a disk- and disk drive-testing program for CP/M. 8-inch floppy disk, $29.95. Elektrokonsult Inc. (see address above). The Formula, a multifunc- tioned, business-oriented data-processing system for CP/M. 8-inch floppy disk, $595. Dynamic Micropro- cessor Associates, 545 Fifth Ave., New York, NY 10017. PET RPL Language, a compiled language system for the PET-2001. Cassette, $71.91; floppy disk $80.91. Samurai Software, POB 2902, Pom- pano Beach, FL 33062. Vigil, an interactive graph- ics and game development system for the VIC-20. Cas- sette, $35. Abacus Software, POB 7211, Grand Rapids, MI 49510. TRS-80 ColorFORTH, a FORTH language system for the TRS-80 Color Computer. Cassette, $49.95. Armadillo Software, POB 7661, Austin, TX 78712. Do-It-Yourself Adventure Kit, an adventure game development program for the TRS-80 Models I and III. Floppy disk, $29.95. Subur- ban Software Co., R.D. #1, Box 74A, Spring Mills, PA 16875. Hexspell 2, an extended spelling checker for the TRS-80 Models I and III. Floppy disk, $99. Hexagon Systems, POB 397, Station A, Vancouver, British Col- umbia V6C 2N2, Canada. Imperial Arena, a Star Trek-type game for the TRS-80 Model I. Cassette or floppy disk, $15. Richard Bissonnette, POB 476, Amherst, MA 01004. Linear Programming Sys- tem, a system to solve linear programming problems for the TRS-80 Model I. Cas- sette, $9.89. Computer Heroes, 1961 Dunn Rd., East Liverpool, OH 43920. Macro-Assembler 4004, an emulation of the 4004 micro- processor for the TRS-80 Models I, II, III, IV, etc. Hard disk, $1.95. MacaroonSoft, 45 The Way of All Flesh, Spittingboro, NH 03458. Newtrieve, an indexing and data-retrieval program for the TRS-80 Models I and III. Floppy disk, $49.95. Unique Printing and Sta- tionery Co., 11 Maiden Ln., New York, NY 10038. Refware Thesaurus: Builder 1.0, a specialized thesaurus development program for the TRS-80 Model III. Floppy disk, $149.95. Refware, POB 451, Chappaqua, NY 10514. Silly Syntax, a story crea- tion game for the TRS-80 Color Computer. Cassette, $19.95. Sugar Software, 2153 Leah Ln., Reynoldsburg, OH 43068. Stone of Sisyphus, an adventure game for the TRS-80 Models I and III. Floppy disks, $29.95. Adven- ture International, POB 3435, Longwood, FL 32750. Other Computers Fifth, a language system for the Atari 400/800. 25 ozs., $7.95. fig-Fork Software Inc., Frodo Alley, Fraternity, NH 03458. Match/Bowl, two arcade- type games for the Bally Arcade. Cassette, $12.95. Edge, 12046 Flambeau Dr., Palos Heights, IL 60463. ■ This is a list of software packages that have been received by BYTE Publications during the past month. The list is correct to the best of our knowledge, but it is not meant to be a full description of the product or the forms in which the product is available. In particular, some packages may be sold for several machines or in both cassette and floppy-disk format; the product listed here is the version received by BYTE Publications. This is an all-inclusive list that makes no comment on the quality or usefulness of the software listed. We regret that we cannot review every software package we receive. Instead, this list is meant to be a monthly acknowledgment of these packages and the companies that sent them. All software received is considered to be on loan to BYTE and is returned to the manufacturer after a set period of time. Companies sending software packages should be sure to include the list price of the packages and (where appro- priate) the alternate forms in which they are available. April 1982 © BYTE Publications Inc 435 Circle 161 on inquiry card. rEL eas e - MICROSTAT™ Release 2.0 Just some of the new features of Microstat Rel. 2.0 in- clude: new programs for moments about the mean, skewness, kurtosis and stepwise multiple regression, longer file names, faster sort routine, the ability to declare each data file's numeric precision and drive location plus an expanded user's manual with new appendi- ces for the equations and file structures used in Microstat. Also included is a Data Management Subsystem for file maintenance (edit, list, destroy, augment, sort, rank-order, move and merge) plus trans- formations (add, subtract, multiply, divide, reciprocal, log, natural log and antilog, exponentiation and linear) that allow you to create new variables from existing variables. After file creation with DMS, programs for analysis include: Descrip- tive statistics, Hypothesis testing (mean and proportion), AN OVA (one-way, two-way, and random blocks), Scatterplots, Frequency distributions, Correlation analysis, Simple, Multiple and Stepwise Multiple Regression (including files larger than available memory), Time series, 1 1 Nonparametric tests, 8 Probability distributions, Crosstabs and Cht-square, Combinations, Permutations and Factor- ials (up to one million factorial). All program output is neatly formatted for easy use. The price for Microstat Rel. 2.0 is $295.00 and the user's manual is available for $25.00 (credited towards purchase) and includes sample printouts with file tables that reference standard statistical texts and journals so you can compare the results from Microstat to those produced on much larger systems. Compare Microstat to any other package on the market and we think you'll agree that Microstat is the best at any price. ECOSOFT, INC. P.O. BOX 68602 INDIANAPOLIS, IN 46268-0602 (317) 283-8883 Wordstar* Magic Wand CP/M Compatibility for your TRS-80 Pluggable boards & powerful operating system (T8/0S) run this power packed lineup of CP/M program applications on your Mai! Merge* Mailman* Spell star* Supersort* Word Processing Mail Management Special Applications Data Base Management dBase II* Quic-N-Easi* Tim III* Calc Star* Super Calc* Business Applications The Boss The Freedom Family Freedom Option $275.00 CP/M Compatibility Freedom Plus $490.00 CP/M Compatibility Plus 64K RAM Manual Only $25.00 Freedom Technology International, Inc. Helping Small Computers Do Big Things To Order call 1-800-523-4067 In Pennsylvania call 569-2381 Dealer Inquiries Invited *CP/M is a trademark of Digital Research, Inc. TRS-80 is a trademark of Tandy Corp. Programming Quickies Base Conversion on the TRS-80 Pocket Computer David M. Dolan POB 632 South Pasadena, CA 91030 Base conversion, indispensable to the programmer, has been a favorite subject for programs since the earliest issues of microcomputer magazines. But because the need for converting numbers from one base to another usually arises while the computer is tied up developing a pro- gram, it is impractical to load and use a base-conversion program at the same time. Until Tandy began selling its TRS-80 Pocket Computer, the only other choice was the Texas Instruments Programmer calculator. Base conversion at first appeared to be a natural for the Pocket Computer (PC). A second glance, however, revealed some obstacles. PC BASIC lacks two functions used extensively in previous base-conversion programs: string-manipulation and the ASC function, which returns the ASCII (American Standard Code for Information In- terchange) code for string argument. Could I make a limited BASIC perform like an extended BASIC? It was a challenge I couldn't resist. The program that met the challenge is shown in listing 1. It will convert any binary, octal, decimal, or hexa- decimal number (up to decimal 65535) to its binary, oc- tal, decimal, or hexadecimal equivalent. This represents an improvement over the TI Programmer calculator, which can't handle binary numbers. The only concession I had to make to the limitations of PC BASIC is this: each digit of a number must be entered separately and followed by Enter. You designate the end of a number by entering a space (SPC), followed by Enter. The program then asks for the base of the number to be converted; you enter 2, 8, 10, or 16. In the same way, the program asks the base to which the number is to be converted. That's all there is to it. Unfortunately, the Pocket Computer doesn't perform conversions as fast as a larger microcomputer or the TI Programmer. This PC BASIC program takes 15 seconds to change decimal 255 to hexadecimal FF, and 45 seconds to change binary 11111111 11111111 to hexadecimal FFFF. I tried various ways to make the program run faster. Some of them saved memory, but all ran slower. Perhaps you can do better. Beware of trying to translate this program into other 436 April 1982 © BYTE Publications Inc Circle 181 on inquiry card. dialects of BASIC. The program takes advantage of some of PC BASIC'S peculiarities. Line 500, for instance, makes use of the fact that the string A$ is the same as A$(l), B$ is the same as A$(2), etc. The sample run of the program is shown in listing 2 on page 438. To produce the printout, I translated the pro- gram to run on the TRS-80 Model II. The printout is similar to what you will find on the Pocket Computer. I produced the program listing itself (listing 1) by copying the debugged program by hand directly from the Pocket. Computer to a Radio Shack Model II. Although not as reliable as a listing from a running program, this listing was the best one possible at the time. (Since then, Tandy has released a printer for the Pocket Computer.) If, like me, you're a gadgeteer as well as a computer nut, you may have been looking for an excuse to buy one of the new pocket computers. This base-conversion pro- gram may give you that excuse. Depending on your needs, the base-conversion program might justify more than half the price of the new gadget. ■ Listing 1: A program for converting numbers from one base to another. Designed to run on the TRS-80 Pocket Computer, the pro- gram can convert a binary, octal, decimal, or hexadecimal number to its equivalent in the other three bases. 10 20 30 *b 50 60 70 80 90 100 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 27 280 290 300 310 320 350 360 370 380 400 410 420 430 500 PAUSE PAUSE CLEAR IFA$( NEXTU INPUT INPUT VsOtW FORTs IFA( VrV+ NEXT IIQIt ii i it ii 2 ii it o it ii 4 ii II C 11 II g M n n II llgli " 9 ii "A" ii 5 ii "C" »D" II CM lip II A$(2 A$(3 A$(3 IFRs IFR = IFRs IFRs Y=V: FORT A$(U NEXT PR IN "BASE CONVERSION" "ENTER DIGITS SEPARATELY" : PAUSE"PPESS ENTER AFTER EACH" :FORUs26TC41 :INPUT"DIGIT (SPC TO EXIT) : " ; A$( U) U)=" "LETUsU-1 :GOT060 #(2,8,10,16): TC( 2,8, 10,16) "BASE CF "CONVERT = UT026STEP-1 :G0SUBA$(T) T)>QBEEP1 : PAUSE" INVALID INT(A(T)*Q~W+.5) :WsW+l T:GOT0300 A(T)s0: RETURN A(T)s1 : RETURN A(T) =2: RETURN A(T)=3:RETURN A(T)=4:RETURM A(T)=5:RETURN A(T) =6: RETURN A(T)=7:RETURN A(T)=8:RETURN A(T) =9: RETURN ACT) si 0«: RETURN A(T)s1 1 : RETURN ;Q INPUT" :GOT03 A(T)s12 A(T)s13 A(T)=14 A(T)s15 6)="0": : RETURN : RETURN : RETURN : RETURN A$(27)s' 1 A$(28)="2" A$(34)="8" 7)="B":A$(3 8)="C":A$(39)="D" it -j ii 2)="6":A$(33)="7" A$(29) AS (35) ="9" A$(40)="E" A$ ( 3 ) = " 4 " : AS ( 3 1 ) = " 5 »' :A$(36)r»A" :A$(41 ) ="F" 16GOSUB400:SS="HEX: 10GOSUE400:S$="DEC: 8GOSUB400:S$s»OCTAL: 2GOSUB4 00:S$s"BINARY: w :GOSUB500 :GOSUB500:GOTO30 :GOSUB500:GOT030 GOT030 GOTO 30 :GOSUB500 WsINT(L0GV/ LOG R+. 000001 ) :U=1 sWTC0STEP-1 :X=INT( R*tf+.5) :Q=INT(Y/X) )sA$(Q+26) :U=U+1 : Y= INT( Y-Q*X+ .5 ) T: RETURN TS$ ; " " ; A$ ; B$ ; C$ ; D$ ; E$ ; F$ ; G$ ; H$ ; 1$ ; J $ ;K$ 1$;M$;0$;P$: RETURN April 1982 © BYTE Publications Inc 437 Programming Quickies. Listing 2: A sample run of the base-conversion vrosram in listino 7 W„*« tkJ,* „u . • , ,. Press Enter. The user marks a dig it as the numUZby ^ ^££Z3Z%£ ^ " " ^ *? ^ ^ Ready >RUN BASF. CONVERSION ENTER DIGIT DIGIT DIGIT DIGIT DIGIT BASE OF CONVERT DIGITS SEPARATELY (SPC TC EXIT) :? F EXIT) :? C EXIT) :? 7 EXIT) :? E EXIT) if (SPC (SPC (SPC (SPC # (2,8,10,16) TO(2,8,10,16) TO TO TC TO BINARY 1111110001111110 ENTER DIGITS SEPARATELY DIGIT (SPC TC EXIT) :? 3 DIGIT (SPC TO EXIT) :? 2 DIGIT (SPC TO EXIT) :? 7 16 2 DIGIT (SPC TO EXIT):? DIGIT (SPC TO EXIT) :? DIGIT (SPC TC EXIT) :? BASE OF // (2,8,10,16) : CONVERT T0(2,8,10,16): HEX 7FD5 2 5 o 9 ENTER DIGIT DIGIT DIGIT DIGIT BASE CONVERT HEX EF DIGITS SEPARATELY (SPC TO EXIT) :? 3 (SPC TC EXIT) :? 5 (SPC TO EXIT) :? 7 (SPC TO EXIT) :? OF # (2,8,10,16):? T0(2,8,10,16) ENTER DIGITS SEPARATELY DIGIT (SPC TO EXIT) :? 10 16 8 16 ■ liiiifi Promptly for Much Less Than Most Retail Stores •SPECIAL! BUY 10 and GET ONE FREE! OFF!! f OR MORE f YOUR PRINTER ANADEX 9000 Series CENTRONICS 700-703,737,779 CENTRONICS 100, 101A. 102. 103,300,301,306,308,330, 358.398,500,501,503,508, 588, 620, 820 CENTRONICS 704-705 DEC W x 4QYD DEC Vi x 60YD. DIABLO HYTYPE II (M/S BLK) HI YIELD. FITS 70 PRINTERS! EPSON MX70.80 IBM - SILVER DOLLAR" Sys. 34, Sys. 32 MDLA, Series IMDL4974, 5256, 3287, 3770, 3771-3774,4974,5100,5103, 5110,5228,5256,5320MDLA IBM - HARMONICA W. SERIES I. MOD 4973/11, 3200, 3289, MOD 2 NEC SPINWRITER OUME (FITS 80 PRINTER MODS) RADIO SHACK DAISY WHEEL I! RADIO SHACK LPIII, LPV RADIO SHACK LPII. LPIV TELETYPE MOD 33, 28, 35, 37, 38, 88 WANG M/S. 5541W, WC, 5581, WD, 6581W, 2281W PACK SIZE 1 pk 3/pk 3,'pk T/pfc 3/pk 3,'pk 1/pk 1 pk. 5/pk 3/pk 4/pk 3/pk 1 pk one, pk 3 pk 10/ pk 1/pk RETAIL LIST" 1400 ea 18 95/3 pk 26.33/3 pk 16.95 ea 17 77/3 pk 20.12/3 pk 9.31 ea 16.00 ea 5 80 ea 9.42 ea 23.40/3 cart 18.00/3 pk 24 95,3pk 13.95/cart 18.95/3 pk 2.40 ea 6.85 ea YOUR WHOLESALE PRICE 14.00 1 1.95/3 pk 17.55/3 pk 13. 9 5/ Giant Cart 12.95/3 pk 14.25/3 pk 6.87 ea IB.OOea 14,90/5 pk 20.85/3 pk 23.60/4 pk ib reload 13.95/3 pk 8.25 8. 95/ Reload rib" only 11.95/3 pk 13 90/10 pk 5.95 ea (14 00 ea) (3. 98 ea) (5.85 ea) (13.95 ea) (4.32 ea) (4. 75 ea) (6.87 ea) (13 95 eal (2 98 ea) (6. 95 e a) (5.90 eai (4.65 ea) (8 25 ea) (8. 95 ea) (3. 98 ea) (1.39 ea) (5.95 ea) 500 5b3" i 45' 5'16"x210' IT'* 120' 1 2"x 180' 5,16" x High Yield 500"x60' 9 16" x 30' COMMENTS I 2" 1'2" x 51' 1 4"x310 250" 500" 563" 12" 5,16"x393' Nylon Jet Blk Nylon Jet Blk Nylon Jet Blk 5 mil Htgh Speed Giant Cart Double Spools Double Spools 300,000 plus imp. Nylon Jet Blk Nylon Jet 81k Nylon Jet Blk Nylon/Ex Lng Life Multistrtke Film Mylar Multistrike Nylon I net Instr Nylon Jet Blk Nyfon Jet Blk Multistrike Film CAT ORDER* C 777 C-7Q0 C-100 C-7045 R-600 R-644 0-511 C-522 R-300 C-350 R-400 C-525 C-789 R-T3 C-700 R-450 C-550 TERMS: MINIMUM PURCHASE - $20 PAYMENT BY: C.O.D.(UPS), CHECK, MASTER CARD, OR VISA CHARGE CARD. VOLUME DISCOUNTS: 20-50 PACKS 10% 51-100 PACKS 15% *UNDER $20, ADD $5 HANDLING. **APPROX. RETAIL. PRICE VARIES. . ANCIE LABORATORIES 5200- J Philadelphia Way 301-345-6000 (Wash. D C Local) Lanham, Maryland 20706 301-792-2060 (Balto. MD Local) 800-638-0987 (National) ADDRESS- CITY _ STATE. ANCIE Laboratories 5200-J Philadelphia Way Lanham. Maryland 20706 301-345-6000 (Wash. DC. Local) 301-792-2060 (Balto. MD Local) 800-638-0987 (National) CAT.# TOTAL 438 April 1982 © BYTE Publications Inc □ Check Enclosed □ C.O.D. □ VISA □ MASTER CHARGE ACCT. # EXP. DATE MIN. ORDER $20 PRICES SUBJECT TO CHANGE Circle 28 on inquiry card. I Career Opportunities in Computing Jacqueline Johnston 1808 Pomona Dr. Las Cruces, NM 88001 Rare is the computer hobbyist who has not considered entering the com- puter field professionally. Just enter- taining the thought, however, raises several questions that are difficult to answer. Is there a demand for com- puter programmers? Is hobby experi- ence of any value in landing a job? The answer to both questions is "yes." Hobby-level interest in com- puters can lead to a rewarding and stimulating career as a computer pro- fessional. There is an urgent need for qualified programmers and analysts in all sectors of commerce and in- dustry. Granted, there are differences be- tween home computing and the world of business and industry, but these differences should not deter you from seeking a career in a field you enjoy. In this article we will examine what the computer programmer does in the "real world," what the requirements are in terms of education and experi- ence, where jobs can be found, and what to expect for the general pay About the Author Jacqueline Johnston, a former guidance counselor, is now a computer programmer with the Business Data Systems Office, White Sands Missile Range. The opinions expressed here are her own and not necessarily those of the White Sands Missile Range or the U.S. Government. scale. The emphasis will be on pro- grammers, but the information is also applicable to related jobs. Computer programming is a dynamic career field, and a semi- annual survey of 500 companies by Fortune magazine shows that pro- gramming is virtually recession- proof. The demand for programmers is expected to increase more rapidly than the average demand in other fields, and the trend will continue through the mid-1980s as computer usage expands in business and re- search. Newspapers and magazines are filled with advertisements for pro- grammers and analysts. In my job as a guidance counselor, I receive count- less inquiries from companies search- ing for computer programmers. Programming is an attractive field from the standpoint of both salary and working conditions. College placement offices report that com- puter-oriented graduates receive salary offers of approximately $1691 per month. In a recent poll I con- ducted of 150 companies hiring pro- grammers, the average entry-level salary was $1665 per month. Experi- enced programmers can expect higher salaries, ranging up to $50,000 a year. How to Choose Programmer — mathematician — computer scientist — engineer. They all sound interesting, but which one is for you? Let s take a look at the work that each entails. An engineer should have a bachelor's degree (often a master's is required) in one or more of the engi- neering fields: civil, electrical, me- chanical, etc. Engineering positions generally involve design work — de- signing roads, machinery, buildings, or computers. These positions require a solid background in mathematics and some familiarity with computers and programming, as many solutions to engineering problems are arrived at through the use of preexisting or "canned" computer programs. If you are interested in design, an engineer- ing career might be the thing for you. If you prefer programming and hands-on computer work, another field might be more to your liking. The position of computer scientist evolved about ten years ago, so it is relatively new. A bachelor's degree in computer science is needed, and some positions require a master's degree. The educational background is broad in scope, and it includes the study of mathematics, computer hardware, computer operations, systems pro- gramming, compiler and assembler design, and high-level languages. Consequently, computer scientists April 1982 © BYTE Publications Inc 439 Therms no business like dough business. The business of making money. It's all very exciting. But w ithout the ability 7 to lay out a large amount of cash, you can t take advantage of the financial opportunities that come your way. And venturing all your money without savings in reserve can be dangerous. Because savings are the base of any financial plan. One of the surest, easiest w ays to save some dough is joining the Payroll Savings Plan and buying United States Bonds. \bull never miss the little taken out of each paycheck. Meanwhile, the Bonds grow up to play a part in your future. Of course, with Bonds you're sure of the ending. But then, there's nothing wrong w ith a happy ending. m Gxm A public service of this publication and The Advertising Council. AciJKC * ^s^p . stock%s*r in^merica. POCKET COMPUTER PRIMER ^^ Twenty-five unique programs utilize the pocket computer to open an excit- ing and cost-effective new world of educational computing. Contents in- clude simulations and experiments in ecology, computer logic, navigation, weather, geography, physics, math, finance, language, memory skills, random motion, and a classroom management data base. $9.95 , shipping included SCIENCE & ENGINEERING oUUKLCDUUK byCassLewart Twenty-five professional programs for the pocket computer. 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B3 New York, NY 10023, 212-877-8539 tend to have broad responsibilities in software design and computer-center management. Mathematicians should have a minimum of a bachelor's degree in mathematics, and usually a minor or a second degree in physics or engi- neering. These positions involve the development of mathematical solu- tions to complex problems and the translation of the solutions into effi- cient computer programs. The work provides an excellent mix of mathe- matical and programming duties. Computer programmer positions do not usually require a college degree, but applicable experience is required (and a degree in math, ac- counting, business administration, computer science, physics, or engi- neering is a definite asset). Computer programmers do a lot of what they like best — write programs. This may include systems and applications pro- grams. On projects that require analytical solutions involving higher mathematics or engineering prin- ciples, an engineer or mathematician will usually perform that part of the job and then turn the project over to the programmer for completion. Programming Jobs Broadly speaking, programming can be divided into two principal areas: systems programming and ap- plications programming. Although there is considerable crossover be- tween the two, systems programming involves logical operations, while ap- plications programming involves mathematical and process control operations. Systems programmers frequently employ complex logical operations and concepts to develop executive control programs, monitors, assem- blers, compilers, device utilities, and so forth. Most of their work is done in assembly or machine language and seldom requires the use of mathe- matics beyond algebra. Notable ex- ceptions are certain system-design processes that require a knowledge of statistics. Applications programming is a diverse field that can be broken into three broad subfields: scientific, busi- 440 April 1982 © BYTE Publications Inc Circle 483 on inquiry card. ness, and process control. There are many types of jobs within each of the subdivisions; consequently, we will speak only in general terms. Appli- cations programmers must have a strong background in mathematics. Especially important to scientific pro- grammers are algebra, trigonometry, and calculus. The mathematics of finance is essential to business pro- grammers. Scientific programmers work on problems in all sectors of science and industry, from spaceflight planning to computer design, and from bridge building to chemical analysis. Most scientific programs are written in high-level languages, with FOR- TRAN and PL/ 1 being the most com- mon. Business programmers work on financial applications, but there are many other projects such as inven- tory control and network analysis that fall within the business realm. Business programs are written in high-level languages, such as COBOL, RPG, and FORTRAN. Process control refers to the use of a computer to monitor data from and transmit commands to external equipment in real time. Applications programmers in this area generally have some familiarity with the hard- ware of both the computer and the external equipment. Programs for these functions are usually written in assembly language or a high-level language such as FORTRAN, or a combination of the two. Geographic Distribution Who has job openings for pro- grammers? Manufacturers, banks, chemical companies, department stores, research firms, fast-food chains, petroleum companies, gov- ernment agencies, and any scientific or commercial activity you can think of. Where are the jobs located? Everywhere. Figure 1 is a computer-generated map that shows the locations of cities where job openings for programmers existed during a recent one-week survey period. (This, incidentally, is just one of several uses for the micro- computer in counseling job seekers.) A plus sign is drawn at the location of y s£z **&: o> o£> Figure 1: The plus signs on this map indicate locations of cities where programmer jobs were advertised during a recent one-week survey period. About 210 cities, representing more than 1100 programmer job openings, are illustrated. every city where there were one or more programmer jobs during the survey period. Since only one plus sign is drawn for any city, regardless of the number of jobs available, there are many more jobs than plus signs. This par- ticular map illustrates jobs in about 210 cities; the total number of jobs was more than 1100. The majority of jobs are concentrated in and around certain large population centers, as is readily apparent on the map. Note especially the concentration of plus signs near San Francisco, Los Angeles, Phoenix, Denver, Dallas, Houston, Chicago, New York City, Washington DC, and Miami. Requirements So computer programming sounds like an attractive career field? What are the requirements for entry? Most companies prefer that applicants have a bachelor's degree. Scientific and en- gineering organizations prefer degrees in computer science, mathematics, engineering, or the physical sciences. Organizations with business applica- tions prefer applicants with course- work in computer science, account- ing, and business administration. Of course, some workers with applicable experience in programming may be able to secure a position without a college degree. Good verbal and written-communications skills are always an asset. Normally companies prefer basic familiarity with one or more computer languages. To keep track of the programming languages that are in demand, I per- form a weekly survey of the lan- guages required to qualify for jobs advertised during each survey week. In order to make the data available to my clients in a meaningful form, I use a microcomputer to generate a bar chart of the survey results. The chart created for a recent typical period is illustrated in figure 2. Survey figures are entered by means of the keyboard of a video terminal and the chart itself is printed on a line printer. For the sake of simplicity, the program is written in BASIC (see listing 1). It is brief and straightforward. The only change you might need to make is in the syntax of the PRINT #2 state- ments that send output to the line printer. (Not all versions of BASIC use this syntax.) Returning to the bar chart, it's strikingly clear that during the par- ticular survey period illustrated, knowledge of COBOL was required for more jobs than any other lan- guage, followed by FORTRAN, April 1982 © BYTE Publications Inc 441 LANGUAGES REQUIRED FOR JOB OPENINGS ADVERTISED DURING WEEK OF 11 MAY 81 ALGOL ** 1.9 7. APL * ,9 7. BASIC **** 3.8 7. COBOL **********************^^ 67.9 7. FORTRAN ************************* 25.2 X PASCAL ******* 6.7 7. PL/1 ************** 13.5 % RPG ******************* 19.4 7. ALL. OTHERS *************** 14.5 7. ASSEMBLERS ************************************* 36.8 % 10 f f + + + + + f + + + + _„ 30 40 50 60 70 80 PERCENTAGE OF JOB OPENINGS REQUIRING EACH LANGUAGE - + — 90 -4 100 Figure 2: Bar chart showing which programming languages are required to qualify for jobs advertised. Totals exceed 100 percent because many jobs require knowledge of more than one language. Listing 1: BASIC listing of the bar-chart program, which is useful for anyone who wants to keep tabs on programming-language requirements for jobs. 1000 1020 1040 1060 1080 1090 1100 1200 1300 1340 1350 1360 1400 1500 1600 1700 1800 1900 1920 1940 1950 1960 1970 2000 2100 2200 2300 2400 2500 2600 2640 2650 2660 2670 2700 2800 2900 3000 3100 3200 3400 3500 3600 3700 3800 REM REM REM REM REM DIM L$ DATA " DATA " DATA REM REM REM OPEN FOR 1 = PRINT NEXT I PRINT INPUT REM REM REM REM REM FOR 1= READ L PRINT INPUT NEXT I PRINT INPUT REM REM REM REM PRINT PRINT PRINT PRINT PRINT FOR 1 = IF IO PRINT PRINT PRINT- PRINT THIS PROGRAM GENERATES A BAR CHART ILLUSTRATING THE PERCENTAGE OF JOB OPENINGS REQUIRING KNOWLEDGE OF EACH OF THE VARIOUS PROGRAMMING LANGUAGES. THE CHART IS BASED ON STATISTICAL DATA SOLICITED FROM THE USER. BASIC f ' PL/l a T ' ( 10 > w H < 1 ) ALGOL" t* APL"f" FORTRAN" t* PASCAL*," ALL. OTHERS " r " ASSEMBLERS " FILE *2 IS THE LINE PRINTER. L. P J " F R U T P U T A S F I L 15, # 2 1 TO 10 "SURVEY CONDUCTED FOR WEEK BEGINNING WHEN?" W$ COBOL" RPG" FOR EACH OF THE TEN LANGUAGES ? READ THE LANGUAGE NAME FROM THE DATA STATEMENTS AND REQUEST THE NUMBER OF JOBS REQUIRING THAT LANGUAGE. 1 TO 10 ■NUMBER OF JOBS REQUIRING NCI) ' ?L* 4200 PRINT #2: 4240 REM 4250 REM PRINT OUT THE LANGUAGE NAME* 4260 REM 4300 print #2:l$(d; " "I 4400 IF J=0 THEN 4800 4430 REM 4440 REM PRINT OUT A ROW OF ASTERISKS r THE NUMBER OF WHICH CORRESPONDS 4450 REM TO THE PERCENTAGE OF JOBS REQUIRING THE LANGUAGE. 4460 REM 4500 FOR K*l TO J 4600 PRINT #2 *-"*'"» 4 700 NEXT K 4740 REM 4750 REM PRINT OUT THE PERCENTAGE AT THE END OF THE LINE OF ASTERISKS, 4760 REM 4800 PRINT *2lPt 4 %" 4900 NEXT I 5000 PRINT #21 5020 PRINT #2: 5040 REM 5050 REM 5060 REM 5070 REM 5110 PRINT #2iTAB(ll) % "+' ? 5120 FOR 1*1 TO 20 5130 PRINT #21 "-- - + ' r 5140 NEXT I 5150 PRINT #2i 5300 FOR 1*0 TO 100 STEP 10 5400 PRINT #2 : TAB (1+ 10) llf 5500 NEXT I 5600 PRINT #2 J 5700 PRINT #2:TAB(37) J 'PERCENTAGE OF 5800 FOR 1*1 TO 10 5900 PRINT *2: 6000 NEXT 1 6100 STOP 6200 END THE STATEMENTS FROM HERE THROUGH LINE 5500 PRINT OUT A NUMERICAL SCALE AT THE BOTTOM OF THE CHART* JOB OPENINGS REQUIRING EACH LANGUAGE" exist, especially in Washington DC. Government employment is attrac- tive from several standpoints and it offers good benefits in the areas of leave and retirement. Persons doing computer program- ming work are usually hired as math- ematicians, computer programmers, or computer scientists. Entry -level salaries for these positions range from $12,266 to $15,193 per year. There are also various trainee posi- tions, a number of which are filled through PACE (Professional and Ad- ministrative Career Examination), a written test. Veterans who served be- tween August 5, 1964, and May 7, 1975, may be eligible for a VRA (Veterans Readjustment Appoint- ment). These positions offer training programs, and the veteran need not participate in regular competitive procedures, although he or she must meet the position's minimum require- ments. For more information on jobs with the federal government, contact your local Federal Job Information Center, or call (800) 555-1212 to request a toll-free number. Going to School If you are interested in attending college to study computer program- ming, there are several publications that will help you locate schools of- fering suitable programs. Some of the most useful books are: Lovejoy's Col- lege Guide, Chronicle Guide to Four- Year College Majors, and The Col- lege Blue Book (four volumes). These are available at most public libraries, and they list colleges with programs in computer science and mathe- matics, offer brief descriptions of the colleges, and list tuition, admission requirements, etc. College credits may also be earned through work experience and inde- pendent study. Credits for this Circle 163 on inquiry card. BOOKS and SOFTWARE For ATARI - PET - OSI - APPLE II - 8502 ATARI BASIC - Learning by Using This new book is an "Action"- Book. You do more than read it. Learn the intricacy of ATARI- BASIC thorugh the short programs which are provided. The suggestions challenge you to change and write program routines. Yes, it's exciting - Many of the programs are appropriate tor beginners as well as experienced computer users. (Screen Drawings, Special Sounds, Keys, Paddles + Joysticks. Specialized Screen Routines, Graphics and Sound. Peeks and Pokes and special stuff ). Order-No. 164 S9.95 Games for the ATARI Computer How to program your own games on the ATARI. Complete listings in BASIC and Machine Language of exciting games. Tricks and hints. Order No 162 £4.95 ATMONA-1 Machine Language Monitor for the ATARI 400/800. This powerful monitor provides you with the firmware support that you need to get the most out of your powerful system, ATMONA-1 comes on a bootable cassette. No cartridges required. Disassemble, Memory Dump HEX + ASCII. (Change Memory Locations, Blocktransfer, fill memory block, save and load machine language programs, stBrt mach. Lang. Progr. (Printer optional). Comes with introductionary article on how to program the ATARI computer in machine language. (Available also in ROM) Order No. 7022 619.95 ATMON A-2 Superstepper A very powerful Tracer to explore the ATARI ROM/RAM area. Stop at previously selected address. Opcode or operand (cassette). Order No. 7049 649.96 EDITOR/ ASSEMBLER for ATARI 800, 32K RAM Extremely fast and powerful Editor/Assembler (8K Source code in about 5 seconds) Includes ATMONA 1 Order No. 7098 649.95 MACRO Aitembler for ATARI 800, 48K RAM Please specify your system; RAM, disc or cassette. Order-No. 7099 689.00 Gunfight - For ATARI 400/800 16K RAM, needs two joysticks, animation and sound. (8K machine language) Order-No. 7207 619,95 EPROM BURNER for ATARI 400/800. Bare boards only with description, schematic + software (2716,2732). Order-No, 7041 699.00 Invoice Writing for very small business with ATARI 400/800 16K RAM. Order-No. 7022, can. 629.65 Order-No. 7200, ditc. 639.99 Word processor for ATARI 800, 48K RAM Order-No 7210 629.95 How to connect your EPSON- Pr inter to the ATARI 400/800. Construction article with printed circuit board and software. (Screenprlnt and variable charac- ters per line). Order No. 7210 819.95 OSI OSI Bo^kTWrl^eTi OSI The First Book of Ohio Scientific Introduction to OSI computers. Diagrams, hardware and software information not previously available in one compact source. 192 pages. Order No 157 87.96 The Second Book of Ohio Scientific Very valuable information about OSI microcomputer systems. Introduction to OS-65 D and OS-65U networking. Hardware and software hints and tips. Systems specifications. Business applications. Order No. 158 67.95 The Third Book of Ohio Scientific is now available! Very important information for the OSI system experimenter. Interface techniques, system ex- pansions, accessories and much more (EPROM-Burner, 6522 1/0- card with IK RAM, Soundboard. EPROM/RAM board). Order-No. 159 87.95 The Fourth Book of OHIO V IP-Book - Very Important Programs. Many interesting pro- grams for OSI computers. Sorting (Binary Tree). Differential Equi- tation, Statistics, Astrology, Gas Consumption, Games a. s. o. Order No. 160 89.95 VIP Package - Above book plus a cassette with the programs. Order-No. 160 A 819.95 The Fifth book of Ohio Scientific Many exciting programs program- ming hints and tricks, Textwriter, Debugger for CI P, Games, Utilities and much more (polled keyboard) Order-No. 161 87.95 Invoice Writing Program for OSI - C1PMF, C4P. Disk and Cassette, 8K RAM. Order-No. 8234 829.80 Mailing Lilt for C1PMF or C4PMF 24K RAM 250 addresses Incf. phone number and parameters on one 5 1 1 A disk) Order- No. 8240 829.80 8K Microsoft BASIC Reference Authoritative reference for the original Microsoft 4K + 8K BASIC developed forALTAIR and later computers including OSI,PET.TRS-80and VIC. Order-No. 141 89.95 Ex pa niton Handbook for 6502 and 6802 S 44 Card Manual describes all of the 4.5 x 6.5 44-pin S-44 cards incl. schematics. A MUST for every 6502 system user {KIM. SYM, AIM, VIC. PET, OSI) Order No. 152 69.95 Microcomputer Application Notes Reprint of Intel's most important application notes including 2708. 8085, 8255, 6251 chips. Very necessary for the hardware buff. Order No. 153 89.95 Complex Sound New revised applications manual for the Texas Instruments SN 76477 Complex Sound Genera- tor. Order No. 154 86,95 Smell Business Program* Complete listings for the business user. Inventory, Invoice Writing, Mailing List and much more. Introduction to Business Appli- cations. Order No. 156 814.90 Microcomputer Hardware Hand- book Descritions. pinouts and specifi- cations of the most popular microprocessor and support chips. A MUST for the hardware buff. Order No. 29 814.96 Care and Feeding of the Commodore PET Eight chapters exploring PET hardware. Includes repair and interfacing information. Pro- gramming tricks and schematics. Order- No. 150 69.95 Prototype-Expansion Board for VIC-20 IS-44 Bui). Order No. 4844 618.95 16K RAM/ROM board for S44- bus. Any combination of RAM and ROM on one board. (SY2128or2716) Order-NO. 613 639.95 Low cost expaniton boards for your APPLE II. Bare board comes with extensive description and software. Prototyping card Order- No. 604 829.00 6522 VI A- I/O Exp. Order No. 605 839.00 2716 EPROM-Bumer Order-No. 607 849,00 8K EPROM/RAM Card Order No. 606 829.00 ELCOMP Publishing, Inc., 53 Bedrock Lane Pomona, CA 91766, Phone: (71 4} 623-8314 Payment: Check, Money Order, VISA, Mastercharge, Eurocheck. POSTPAID or PREPAID in USA. 8 5.00 handling fee for C.O.D. All orders outside USA: Add 15 % shipping. CA add 6.5 % sales tax. ATARI is a registered trademark of ATARI Inc. APPLE II is a registered trademark of APPLE Inc. April 1982 © BYTE Publications Inc 443 Circle 123 on inquiry card. FEATURES: Menu driven zip code data base. You simply type in the street address, or P.O. box. Instantly, you have the zip code needed. CP/M, APPLE compatible. For more information, call or write to COMPUTORIAL, INC. 4520 Wilshire Blvd. Los Angeles, CA 90010 • (213) 933-8268 Carbonless checks, invoices and statements ^ Standard formats... plus Custom Design Service! ^ Small quantities (as low as 500)... plus money-saving prices! lir Super-fast service (shipped 5 days after receipt of order!) SEND COUPON. ..OR CALL TOLL-FREE: 1-800-328-9697. To: Delmart Company, Division of Deluxe Check Printers, Inc., 530 N. Wheeler St., P.O. Box 43495, St. Paul, MN 55164-0495 please send free color catalog! knowledge can be awarded through CLEP (College-Level Examination Program) and the ACT (American College Testing) Proficiency Ex- amination Program. For information on costs and registration procedures, write to CLEP and ACT for their pamphlets (see the text box 'Tree In- formation/' on page 446). Those eligible for veterans' benefits can receive monthly payments from the VA (Veterans Administration) while attending school. A full-time student with no dependents receives $342 per month, tax free, for forty- five months ($15,390 total). In- dividuals with dependents receive correspondingly larger payments. A veteran with two dependents, for ex- ample, receives a total of $20,880. For more information on VA benefits, contact the VA Regional Office closest to you or the veterans' repre- sentative at the college you wish to attend, or call (800) 555-1212 to ob- tain a toll-free number. Remember, eligibility for veterans' benefits ter- minates ten years after separation from the service or on December 31, 1989, whichever comes first. Getting the Job If you are qualified for entry into the computer programming field, there are several steps that must be taken to secure a position. First, you must prepare an effective resume. Generally, an applicant can prepare a resume without paying a commercial resume writer. If you write it your- self, you will be better prepared to discuss your qualifications during the interview. The resume should be short — never more than two pages, and preferably not more than one. Most resumes are read in ten to fif- teen seconds, so the information should be clear and easy to read. The purpose of the resume is to obtain an interview for the applicant. The ap- plicant will usually have to fill out an application form if the firm is in- terested. When the resume is sent out, a cover letter should accompany it. The letter should be typed, never photo- copied or mimeographed, and per- sonalized to the firm receiving it. Ad- dresses of firms hiring computer pro- 444 April 1982 © BYTE Publications Inc Circle 142 on inquiry card. Circle 69 on inquiry card. grammers can be obtained from The College Placement Annual, Ad Search (a weekly newspaper with em- ployment ads from all over the coun- try), Career Opportunity Update, local newspapers, and industry pub- lications such as ComputerWorld, Datamation, Electronics, and Elec- tronic News. A new publication, Peterson's Annual Guide to Careers and Employment for Engineers, Com- puter Scientists, and Physical Scien- tists, lists companies seeking graduates in these fields. (It is available for $13.25, postage paid, from Peterson's Guides Book Order Dept., POB 978, Edison, NJ 08817.) Free employment counseling and placement services are available at state Job Service offices. There are more than 2400 local offices of the federal-state employment-service system, staffed with professionals who can help with career planning and finding a job. The Employment Service operates a computerized Job Bank system in virtually every state. These Job Banks comprise the largest, most comprehensive and up-to-date source of job openings in the nation. The listings are available on micro- fiche at your local state-employment service office. A number of private employment agencies specialize in finding jobs for individuals with technical skills, and bill the client companies, rather than the job seeker, for their services. Al- though most of these firms are reputable, you should be cautious and read all the fine print before sign- ing a contract. One of the final steps in the job- hunting process is the job interview. There are many publications and books that offer advice on how to prepare for an efffective interview. Its important to learn as much as possible about the company before the interview, to make a presentable appearance, and to speak with con- fidence and enthusiasm. It is a fact of life that choice jobs do not always go to the best-qualified applicant, but to the person who has the best job-hunting skills. The im- portance of resume preparation and interview technique cannot be over- emphasized. MULTIPROGRAMMER avail PS& SYSTEM-10 PROGRAMS OVER 100 POPULAR PROMS & A EPROMS Standard Features: • RS232 Serial P$rt - Standard Formats • 5K Bytes RAM (Expandable) • Device Read, Compare & Verify • Editing & Special Functions • Less Than $1,000 for Programmer • Less Than $400 for Module and Adapter • Attractive OEM Prices REP AREAS AVAILABLE IBSDI COMPUTER SYSTEMS CORPORATION 100 E. Linton 81 vd Del ray Beach, Ra 33444 Phone (305| 272-20S1 COT***® m» Catalog today l^^.,^^ <{y \ Name- Company _ A Division o< Moore Business Forms Moore Computer Supplies Catalog Department 128 PO. Box 20 Wheeling, Illinois 60090 Address. City. _ State _ .Zip. Mail this coupon today! Circle 282 on inquiry card. April 1982 © BYTE Publications Inc 445 Circle 482 on inquiry card. • SOFTWARE toe new CP/M™ bus/ness & P^ofess/ona/ cafa/og This latest issue features professional software reviews on electronic work- sheets, word processors, accounting, and more. Convenient shopping at low mail order prices.., Packed with facts that give you the extra savings of smart product selection. Unique installation, systems, and for- mat charts assure you'll choose soft- ware that is easy to run on your configuration. > Our analysis of competing products help you to find the best software for your particular needs. • This unusual catalog contains over 15,000 words of succinct, hard-to-find data... and you'll be on our list for future catalogs as they are published. > Rush your request today and avoid the delays of catalog re-runs, There's no obligation. Send for your FREE catalog today! K^^PJWl BM0382 CORPORATION □ Send me SELECTED SOFTWARE FREE of charge, (Please Print) NAME: _____ ADDRESS: _________________ CITY/STATE/ZIP: DISK SIZE: _ 8" D 5.25" SYSTEM; RAM:_ _ I TERMINAL: PRINTER: Mail to: DEDICATED SYSTEMS CORPORATION 2440 E. Commercial Blvd., Suite 4 Fort Lauderdale, FL 33308 CP/M is a registered trademark of Digital Research Summary The transition from computer hob- byist to professional can be reward- ing in terms of both personal satisfac- tion and salary. The employment outlook for computer-related jobs is excellent. In the 1981 College Place- ment Annual more than 650 com- panies and government agencies ad- vertised for computer programmers, and that number is expected to in- crease. A variety of corporations are represented, from banks to large- scale manufacturing companies. Jobs are available in most locations in the U.S., with the greatest demand in large metropolitan areas. There are many jobs that involve programming — programmer, mathe- matician, computer scientist, and en- gineer. We have looked at the job Free Information 1981 Computer Salary Survey and Career Planning Guide: Source EDP, Suite 1100, 100 South Wacker Dr., Chicago, IL 60606 (or contact your local Source EDP Office). Mathematics and Related Positions (Announcement Ql-1500), Computer Specialists (Announcement 420), and other civil service job announcements: United States of America, Office of Personnel Management, 1900 E St., NW, Washington, DC 20415 (or con- tact your local Job Information Center). CLEP May Be For You; College Board Publication Orders, POB 2815, Princeton, NJ 08541. ACT Proficiency Examination Pro- gram; ACT PEP Coordinator, Profi- ciency Examination Program, POB 168, Iowa City, IA 52240. Benefits for Veterans and Service Per- sonnel with Service since January 31, 1955, and Their Dependents; Veterans Administration, 941 North Capitol St., NE, Washington, DC 20421. Occupations in Demand at Job Service Offices; Consumer Information Center, Pueblo, CO 81009. duties and some of the entrance re- quirements for these positions. Some require a bachelor's degree and knowledge of one or more program- ming languages, particularly COBOL and FORTRAN. Those interested in attending college to become profi- cient in programming have many op- tions to choose from, as an increasing number of schools offer suitable pro- grams. Once you are qualified, it is imperative that you develop your job-hunting skills so that you can pursue the career of your choice. ■ Acknowledgments / would like to thank White Sands Missile Range for providing the facilities to collect and develop some of the material presented in this article. References 1. Career Opportunity Update. Career Re- search Systems Inc., Huntington Beach, CA, July 1980. 2. College Placement Annual 1981. The College Placement Council Inc., Bethle- hem, PA, 1979. 3. 1981 Computer Salary Survey and Career Planning Guide. Source EDP, Oak Brook, IL, 1981. 4. Computer Specialists, Announcement 420. US Office of Personnel Management, Washington, DC, February 1977. 5. Dictionary of Occupational Titles, Fourth Edition. US Department of Labor Employ- ment and Training Administration, Wash- ington, DC, 1977. 6. Find Your Niche. The Retired Officers As- sociation, Washington, DC, January 1979. 7. Mathematics and Related Positions, Announcement Ql-1500. US Office of Personnel Management, Washington, DC, October 1978. 8. Occupations in Demand at Job Service Offices, Spring/Summer 1979. US Depart- ment of Labor, Employment and Training Administration, Washington, DC, 1979. 9. Occupational Outlook Handbook, 1980-81 Edition. US Department of Labor, Wash- ington, DC, 1978. 1 0. Out of the Service and Looking For a Job? Here's Help! US Department of Labor, Employment and Training Administration, 1977. it; We US Army Career and Educational Guide. US Army Recruiting Command, Fort Sheridan, IL. 12.1/eferans Employment Seminar Program Workbook, Third Edition. National Alliance of Business, Washington, DC. "IS. Washington Counseletter. Chronicle Guidance Publication Inc., Washington DC, March 1980. 446 April 1902 © BYTE Publications Inc Converting Apple DOS » and Pascal Text Files Now you can exchange information between DOS 3.3 and Pascal operating systems. John B. Matthews, MD 6415 Tantamount Lane Dayton, OH 45449 Wouldn't it be nice to use the Pascal editor on BASIC programs? Perhaps you would like to share Pascal programs with members of a user's group, but your newsletter editor or librarian prefers the text in DOS format. Maybe you can down- load FORTRAN programs via modem from the school computer. Unfortunately, Pascal doesn't rec- ognize your modem. Apple's implementation of UCSD Pascal is a real pleasure to use. At the same time, its disk operating system (DOS) is one of the more friendly and its BASIC is handy, if not especially efficient. Each system has its advan- tages and limitations and its own complement of editors and utilities to speed program development and text preparation. Still, there are occasions when you might want to move infor- mation from one environment to the other. Retype everything? No! Let the computer do the work. To see how this might be ac- complished, consider the organiza- tion of data on disks in the two systems. DOS 3.3 logically divides the disk into 560 sectors (35 tracks with 16 sectors each). Each sector contains 256 bytes of data. Pascal divides the disk into 280 blocks, each containing 512 bytes. A single DOS 3.3 sector and half of a Pascal block are physically (but not logically) identical. The solution to conversion revolves around this underlying similarity. All that is necessary is a map correlating DOS sector pairs and Pascal blocks. Listing 1 is a Pascal program called GETDOS. It reads DOS-format text files and writes Pascal-format files. The array MAP contains the informa- These methods may also apply to other operating systems, such as CP/M for the Z80 SoftCard. tion needed to decide which half- block to use for a given sector. The procedure READSEC reads the in- dicated block and, based on the MAP, decides which half to move in- to the TEXT array. The procedure GETNAMES prompts the user for source and destination units, as well as a file name. If your system has more than two disk drives, you may want to modify the CASE statement to recognize the extra units. Note that output to the CONSOLE: or PRINTER: is also supported. Reading the source file is a matter of searching the DOS directory for the indicated file name, getting its track/sector list, and reading the data one sector at a time. Appendix C of the DOS 3.3 manual gives details of the directory and file organization. Files that are not text type or are too large to fit in the Pascal editor are re- jected with an appropriate error message. Since DOS stores text as negative ASCII (i.e., with the high-order bit in each character set to 1) and the Pascal editor expects to see positive ASCII (i.e., the high-order bit clear), the characters must be converted. Writ- ing the destination file is handled two ways. If data are going to a disk file, the conversion is done once and the function BLOCKWRITE is used to speed up the transfer. If data are go- ing to the CONSOLE: or PRINTER:, conversion and output proceed simultaneously one character at a time. Files can be converted the other way, too. Listing 2 is an Applesoft BASIC program that reads Pascal files and writes DOS 3.3 text files. It bears the remarkably innovative title GETPAS. This program is organized along a line similar to its Pascal counterpart. The principal pro- cedures are set off with REM statements. Since BASIC has no in- trinsic procedure analogous to Pascal's UNITREAD, it calls the 6502 Text continued on page 457 April 1982 © BYTE Publications Inc 447 Listing 1: Program GETDOS is used to convert DOS 3.3 text files to Pascal format files. Reading the source file is a matter of search- ing the DOS directory for the indicated file name, getting its track/ sector list, and reading the data one sector at a time. The array MAP contains the information needed to determine which half-block to use for each sector. The CASE statement can be modified if your system has more than two disk drives. PROGRAM GETDOS j * * * Program to convirt DOS 3,3 text files to Pascal format files. * *************** **************^ CONST MAX. 18432, (36 blocks of 312 bytes is maximum EDITOR om load.) PAGEa256 , (DOS sectors are 2 5 6 bytes long.) CLEAREOL-29 ; C LEXRSCRE EN- 1 2 \ TYPE B¥TE«G . . 2 S. 5 y UNITS*! . 12 \ UNTYFED_FILE«FILE ; SECTOR.RECORD BLOCK : . , 7 t HALF: (FIRST, SECOND) END; VAR MAP: PACKED ARRAYE0..15 3 OF SECTOR; BUF. PACKED ARRAY E . . 5 i 1 3 OF BYTE; TEXT FACKED ARRA Y I . . MA X 3 OF BYTE; Learn about the Z8000 "from the people who are pioneering the Microworld. Zilog's Z8000 Architecture techniques of memory management, This course can make you an Course takes you into the world of methods for interfacing memory expert on Z8000 technology for only faster, smarter, smaller micro- and peripherals, plus use of the $39. Enroll today by sending us processors without leaving your ZSOOO's powerful instruction set, the coupon? Allow six weeks for home. Our five-part correspon- You study at your own pace. delivery of your first lesson, dence course covers the details of Each test is individually graded and the ZSOOO's 16-bit architecture, critiqued, then returned to you. ZHOQ Training and Education, 1315 Dell Avenue, Bldg. C, Campbell, CA 95008 Enroll me today in Zilog's Z8000 Architecture Course. D Enclosed is my check or money order (no cash or purchase orders, please) for $39. Make check payable to Zilog, Inc. Please charge my □ MasterCard or □ Visa account 00000000000 00000 Expiration date: Mo: Year: Signature BUSINESS ADDRESS Name Title Company Cit y /State/Zip_ ^_. _, Alt ^ M ^ MicroworMt cffe^ X_l I C\rt Pioneering Telephone. Area code number BILLING ADDRESS (as shown on charge card) Name _ An affiliate of E *ON Corporation Company Address . Zilog City/State/Zip s Please mail my lessons to: Business Address Billing Address *Offer expires August 27, 1982. Good only in the U.S. « 448 April 1982 © BYTE Publications Inc Circle 445 on inquiry card. Listing 1 continued: SQURCEFILE, DESTF1LE: STRING; SGURCEUNIT, DESTUNIT UNITS; DRIVES; SET OF UNITS; BLOCK- TRAK , SEC- BLOCKCOUNT, I: INTEGER; PTR : INTEGER; (POINTER TO TEXT ARRAY) DONE, FOUND BOOLEAN, CH : CHAR; F: FILE OF CHAR; (For use with CONSOLE: or PRINTER DISKFILE UNTYPED PILE; (For use with BLOCKWRITE) PROCEDURE INITIALIZE ; {For each of 16 sectors specify which block to read from} t a given BEGIN MAP C 3 MAP I i 3 MAP I 2 3 MAPC 3 '} MAP l 4 3 MAP I 5 3 MAP i 6 3 MAPC7J MAPI 8 3 MAP C 9 3 MAP C 1 3 MAPC 1 1 J MAPC 1 2 3 MAP [ 1 3 3 MAPC 1 4 3 track and which half to use as the sector BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK . BLOCK BLOCK , BLOCK BLOCK . BLOCK = = 7 = 6 m 6 = 4 = 3 = 2 = 2 = 1 ■ 1 = MAPC 3 . MAP C 1 3 . MAP [23. MAP C 3 3 . MAP C 4 3 , MAP i 5 3 MAP t 6 1 MAPC 7 3 . MAP r 8 3 . MAPC 9 3 . MAPC 1 3 MAPC i 1 3 MAPC 1 2 3 MAPC 1 3 3 MAPC 1 4 3 HALF HALF HALF HALF HALF HALF HALF HALF : HALF ; HALF : . HALF . HALF HALF . HALF HALF *F IRST ; =FIRST ; =SECOND ; =FIRST, =SECOND ; =FIRST) =SECOND , =F1RST; =SECOND ; =FIR5T, =SECOND, =FIRST ; ^SECOND ; =FIRST , ^SECOND ; Listing 1 continued on page 450 A REFURBISHED DAISY WHEEL TERMINAL FOR PERSONAL COMPUTER USERS AND SMALL BUSINESSES. Now you can have letter-qualit y printin g and prof essional features for just $1,495? AJ daisy wheel printer terminals are renowned for exceptional performance, high reliability, and applications versatility. Now you can have all this for only $1,495* in our special limited offer. • 30 cps letter-quality printing J • Changeable type faces > Full ASCII keyboard with numeric pad • High resolution X-Y plotting • Complete electronic forms control • 128-character buffer • Asynchronous RS-232 interface • Printwheel, ribbon cartridge, and cable included • 30-day parts/labor warranty And you can choose from a list of options including forms tractor, pin-feed platen, paper trays, side shelves, extra printwheels, APL keyboard and 2K buffer Call your nearest AJ regional . office for details: San Jose, CA JB f' f f 1 f f I M I Ti I I 1 my i ' l ii yi fl v^^-^v^v'--- , -;--|liM\\ •Price excludes options and is subject to change without notice. Model shown includes certain options. Offer available only in the contiguous U.S. (408) 946-2900; Rosemont, IL (312) 671-7155; Hackensack, NJ (201) 488-2525. Or check the phone book for the number of your local AJ sales/service office. Call Toll Free Now: 800-538-9722 In California: (408) 946-2900 ANDERSON JACQB5QN Circle 30 on inquiry card. April 1982 © BYTE Publications Inc 449 Listing 1 continued: MAPI 15 3. BLOCK : = END ; {INITIALIZE} MAP C i 5 3 HALF : = SECOND PROCEDURE PR I HTAT < Y BEGIN GOTOXY ( , Y> PROCEDURE GETNAMES j VAR OK: BOOLEAN; DEST BEGIN DRIVES : =[ 4 , 5 3 . ; REPEAT WRITE(CHR( CLEAR SCREEN) ) INTEGER; 3: STRING) WRITE C CHR ( CLEAREOL) STRING , S> END; PR I NT AT ( 2 , PR INTAT< 5 i PRINTAT ( 6 , PR I HTAT ( 8 , PRINTAT( 1 PR I HTAT < 1 2 DESTF I LE IF FOSC ' Ha t t h ews , Drive #4 P r inter : ! *** GETDOS *** By John Units: i . Console: 4 5 Drive # 5 : 6 Source Unit (4-5) '); R EADLN ( SOURC EUN I T ) \ 'Destination Unit Ci-6): '); READ LN < DE3TUN IT > ; , 'Source file name: '), R EADLN ( SOURCEF I L E ) , SOURCEFILE; STR < DE5TUNIT . DEST > \ , SOURCEFI LE > =0 THEN DE STF I L E : =CONC AT ( SOURC E F I L E TEXT' > j CASE DESTUN1T OF 1 : DESTF I LE 2: DESTFILE 3 : DESTFILE 4,5: DESTF I LE : 6 DESTFILE : = ; 7,8,9,10,11,12 END CONSOLE : ' j 3YSTERM: " ; HOT AVAILABLE " ; =CONCAT( ' * ■ ,DEST , PR INTER : ' ; : DESTFILE :* 'NOT DESTF I LE > IMPLEMENTED {CASES of DESTUNIT) NEW & USED Terminals— Printers— CRT's— LSI— Boards— Misc. 9x9 Matrix, 80/132 Col., Friction/Pin Feed, 4 Part Forms, 200 Million Char, Bi-Direct Print VIDEO TERMINALS NEW-USED Lear ADM-3A NEW $ 575 LearADM-3A USED 395 Beehive B-100 USED 295 Televideo912-B USED 395 TERMINALS & PRINTERS MISC. NEW OKIDATA83-A $699.00 Tractor $49.00 Tl 810-100 $1225 Tl 810 Pdg w/tray. 1339 Tt 785 APL 1925 Tl 783 KSR 1325 Tl 765 20K : 2295 TELEVIDEO NEW TVI 950, . . $~~865 ! TVI 920C. . 695 * TV) 912B. . . . 655 j FLOPPY DISCS Techtran 951 $1395 Techtran950 1065 TAPE DRIVE EIA NEW Techtran 8421 Dual Tape $1395 Techtran 8420 Dual Tape 1200 Techtran 8400 Single Tape 995 Techtran 818 Single Tape 1255 Techtran 817 Single Tape 1295 TAPE DRIVE EIA USED Techtran 815 Single Tape. Techtran 817 Sinale TaDe $ 495 975 MODEMS AND COUPLERS USED AJ ADAC 1200(1200 Baud) $ 450 Anderson Jacobson 1258 . 695 MODEMS AND COUPLERS NEW AJ ADAC 1200(1200 Baud), Ventel 103 Coupler A J 242-A 300 Baud $ 350 100 110 Execuport 3000 USED $1095 Execuport 300 USED 595 TI733ASR USED 695 Teletype 43AAA USED. . 775 DEC LS-120 (120 CPS) USED , 795 DEC LA-36 DK Refurbished 595 Diablo 1641-1 USED 1450 1620-1 USED 1395 1660-1 USED 595 (Like DEC LA-120) Computer Devices 1132 Refurb 7 50 VT-100 NEW. $1 VT-52 NEW 1 LA-180 NEW LA-180 USED LS-120 NEW ! LA-120 NEW 2 LA-34DA NEW Interface LA-180 RXO1K-10 Pk of Diskettes $ 45 RLV21-AK Disk Drive & Ctrl (10 Meg) 3300 RLV11-AK Disk Drive & Ctrl (5 Meg) 2900 RL02-AK Disk Drive (10 Meg) 3000 RL01-AK Disk Drive (5 Meg) 2500 QJ628-GZ RSX11-M Documentation. ... . 200 QJ813-GZ F4/RT11 Doc. Kit 22 QJ013-GZ RT 11 Doc. Kit 130 PB11K-AA 630 MXV1 1-AA Multi-Mod-8K 450 MXV11-A2 22 MSV11-DD 760 KWV11-A 512 KDF11-RG. . 2880 KD11-HD 995 KD11-GF 695 IBV11-A 480 H9273-A 345 H9270 99 H780J 395 DUV 11-DA 470 DRV11 135 MS11-MB $3990 MS11-LD 2240 MS11-LB 1710 MK11-CF. . . 19950 MK11-BF 8160 MK11-BE , 6750 DR11-C 435 DL11-WA 596 DH11-AD 6375 DD11-CK 299 BA11-KE 2398 DLV11-F 159 BCV1B-06 175 BA11-NF 998 BA11-NE 998 ADDS 200 $ 695~ ADDS 580 795 ADDS 980 1395 ADDS 20 450 ADDS 25 495 ADDS 40 650 ADDS 100 650 OMNETEC 401 C 115 OMNETEC710. 100 OMNETEC 736 100 TERMINAL BROKERS CO. 2001 West Main St. Suite 304, Stamford, Ct. 06902 203-964-9331 Limited Quantities Add $15.00 per unit UPS charge MASS, NJ, NY, ILL, CAL, CONN, GA, OHIO Add Sales Tax. Circle 411 on inquiry card. USED TUBES & COUPLERS 450 April 1982 © BYTE Publications lnc Listing 1 continued: PR I NT AT < 1 4 , CONCATC 'Destination file: ', DESTF I LE ) > ; PR INTAT< 1 6 , ' < cr > accepts, exits, restarts READ (KEYBOARD, CH) ; OK : = EO LN ( KEYBOARD > ; IF CH IN C J E ',' e ; ,CHR< 27 > 3 THEN E X I T < PROGRAM ) ; UNTi L OK i END ', (G ETHANES} PROCEDURE READSEC ; BEGIN BLOCK: = (TRAK*8 > +MAFCSEC3 BLOCK; UNITREAD(SOURCEUHIT,BUF ,512, BLOCK) ; CASE MAPCSEC3 . HALF OF FIRST: NOVELEFTCBUFL 3 , TEXT t PTR ] , PAGE) j SECOND MOVE LE FTC BUFCPAGE3 , TEXTC PTR 3 f PAGE ) END, (CASES of MAP) PTR : =FTR + FAGE j EHD ; tREADSEC} PROCEDURE READSOURCE j CONST BYTE3_FER_ENTRY= 35 BLANKS= ' VAR NAME. STRING C30 3; FILETYPE , SECTORCOUNT, ENTRY: PACKED ARRAYL 1 . . BO , HEADER** i 1 L IMIT L I ST : BEG IN {Read £ 21 B 1 anks } BYTE \ INTEGER ; 13 OF BYTE cataloa from track 17; sectors 1 1 > FRINTAT* i Readino catalog Listing 1 continued on page 452 NEW* APPLE II PRODUCTS * DUAL COMM PLUS™ TWO SERIAL PORTS V0 * Two fully independent serial I/O ports Combines the features of trie APPLE HIGH SPEED SERIAL CARD™ and the APPLE COMMUNICATIONS CARD™ in one card (with handshaking) Thumbwheel switches select the Apple slot locations. Sixteen switch selectable baud rates tor each port (50 to 19200 baud) On-board firmware provides extensive printer and U/L case terminal/modem support. Great with an 80 x 24 card and a Novation CAT or Hayes Smartmodem Can be programmed for async., sync, or even SDLC operation. Supports interrupts Uses Z80 SI0 chip. LIST PRICE: $239.00 MANUAL ONLY; $15.00 * MEMORY PLUS ™ 16K RAM EXPANSION Add another 16K to your 48K APPLE Works with PASCAL. DOS, CP/M, FORTRAN. COBOL, PILOT, Personal Soft- ware's VisiCalc. INTEGER and APPLESOFT BASIC Many other Apple software packages benefit from the additional storage provided by the MEMORY PLUS card. Three LED's show memory select and read /write protect status Toggle switch to shut the card off or to select between the standard monitor ROM or the on-board firmware socket. The firm- ware socket can hold an alternate Apple monitor ROM or a 2716 program (user provided). LIST PRICE: $149.00 MANUAL ONLY: $15.00 Alt Bit 3 Apple products features: • Easy plug-in installation • Operation with PASCAL Z80 S0FTCARD™, APPLE II and APPLE II PLUS • 50/60 hz operation FULL-VIEW 80 ™ 80X24 0* MasterCard) • Permits selection of 80 column or Apple 40 column/graphics on a single monitor via keyboard or program control • 8 x 10 cell size upper/lower case character set witfi full lower case decenders • User definable ER0M character sets via 2716 (127 chars) or 2732 (255 chars) • On-board 2K firmware supports HTAB, VTAB, U/L case keyboard, DATAMEDIA CONTROL COOES, INVERSE/NORMAL VIDEO, and a special printer driver • Low power requirement • Easy installation - just plug it in! • Compatible with many 80 column word processors • Compatible with the DC. Hayes MICROMODEM™ LIST PRICE: $379.00 (2716 std. char set) MANUAL ONLY: $15.00 BIT 3 COMPUTER CORPORA TION 8120 Penn Avenue South • Suite 548 Mpls.,MN 55431 -(612)881-6955 Apple II is a registered trademark of Apple Computer. Inc.; Z-80 Softcard is a registered trademark of Microsoft Consumer Products. DC. Hayes Micromodem is a trademark of DC. Hayes, Associates, Inc.; Novation CAT is a registered trademark of Novation, Inc. Circle 55 on inquiry card. April 1982 © BYTE Publications Inc 451 Listing 1 continued: TRAK ■=!?; PTR : = ; (Start at beginning of TEXT} FOR SEC =15 DOWNTO 1 DO READSEC; (Find sourcei ile entry} LIMIT: = PTR- I ; PTR =HEADER; ENTRY : m ; SOURCEF I LE ; =CONCAT( SOURCEFI LE , ' \); (Make name unique) REPEAT NAME =COFY ( BLANKS , 1 , L ENGTH ( SOURC E F ILE) ) j ENTRY ■ =ENTRY+ 1 , FOR I:= i TO LENGTH* SOURCEF I LE) DO NAMEE 13 .«CHR(TE XT CPTR +1*23-128) ; FOUND ■ s NAME-SOURCEFILE ; IF NOT FOUND THEN (increment PTR} BEGIN IF (ENTRY MOD 7)=0 THEN PTR : = PTR +HE AD ER ; PTR »FTR+BYTES_PER_ENTRY END; UNTIL FOUND OR LIMIT>; IF (still) NOT FOUND THEN BEGIN FRINTAK18, 'File not found... 1 ); E X I T ( RE ADSOURCE ) END, TRAK: =TEXTEFTR3 ; S EC : =TE XT C PTR+ 1 3 j (Looition of track/sector list) FILETYPE : -TEXTCPTR+23 ; (0 if unlocked TEXT; 128 if locked TEXT) SECTORCOUHT: *TE XT C PTR + 3 3 3- 1 ; (Minus 1 for the track/sector list) IF i < FILETYPE< >0 ) AND ( F I LETYP E < > 1 2 8 ) ) OR ( S ECTORCOUNT > 7 2 > THEN BEGIN FOUND . = FALSE j FRINTATC 18, 'Not a TEXT file. ..') ; EX IT! READSOURCE ) END ; (Read the track/sector list) PTR:=0- READSEC; PTR : = 1 2 ; (list starts at byte 12) FOR I : * 1 TO SECTORCOUNT DO BEGIN LI ST CI, 03: =TEXTCPTR 3 j PTR : =PTR + 1 , YOU'VE NEVER SEEN DISCOUNTS LIKE THESE! SYSTEM THREE $5999 CROMEMCO SYSTEM ONE $2999 SYSTEM 1H 5395 '*• SOROC IQ130 3» IQ150 $ 699 1395 MORE SPECIALS SYSTEM TWO $3995 SYSTEM Z2H 7495 VIDEO TERMINAL 3102 $2099 MAXELL DISKETTES Boxes of 10 MD1 MD2 $39.95 49.95 FD1 FD2 $42.95 57.95 ATARI 800 $ 699 Tl 810 Printer 1349 QANTEX Printer 1049 ADDS Viewpoint 599 ADDS Regent 25 879 EPSON MX80 $ 499 EPSON MX80 FT 599 EPSON MX100 759 MALIBU 2599 DEC LA34 949 CALL FOR INFORMATION ON NORTHSTAR, HAZELTINE, LEAR-SIEGLER, QUME, INTEGRAL DATA SYSTEMS, OKIDATA, TELEVIDEO, DIGITAL MICRO SYSTEMS All prices are CASH. American Express, Visa, Master Card, add 5% Prices subject to change without notice DATA DISCOUNT CENTER P.O. BOX 233, Greenvale, New York 11548 516-869-8537 452 April 1982 © BYTE Publications Inc Listing 1 continued: LI STL I , 13: =TEXTCPTRJ ; FTR =PTR+i END ; (Finally, null the TEXT buffer and read the data) IF ODD(SECTORCOUNT) THEN B LOCK COUNT : = < SECTORCOUNT+ 1 ) DIV 2 ELSE BLOCKCOUNT : =S ECTORCOUNT DIV 2, F ILLCHAR (TEXTL03 , BLOCKCOUNT* 5 1 2 , CHR < > > ; PR INTATC 18,' Reading file..'); FTR : =0 ; FOR I : m X TO 5ECTQRC0UMT DO BEGIN TRAK:=LISTEI ,03 , SE C : m L I ST t I , 1 3 \ READSEC END; END ; tREADSOURCE > on line press ) ) PROCEDURE VRITEDEST; VAR NEXTBYTE: BYTE; BEGIN PTR : =0 i PR INTA7 < I 8 , CQNCATC 'Put ' , DESTF I LE READ 1 27 THEN TE XT E I 3 : =TE XTE I 3 - 1 2 8 ■ FR INTAK 1 8 , CONCAK 'Writing to \< DESTF ILE , ' ...')> ; REWRITE (D I SKF I LE , DESTF ILE > ; I sBLOCKWR ITE (DISKFI LE , BUF , 1 f > , (Tent file header} I:=BLOCKVRITE(DISKFILE,BUF,l, 1); CText file header} I : =BLOCKWR ITE (DISK FILE .TEXTC 03 f BLOCKCOUNT, 2 > Listing 1 continued on page 454 ORDER: 1-800-547-2492 IN OREGON CALL SERVICE: 503-479-4150 ATARI'A 400 (16K) 800 (16K) $325 $675 EPSON MX-70 $369 MX-80 $459 MX-80FT $559 MX-100 $739 OEM-MX-80FT $525 OEM-MX-80 $425 OEM-MX-100 $709 I.D.S. 445G Printer $689 460G Printer $799 560G Printer $999 OKIDATA 80 $389 82A $539 83A $829 84 $1229 WORD PROCESSOR PACKAGE WORDSTAR, 80 Column, w/enhanced character set, Z-80 & 16K Card by ALS $1049 OLIVETTI 121- PRINTER/TYPEWRITER w/Magnum RS 232 or Parallel $1495 APPLE HARDWARE MICRO SCI DISK DRIVES (IHREXI APPLE REPLACEMENT) A 2 DISK HKIVt A 70 A 40 CONTROLLER 3.3 & 3.2 ( ( s 77IOA St RIAL INT CCS 77 1 0D SLRIAL INT VIDEX 80COI IIMN VIDEX ENHANCER II LOWER t ASL ADAPTOR W.K RAM CARD MICROSOF I OK MP( ALS / 80 CARD (MICROSOF I j MIC ROMOIH M (HAYES) SMART MODEM (HAYES) NOV AT ION MODEMS APPLE CA1 AUTO CAT CAT D CAT BI/COMP MODI M MOUNTAIN CLOCK MOUNT AIN MUSIC SYSTEM MOUNTAIN A/D CONVERTER MOUNTAIN INIROL/X-IOCARD MOUNTAIN C.RS, KBD 23 Kl.\ PAD SUP-RTERM (SO COLUMN) SUP-R-MOD R.F. MODULATOR 12" B&W MONIIOR (SANYO) 12"GREEN MONIIOR (SANYO) 1 2" GREEN MONITOR /ENIIlf) 13' COLOR MONITOR SANYO) EPSON CABLE A INTERFACE EPSON <,RAT TRAX POWERLINF PROTECTOR ATARI HARDWARE 410 PRO«>KA\1 RE $369 820 PRINIER 822 PRINTER (249 $139 R25 PRINT ER $5 7') $139 830 MODEM $149 %!(><■) 850 INTERFACE MODULE $13 5 $139 ,SS1 D,K MEMORY EXPANSION $?■> $39 $!4 \ END; CELBE) END ; {WRITEDE3T} , DESTFILE ( ' ) > BEGIN (MAIN PROGRAM) INITIALIZE (sector/block map); REPEAT GETMAMES (and locations of files), READSOURCE tin DOS format) , IF FOUND THEN WRITEDEST; WR ITELK , WRITELN , WRITE C ' Ano t her file 1 (Y/N) ' > ; READ (KEYBOARD , CH > \ DONE : * CH IN C ' N ' , ' n ' 3 ; UNTI L DOME END (MAIN) Call ME. Incredible savings are just a phone call away with the Morgan Electronics hot line. SAVE $800 on the TRS-8CP 48K Model III computer. Limited supply available. In- cludes all the standard basic features of the TRS-80® Model III with 48K of RAM and disk expansion Kit III™ with two 40 track double den- sity disk drives. Completely compatible with TRSDOS™ and all TRS Model III operating systems. Total Price $1,695 00 Also available — TRS-80* Model III same as above with two 80 track disk drives for only $2,1 45 00 . ALL PRODUCTS BACKED BY A 90-DAY WARRANTY TRADEMARKS: TRS-80 and TRSDOS'Radio Shack/Tandy Corp. LDOS/Logical Systems, Inc. Kit Ill/Morgan Products, Inc. SAVE OVER $1,000 on the ME I Word Processing System— TRS-80* 48K Model III and Olivetti Daisy Wheel Printer. Includes Software Kit. Total Price $3,695 oo ZilfiX MORGAN Call TOLL FREE (800) 851-4614 In Illinois Call (618) 233-0018 Morgan Products Incorporated 104 Berkshire Drive Belleville, Illinois 62223 We accept: Visa, Master Charge, Certified Checks {Personal checks require three weeks clearance), Money Orders and C.O.D. 454 April 1982 © BYTE Publications Inc Circle 283 on inquiry card. Listing 2: The Applesoft BASIC program GETPAS is used to convert Pascal text (.TEXT) files to DOS 3.3 text files. The Pascal volume directory is read from blocks 2 through 5 to find the indicated file name. Since BASIC does not have an intrinsic procedure analogous to Pascal's UN IT READ, GETPAS calls the machine -language routine shown in listing 3. i REM GETPAS; PASCAL TO TEXTFILE CONVERSION 2 REM By J. Matthews, MD 7/6/8 1 3 GOTO 200: REM START OF MAIN PROGRAM 4 REM *** SUBROUTINES *** 1 1 5 1 X 1 1 5 12 1 2 5 REM WR ITE FILE CH m PEEK C I > IF CH = 16 THEN FOR J = 33 TO I F CH m AND I IF CH = THEN (SKIP HULLS) I m I + 1 : CH = : PEEK < I > : PR INT " " > EN THEN RETURN 1=1+1: GOTO 1 5 I F PEEK < I > > NEXT J : I 32 I THEN + i : GOTO 105 PRINT CHR$ (CH) GOTO 105 1 30 REM 135 SL% m 1 4 TR : 1 5 5 GOSUB 190: BU% ■ 1 6 SEWo m Whi PT INT ( (BLOCK / 8 - TR%> CALL RVTS BU% 4 PAGE CALL RVTS BU% + PAGE 8 ) 175 REM CENTER TITLE 180 HTAB 20 - LEN PRINT T* . RETURN 185 REM ERR TRAP 190 IF ER% < > THEN PRINT "DOS ERROR 195 RETURN VTAB 20 . " : POP CALL POP - 8 6 6: GOTO 2 9 2 00 205 21 1 1 8 220 225 230 235 240 245 250 25 5 2 6 2o3 REM *** INITIALIZE *** RWTS m 1638 4 HI MEM: RWTS PRINT CHRI <4>,"BLOAD RWTS FACE - 256 BU* - RWTS * BEG - BU%:EW MVo K , > Wh i 1 , > M*p ( 2 , ) MVi» (3,0; M»A> (4,0) n% t s t o ) H% ( 6 , i Wki 7 , > PAGE ; CM% ■ 1 m BU«t * PAGE :M%< , 1 > ■ i 4 1 3 : M* < 1 , 1 > - 12 n : nm c % , 1 * ; m* i I f % ) n% ( 4 i i > H% < 9 f I ) Wt ( 6 , 1 > tm < 7 , i > . i o i 4 4 2 IS OBJ0 " 2 70 REM *** GET FILE NAMES * * * $75 HOME' 2*0 T* - '* 2 65 Ti ■ " 290 VTAB 29 5 PRINT 300 HTAI VTAB 3 '*** CONVERT: PASCAL BY JOHN MATTHEWS, M 8 ; HTAB 1 "SOURCE &IQT ! 6 M l PEEK ( 36 > : GET INI TQ TEXT ***** { GOSUi I 80 D . " ; GOSUB 1 BO PRINT Listing 2 continued on page 456 April 1982 © BYTE Publications Inc 455 Listing 2 continued: 30?> SB m VAL UNI) 3 10 I r HI * THEN sa ■ 6 31 & IF SS < OR SS > 7 THEN 29 320 PRINT SS 320 VTAB 10: HTAB 1 330 PRINT "SOURCE DRIVE: i", 335 HTAB PEEK <36>: GET INt 340 SD = VAL ( IN* ) 345 IF SD x THEN SD x 1 350 IF SD < 1 OR SD > 2 THEN 325 355 PRINT SD 36 VTAB 1 2 : HTAB 1 365 PRINT "DESTINATION SLOT. 6"; 370 HTAB PEEK (36): GET INS 375 DS - VAL C IN* 3 380 IF DS = THEN DS = 6 3S5 IF DS < 1 OR DS > 7 THEN 36 390 PRINT DS 3 95 VTAB 1 4 : HTAB 1 400 PRINT "DESTINATION DRIVE: 2"; 405 HTAB PEEK (36): GET IN* 4 1 DD x VAL < INS > 4 15 IF DD = THEN DD = 2 4 20 IF DD < 1 OR DD > 2 THEN 3 95 4 25 PRINT DD 430 VTAB 16, HTAB 1 435 INPUT "SOURCE FILE: ";SFS: IF LEN(SF$)=0 THEN 430 440 VTAB i 8 : HTAB 1 44 5 INPUT "DESTINATION FILE: ";DFS 450 IF LEN CDF$> = THEN DF $ x SF$: VTAB 18: PRINT "DESTINATION FILE: ",DFS 455 L2 x LEN < SF* > 460 VTAB 20: CALL » 868 PRINT "PRESS TO PROCEED; TO END " } . GET INI: IF IN* * CHR $ (27) THEN 605 46 5 PRINT ; IF INS < > CHR % (13) THEN 290 4 70 IF SD = DD THEN VTAB 20: PRINT "INSERT THE SOURCE DISK; PRESS " > : INPUT " " >IN* 475 REM *** GET DIRECTORY *** 480 VTAB 20 CALL - 868 PRINT "READING DIRECTORY.,." 485 BUfc x RWTS + PAGE: FOR BLOCK m 2 TO 5 : GOSUB 135; NEXT BLOCK 49 EN - BUVo 495 REM *** FIND FILE NAME *** 500 FOR I = BEG TO EN STEP 2 6 : NA $ x 505 SB x PEEK it) + 256 * PEEK : NB x PEEK (1+2) * 256 * PEEK (1+3) Li ■ PEEK < I + 6 > 510 IF LI < > L2 THEN 5 25 515 FOR* J x r + 7 TO T + L 1 + 6 : NA $ m NA $ + CHR$ < PEEK >: NEXT J 520 IF NA* = SFS THEN 540 52 5 NEXT I 53.0 IF NA* = "" THEN VTAB 20: CALL - 868: PRINT "FILE NOT FOUND: PRESS ";: INPUT " ";IN$: GOTO 290 535 REM *** READ SOURCE *** 540 VTAB 20: CALL - 868: PRINT "READING FILE. . . " 54 5 SB ■ SB + 2 : EB - NB - 1 : BU% « RWTS + PAGE 456 April 1982 © BYTE Publications Inc Listing 2 continued: 5 m J0 FOR BLOCK - SB TO EB: GOSUB 135: NEXT BLOCK 5*5 IF SD « DD THEN VTAB 20. CALL - B68: PRINT "INSERT DESTINATION DISK; PRESS 5 60 ■ INPUT " M ; INI REM *** WRITE DEST *** 56 5 5 7 57 5 560 585 590 5 95 600 605 VTAB 20 : CALL PRINT CHRt ( 4 ) PRINT CHRt 14) PRINT CHR$ < 4 > PRINT CHR* (4) I = BEG : EN * BU»* PRINT CHRt (4> VTAB 20 : CALL GET INI; IF PRINT END 848 "OPEN " "DELETE "OPEN " '•WRITE - PAGE: "CLOSE - 868 IN* ■ PRINT " ;DFI i M "iDPI DFt i " ,DF* GOSUB iDFI "WRITING M rO" ;DD DD 1 05 PRINT "ANOTHER FILE (Y/N) Y H THEN 2 70 Text continued from page 447: machine-language program found in listing 3, that in turn calls the read/write track and sector (RWTS) routines from DOS. (See the DOS 3.3 manual, page 94.) The Applesoft PTRGET routine is used to allow passing variables by name rather than by location using the traditional PEEK and POKE. The Pascal volume directory is read from blocks 2 through 5 of the disk. It is organized as 26-byte records, the first of which is the volume name: Directory record Starting block: integer; Next available block: integer; File type: integer; File name: string[15]; I/O designation: 0..255; Date: packed array occupying 2 bytes; end; Deleted files are marked by setting the length byte of the name string to 0. In reading the file itself, note that text files have a two-block header that ordinarily contains editor set- tings like environment and markers. The header can be skipped. Writing the file requires, once again, that the high-order bit of each character be reset. This is done with the standard Applesoft function CHR$. This method is rather slow, but trying to implement a "BLOCK- WRITE" function in BASIC would re- quire writing to both the disk direc- tory and the volume table of con- tents. This is more safely left to DOS. To mark the end of file, DOS uses the null (ASCII 0) character. Pascal uses Listing 3 begins on page 458 these to fill in the unused portions of blocks. Intervening nulls are simply bypassed as the file is written. One further conversion is helpful here. Pascal source lines that are indented are preceded by the data link escape (DLE, ASCII 16) character followed by a single byte specifying the number of spaces to indent plus 32. Without converting these to spaces, the indentation of Pascal text would be lost. These methods may also apply to other operating systems, such as CP/M for the Z80 Softcard from Microsoft. If the directory and sector organization can be found, the con- version is possible. These are the tools. Now you have one less excuse to keep your favorite Pascal programs tucked away in the back of a box.B JAY WEINBERG: LIVING PROOF YOUR CONTRIBUTIONS COUNT. These days, Jay Weinberg's most difficult battles take place on the tennis court. Five years ago, he had a different kind of fight on his hands: against one of the toughest forms of cancer. Cancer research and treatment have made Jays kind of recovery possible for almost 2 million people. Which means that your donations have helped buy Jay Weinberg a very beautiful gift: his life. CANCER CAN BE BEAT. American Cancer Society * April 1982 © BYTE Publications Inc 457 Listing 3: A 6502 machine-language routine to interface the BASIC program of listing 2 with the read/write track and sector routine of DOS 3.3 for direct control of disk access. More information on the RWTS routine can be found in the DOS 3.3 manual 00 0000 0000 000 0000 000 00 00 0000 0000 0000 0000 00 00 00 00 0000 00 00 00 00 4000 A 00 40 4 00 4000 000 l * RWTS INTERFACE FOR APPLESOFT BASIC Ma t thews , H . D 7/6/1981 Variables passed by name SL% = DR% = TR% = SE% = CM*A = BU% = 6 7 8 9 1 1 1 i 2 1 3 1 4 1 5 1 6 i 7 1 & 1 9 20 * NEXT OBJECT FILE NAME 2 1 22 2 3 2H 2 5 26 SLOT NUMBER DRIVE 1 OR 2 TRACK TO 3 4 SECTOR TO 1 5 (NULL : NO ACTION) 1 (READ A SECTOR) 2 (WRITE A SECTOR) 4 (FORMAT THE DISK) ADD. OF 256 BYTE BUFFER * Returned ER%= DOS ERROR CODE (0=NONE> I S ORG MSB RWTS . OBJQ $ 4 OFF I/O Block offsets: DOS 3.3 manual p94-98 IBSLOT EQU $ 1 ; SLOT OPTIONS 1. Processor • Z8001 • 68000 2. Disk Controllers • Floppy disk controller • Winchester disk controller 3. Memory • Memory boards from 32Kto512K • Either processor can address up to 16 Megabytes 4.1/0 • Standard serial I/O board with 8 RS-232 I/O ports • Intelligent I/O board with 8 ports, 16K dual port buffer memory, and an 8-bit I/O processor on board • Parallel I/O board with 80 bits of parallel I/O 5. 15 slot mother board 6. Heavy duty power supply • + 5 volts at 40 amps • +/- 12 volts at 3.5 amps each 7. Meets IEEE Multibus Standard 16 Bit Systems Z8000 or 68000 COMPUTEX MICROCOMPUTER SYSTEMS V 5710 Drexel Avenue Chicago, Illinois 60637 312 684-3183 TYPICAL SYSTEMS System 3 (Z8001 based) $7053 Includes: • 28001 processor with memory management • 256K RAM • 8 serial I/O ports • Floppy disk controller • ZMOS multiuser operating system • Dual 8 inch double density floppy disk drives • Case and power supply System 4 (68000) based $7099 Includes: • 68000 processor (8mhz) • 256K RAM • 2 serial and 4 parallel I/O ports • Floppy disk controller • Dual 8 inch double density floppy disk drives • Operating system • Case and power supply WINCHESTER DISK SUBSYSTEMS 1. 20 Meg 8 inch drive with dual case, power supply, and electronic module $3398 2. 20 Meg add-on 8 inch drive $1898 3. 60 Meg 8 inch drive with dual case, power supply, and electronic module $5898 4. 60 Meg add-on 8 inch drive $3598 458 April 1982 © BYTE Publications Inc Circle 122 on inquiry card. Listing 3 continued: 0002 0003 000 4 0005 0008 oooc 00OD OOOF 00 10 4000 4000 4000 00 IE 0048 0083 0OB8 4000 4000 4000 3D9 03E3 4000 4000 4000 DFE3 4000 4 00 20 E3 03 27 28 29 30 31 32 33 34 35 3d 37 38 39 40 4 1 42 4 3 44 4 5 46 47 4 8 4? 50 5 1 52 5 3 IBDRVN IBVOL IBTRK IBSECT IBBUFP IBCMD IBSTAT IOBPSN IOBPDN * Page * TPSAV IOB VARPNT TXTPTR * * DOS EQU EQU ECU EQU EQU EQU EQU EQU EQU $ 02 $ 03 $ 04 $05 $ 08 *0C SOD $ OF $ 10 DRIVE VOLUME TRACK SECTOR BUFFER POINTER COMMAND ERROR * PREVIOUS SLOT PREVIOUS DRIVE zero locati ons EQU EQU EQU EQU hooks RWTS EQU GETIOB EQU * * Applesoft S IE $ 48 $ 83 *B8 * 3D9 $ 3E3 PTRGET rout me PTRGET EQU SBFE3 ENTRY JSR GETIOB ;GET I/O BLOCK ADDRESS Listing 3 continued on page 460 CPISODC THE VERSATILE COMPUTER 11 ;,..,... p. ' ■ ■'■■ ■;»■■■ ' . ■ -■ ' ■?- 1 .;■ ■ ■' — ' ■ JUST ADD PERIPHERALS EPISODE is a CP/M "comput- er with 1.6 M byte of disk storage on dual 5Va flop- pies. Its compact design provides a wide range of standalone or network appli- cations including data base sharing. EPISODE gives you total flexibility. You can add your own CRT and Printer, what- ever brand and price range you choose. All the logic in- cluding the 64K RAM mem- ory is contained on a single 6" x 8" circuit board ensur- ing maximum reliability. •Supervyz is a trademark of Epic Computer Corporation. CP/M is a trademark of Digital Research. EPISODE includes a unique software system called SUPERVYZ™ - a menu based software control sys- tem that allows the user to integrate application pro- grams. Dealer inquiries invited, foreign and domestic. | |SYSTEIVIS Epic Computer Corporation 7542 Trade Street San Diego, CA 92121 Tel: 714-695-3560 Model 953A EPROM PROGRAMMER • Programs 2508, 2758, 2516, 2716, 2532 and 2732 five volt EPROMS. • Complete ■ no personality modules to buy. • Intelligent - microprocessor based, programs and verifies any or all bytes. • RS-232 serial interface use with computer or terminal, • Verify erasure command - verifies that EPROM is erased. • Extended diagnostics - error output distinguishes between a bad EPROM and one which needs erasing. • May be used for extremely reliable data or program storage. • All power on programming socket under processor control. LED warning light indicates when power is applied. • Complete with Tex tool zero insertion force socket. • High performance/cost ratio. • Standard DB 25 I /O connector. •f> PRICE $289 BAY TECHNICAL ASSOCIATES, inc HWY. 603. P.O. BOX 387 BAY ST. LOUIS, MISSISSIPPI 39520 (601)467-8231 Circle 173 on inquiry card. Circle 51 on inquiry card. April 1982 © BYTE Publications Inc 459 Listing 3 continued: 4003 4005 4007 4009 400B 400D 400F 4012 4013: 40 14 40 15: 4 16: 4013: 4 1 A ; 4 1 D : 4 1 F . 4021 : 4 2 3 : 4025 : 4027 : 402A : 4 2 C ■ : 402E : 4 3 1 ; 4033 : 4 3 5 : 8 4 . 85 A5 : 85 : AS : 8S : 20 . 0A : OA : OA : OA : AO : 9 X ; 20 : AO : 91 : A9 , AO : 9 1 : 20 AO 9 1 20 AO 9 1 20 48 49 B6 IE B9 IF 79 1 48 7F 02 48 00 3 48 85 4 48 8B 05 48 9 1 40 40 40 40 40 54 55 56 57 58 59 60 6 1 62 63 64 65 6 6 67 68 69 70 7 i 72 7 3 74 75 76 77 78 79 STY STA LDA STA LDA STA JSR ASL ASL ASL ASL LDY STA JSR LDY STA LDA LDY STA JSR LDY STA JSR LDY STA JSR I OB IOB+1 TXTPTR TPSAV TXTPTR+1 TPSAV + 1 GETSL% A A A A #IBSLGT < IOB) , Y GETDR<* # IBDRVN ( IOB ) , Y #«00 #IBVOL < IOB ) , Y GETTR% # IBTRK < IOB ) , Y GETSE% § IBSECT ( iob) ; Y GETBUV* \ SAVE IT ;SAVE TXTPTR ;G£T SL% (SLOT) ;TIMES 16 ;GET DR* (DRIVE) ; VOLUME-0 ;GET TR% (TRACK) GET SEVi (SECTOR) GET BU% ( BUFFER) TM TRS-80'S and Hewlett- Packards Best Discounts Possible WE PAY SHIPPING in the 48 continental states on prepaid orders of $100.00 or more. NO TAXES are collected on out-of-state shipments. WE ACCEPT Visa, MasterCard and American Express, or you can save additional money by paying cash. TOLL FREE ORDER NUMBER 800/531-7466 Pan American Electronics 1117 Conway • Dept. 16 Mission, Texas 78572 Phone 512/581-2766 Telex Number 767339 FORT WORTH BRANCH 2912 N. Main Ft. Worth, Texas 76106 Phone 817/625-6333 Telex Number 794836 TM — Trademark of Tandy Corporation A MITSUBISHI FLEXIBLE DISK DRIVE SETTING NEW STANDARDS FOR RELIABILITY AND DURABILITY • FULLY IBM AND SHUGART SA85QR COMPATIBLE • DOUBLE-SIDED, DOUBLE-DENSITY • 1.6 MBYTE/DISK • SOFTOUCH™ PROPRIETARY HEAD LOAD MECHANISM • 3 MS TRACK-TO-TRACK ACCESS TIME • HIGH QUALITY, ALL FERRITE MnZn HEADS • PRECISION BUILT/MODULAR CONSTRUCTION • 6 MONTH WARRANTY $525.00 Available from stock. Terms: cash, check, money orders, VISA, MasterCharge. Tax: 6% if California resi- dent. 'Price subject to change without notice. $ 1333 Lawrence Expressway, Suite 408 Santa Clara, California 95051 (408) 247-3450/TWX 910-338-7442 AUTHORIZED SALES AND SERVICE AGENT FOR INFORMATION CONTACT HOLLY SAUER OEM INQUIRIES INVITED 460 April 1982 © BYTE Publications Inc Circle 325 on inquiry card. Circle 292 on inquiry card. listing 3 continued: 4038 A0 08 80 LDY # IBBUFF 403A 91 48 8 1 STA < IOB > , Y ; LOW BYTE 403C AO 00 82 LDY #$00 4 03E Bi 83 83 LDA ( VARPNT) j Y ^040 AO 09 84 LDY # IBBUFF+1 4042 91 48 85 STA ( IOB > , Y HI GH BYTE 4044 20 9 7 40 86 JSR GETCM% GET CM% (COMMAND) 4047 FO 27 87 BEQ RETURN NULL COMMAND 4 049 AO OC 88 LDY # IBCMD 404B 9 1 48 89 STA < IOB) , Y 404D 20 9D 40 90 JSR GETER% GET ER% POINTER 4050 20 E3 03 9 i JSR GETIOB 4053 20 D9 03 92 JSR RWTS 4056 AO OD 93 LDY # IBSTAT 4058 81 43 94 LDA ( IOB) , Y ERROR CODE 405A BO 02 95 BCS ERROR ,RVTS SETS C BIT ON ER 405C A? 00 96 LDA §•00 ER%»0 IF C BIT CLEAR 405E : AO 01 97 ERROR LDY M-0* 4060 9 1 83 98 STA ( VARFNT) j Y RETURN IBSTSAT IN ER% 4062 Bl 48 99 LDA ( IOB > , Y Y-IBSLOT 4064 AO OF 100 LDY #IOBFSN 4066 9 1 48 10 1 STA < IOB) , Y ; UPDATE SLOT 4068 AO 02 102 LDY # IBDRVN 406& Bl 48 103 LDA ( IOB ) , Y 406C AO 1 i 04 LDY # IOBFDN 406E : 9 1 48 105 STA ( IOB) , Y UPDATE DRIVE Listing 3 continued on page 462 @ Buckeye DESK TOP ENCLOSURES ASK ABOUT OUR NEW BRACKET MOUNTING SYSTEM FOR DWC CASES DWC-1-0850 7 $54,70 DWC-1-1133 60.60 DWC-1-1600 68.80 BKS-2-0850 $41.50 BKS-2-1133 44.80 BKS-2-1600 48.30 Send check for case in width desired. Call or write for detailed literature The Buckeye Stamping Co. 555 Marion Rd., Columbus, OH 43207 614/445-8433 MICROCOMPUTER IDEA B00K& CATALOG. I One-Stop Strapping. More than 1000 microcomputer accessories and supplies - from diskettes and line- printer paper to connectors and cables - for Apple, Alan. Northstar, TRS-SOs and many others Loaded with ideas for extra convenience and efficiency I Easy Ordering. By mail, phone, or TWX Friendly, helpful, expert assistance I Fast Delivery. Your order shipped in 24 hours from the Inmoc Center nearest you Overnight emergency shipments also available I Risk- Free Trial. Try any product for 45 days If not satisfied, return for full refund I Guaranteed Quality. Field-tested for precision performance and compatibil- ity. Backed by warranties ranging up to 10 years - and some with Lifetime Guarantees. Please RUSH my copy of the Microcomputer Idea Book & Catalog. Name Title Company Phone Address City SEND TODAY FOR YOUR FREE MICROCOMPUTER IDEA BOOK & CATALOG OR PHONE (408) 727-1970. Zip mmao Catalog Dept., 2465 Augustine Dr., Santa Clara, CA 95051. Circle 61 on inquiry card. Circle 206 on inquiry card. April 1982 © BYTE Publications Inc 461 Listing 3 continued: 4070;A5 IE 106 RETURN LDA TFSAV ; RESTORE TXTPTR 40 7 a ; 85 B8 107 STA TXTPTR «J074 : A5 1 F 108 LDA TPSAV+ L 4 076:85 B* 109 STA TXTPTR- ► 1 4 78:60 110 RTS ;TO APPLESOFT 4079: 1 i i * 4 7 9: 112 * Find Applesoft variables: 4 7 9.: 1 1 3 * 4079:20 A3 4 114 GETSL* JSR VARGET 407C : 53 4C 25 115 ASC : SLO- 4 7F : 20 A3 40 116 GETDR* JSR VAK GET 4082 : 44 52 25 117 ASC ' DR /. 1 4085:20 A3 40 118 GETTR% JSR VARGET 4088:54 52 25 119 ASC * TR% s 408B:20 A3 40 120 GETSE% JSR VARGET 4 08E : 53 45 25 121 ASC 1 SE% 1 4091:20 A3 40 122 G£TBU% JSR VARGET 409442 55 25 123 ASC 1 BU%' 40 97:20 A3 40 124 GETCM% JSR VARGET 409A 43 4D 25 125 ASC ' CM% f 409D:20 A3 40 126 GETER^ JSR VARGET 4 0A0 45 5 2 2 5 127 ASC ' ER%' r TERMINALS FROM TRANSNET' THE ENCRYPTOR™ DATA SECURITY * S-lOO COMPUTERS. IEEE-696 DESIGN. * CP/M* SOFTWARE ON 8 INCH SINGLE DENSITY DISKETTE AVAILABLE. * NATIONAL BUREAU OF STANDARDS ENCRYPTION ALGORITHM. * HIGH SPEED A.M.D. 9518 DATA CIPHERING PROCESSOR. * 1.3 megabytes per second throughput. * 3 encryptiqn/decrypti gtv formats. * over 72 quadrillion 56 bit master keys. * plug selectable i/o port addresses and interrupts. * gold plated fingers, card ejectors and solder mask. * assembled, burneo-in and tested. * 1 year limited warranty. * $425.00 single quantity. * it cash discount for money orders and c.o.d.'s. * mastercard and visa credit cards accepted. * shipping charges added to all grders. * 63 sales tax added to pennsylvania destinations. * prices and specifications subject change without notice. * dcaler and u.e.m. inquires invited. PURCHASE PUN -12-24 MONTH FULL OWNERSHIP PLAN • 36 MONTH LEASf PURCHASE PEH M0WTH DESCRIPTION PRICE 12 MOS 24 MOS PLAN 3BM0S S 40 36 40 83 75 61 43 119 63 72 86 58 93 25 86 102 61 80 22 24 42 72 61 36 116 31 39 104 119 43 80 49 61 27 32 55 74 DEC uuo utbwnier u 51 .uao > iuo a 30 LA34 DECwriter IV 995 95 53 LA34 DECwriter IV Forms Ctrl. .. 1,095 105 58 LA120 DECwriter III KSR 2,295 220 122 LA120 DECwriter III RO 2,095 200 112 VT100 CRT DECscope 1,695 162 90 VT1 01 CRT DECscope ... . 1,195 115 67 VT125 CRT Graphics 3,295 315 185 VT131 CRT DECscope 1,745 167 98 VT132 CRT DECscope 1 ,995 190 106 VT18XAC Personal Computer Option 2,395 230 128 TEXAS INSTRUMENTS T1745 Portable Terminal 1 ,595 153 85 TI765 Bubble Memory Terminal . 2,595 249 138 Tl Insight 10 Terminal 695 67 37 TI785 Portable KSR, 120 CPS. . . 2,395 230 128 TI787 Portable KSR, 120 CPS .. . 2,845 273 152 TI810 RO Printer 1 ,695 162 90 TI820 KSR Printer 2,195 211 117 LEAR SIEGLER ADM3A CRT Terminal 595 57 34 ADM5 CRT Terminal 645 62 36 ADM32 CRT Terminal 1 ,165 112 65 ADM42 CRT Terminal 1,995 190 106 EXCEL 12 CRT Terminal 1 ,695 162 90 EXCEL 42 Smart Buffered CRT.. 995 96 54 COLORSCAN 10 Color CRT 3,195 307 171 DATAMEDIA TELEVIDEO 925 CRT Terminal 850 82 46 950 CRT Terminal 1,075 103 57 NEC SPINWRITER Letter Quality, 7715 RO 2,895 278 154 Letter Quality, 7725 KSR 3,295 316 175 GENERAL ELECTRIC 2030 KSR Printer 30 CPS 1.195 115 67 2120 KSR Printer 120 CPS 2,195 211 117 Executive 80 20 1,345 127 75 HAZELTINE Executive 80 30 1.695 162 90 MX-80 FT Printer 745 Tl 42 trdun MX-1 00 Printer 895 86 48 TIMEPLEX EQ400 4 Channel Stat Mux .... . 1 ,525 147 82 E0800 8 Channel Stat Mux 2,050 197 110 FULL OWNERSHIP AFTER 12 OR 24 MONTHS • 10% PURCHASE OPTION AFTER 36 MONTHS MICROCOMPUTERS APPLE • COMMODORE • HP85 • DEC LS1 11 * TELEPHONE 2 15-865-1222 * MONDAY-FRIDAY, 8AM-5PM, EASTERN TIME * LEHIGH VALLEY LOGIC, INCORPORATED * 25U3 NORTH COURT * litFHLEHEM, PENNSYLVANIA 18017 U.S.A. ACCESSORIES AND PERIPHERAL EQUIPMENT ACOUSTIC COUPLERS • MODEMS ■ THERMAL PAPER • RIBBONS • INTERFACE MODULES • FLOPPY DISK UNITS IU / RA NSNE T corporation ■LAJ 1945 ROUTE 22 • UNION, N.J. 07083 • (201) 688-7800 TWX 710-985-5485 800-526-4965 OUTSIDE N.J. J * CP/M IS A REGISTERED TRADE MARK OF DIGITAL RESEARCH, INC. 462 April 1982 © BYTE Publications Lnc Circle 418 on inquiry card. Circle 234 on inquiry card. Listing 3 continued: 40A3 ; 40A3 : 40A3: 40A3 : 40A3 : 4 A 3 : 40A3: 4 A 3 : 6 8 40A4 85 Bfe 40A6 : 68 40A? : 85 B9 40A? : 40A9 : £6 B8 40AB DO 02 4 0ADE6 B9 40AF 20 E3 4 B 2 ; A 1 40B4 :B1 83 40B6 : 40B6 : 60 DF i 28 1 2? i 30 1 31 132 1 33 1 3 4 1 35 1 36 1 37 1 38 1 3 9 1 4 1 4 1 1 42 1 43 1 44 145 1 46 1 47 * * A * * VARGET PX-A STA FLA STA * I no r emen t INC VARGET: On entry to FTRGET, TXTFTR points to first character of the variable name. On exit, the address of the variable's value is in VARPNT and Y r A. Fop return stack and store variable pointer in TXTFTR. TXTFTR TXTFTR -t-1 pointer to TXTFTR VAR1 TXTFTR + 1 FTRGET it Q.l < VARFNT) , Y is to fee ond first character in ASC string VAR 1 * Note BNE INC JSR LDY LDA return RTS most recent caller *** SUCCESSFUL ASSEMBLY; NO ERRORS MODEM HEADQUARTERS Connect any computer or terminal to the phone tines! 1200 Baud — 120 Characters per Second Penril 300/1200 $739 Bell 212A identical. Full duplex, RS232. 1200 and 300 Baud. Originate/auto-answer. Phone connection via RJ11C standard phone jack. One year warranty. Self-test. Fits under phone. 300/1200 Auto-Dialer $225 Allows any computer to automatically dial out through the Penril 300/1200. 300 Baud — 30 Characters per Second Phone Link Acoustic Modem $129 Originate and Answer. Half/Full duplex. RS232. Operates with any standard telephone. Indicators for On, Carrier, Self-test, Send Data, Receive Data. One year warranty. Micro-link $179 Originate/Auto-Answer, Half/Full duplex. RS232. Phone connection via RJ11C standard phone jack. Indicators for On, Carrier Detect, Self-test, Send Data, Receive Data. Two year warranty. Fits under phone. ADDS Viewpoint CRT $529 GE2120 Printing Terminal $1,799 150 CPS. 300/1200 Baud. GE2030 Printing Terminal $999 60 CPS. 300/1200 Baud. Aft equipment is in stock. Your satisfaction guaranteed. Any product may be returned for futi credit. Write or cati for tuli product information. m U.S. ROBOTICS inc. 203N.WABASH suite me CHICAGO, ILL B060I DUAL THERMOMETER COMPL FTWARE » Display temperature, maximum, minimum and difference. • Sound alarm for over/ under temperature. • Store data on disk or printer automatically. • Display time with on- board timer. • Up to 7 boards with 1 4 probes in one Apple*. • -55 Ctol25 Crange, 0.4° accuracy over most of range. • Requires 48K Apple* with Applesoft* and disk. $260.00 Strawberry Tiree Computers ifyour dealer doesn't w cascade Drive ^p-v have it, call or write us at Sunnyvale, Ca. 94087 ff\ \ -j--«. a (408) 736-3083 I V t J aepi. A xbcV' *TM of Apple Computer. Inc. Circle 421 on inquiry card. Circle 386 on inquiry card. April 1982 © BYTE Publications Inc 463 A Simple Multiprocessor Implementation A simple connection can be the start of a multiprocessing, multitasking system. Have you been looking for an easy way to simultaneously operate more than one computer? If you have, your search is at an end. In this article, I describe a method to control two or more computers connected by serial data lines. Even if the computers are performing completely unrelated tasks, they can still be controlled from a single terminal. For example, one machine might run a BASIC program, while the other controls your home-security system. Or one could print a data file on a hard-copy device, while the op- erator updates the same file on the other machine. Another possibility is the job per- formed by some very large comput- ers — splitting a single task into seg- ments and processing the segments separately but simultaneously. This provides good news and bad news. The good news is an impressive re- duction in the time needed to com- plete the overall task. The bad news is the complexity of the software re- quired to accomplish this! For several years, some friends and I kicked around the idea of intercon- necting computers. Many gallons of coffee and plenty of discussion yielded many possibilities. We wrote some extensive software to allow the exchanging of programs and data via John Harrington 3840 West Clarendon Phoenix, AZ 85019 modems and telephone lines, and played around with multiple-pro- cessor printer spoolers, but never did implement multiprocessing. However, I was given an excellent opportunity to experiment when I up- graded my SwTPC 6800-based dual- disk-drive machine with a Motorola 6809 processor. This was accom- plished by making some minor hard- ware changes and plugging in a new In certain situations, assigning more than one task to a single processor noticeably increases overall execution time. 6809 processor card. The old 6800 card was plugged into another motherboard, with a homemade power supply. A friend had built a wooden cabinet for his SwTPC com- puter; his original cabinet soon held my second computer. Since my bank- roll was limited, extra memory and input /output hardware were added sparingly. Some swapping got me a Shugart Associates SA-400 5 V* -inch floppy-disk drive. Before long, I was the proud owner of two almost iden- tical disk-based microsystems, one running a 6800, the other, a 6809. Both machines run FLEX, Techni- cal Systems Consultants' (POB 2570, West Lafayette, IN 47906) excellent DOS (disk operating system). FLEX contains a built-in interrupt-driven background (i.e., invisible to, and not interactive with, the user) printer spooler, allowing low-priority disk- file printing while the main user task is running in foreground. This is called "limited multitasking/' But if two things are happening at once on one computer, isn't that just as good as having two computers? No, not quite. Spooling is a beautiful feature I use often, but it has a few drawbacks. First, only two tasks are permitted, one of which must be the printing of the contents of a disk file. Second, because the two tasks are swapped under interrupt control, background printing slows or stops while disk ac- cesses, or any operations that mask interrupts, are being performed. This is particularly noticeable when you are using fast printers. In fact, any single-processor multi- tasking scheme has an inherent limitation. The available processor time is split between the tasks. As a result, no task can run as fast as it would alone. On I/O- (input/output) intensive tasks, where much time is spent waiting on I/O devices or oper- 464 April 1982 © BYTE Publications Inc ator input, the effects of this time division may be unnoticeable. On the other hand, if the tasks rarely have to wait on I/O, execution time may slow down in almost inverse propor- tion to the number of tasks. These problems can be avoided by multiprocessing. Since I now had two nearly identical machines, all excuses for not developing a multiprocessing system were gone. Several ap- proaches to putting the system together were considered. The easiest one is to designate one machine as the primary unit, and let it control the other as a secondary machine. All control for the secondary machine has to pass through the primary. Lit- tle extra hardware is required, and the software is simple. Another scheme is to use multiport memory, a special block of memory set up so that either machine may ad- dress it. To pass data or instructions between machines, the data are writ- ten by one processor to this memory and read by the other. Although very fast, this approach requires special hardware and some complex soft- ware. Similar drawbacks would oc- cur if we used DMA (direct memory access — the transmission of data directly between the memory of a Shared-memory, direct-memory-access, and shared-bus multiprocessing systems involve both complex hardware and software. computer and a peripheral device, which might be the other processor) to pass data. Another approach is to design a small dedicated controller, such as a single-chip microprocessor with a program in ROM (read-only mem- ory), to control the larger machines. The terminal connects to the con- troller, which in turn controls the other machines via serial data ports. Several other possibilities exist, in- cluding using a shared bus, where two or more processors communicate directly with memory and I/O via read and write instructions, as with the Intel 8086, Zilog Z8000, and Motorola 68000 16-bit microproces- sors. The method chosen for my first try was the simplest — the primary /sec- ondary concept. The machines do not have to be identical, or even similar. Both only need serial ports that can be interconnected, as in figure 1. The ones shown here are serial RS-232C ports. A serial port on the primary machine (designated machine 1) is plugged into the control port of the secondary machine (designated ma- chine 2) where a user terminal would be connected in a single-user system. Any data or commands output from machine 1 through this port are obeyed by machine 2 as though they came directly from the control ter- BROAD BAND MICROWAVE RECEIVER SYSTEM 1.8GHZ to 2.4 GHZ only $295.00 With built-in-converter to channel 2, 3, or 4 of any standard TV set. 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HARRINGTON CD03 WARMS EQU $CD03 E004 PORTI EQU $E004 E008 P0RT2 EQU $E008 CD18 PUTCHR EQU $CDI8 CC2B M EMEND EQU $CC2B CD24 PCRLF EQU $CD24 CDIE PSTRNG EQU $CDIE CCI2 UCTADD EQU $CC12 CI 00 ORG SC100 CI 00 20 01 START BRA MACH2 CI02 01 FCB 1 CI 03 BD CD24 MACH2 JSR PCRLF CI 06 86 03 LDA #3 C108 B7 E008 STA P0RT2 C10B 86 II LDA #$l 1 CIOD B7 E008 STA P0RT2 CI 10 FC CC2B LDD MEMEND CI 13 FD CI 3D STD ORIGME C.l 16 83 00D5 SUBD #ENDPGM- CI 19 FD CC2B STD MEMEND CI IC IF 01 TFR D,X CI 1 E 30 01 LEAX ia CI 20 34 10 PSHS X CI 22 108E C210 LDY #ENDPGM C126 34 20 PSHS Y CI28 108E CI3B LDY #MACH20 CI2C A6 AO MOVE LDA ♦ Y+ C12E A7 80 STA .X+ CI30 I0AC E4 CMPY •s CI 33 20 F7 BNE MOVE C135 32 62 LEAS 2,S CI37 35 10 PULS X CI 39 6E 84 JMP • X FLEX 9 WARMSTART CONTROL PORT ADDRESS PORT TALKING TO SECOND MACHINE OUTPUT CHARACTER TO CONTROL PORT "END OF MEMORY" STORAGE TO CONTROL PORT AND STRING TO CONTROL PORT USER COMMAND TABLE ADDRESS BRANCH OVER VERSION VERSION I MASTER RESET FOR ACIA PORT 8 BITS, NO PARITY, 2 STOP BITS PORT IS NOW INITIALIZED PRESENT END OF MEMORY SAVE IT FOR LATER ■MACH2.0 SUBTRACT LENGTH OF PART TO BE MOVED SET MEM.ORY END JUST BELOW OUR PROGRAM MEMEND GOES INTO X NOW X HAS NEW STARTING ADDRESS SAVE IT LAST BYTE TO BE MOVED SAVE ITS ADDRESS FIRST BYTE TO BE MOVED GET A BYTE OF THIS PROGRAM AND MOVE IT FINISHED? NOT YET FIX STACK GET NEW STARTING ADDRESS AND GO THERE * THE REST OF THIS PROGRAM GETS RELOCATED TO A * NEW SPOT JUST UNDER TOP OF USER MEMORY SPACE. * THE CODE IS POSITION-INDEPENDENT AND WILL RUN * ANYWHERE. PART OF THE CODE MOVED IS AN EXTENSION * TO THE FLEX COMMAND TABLE (COMTBL). 468 April 1982 © BYTE Publications Inc Listing 1 con tinned: C13B 20 02 MACH20 BRA MACH21 BRANCH AROUND TEMP STORAGE CI 3D 0000 ORIGME FDB ORIGINAL TOP OF MEMORY ADDRESS CI3F 30 8D 0013 MACH21 LEAX MACH22,PCR GET NEW ADDRESSES FOR ROUTINES CI 43 AF 8D OOBC STX ADDRI , PCR AND PUT IN COMMAND TABLE CI 47 30 8D 0050 LEAX RESTORE, PCR CI4B AF 8D OOBE STX ADDR2 f PCR CI4F 30 8D OOAA LEAX COMTBL, PCR POINT TO COMMAND TABLE C153 BF CCI2 STX UCTADD TELL FLEX WHERE IT IS NOW CI56 30 8D 004F MACH22 LEAX MSG f PCR "YOU ARE NOW CONTROLLING MACHINE TWO" CI 5A BD CD IE JSR PSTRNG CI bD BD CD24 JSR PCRLF C160 8E E004 MACH23 LDX #P0RT1 POINT TO CONTROL PORT CI 63 8D 22 BSR CHECK ANY KEYBOARD INPUT? CI65 24 12 BCC MACH2 5 NOPE CI67 8D 22 BSR INPORT YES- GET THE CHARACTER C109 31 Id CMPA #$18 CONTROL-X? CI6B 26 OA BNE MACH24 NOPE CldD 30 8D 005F LEAX MSG2 f PCR "YOU ARE NOW CONTROLLING MACHINE ONE (6809)" CI 71 BD CD IE JSR PSTRNG C! 74 7E CD03 JWARMS JMP WARMS BACK TO FLEX CI 77 8D I 7 MACH24 BSR 0P0RT2 SEND TO SECOND MACHINE C179 BE E008 MACH25 LDX #P0RT2 POINT TO SECOND MACHINE CI 7C 8D 09 BSR CHECK IS IT TALKING TO US? CI7E 24 EO BCC MACH23 NO, LOOP CI 80 8D 09 BSR INPORT YES, GET THE CHARACTER CI82 BD CDI8 JSR PUTCHR PRINT ON CRT CI 85 20 D9 BRA MACH23 AND LOOP FOR MORE • CHECK PORT FOR INPUT- 1 ENTER WITH PORT ADDRESS • IN X REGISTER CI 87 A6 84 CHECK LDA .X GET STATUS BYTE CI 89 47 ASRA SHIFT STATUS BIT INTO CARRY CI8A 39 RTS CARRY SET INDICATES CHARACTER WAITING * INPUT CHARACTER FROM A PORT (ENTER WITH PORT ADDRESS IN X) C18B A6 01 IMPORT LDA i,x GET THE CHARACTER C18D 34 7F ANDA #$7F STRIP PARITY BIT, IF ANY CI8F 39 RTS * SEND CHARACTER TO PORT TWO (SECOND MACHINE) CI 90 F6 E008 0P0RT2 LDB P0RT2 GET STATUS BYTE CI 93 57 ASRB SHIFT READY BIT INTO CARRY CI 94 57 ASRB CI 95 24 F9 BCC 0P0RT2 LOOP UNTIL READY Ci 97 B7 E009 STA P0RT2+1 SEND THE CHARACTER CI9A 39 RTS * RESTORE MACHINE TO ORIGINAL CONDITION CI 9B 8E 0000 RESTORE LDX #0 CI 9E BF CCI2 STX UCTADD CLEAR EXTENSION TO COMMAND TABLE C1A1 AE 8C 99 LDX ORIGME f PCR GET ORIGINAL MEMORY END ADDRESS CIA4 BF CC2B STX MEMEND PLUG IT BACK IN CI A7 20 CB BRA JWARMS AND EXIT • STRINGS CIA9 20 2D 59 4F MSG FCC / -YOU ARE NOW CONTROLLING MACHINE TWO-/ ,4 CI DO 20 2D 59 4F MSG2 FCC / -YOU ARE NOW CONTROLLING MACHINE ONE <6809)/ f 4 • COMMAND TABLE CIFD 4D 41 43 48 COMTBL FCC /MACH2/ f C203 CI 56 ADDR1 FDB MACH22 C205 52 45 53 54 FCC /RESTORE/ ♦ April 1982 © BYTE Publications Inc 469 Listing 1 continued: C20D C19B C20F 00 C2I0 00 ERRC)R(S) DETECTED ADDR2 FDB FCB ENDPGM FCB END RESTORE START SYMBOL TABLE* ADDR1 C203 ADDR2 C20D CHECK CI 87 COMTBL C1FD ENDPGM C2 10 INPORT C18B JWARMS CI 74 MACH2 C103 MACH20 CI3B MACH2 1 CI3F MACH22 CI 56 MACH23 CI 60 MACH24 CI 77 MACH25 CI79 MEMEND CC2B MOVE CI2C MSG C1A9 MSG2 CI DO 0P0RT2 CI 90 ORIGME CI 3D PCRLF CD24 PORT! E004 P0RT2 E008 PSTRNG CDIE PUTCHR CD18 RESTOH C! 9B START CI 00 UCTADD CCI2 WARMS CD03 Text continued from page 467: program, to protect it. This address is checked by most software, which will not use memory above it, making the program fairly safe from being clob- bered. Now that the program is in a safe place, you transfer control to it, and it executes. The flowchart (figure 3) shows how it works. All communi- cation with machine 2 is routed through the program until a Control- X is entered from the keyboard, at which time it jumps to the DOS, put- ting you back in control of machine 1. Executing the program again sends your communication to machine 2, and so on. Now comes the tricky part. FLEX allows its command table, the look- up table of memory-resident pro- grams and routines that appear as DOS commands to the user, to be ex- tended to include any number of new Music and Art Cross Paths at the Computer DIGITAL HARMONY On the Complementarity of Music and Visual Art By John Whitney BYTE Books is pleased to offer Digital Harmony, a major new work by John Whitney. Digital Harmony lays the foundation for the new field of audiovisual art made possi- ble by microcomputers. Whitney, whose film art has been an influence on technolo- gical arts and cinematic special effects from STAR WARS to 2001: A SPACE ODYSSEY, explores the special union of music and computer graphics. Colorful illustrations as well as the program listings that generated them are included. The descriptions are sufficient for any composer or computer experimenter to transform the small computer into an ideal in- strument for creating composi- tions in aural and visual art. BUMS Please send me: copies of DIGITAL HARMONY $21.95 Add 75C per book to cover postage and handling. Please remit in U.S. funds or draw on a U.S. Bank. [ j Check enclosed in the amount of $. , — Bill VISA : Bill MasterCard Acct No. , Expires Name . ,.„ Title _ Company Street City State/Prov. O Call our toil-Free Number 800-258-5420 70 Main St. Peterborough, NH 03458 ■ & commands. The advantage of mem- ory-resident programs is that they don't have to be loaded from disk each time they are used — just type in the name of the program and it's run- ning. FLEX does the difficult part. You just have to create the new command-table extension and tell FLEX where it is. This is done by stuffing the address of the table in a special memory location. Then, whenever you type in a command, FLEX looks at its table, then your table, before looking on the disk for the command. This is the way it works: after power-up, the first time you type "MACH2" the program is loaded from disk and run. Subsequent calls to MACH2 are instantaneous, since the program is already in memory and the addition to the command table points to it. This feature saves much time and disk wear in a long session. The added command table is physically located at the end of the program. Remember, this is a pro- tected area of memory, not likely to get written over. Two commands are in the table: "MACH2", which con- nects the terminal to machine 2, as described earlier, and ''RESTORE", which turns off the multiprocessing. That is, it restores machine 1 to its original configuration by disabling the new command table and putting the top-of-memory pointer back to its original value. RESTORE was used mainly during program development and debug- ging. It is not particularly useful now. No provisions were made in the pro- gram for passing data files between 470 April 1982 © BYTE Publications Inc Circle 68 on inquiry card. I BEGIN J PRINT "YOU ARE NOW CONTROLLING MACHINE TWO" ON TERMINAL CHARACTER I READY AT | KEYBOARD PORT YES nS IT A\^ YES ^CONTROL-X^- ? SEND CHARACTER TO SECOND MACHINE NO NO CHARACTER ■ — | READY FROM MACHINE TWO YES PRINT THE CHARACTER ON THE TERMINAL PRINT YOU ARE NOW CONTROLLING MACHINE ONE" ON TERMINAL Figure 3: Flowchart of the algorithm used in the communications and control program given in listing 1. machines, just commands. Presently, I move text or data files between machines by swapping disks between drives. If you are running FLEX on a 6809-based computer, you can use this software as is. If not, the algo- rithm represented by the flowchart of figure 3 can easily be written in almost any language on any com- puter. It could even be written in BASIC, if you have latent masoch- istic tendencies. The extra command table and the self-relocation features are not required, but are handy. You might even extend the algo- rithm to control a dozen or more machines. That'll keep you out of trouble for a year or two — trying to dream up a dozen things you need to do simultaneously. Presently, data transfer is limited to a rate of 9600 bps, the maximum speed available on the serial ports without modification. This just isn't fast enough for some things I have in mind, so my next major project will be dual-port memory for very fast transfer of data between machines. But I think if you try the present scheme, you'll like the results. ■ HIS CONTRIBUTIONS WERE AE POSSIBLE BY YOURS. v when you give to the United .jro College Fund, you help sup- Ft 4 1 private, tour-year colleges d graduate schools. Col teg es that could be training a black profes- onal you may need some day. Send your check to United egro College Fund. Box B. 500 E. 62nd Street. New York. MY. 002 1 . We re not asking for'a handout, just a hand. rcan do it alone. GIVE TO THE UNITED NEGRO COLLEGE FUND. A mind is a terrible thinq to waste. A public service or this nittgaitne and f he Advertising Council. April 1982 © BYTE Publications Inc 471 An Introduction to NSC Tiny BASIC The Language of the INS8073 Jim Handy National Semiconductor 2900 Semiconductor Dr. Santa Clara CA 95051 408-737-4613 National Semiconductor's new INS8073 Microinter- preter is the first single IC (integrated circuit) that can be programmed in a high-level language. Since a description of the hardware in INS8073-based systems has already appeared elsewhere (see "On-Chip Tiny BASIC Dumps Development Systems/' Electronic Design, November 22, 1980, page 235), this article will focus on the language of the new chip. Called NSC Tiny BASIC, it resembles other Tiny BASIC interpreters but has certain enhance- ments, which I'll describe in detail. (See table 1 for a sum- mary of NSC Tiny BASIC features.) Especially note- worthy are NSC Tiny BASIC features that make inter- rupts and input/ output (I/O) routines easy to handle and others that make provisions for multiprocessing. NSC Tiny BASIC offers advantages to both the inex- perienced and the experienced programmer. Using NSC Tiny BASIC, the inexperienced programmer can write comprehensive programs in much less time than equivalent assembly-language programs would require. And since NSC Tiny BASIC lets you jump back and forth About the Author At the time he wrote this article, Jim Handy was product marketing engineer for single-chip microcomputers at National Semiconductor Corporation. He is now employed by Digital Research. between machine code and BASIC, the experienced pro- grammer can write less important routines in BASIC while still using assembly-language for critical routines. Language Expressions NSC Tiny BASIC permits the use of 26 variable names: the letters A through Z. The values assigned to these variables are 16-bit signed integers. Fractions or floating- point numbers are not allowed. All numeric constants are decimal numbers except when preceded by a number sign (#), which indicates a hexadecimal number. For example, "55" would be treated as a decimal number, while "#55" would be treated as hexadecimal (equal to 85 decimal). Decimal constants must be in the range of —32767 to +32767. Relational operators are the standard BASIC symbols ( = equal to; > greater than; < less than; < = less than or equal to; > = greater than or equal to; < > not equal to). The relational operators return either a (FALSE) or — 1 (TRUE) as a result. Note that > < is an illegal operator. Standard arithmetic operators are provided for the four basic arithmetic functions ( + addition; — subtrac- tion; / division; * multiplication). The arithmetic is stan- dard 16-bit two's-complement arithmetic. Fractional quo- tients are truncated at the right, not rounded, and re- mainders are dropped; therefore, both 16/3 and 17/3 472 April 1982 © BYTE Publications Inc give 5 as a result. As usual, division by zero is not permit- ted; it will result in an error break. NSC Tiny BASIC follows the usual algebraic rules for order in evaluating expressions. Parentheses control the order of evaluation, and you should use them liberally. They insure clarity in complicated expressions. NSC Tiny BASIC provides logical operators AND, OR, and NOT. These perform bitwise logical operations on their 16-bit arguments and produce 16-bit results. The AND and OR operators are called binary operators because they perform an operation on two arguments (or operands). Here's an example of the use of AND, with the binary interpretation shown at right: >LIST 10A = 75 20 B = 99 30 C = A AND B 40 PRINT C >RUN 67 A = 0000 0000 0100 1011 B = 0000 0000 0110 0011 C = 0000 0000 0100 0011 The following program shows how the logical AND can be used with other relational operators: >LIST 10 INPUT A 20 INPUT B 30 IF (A>50) AND (B>50) THEN GO TO 60 40 PRINT 'ONE OR BOTH ARE SMALL" 50 GO TO 10 60 PRINT "BOTH ARE BIG" 70 GO TO 10 If we run the program, console output will look like this: >RUN 7 51 ? 52 BOTH ARE BIG 7 51 Expressions Variable Names A — Z Decimal constants in the range -32767 to +32767 Hexadecimal numbers (preceded by a "#") Operators Relational Operators > < > = < > Arithmetic Operators + / * Logical Operators AND OR NOT The Indirect Operator Accesses absolute memory locations one byte at a time; e.g., LET X= @6800 assigns value at address 6800 to X. Yields absolute value of remainder from division of a by b Generates pseudorandom integer in range from a through b, inclusive Represents 8-bit value of the status register Yields address of first byte above the pro- gram in the current page of RAM Increments a memory location Decrements a memory location Functions MOD (a,b) RND(a.b) STAT TOP INC DEC Statements Input/Output Statements INPUT Inputs one or more expressions or numbers, separated by commas (or spaces) Table 1: A summary of NSC Tiny BASIC features. INPUTS A PRINT Inputs a string to successive memory loca- tions starting at location A Outputs information from program; gives decimal numbers and quoted strings PRINT $ B Prints string beginning at address B up to next carriage rturn Assignment Statements LET Sets a variable, memory location, string variable or the status register to value entered Program-Control Statements GOTO GOSUB RETURN IF/THEN DO/UNTIL FOR/NEXT STEP LINK ON STOP CO NT DELAY CLEAR Commands NEW RUN LIST Branches to line number Calls subroutine at line number Returns control from subroutine to line following GOSUB statement Shifts program control based on result of logical test Causes repetition of enclosed statements until specified condition is met Causes repetition for specified number of times Sets size of increment in iterations of FOR/NEXT statements Transfers control to a machine-language routine at a specified address Helps process interrupts; "ON interrupt-#1, 200" transfers control to GOSUB statement at line 200 when specified interrupt occurs. Causes program to stop and prints current line number, then returns to edit mode Resumes execution of program stopped by STOP Delays execution for specified number of time units up to maximum of 1040 milliseconds Initializes all variables to 0, disables inter- rupts, enables BREAK capability, resets all stacks Establishes a new start-of-program address Runs the current program Lists the current program April 1982 © BYTE Publications Inc 473 7 49 ONE OR BOTH ARE SMALL 7 49 7 49 ONE OR BOTH ARE SMALL 7~C STOP AT 10 > The following similar program shows the use of a logical OR with other relational operators: >LIST 10 INPUT A 20 INPUT B 30 IF (A>50) OR (B>50) THEN GO TO 60 40 PRINT "BOTH ARE SMALL" 50 GO TO 10 60 PRINT "ONE OR BOTH ARE BIG" 70 GO TO 10 Here's a sample run: >RUN 7 51 7 52 ONE OR BOTH ARE BIG Reliable Business Software DATASMITH software requires no previous computer experience, so it can be used effectively by your present office staff. The menu-driven systems feature extensive error detection and correction facilities, so they are "friendly" to the user. • GENERAL LEDGER. Everything you need to keep the books. Features easy-to-use data entry and error correction, trial balance, fast post, and a vari- ety of comprehensive reports. Automatic error detection keeps the books in balance. Writes checks and makes journal entries in one operation. • PAYROLL. A very flexible system that adapts to a wide variety of needs. Features Federal, state, and local tax calculations, El credit, and special pay and deduction amounts. Prints all necessary reports, paychecks, and W-2 forms. • DATA MANAGER. A powerful generalized data management system that iets you define, enter, up- date, sort, select, and print reports from a database of your own design. Applicable to almost any job where records must be kept, this system can replace literally hundreds of programs. Put your computer to work with these sophisticated systems now. Programs are available for 48K or larger two-disk systems in your choice of code for Microsoft BASIC-80® under CP/M* or Micropolis® BASIC. Write or call for complete details. Customized systems also available. DflTflSNJTH Box 8036, Shawnee Mission, KS 66208, (913) 381-9118 ? 51 7 49 ONE OR BOTH ARE BIG 7 49 7 49 BOTH ARE SMALL 7 A C STOP AT 10 > The third logical operator (NOT) is unary; i.e., it per- forms an operation on only one argument. An example follows, again showing the binary interpretation at right: >LIST 10 A = 11 A = 0000 0000 0000 1011 = 11 10 20 B - NOT A 30 PRINT B B = 1111 1111 1111 0100 = -12 >RUN 10 -12 Tiny BASIC Functions NSC Tiny BASIC offers several functions for use in arithmetic expressions. For example, the MOD (or modulo) function returns the absolute value of the re- mainder from the division a/b, where a and b are ar- bitrary expressions. If the value of b is zero, an error break will occur as in any division operation. Here's an example of the use of MOD: >LIST 10 A = 95 2 20 B = 44 44 fW 30 PRINT MOD (A,B) 88 >RUN 7 MOD (95,44) 7 The NSC Tiny BASIC random-number generator is called RND, and it returns a pseudo-random integer in the range from a through b, inclusive. For the RND func- tion to perform correctly, a should be less than b, and b — a must be less than or equal to 32767 (decimal). A typical example is: >10 PRINT RND (1,100) >RUN 27 The STAT function returns the 8-bit value of the INS8073 status register. STAT may appear on either side of an assignment statement, enabling you to modify the status register as well as read it. The carry and overflow flags of the status register are usually meaningless, because the NSC Tiny BASIC interpreter itself is continually modify- ing these flags. The interrupt-enable flag may be altered by an assignment to STAT (e.g., STAT = #FF). Loca- tions of individual flags in the status register are shown in 474 April 1982 © BYTE Publications Inc Circle 138 on inquiry card. table 2. The function of each bit in the status register is shown in table 3. Here is an example of the use of the STAT function: >LIST 10 LET A = STAT 20 PRINT A >RUN 176 The decimal number, 176, translates to 10110000 binary. Other Functions The TOP function returns the address of the first byte of RAM (random-access read/write memory) above the NSC Tiny BASIC program that is available to the user. This will be the address of the highest byte in the NSC Tiny BASIC program, plus 1. A program can use all the memory in the RAM above and including TOP as scratchpad storage. As an example: > 10 PRINT TOP >RUN 4400 4400 is the first address of unused RAM The INC and DEC functions increment or decrement a memory location X. Here are some examples: 10 LET X = 1032 20A = INC(X) 50B = DEC(X) 60 X = INC (6000) 70 Y = DEC(6000) These instructions are used for multiprocessing and are noninterruptible. This means that if two 8073s are used on the same bus, whenever one processor executes an INC (X) or DEC (X) instruction, the other processor must remain idle. These instructions are generally used for communications between processors in a multiprocessor system. Statements The INPUT statement is used to input data to an NSC Tiny BASIC program. One or more items (variables, ex- pressions, etc.), separated by commas, may be entered according to the following formats: 10 INPUT A 20 INPUT B,C When the statement at line 10 is executed, NSC Tiny BASIC prompts you with a question mark. You type in a number, which is assigned to the variable A after you press the RETURN key. NSC Tiny BASIC then prompts Most Significant Bit 7 6 5 4 3 2 1 Least Significant Bit CY/L OV SB SA F3 F2 F1 IE Table 2: A representation of the INS8073 5 through can be either read or set from status register. Bits NSC Tiny BASIC. BIT DESCRIPTION 7 CARRY/LINK (CY/L): This bit is set to 1 if a carry occurs from the most significant bit during an add, a subtract, or any instruction that alters the status register. This bit may also be set by the operations performed by the SHIFT RIGHT WITH LINK (SRL) and the ROTATE RIGHT WITH LINK (RRL) machine-language instructions. 6 OVERFLOW (OV): This bit is set if an arithmetic overflow occurs during a machine-language add or sub- tract instruction. NOTE: Bit 7 and bit 6 may be of little or no use in an NSC Tiny BASIC program. 5 SENSE BIT B (SB): Tied to an external connector pin, this bit can be used to sense external conditions. This is a "read-only" bit; it is not affected when the contents of the accumulator are copied into the status register by a STAT instruction. Sense bit B is also the second interrupt input and may be examined by use of the "ON" com- mand. 4 SENSE BIT A (SA): Like sense bit B, this bit is tied to an external connector pin and serves to sense external con- ditions. In addition, sense bit A acts as the interrupt input when the INTERRUPT ENABLE (see bit 3 of status register below) is set. This bit is also a "read-only" bit and can be examined with the "ON" command. NSC Tiny BASIC uses this bit as the serial input bit from the TTY or CRT. 3 USER FLAG 3 (F3): This bit can be set or reset as a control function for external events or for software status. It is available as an external output from the INS8073. 2 USER FLAG 2 (F2): Similar to F3. This flag is used by NSC Tiny BASIC to control the paper-tape reader relay. 1 USER FLAG 1 (F1): Similar to F3. This flag is used by NSC Tiny BASIC as the serial-output bit (with inverted data) to the TTY or CRT. NOTE: The outputs of flags 1, 2, and 3 of the status register serve as latched flags. These flags are set to the specified state when the contents of the status register are modified by an assignment to STAT, and remain in that state until the contents of the status register are modified under program control. INTERRUPT-ENABLE FLAG (IE): The processor recognizes the interrupt inputs if this flag is set. This bit can be set and reset under program control. When the interrupt-enable flag is set, NSC Tiny BASIC recognizes external interrupt requests received via the SENSE A or B inputs. When reset, this interrupt-enable flag prevents the INS8073 from recognizing interrupt requests. Table 3: A summary of the function of each bit in the INS8073 status register. April 1982 © BYTE Publications Inc 475 you with another question mark, and you type in two numbers, separated by commas. These numbers will be assigned to B and C in that order. A sample run follows: RUN 7 45 ? 237, 4455 NSC Tiny BASIC would now continue execution of the program. NSC Tiny BASIC accepts expressions as well as numbers in response to an INPUT request. For example: >LIST 10A = 10 20 INPUT B,C 30 PRINT B,C >RUN ?A + 1,A*2 11 20 The comma between the entered expressions is not man- datory and can be replaced by spaces if the second ex- pression does not start with a plus or minus sign. There must be at least as many expressions in the input list as variables in the INPUT statement. If an error occurs when NSC Tiny BASIC tries to evaluate the typed-in ex- pression, the message RETYPE is printed along with the error message, and the question mark prompt will appear again so that you can type the expressions correctly. NSC Tiny BASIC allows string input, as described in the section on string. handling, found later in this article. INPUT may not be used in the command mode. The PRINT statement is used to output information from the program. Quoted strings are displayed exactly as they appear, with the quotes removed. Numbers are printed in decimal format. A space precedes positive numbers, and a minus sign precedes negative numbers. All numbers have a trailing space. A semicolon at the end of a PRINT statement suppresses the usual carriage return and line feed with which NSC Tiny BASIC ter- minates the output. Strings stored in memory (such as those generated by a string input statement) may also be printed. A typical ex- ample: >LIST PRINT "THIS IS A STRING" 20 A = 10 30B = 20 40 PRINT "10 PLUS 20-", A + B RUN THIS IS A STRING 10 PLUS 20= 30 The word LET may be used or omitted in an assign- ment statement, but the execution of an assignment state- ment is faster if the word LET is used. The left portion of an assignment statement may be a simple variable (A through Z), STAT, or a memory location, which is in- dicated by an @ followed by a variable, a number, or an expression in parentheses. Here are some sample assignments: LETX = 7 X = 7 LETE = 1*R E = I*R STAT = #70 LET @A = 255 @(T + 36)=#FF Conditional assignments may be made without using an IF statement. The method hinges on the fact that all predicates are actually evaluated to yield — 1 if true and if false. Thus, if a predicate is enclosed in parentheses, it may be used as a multiplier in a statement as shown here: LETX= -A*(A>=0) + A*(A<0) This statement would assign the absolute value of A to X. Program Control NSC Tiny BASIC provides an assortment of program- control statements. The GO TO statement permits pro- gram branches to a specific line number or a line number called by an arbitrary expression. For example, 10 GO TO 50 would cause the program to jump from line 10 directly to line 50, but 10GOTOX + 5 would cause the program to jump from line 10 to line X + 5 . The value of X is variable, allowing dynamic con- trol of program execution at this point. The GOSUB and RETURN statements are useful when a computation or operation must be performed at more than one place in a program. Rather than write the routine over again each time it is needed, you employ a GOSUB instruction to "call" the computation or opera- tion (referred to as a subroutine). After the subroutine has been executed, a RETURN instruction (the last in- struction of the subroutine) causes the program to resume execution at the next line number following the original GOSUB instruction. An example is shown in figure 1. GOSUBs may be nested up to eight levels deep (including interrupt levels). 476 April 1982 © BYTE Publications Inc The IF. . .THEN statement allows program control to be modified by a logical test condition. The test condition follows the IF clause of the statement. When the test con- dition is true (nonzero), the THEN portion of the state- ment will be executed. When the test condition is false (zero), the THEN portion will be ignored and execution will continue at the next numbered line of the program. For example: 50 IF X>J THEN GO TO 140 NSC Tiny BASIC allows the omission of the word THEN from an IF. . .THEN statement. This omission, also allowed on some larger BASICs, enhances the clarity of the program. The previous example would become: 50 IF X>J GO TO 140 The DO. . .UNTIL statement is unique to NSC Tiny BASIC. Borrowed from Pascal, this statement is used to program loops, thus keeping GO TO statements to a minimum. The DO. . .UNTIL statement makes NSC Tiny BASIC programs clear in structure and easy to read. The following example shows the use of DO. . .UNTIL statements to print numbers less than 100: 10 PRINT 1: PRINT 20 PRINT 2 30 1 = 3 40 DO 50J = l/2 60N = 1 70 DO :REM I IS NUMBER TESTED REM J IS THE LIMIT REM N IS THE FACTOR REM SEEKS A DIVISIBLE FACTOR OF I 80N = N + 2 90 UNTIL (MOD(I,N) = OR (N> J)) 100 IF N>J PRINT I :REM NO DIVISIBLE FACTOR 110 1 = 1 + 2 120 UNTIL (I> 100) :REM ENDS THE SEARCH By enclosing a or more statements between the DO and the UNTIL < condition > statement (where the < condi- tion > is any arbitrary expression), you cause repetition of the enclosed statements as a group until the < condi- tion > evaluates to a nonzero number (a true condition). DO. , .UNTIL loops can be nested, and NSC Tiny BASIC will report an error if the nesting level becomes too deep (more than eight levels). The FOR. . .NEXT statement in NSC Tiny BASIC is identical to the FOR. . .NEXT statement in standard MAIN PROGRAM SUBROUTINE 10 LET X=5 20 B=X+8 50 GOSUB 200 60 X=A/B 200 Y=X+B/A 100 GOSUB 200 -110 X=X*B 250 RETURN-. \ I Figure 1: The effects of the GOSUB and RETURN statements in NSC Tiny BASIC. On the first GOSUB call (line 50), the order of execution follows the solid arrows. On the second GOSUB call (line 100), the order of execution follows the dashed arrows. April 1982 © BYTE Publications Inc 477 BASICs. A STEP function in the FOR statement may be used to specify the size of the increment in each iteration of the statement. In the absence of a specified STEP, NSC Tiny BASIC assumes a STEP value of +1. The value of the STEP may be either positive or negative. Starting and ending values of the FOR. . .NEXT loop are included in the FOR statement. The loop is repeated when the NEXT statement has been executed, provided the upper limit of the FOR statement has not been reached. When the upper limit is reached, the program will exit from the FOR. . .NEXT loop. NSC Tiny BASIC causes an error break if the variable in the NEXT statement is not the same variable as that used in the FOR statement, FOR. . .NEXT loops may be nested, and NSC Tiny BASIC will report an error if the nesting level becomes too deep; a depth of four levels of FOR loop nesting is allowed. A FOR loop will be executed at least once, even if the initial value of the control variable already exceeds its bounds before starting. The following program would print the odd integers less than 100: The program above requires the machine-language program described below to be loaded into address 1800 hexadecimal. ION = 100 20 FOR 1 = 1 TON STEP 2 30 PRINT I 40 NEXT I :REM UPPER LIMIT :REM START AT 1 WITH STEP OF 2 :REM PRINT A NUMBER :REM REPEAT (at line 20) 20) When increased execution speed is needed, you can use a LINK statement to transfer control from an NSC Tiny BASIC program to an INS8073 machine-language rou- tine. A statement of the form LINK < address > will cause transfer of control to the INS8073 machine- language routine, starting at the. specified address. Con- trol is transferred by execution of a JSR (Jump to Sub- routine) instruction. The INS8073 has two address pointers, P2 and P3, in addition to the program counter and the stack pointer. When a LINK statement transfers control to a machine- language routine, the routine can modify the pointers P2 and P3. The value of pointer P3 is unpredictable; P2 points at the starting location of the storage of A through Z variables. These variables are stored in ascending alphabetical order, two bytes each, low-order byte first. Here is an example: 10 LINK #1800 20 IF A = THEN PR "SENSE A IS LOW" 30 IF A = l THEN PR "SENSE A IS HIGH" 99 STOP >RUN SENSE A IS HIGH STOP AT 99 >RUN SENSE A IS LOW STOP AT 99 NSC Tiny BASIC trans- fers to address #1800 to read sensor. Program transfers back to NSC Tiny BASIC 1 TITLE SENSE 2 0000 .=01800 3 1800 06 LD A,S 4 1801 D410 AND A, =16 5 1803 6C02 BZ LOW 6 1805 C401 LD A,=l 7 1807 CA00 ST A,0,P2 8 1809 5C RET 9 0000 .END ;THIS PROGRAM READS SENSE A PIN ;TINY BASIC JUMPS HERE ;STORES AC- CUMULATOR INTO LOCATION OF VARIABLE A ;RETURN TO TINY BASIC The ON statement helps process interrupts. The format of the statement is: ON interrupt — #, line-number When the numbered interrupt (interrupt — #) occurs, NSC Tiny BASIC executes a GOSUB statement beginning at the line number given. If the line-number given is zero, the corresponding interrupt is disabled at the software level. Interrupt numbers may be 1 or 2. Use of the ON statement disables console interrupts (BREAK function). Interrupts must also be enabled at the hardware level by setting the interrupt-enable bit in the status register (e.g., using STAT = 1). Although the last line of a program does not have to be a STOP statement, use of a STOP in this way does help in debugging. The STOP statement may be inserted as a breakpoint in an NSC Tiny BASIC program. On en- countering a STOP statement, NSC Tiny BASIC prints a stop message and the current line number, then returns to the edit mode. Thus, you can see whether your program has reached the desired point. Any number of STOP statements may appear in the program. By removing the STOP statements one by one, you can test the program in parts until debugging is completed. Execution of a stopped program may be continued after the STOP by a CONT (continue) command. Other Useful Features The DELAY statement delays NSC Tiny BASIC for "expr" time units (nominally milliseconds, 1 through 1040). Delay gives the maximum delay of 1040 ms. The format is: DELAY expr For example: > 10 DELAY 100 Delay 100 ms. 478 April 1982 © BYTE Publications Inc The CLEAR statement initializes all variables to 0, disables interrupts, enables BREAK capability from the console, and resets all stacks (GOSUB, FOR. . .NEXT, and DO. . .UNTIL). For example: 10 ON (2,250) Break is disabled, Interrupt 2 is enabled. 40 LET B = 6000 50 LET @B = 100 60 LET 0@B 70 PRINT @6000 80 LETD = @(A + 10*D) Assigns 6000 to B. Stores decimal 100 in memory location 6000. Sets C equal to 100. Prints 100. Sets D equal to the value stored in memory location (A + 10*D). 300 CLEAR Break is reenabled, Interrupt 2 is disabled. The indirect operator is an NSC Tiny BASIC exclusive, at least in the realm of BASIC. This operator performs the functions of PEEK and POKE with a less cumbersome syntax. The indirect operator can access absolute memory locations and can service input/ output devices as well. Its utility is especially significant for microprocessors like the INS8073, for which interfacing is commonly performed through memory addressing. When an "at" sign (@) precedes a constant, a variable, or an expression in parentheses, that constant, variable, or expression is taken as an unsigned 16-bit address at which a value is to be obtained or stored. Thus, if an in- put device has an address of #6800 (hexadecimal), the statement LETX = @#6800 would input from that device and assign the value of the input to the variable X. If the address of an output device was #6801, the statement @#6801 = Y would output the least significant byte of Y to the device. The indirect operator accesses memory locations only one byte at a time. An assignment such as @A = 248 changes the memory location pointed to by A to 248 binary (1111 1000), since 248 can be expressed as one byte. However, an assignment such as @A = 258 changes the memory location pointed to by A to 2, because ex- pressing the value 258 causes a carry to a ninth bit, which is lost, as shown below: 258 10 A 1 0000 0010 extra one byte (stored into location to bit which A would point) Only the least significant byte of 258 (which is 2) is stored at the location to which A would point. In any place where a variable, such as B, would be legal, the construct "@B" (which means the byte located at the memory location whose address is the value of B) would also be legal. Here are some other examples: Parentheses are required when @ is applied to an expres- sion. More than one statement can be placed on one pro- gram line by placing a colon between the statements. This technique can improve readability of the program and can save memory space. Here is an example of the use of multiple statements: 200 PRINT "MY GUESS IS",Y:PRINT "INPUT A POSITIVE NUMBER";: INPUT X: IFX <=0GOTO200 If X is negative or zero, you will be instructed to enter a positive number, and the program will return to line 200 for a new guess. If you had entered a positive number correctly, the program would have proceeded to the next numbered line after line 200. You must use multiple statements per line with care. The above example shows that if the condition of the IF © MicroTech Exports 1980 GETS FILES ACROSS! With RE FORMATTER disk utilities you can read and write IBM 3740 and DEC KT-11 single density formatted diskettes on your CP/M K system. REFORMATTER enables you to access large system databases, improve data exchange with other organizations, increase program development capabilities, and use your micro in distributed processing. REFORMATTER programs feature bi-directional data transfer and full directory manipulation. ASCII /EBCDIC conversion provided with CP/M *-* IBM. MPiM is now fully supported. Program Data Sheets, Application Guides, and Machine Compati- bility Guides available. Each program $19500 from stock. Specify CP/M ** IBM or CP/M ** DEC. Order from MicroTech Exports, Inc., 467 Hamilton Ave., Suite 2, Palo Alto, CA 94301 □ Tel: 415/324-9114 □ TWX: 910-370-7457 MUH-AITOS □ Dealer and OEM discounts available. mm CP/M® is a registered trademark of Digital Research. W Circle 276 on inquiry card. April 1982 © BYTE Publications Inc. 479 statement is false, control passes to the next program line. Anything else on the line containing multiple statements will be ignored. String Handling To input string data, a statement of the form INPUT $ F where F is a starting address, is used. When the program reaches this statement during program execution, NSC Tiny BASIC prompts you with a question mark (7). All line-editing characters may be used (back space, line delete, etc.). If a control-U is typed to delete an entered line, NSC Tiny BASIC will continue to prompt for a line until a line is terminated by a carriage return. The line is stored in consecutive locations, starting at the address pointed to by F, up to and including the carriage return. For example, 20 INPUT $ A may also be written 20 INPUT $A and inputs a string to successive memory locations start- ing at A. An item in a PRINT statement can include a string variable in the form of $B. When the print statement is encountered during program execution, the string will be printed beginning at the address B up to, but not in- cluding, a carriage return. A keyboard interrupt will also terminate the printing of the string if the interrupt is detected before the carriage return. For example, 50 PRINT $B prints the string beginning at the location pointed to by "B". Characters in quotes can be assigned to string variables just as numerical values are assigned to other variables. A statement of the form $C = "THIS STRING IS A STRING" when encountered during program execution, would cause the characters in quotes to be stored in memory starting at the address indicated by C and going up to and including the carriage return at the end of the line. For example: 70 $D = "THIS IS A STRING WITH NO INPUT STATEMENT." A T is stored at location "D", an H at location "D + l", etc. Strings can be moved from one memory block to another. A statement of the form $A = $B (where A and B are addresses) will transfer the characters in memory beginning with address B to memory beginning with address A. The last character, normally a carriage return, is also copied. Note that a statement such as $(A + 1) = $A would be disastrous, because it fills all of RAM with the first character of $A. Here is an example of moving one memory block to another location: 10 A=TOP :REM A POINTS TO EMPTY RAM ABOVE TOP OF PROGRAM 20 C = TOP + 100 :REM C POINTS TO RAM 100 BYTES ABOVE A 30 D = TOP + 200 :REM D POINTS TO RAM 100 BYTES ABOVE C 40 INPUT $A :REM STORES CHARACTERS WHERE A POINTS 50 PRINT $A 60 LET $C = "IS THE STRING INPUT AT LINE 10" 70 $D = $C :REM STORES CHARACTERS WHERE D POINTS 80 PRINT $D Commands The NEW command establishes a new start-of- program address equal to the value of "expr". NSC Tiny BASIC then executes its initialization sequence, which clears all variables, resets all hardware /software stacks, disables interrupts, enables BREAK capability from the console, and performs a nondestructive search of RAM. If the value of "expr" points to a ROM (read-only memory) address, the NSC Tiny BASIC program that begins at that address will be automatically executed. The NEW command does not alter memory (including the end-of -program pointer used by the editor). For example: > NEW 1000 NEW used without an argument sets the end-of- program pointer equal to the start-of -program pointer, so that a new program may be entered. If a program already exists at the start-of -program address, it will be lost. For example: > NEW 1000 Sets program pointer to 1000 > NEW Sets end-of -program pointer to 1000 The RUN command runs the current program. For example: > RUN Execution begins at lowest line number 480 April 1982 © BYTE Publications Inc The CONT (continue) command continues execution of the current program from the point where execution was suspended (via a STOP, console interrupt, or reset). An NSC Tiny BASIC program that is executing can be in- terrupted by pressing the BREAK or RESET keys on the keyboard. Execution can be resumed by entering the CONT command. For example: >RUN THIS IS THE STRING INPUT AT LINE 10 THIS IS THE STRING INPUT AT LINE 10 THIS IS THE STRING INPUT AT LINE 10 THIS IS THE STRING INPUT AT LINE 10 Press BREAK or RESET. A c >CONT THIS IS THE STRING INPUT AT LINE 10 THIS IS THE STRING INPUT AT LINE 10 And so on... The LIST(expr) command lists the current program (optionally starting at the line number specified by "expr"). For example: > LIST 10 10 INPUT $A 20 PRINT $A 30 LET $C = "IS THE STRING INPUT AT LINE 10" 40 $D = $C 50 PRINT $D Conclusion NSC Tiny BASIC and the INS8073 Microinterpreter Chip offer many advantages to the programmer. NSC Tiny BASIC'S indirect operator represents a substantial improvement over the usual PEEK and POKE statements. The DO . . . UNTIL statement brings the advantages of structured programming into the realm of Tiny BASICs for the first time. These and other advanced features of NSC Tiny BASIC offer you the convenience of a high- level language as well as new possibilities for elegance and efficiency in process-control and other applications often reserved for assembly language. Furthermore, with NSC Tiny BASIC and the INS8073, transferring programs from RAM to ROM is remarkably simple. Because the INS8073 executes ASCII (American Standard Code for Information Interchange) data, if the program will run in RAM, it will run in ROM. You don't have to put anything in ROM except what you put on paper. Programmers have already used the INS8073 and NSC Tiny BASIC for a wide variety of applications, including precision measurement of conditions in oil wells and testing the feasibility of the digital design of an FM tuner. In the coming years, the INS8073 and NSC Tiny BASIC will simplify many other complex tasks. ■ CATCH THE S-100 INC. BUS! 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Priced from $129-389. Details from George Masters: #TNW CORPORATION Dept. B. , 3444 Hancock St., San Diego, CA 92110 (714) 296-2115 • TWX 910-335-1194 VISA/MasterCard • Dealer Inquiries Welcome Circle 417 on inquiry card. April 1982 © BYTE Publications Inc 481 System Notes Easy Entry Program for Radio Shack's Color Computer Tim Field 1021 Shenandoah Drive Lafayette, IN 47905 Radio Shack's versatile new TRS-80 Color Computer packs a big bang for a small cost. The power of its 6809 microprocessor is the computer's biggest attraction. To take full advantage of the 6809, you must develop machine-language programs. The Easy Entry program is a short BASIC program that will greatly help you enter machine-language programs for the Color Computer. By no means does it replace an assembler, but Easy Entry will save you many hours of arduous and error-prone work until you get one. (For more information, see "A Closer Look at the TRS-80 Color Computer/' October 1981 BYTE, page 334.) The Color Computer's BASIC provides the necessary keywords (PEEK, POKE, and USR) to permit entry of machine-language programs. However, using these com- mands to enter a short program is soon cumbersome and Plug-in Programming // you re serious about assembly-language programming for the Color Computer, you'll need an assembler/ editor, which allows much more efficient programming. The Color Computer's unique design makes it possible to purchase plug-in ROM cartridges containing editor/ assembler programs. Two examples are the Radio Shack Editor/ Assembler Program Pack (part number 263250, $39.95) and the Micro Works Software Develop- ment System (SDS8QC, $89.95). With these utility programs in ROM, the constant problem of loading and relocating pro- grams is eliminated and almost the entire RAM space is available to your program. . .SJW. tedious. You must develop, code, and hand-assemble the program, enter it into memory, and test and debug it. And the entry is not that simple. All values must be converted into decimal values be- tween and 255 before they can be POKEd into the Color Computer. Op codes must be individually converted to decimal from their hexadecimal format in the 6809 data sheets. Negative values must be converted to the form understood by the computer. Decimal addresses greater than 255 must be broken down into two-byte values. Then, after completing all these conversions, each value must be individually POKEd into memory. The Easy En- try program (see listing 1) handles all conversions and POKEs each converted value into its proper memory locations. Conversions Normal Decimal Entries. A single byte value (0 to 255 or — 127 to 127) may be specified simply by responding with the desired value on a prompt from the program, For example, to POKE value 98 decimal into the next memory location, input 98 at the next prompt. Hexadecimal to Decimal Conversions. PEEK and POKE accept and return decimal values for specified memory locations. This is terrific because we live in a decimal-reliant society and are uncomfortable working directly with hexadecimal values. Unfortunately, com- puters "think" in binary (0s and Is), which is not easily converted to decimal (and vice versa). However, binary to hexadecimal to binary conversions are relatively straightforward, and the resulting hexadecimal values occupy considerably less room (two characters per byte for hexadecimal versus eight characters for binary). 482 April 1982 © BYTE Publications Inc Listing 1: The Easy Entry program, written in BASIC for the Color Computer. A complete description of the program is given in table 1. 10 CLS»CLEARC4P!)iINPUT"STARTt«>A$:Asa75:r,0$URaCHi 20 AcyAL(AS) 30 PR I NT A | jINPUT ,, NEXTj"jCS|IFC55"*"THENEN0 40 A**RIGHT* (C$, LEN(C$)-1) ! D$=LEFT$ (.1%, 1) 50 IFD$«". ,, THENGOSUB200ELSEIFD$a M ,"TWENGOSUg3^WELSEA$ = CI:GOSUBl/0 60 ASA-HIGOTO30 100 UsVAL(AJ):IFLEFT$(AJ,n = "- n THENU = 256+U 110 POKEAt UjRETURN 200 UsVAL(A$):BxABS(U) :Vx-i 210 IFU<0THENU=BtKslElSEK*0 220 IFU>«0THENU«U-256:VsV+l:GOTO220 23« U*B-V*256»IFKalTHENU=256-U«V=255-V 2U0 POKEA,Vl A»A+1|P0KEA,U:RETURN 300 C«LEN(A$) »GOSUS«00j JsE:CsC-l |GOSUB40H 310 P0KEA#16*E+J|RETURN 400 IFC9THENE*E-7 420 RETURN 500 G$» , 'O":GOSUB700t INPUT "START*" } X : INPUT "END? " jY 510 PRINT«-l,XjPRINT#-l,Y 520 FORZsX TO Y j A*PEEK( Z) :PRINT«- 1 , A • NEXTZ t CLOSE- 1 :FNO 600 G$« H I":GOSUB700lINPUT*-l,X:INPUTa-l, Y 610 PRINTX # Y:As275lBsX:UsXiV = -HGO$UB2l0 620 FORZsX TO Y « INPUT*-1, A »POKEZ, A : NEXTZ : CLOSE- 1 s ENO 700 INPUT-FILE NAMEl"|F$:OPENG$,-l,F$;RETUPN April 1982 © BYTE Publications Inc 483 System Notes -^^-^^— ^^— ^ Since op codes are often specified in hexadecimal and must be converted to decimal before being POKEd into memory, the program handles the conversion for you. To indicate that the current entry is a hexadecimal value, merely precede it with a ";". The acceptable values must be in the 00 to FF range. For example, ;7F tells the pro- gram to convert hexadecimal value 7F to decimal 127 before being POKEd into memory. Decimal to Decimal Conversions. You might question the necessity of converting a decimal value to decimal. POKE will accept values between and 255; if a value ex- ceeds 255, it must be broken down into multiple bytes, which are then POKEd into memory in order, from the most significant to the least significant byte. For example, the decimal value«3500 is broken down into a most-significant-byte value of 13 (decimal) and least- significant-byte value of 172. This process usually involves manually converting the original value into its hexadecimal equivalent (3500 decimal to ODAC hexadecimal), breaking the hex- adecimal value into two bytes (0D and AC), and then reconverting these two bytes to decimal (OD to 13 and AC to 172). The program will accept any input value which is preceded by a ".", convert that into two bytes of decimal, and POKE both into memory. This gives a value range of to 65535. Negative Decimal to Positive Decimal. As previously mentioned, the POKE function takes values between and 255. If you wish to POKE a negative number into memory (e.g., a negative branch offset), you must con- vert the negative value to its positive equivalent. To understand how a negative value has an equivalent positive value, we must look at how the computer "knows" if a value is positive or negative. When seeking a data value, the computer expects to use the most significant value bit as the sign bit. If the value is 8 bits long, bits to 6 are the value bits and bit 7 (the eighth bit) specifies whether the value is positive or negative. If the sign bit indicates a negative value, the Listing 2: This sample program paints the screen purple and then returns to BASIC control Memory locations 1024 to 1536 are used for video memory in the Color Computer. Value 191 paints one block on the screen purple. LD8 191 J C6 191 LDY 1024 f 10 BE 1024 STB ,Y* | E7 A3 C*PY 1536 | 10 8C 1536 BLT -8 ? 20 -8 RTS » 19 SAVE $$ [appkz computer APPLE COMPUTER SYSTEMS SOLD ONLY IN STORE. CALL FOR PRICES. RAM MEMORY FOR TRS-80. APPLE II 16KSET4116's (200 NS) 24.95 General Information: We carry a large selection of hardware and software by other companies. Send for our catalog. We are an authorized repair center for APPLE, ATARI, NORTH STAR, AND EPSON. DISCOUNT PRICES A ATARI 400 16K 349.00 800 16K 699.00 410 Recorder 89.00 810 Disk 449.00 822 Printer 359.00 825 Printer 779.00 830 Modem 159.00 850 Interface Module 179.00 CX853 RAM 89.00 CX70 Light Pen 64.00 CX30 Paddle 18.00 CX40 Joystick 18.00 VERBATIM DISKETTES Box of 10 5 W 29.50 Box of 10 8" 39.50 NorthSter HRZ-2Q-64K HRZ-1Q-64K-HD-5 HRZ-1Q-64K-HD-18 5 MB HARD DISK 18 MB HARD DISK 2350.00 4195.00 SAVE $$ PRINTERS EPSON MX-70 299.00 MX-80 469.00 MX-80 F/T 569.00 GRAFTRAX 90.00 INTERFACE (APPLE) 75.00 CABLE (APPLE) 22.50 IDS 560G 1450.00 PRISM 1795.00 NEC 3510 35CPS 1995.00 7710 55CPA 2650.00 8023A 599.00 OKIDATA MICROLINE80 389.00 MICROL1NE82A 549.00 MICROLINE83A 849.00 MICROLINE84 1245,00 C.I.T.O.H. STARWRITER 25CPS 1595.00 STARWRITER 45CPS 2195.00 FORMS TRACTOR 275.00 PRICES SUBJECT TO CHANGE WITHOUT NOTICE. MARYLAND RESIDENTS ADD 5% SALES TAX FREDERICK COMPUTER PRODUCTS, INC. Store Hours: MON. THRU THURS. 9:30 AM-9:00 PM FRI. AND SAT. 9:30 AM-5:00 PM 5726 INDUSTRY LANE FREDERICK, MD. 21701 TO ORDER CALL: (301) 694-8884 484 April 1982 © BYTE Publications Inc Circle 465 on inquiry card. Listing 3: This listing shows an Easy Entry program sample run. The machine-language program in listing 2 has been entered. RUN START*? 3000 {Start POKElng at address 3000) 30<"« NEXTl? »C6 {At address 3000 poke hex value C6> 3001 NEXTj? 191 (Poke single byte decimal 191) 3002 NEXT;? |10 3003 NEXT:? f 8E 300a NEXT!? .1024 (Poke double byte decimal 191,, .takes two bytes) 300t> NEXT:? jE7 3007 NEXT;? ;A0 3008 NEXT;? »10 3009 NEXT;? |8C 3010 NEXT;? ,1536 3012 NEXT;? |20 3013 NEXT;? -8 {Poke negative single byte decimal -8) 3014 NEXT;? ;39 3015 NEXT;? * (Done with entering program) OK {Computer response) YsUSR(l) {Execute program) EVYE TOLL-FREE SUBSCRIPTION LINE 1-800-258-5485 the small systems j ournal New Hampshire Residents Dial 924-9281 The Quickest Way To . Change or Correct an Address • Order a Subscription • Give a Friend a Gift Subscription • Renew a Subscription • Inquire about a Subscription We are waiting to help you. Call us between: 8:30-4:00 Mon.-Fri. (Eastern Time) April 1982 © BYTE Publications Inc 485 System Notes - \ • - j • ■■ value bits specify the two's complement of the absolute value. This provides an effective value range for 8 bits between —127 and +127. Thus, 255 decimal indicates a negative value and, taking the two's complement of the value bits, we find that we have specified a — 1. The program automatically converts negative decimal values into their positive equivalents. The value may be either 8 or 16 bits. Operation The program is simple to operate. On initiation, the program prompts you for the starting address for the first byte of the machine-language program. The address is stored in memory locations 275 and 276, so a simple USR command after entry of the machine-language program executes that program. You are then prompted for each value in sequence, starting at the beginning address. The current address is displayed with each prompt, and this entry loop continues until you enter an asterisk (*) to signify termination of the program-entry session. The program then returns control of the computer to you. (See listings 2 and 3 for examples of an Easy Entry pro- gram sample run.) Saving and Loading Machine-Language Programs Once you enter and debug a machine-language pro- gram, you can save it on tape. Since the Color Computer's BASIC does not allow you to directly save 8" DUAL DENSITY CONTROLLER • UP TO 4 MEGABYTES ON LINE • DOS 3.2, 3.3 COMPATIBLE • PASCAL*" AND CP/M tm DUAL DENSITY NOW AVAILABLE • IBM tm 3740 or SYSTEM 34 FORMATTED • SHUGART, QUME, SIEMENS COMPATIBLE • IMMEDIATE DELIVERY Available at your local APPLE Dealer: $595. zE> SORRENTO VALLEY ASSOCIATES 11722 SORRENTO VALLEY RD. SAN DIEGO, CA 92121 TWX 910-335-2047 machine-language programs, I have included two routines (lines 500 through 700) that save and load the programs for you. If you have a 4 K-byte machine and are developing a large machine-language program, you can separate these two routines from the main program and load them only when ready to save your program. Lines 210 through 240 and 500 through 700 must be used. If you wish to leave the program conveniently intact, there are still more than 1700 bytes available for the 4K-byte computer. (If you have 16K bytes of memory, you naturally have lots of space.) You should limit machine-language programs to address 2500 decimal and up. Type "RUN 500" to save a machine-language program. You will be prompted for the desired file name for pro- gram storage and the starting and ending address of the machine-language program. All bytes between the start- ing and ending addresses are saved on tape. For example, you might have a program with a main loop at address 2500 through 3000, subroutines at 3100 through 3150 and 3400 through 3450, and a data table at 3475 through 3500. You would want to save your program from ad- Lines Purpose Main Routine 10 20-30 40-50 60 Initialize program. Prompt user for starting address and place into 275-276. Prompt input from user ... if "*" then end program. Determine type of input. Jump to appropriate subroutine for conversion and POKEing of value. Move to next address and repeat. Subroutines 100-110 Value is between -255 and +255. If negative, negate input. POKE value. 200-240 Input (A$) is a decimal value to be converted into two eight-bit values. Line 220 loops, subtracting 256 from U per loop until U is less than zero. Then, the most significant byte is V; least signifi- cant byte is U. POKE both bytes and increments POKE pointer A. 300-310 Input is hexadecimal (00-FF). The value is calculated by finding the decimal equivalent of each ASCII value and then adjusting these values to give ap- propriate results. The final value is then calcu- lated by adding the least significant value (cor- responding to least significant hexadecimal entry) to 16 times the most significant entry. 400-420 Input single hexadecimal character (character C in string A$) and return the equivalent decimal value in variable E. If C< 1 then return E = 0. Save/Load Routines (execute with commands) 'RUN 500" or "RUN 600" 500-520 600-620 700 Input file name, starting and ending addresses, and save specified memory block to cassette tape. Input file name. Load file from cassette into memory address found at start of data file. Poke starting address into 275-276 to allow the USR command to execute loaded program. Routine used by 500 and 600. Used to fetch file name of desired file to be saved or loaded. [Table 1: The Easy Entry program routines and their functions. 486 April 1982 © BYTE Publications Inc Circle 378 on inquiry card. Circle 88 on inquiry card. dress 2500 to 3500. All unused addresses between the routines and the tables are also saved. To load a previously saved machine-language pro- gram, type "RUN 600". You will be prompted for the file name of the program to be loaded. The program then reads from the tape the starting and ending addresses used when the program was stored, sorting the program in those memory locations. The starting address of the program being loaded is automatically converted into two bytes and POKEd into memory locations 275 and 276. Thus, if you have a complete program loaded, you can immediately execute it by typing Y = USR(1). Since Easy Entry loads machine-language programs into specific memory locations, you can save parts of programs, load them all separately, and execute a pro- gram. For instance, you might be developing several pro- grams, each using a large subroutine. If the subroutine is subject to changes, or if you store the subroutine with each separate program, it is easy to lose track of revi- sions. However, if you want that routine at a permanent location (say address 3700 through 4100), you can save it separately from other programs. Then, wishing to ex- ecute one program, you load the subroutine, load the program's main body, and execute. Be certain that the proper address is loaded into memory locations 275 and 276 so that the computer knows where to look when you execute the USR command. How the Routines Work The save and load routines treat each machine- language program byte as data. To save a program, each byte is consecutively PEEKed at and then sent to the tape using the PRINT#-1 command. The first two pieces of data stored in the data file are the starting and ending ad- dresses of the machine-language program being stored. When the load routine is executed, it reads these two ad- dresses, reads all data from the tape, and POKEs it into the specified memory block. You might think that saving a large machine-language program to tape and writing each individual byte to tape separately would be time consuming. Thanks to the PRINT#-1 statement's design, this isn't so. Apparently, the Color Computer's BASIC sets aside a buffer used to store the PRINT#-1 data values. When this buffer is full, data is sent to the tape and the buffer is refilled, allowing you to save a machine-language program of 2 K bytes in about 30 seconds. The time required to load a program is similar. The Easy Entry program requires only about 450 bytes of memory. For a 4 K-byte Color Computer, this leaves almost 2000 bytes of available memory to store machine- language programs. A lot can be accomplished in 2000 bytes of machine language. Your machine-language programs may be entered starting at address 2200. Little error checking is included in the program to keep it as small as possible. After enter- ing a few values, you should become adept at using the program and save yourself many hours. ■ You're different. And C may be the program- ming language you've been looking for. To get you interested, we sell a simple compiler called Small-C for only $1 9.95. If you need more features, try our excellent CW/C® compiler for just $49.95. (It supports a surprisingly large subset of C.) And if you would like to have the complete source code for a great C compiler, then Q/C for $95 is what you need. All these compilers run under CP/M-80®. Write for detailed information. You'll find that we're different too. CP/M is a trademark of Digital Research. CW/C is a trademark of The Code Works. theCODE WORKS 5266 Hollister Suite 224 Santa Barbara, CA 931 1 1 (805) 683-1585 Clear up your confusion — read the instructions in your tax package. A public service message from tne Internal Revenue Service April 1982 © BYTE Publications Inc 487 STATISTICAL SOFTWARE ELF — Stepwise regression, fac- tor analysis, correlation coeffi- cients, crosstabs, simple statistics, t-tests, ANOVA, stepwise discrimi- nant analysis, all BASIC transfor- mations and more. $200,00 TWG/ARIMA - Box-Jenkins for seasonal and non-seasonal models, identification, estimation and fore- casting. Price: $300.00. Each includes a database manager, numeric software key- pad, and is menu-driven. Each re- quires an Apple II with Applesoft, 48K, and DOS 3.3. For further information, write 3907 Lakota Road P.O. Box 10114 Alexandria, VA 22310 *Apple II and Applesoft are trademarks of the Apple Computer Company ELIZA IS HERE! AT LAST! A FULL IMPLEMENTATION of the original ELIZA program It now available to run on your microcomputer) Created at MIT In 19C6, ELIZA has become the world's most celebrated artificial Intelligence demonstration program. ELIZA Is a non-dtrectlve psychotherapist who analyzes each statement as you type It and then responds wtth her own comment or question — and her remarks are often startllngly appropriate! Designed to run on a large mainframe, ELIZA has hitherto been unavailable to personal computer users except In greatly stripped down versions lacking the sophistication which made the original program so fascinating. Now, our new microcomputer version possessing the FULL power and range of expression of the original Is being offered at the Introductory price of only $25. And If you want to find out how she does It (or teach her to do more) we will Include the complete Sou re* Program tor only $20 additional. Order your copy of ELIZA today and you'll never again wonder how to respond when you hear someone say "Okay, let's see what this computer of yours can actually do!" ELIZA IS AVAILABLE IN THE FOLLOWING DISK FORMATS: 1 . Standard 8 Inch single density tor all CP/M based computers $25 for ELIZA.COM — add $20 tor Microsoft BASIC-80 Source 2. 5V, Inch CP/M for Apple II equipped with Z-80 SoftCard $25 for ELIZA.COM — add $20 for Microsoft BASIC-80 Source 3. 57* Inch tor 48K Apple II with Applesoft ROM and DOS 3.3 $25 for Protected File — add $20 for Unprotected Source ARTIFICIAL INTELLIGENCE RESEARCH GROUP f i— M ' 921 NORTH LA JOLLA AVENUE ■■■■ LOS ANGELES. CALIFORNIA 90046 *2=L^— I (213)656-7368 (213)654-2214 WmSn& m MC, VISA and CHECKS ACCEPTED ft Scotch DISKETTES SAVE 40% £&£% 5y rt Specify soft, Price/ 10 /4 1 or 1 6 sector #744 i side/sgl dens $26.70 #744D 1 side/dbl dens 31.20 #745 2 sides/dbl dens 38.40 8f i Specify soft or 32 sector #740 1 side/sgl dens 27.30 #741 1 side/dbl dens 35.80 #743 2 sides/dbl dens 43.60 CHECKS - VISA ~ MC - C.O.D. (3 13) 777-7 780 ADD $2 SHIPPING LYBEN COMPUTER SYSTEMS 27204 Harper Ave. St. Clair Shores, Ml 48081 Authorized Distributor ISlSk Information Processing Products Vf^CT Circle 437 on inquiry card. Circle 40 on inquiry card. Circle 241 on inquiry card. DISKETTES CASSETTES Error-Free 5V4-inch Diskettes (MD 5) single-sided, soft sector, single or double density, reinforced hub. Item Qty 10 Qty 50 MD-5 $25.00 $110.00 C-10 C-20 C-60 C-90 I 7.50 9.00 11.50 15.00 $ 32.50 39.00 50.00 70.00 UPS SHIPPING INCLUDED in Continental USA CA Customers add taxes MICROSETTE 475 Ellis St., Mt. View, CA 94043 (415)968-1604 Circle 274 on inquiry card. RAM: 64K-200nS (128 refresh) 8/$79 Color R.F. Modulator Kit: - $13.79 14A S-100 Power Supply Kit-$29.95 (for line cord and circuit breaker, add $8.95) .*tt\§ -q. 47-63 Hz, 95-250 VAC with RFI filter included. = lbV @^ A Disk Power Kit— 24V/5A - $19.95 New! RGB D,splays • High Contrast Black-Stripe Tube • Ultra Stable Convergence • 90 Day Warranty • 15.7 KHz Mlcroangalo CAT 100, IBM 13"- $349oo 525x420 lines, 32 lbs 19"- $37900 525 x 620 lines, 48 lbs. (Displays 80 characters on IBM)"* Actlva 12' Cable to IBM wtth "Intensity" Input— $75.00 Deatin' Electronics 735 Loma Verde, Palo Alto, CA 94303 • 415-493-5930 Circle 141 on inquiry card. TYPESETTING from your own COMPUTER Type your manuscripts, catalogs, or other text into your word processing com- puter. Send it to us on a diskette or via- a modem transmission and we'll send you camera ready film copy. Computer typesetting provides high quality, easy to read copy at a fraction of the cost of conventional typesetting. Call or write for instructional brochure that includes typestyle selections, format- ting instructions, and examples. Dream Electronics 131 N.W. 2 nd. St. 1-503-7524833 Corvallis, Oregon 97330 Circle 152 on inquiry card. FOR YOUR mm .■■■■iii, jgcippkz HARDWARE AND SOFTWARE FREE CATALOG OVER 350 PRODUCTS SPECIAL OFFER wabash® diskettes Unique SR-3000 Formulation - 1 00% Certified Error Free - Hub Rings Installed on 5W 5 1 /4 M SS/SD $2 1 .95/BX DS/DD $29.95/BX 8" SS/SD S23.75/BX DS/DD $36.75/bx ONE TIME ONLY - ONE BOX/CUSTOMER AskForOurS-100and Related Products Catalog 2.4MB NEC 8" FLOPPY DISKS SUBSYSTEM $1675 FETCH COMPUTER PRODUCTS DIVISION OF: ALMALY TRADING CORPORATION 8135 S.W. 17 STREET, MIAMI, FL 33155 TELEX: 51-9602 "ALMALY MIA" 800-327-2251 Apple is a Registered Trademark of Apple Computers ANALOG mm> DIGITAL DIGITAL** ANALOG CONVERSION MODULES SOFTWARE 0AIN CONTROL c>ord test S-100 Pro IS Mh able high and low inputs gain ■niiiJ 16 channel anqU programmable gain instrt For additional details about the ad-ioo-4 and other fine California Data Corporation 100% individually tested, high reliability products, circle the reader service card number below or for faster response write or call us. CALIFORNIA DATA CORPORATION 3475 Old Conejo Road, Suite C-10 Newbury Park, CA 91320 (805) 498-3651 WANTED: APPLE, IBM, TRS-80, CP/M SOFTWARE Westico is a publisher and distributor of professional software for microcomputers. If you have a new program ready for distribution or want your existing programs to reach a larger market, contact; Phillip Woellhof, V.P. Mktg. Westico, Inc. 25 Van Zant Street Norwalk, CT 06855 (203) 853-6880 To increase your profits, take advantage of Westico's worldwide promotion and distribution. WESTICO The Software Express Service Circle 16 on inquiry card. Circle 72 on inquiry card. Clubs and Newsletters Atari Club In Virginia The recently formed Virginia Atari Club meets at 5 p.m. on the second Thurs- day of the month in the NASA Langley Research Ac- tivities Building (1222) in Hampton, Virginia. For more information, contact Olaf O. Storaasli, 109 Five Forks Ln., Hampton, VA 23669, (804) 851-4936. DATAmerica A newsletter packed with games, reviews, articles, soft- ware exchange, and pro- grams is available from DATAmerica Computer User's Group. The group's in- terests embrace most popular computers, including the Ap- ple II, TRS-80, Sinclair, Atari, PET, and VIC-20. Membership fees are $10 per year. A sample issue of the newsletter is available for $1. Contact DATAmerica, 312 East 84 St. #1A, New York, NY 10028, or through the Micronet RUN MLOM. XBA[ 70265, 742]. International Service Association Formed The International Associa- tion of Service Companies (IASCO) has been formed to provide specialized support services to independent ser- vice companies supporting mini- and microcomputer systems. To aid the indepen- dent service organization, IASCO has established a Board of Governors to coor- dinate the activities of several specialized industry commit- tees. The Board's goals hinge around the development of service standards of perfor- mance for its membership, the implementation of cen- tralized information centers to aid members, and to prepare and coordinate both technical and managerial ed- ucational programs for mem- bers. IASCO is currently pre- paring a support profile list- ing the various locations throughout the United States and Canada serviced by its membership. This informa- tion will be made available to interested parties. Service companies seeking IASCO membership will be required to meet minimum standards of service perfor- mance, service times, test equipment availability, and technical capability. For more information, contact S. Michael Smith, 1409 Centre Circle Dr., Downers Grove, IL 60515, (312) 620-8750. Color Computer Club Started Rohit Gupta has started a new computer club for TRS-80 Color Computer owners and users. Annual dues are $4, which includes a monthly newsletter on Color Computer developments. Contact Rohit Gupta, 28 Friars Ln., Springfield, IL 62704. New Zealand Computer Hobbyists Micro, the official publica- tion of the New Zealand Microcomputer Club, overflows with news of club projects and activities, classified advertisements, software library happenings, and notes from user groups. The club is investigating the chances of setting up a com- puterized bulletin-board ser- vice and is trying to stock its magazine library. The club would like to discuss the possibility of exchanging publications with groups from overseas. Contact the New Zealand Microcomputer Club Inc., POB 6210, Auckland, New Zealand. Apple Club Open to Hobbyists Membership in the Big Red Apple Club is open to anyone who, for geographical reasons, is unable to belong to a local club. All club business is conducted through the monthly news- letter, The Scarlett Letter, which also contains pro- grams, utilities, technical tips, and educational applica- tions. A free software library is maintained. Annual fees are $12. The club is a member of the International Apple Corp. Contact John Wrenholt, Big Red Apple Club, 1301 North 19th, Nor- folk, NE 68701, (402) 379-3531. Apples Thrive Down Under The Apple Users Group (Sydney) has formalized its objectives in a constitution and has elected an executive committee to direct the ac- tivities of its large member- ship. The club meets at the Sydney Grammar School, Science Auditorium, on the second Monday of the month at 6:30 p.m. The group main- tains a software library and produces a monthly newslet- ter, Applecations. Contact the Apple Users Group (Sydney), POB 505, Bankstown, New South Wales 2200, Australia, or call Colin Rutherford, (02) 520 0926. ■ P&T CP/M®2 Supports Hard Disk Storage for the TRS-80 Model II P&T CP/M 2 now supports two popular hard disk subsystems for the Mod II; thus you can combine all the features of the best CP/M for the Mod II with the speed and capacity of the hard disk drives. Cameo Electronics • uses mature cartridge disk technology for maximum reliability • supports up to 4 drives • removable cartridges make backup and data transfer fast and easy Corvus System • support for 10 and 20 Mbyte drives • special mirror utility allows backup by logical drive • supports up to 4 drives Price; $250 (FOB Gofeta) for P&T CP/M 2-hard disk version (CA residents add 6% sales tax) PICKLES & TROUT P, O. BOX 1206, GOLETA. CA 93116. (805) 685-4641 CP/M is a registered trademark of Digital Research. TRS-80 is a trademark of Tandy Corp Circle 331 on inquiry card. April 1982 © BYTE Publications Inc 489 Books Received Apple Pascal Games, Douglas Hergert and Joseph T. Kalash. Berkeley, CA: Sybex, 1981; 371 pages, 17.2 by 22.3 cm, softcover, ISBN 0-89588-074-1, $14.95. The Apple II Blue Book, A Complete "Where to Find It" Book of Software, Hard- ware, and Accessories for the Apple II, WIDL Staff. Chicago, IL: WIDL (5245 West Diversey Ave.), 1981; 131 pages, 21 by 26.5 cm, softcover, ISBN none, $19.95. Computer-Assisted Data Base Design, George U. Hubbard. New York: Van Nostrand Reinhold, 1981; 285 pages, 14.5 by 22.3 cm, hard- cover, ISBN 0^42-23205-5, $24.95. The Captain 80 Book of BASIC Adventures, Robert Liddil. Tacoma, WA: 80- Northwest Publishing, 1981; 252 pages, 20.5 by 27 cm, softcover, ISBN none, $19.95. Computing Using BASIC, An Interactive Approach, Tonia Cope. New York: Halsted Press, 1981; 351 pages, 14.5 by 22.3 cm, soft- cover, ISBN 0-470-27280-5, $19.95. Data Models, DionysiosC. Tsichritzis and Frederick H. Lochovsky. Englewood Cliffs, NJ: Prentice-Hall, 1982; 381 pages, 17.5 by 23.6 cm, hard- cover, ISBN 0-13-196428-3, $24.95. A Dictionary of Minicom- puting and Microcomputing, Philip E. Burton. New York: Garland STPM Press, 1982; 347 pages, 14.5 by 22.3 cm, hardcover, ISBN 0-8240- 7263-4, $42.50. Directory of Online Data- bases, Volume 3, Number 1 (Fall 1981), compiled and In Less Than 3 Minutes Your IBM Model 50, 60, or 75 Electronic Typewriter can be an RS232C PRINTER or TERMINAL CALIFORNIA MICRO COMPUTER Models 5060 and 5061 can be installed easily and require NO modifications to the typewriter. For additional information contact: CALIFORNIA MICRO COMPUTER 9323 Warbler Ave., Fountain Valley, CA. 92708 (714)968-0890 edited by Ruth N. Cuadra, David M. Abels, and Judith Wanger. Santa Monica, CA: Cuadra Associates, 1981; 186 pages, 21 by 27.5 cm, soft- cover, ISSN 0193-6840, $29.95. Electronic Circuits and Ap- plications, Bernard Grob. New York: McGraw-Hill, 1981; 468 pages, 18.5 by 23.5 cm, hard- cover, ISBN 0-07-024931-8, $20.95. 55 Color Computer Pro- grams for the Home, School and Office, Ron Clark. Woodsboro, MD: Arcsoft Publishers, 1981; 127 pages, 13.5 by 21 cm, softcover, ISBN 0-86668-005-5, $9.95. The Index, The Ultimate Index for All Personal Com- puter Users, W. H. Wallace. St. Ann, MO: Missouri In- dexing (POB 301), 1981; 489 pages, 13 by 20.5 cm, soft- cover, ISBN none, $14.95. Instant Freeze-Dried Com- puter Programming in BASIC, Jerald R. Brown. Beaverton, OR: Dilithium Press, 1982; 193 pages, 20.7 by 27.5 cm, softcover, ISBN 0-918398- 57-6, $12.95. Introduction to Computers and Computer Science, 3rd edition, Richard C. Dorf. San Francisco, CA: Boyd & Fraser Publishing Company, 1981; 617 pages, 16.4 by 23.8 cm, hardcover, ISBN 0- 87835-113-2, $18.95. Introduction to Word Pro- cessing, Hal Glatzer. Berke- ley, CA: Sybex, 1981; 205 pages, 14.5 by 22.3 cm, soft- cover, ISBN 0-89588-076-8, $12.95. JCL in a System 370 En- vironment, Barry L. Bateman and Gerald N. Pitts. Boston, MA: CBI Publishing, 1982; 182 pages, 18.5 by 23 cm, softcover, ISBN 0-8436-1606-7, $16.95. Knowledge-Based Systems in Artificial Intelligence, R. Davis and D. B. Lenat. New York: McGraw-Hill, 1982; 490 pages, 23.5 by 16.5 cm, hard- cover, ISBN 0-07-001557-7, $39.50. Pascal: An Introduction to Methodical Programming, 2nd edition, W. Findlay and D. A. Watt. London, Eng- land: Pittman Books Ltd., 1981; 404 pages, 14.5 by 22.5 cm, softcover, ISBN 0-273- 01714-4, £5.95. Programming in B ASIC- Plus, Jasper J. Sawatzky and Shu-Jen Chen . New York : John Wiley & Sons, 1981; 273 pages, 20.8 by 27.4 cm, soft- cover, ISBN 0-471-07729-1, $14.95. The UCSD Pascal Hand- book, Randy Clark and Stephen Koehler. Englewood Cliffs, NJ: Prentice-Hall, 1982; 356 pages, 15 by 23 cm, hard- cover, ISBN 0-13-935544-8, $19.95. The Word Processing Handbook, Russell Allen Stultz. Englewood Cliffs, NJ: Prentice-Hall, 1982; 237 pages, 17.5 by 23.5 cm, hard- cover, ISBN 0-13-963454-1, $17.95. ■ jooks received at BYTE Publications during this past month. Although the list is not meant to be exhaustive, its purpose is to acquaint BYTE readers with recently published titles in computer science and related fields. We regret that we cannot review or comment on all the books we receive; instead, this list is meant to be a monthly acknowledgment of these books and the publishers who sent them. 490 April 1982 © BYTE Publications Inc Event Queue April 1982 April Courses from George Wash- ington University, Hampton, VA; Salem, NH; Washington, DC; London, England; and Berlin, West Germany. Among the courses scheduled are "Voice Input /Output," "Microwave Systems Plan- ning," "Writing Professional and Technical Communica- tions," and "Computer Graphics Systems: Design and Applications." For further in- formation, contact Continu- ing Engineering Education, School of Engineering and Applied Science, George Washington University, Washington, DC 20052, (800) 424-9773; in the District of Columbia, (202) 676-6106. April C ourses in Structured Sys- tems, various sites through- out the U.S. Courses in "Structured Systems Design," "Structured Requirements De- finition," and "Management Overview of Data Structured Systems Development" are being offered by Ken Orr and Associates. For information on meeting times, places, and fees, contact Ken Orr and As- sociates Inc., 715 East 8th, Topeka, KS 66607, (800) 255-2459; in Kansas, (913) 233-2349. April Fundamentals of Data Pro- cessing for Administrative As- sistants and Office Support Staff, various sites throughout the U.S. The American Man- agement Associations (AMA) has designed this three-day course for secretaries, assis- tants, supervisors, and other personnel desiring to learn the fundamentals of data process- ing and its use in offices. Computer hardware, soft- ware, programming lan- guages, and technology will all be covered. The team fee for AMA members is $470 per individual and $550 for non- members. Individual fees are $550 for AMA members and $630 for nonmembers. For a schedule of dates and loca- tions, contact the AMA, 135 West 50th St., New York, NY 10020, (212) 586-8100. To reg- ister by phone, call (212) 246-0800. April Knowledge Engineering in the 1980s, Boston, MA. Expert Systems are computer pro- grams that reason in tasks that require considerable human expertise, such as locating computer malfunctions, mon- itoring intensive care patients, analyzing noisy signal data, and diagnosing medical prob- lems. This one-day executive briefing provides an introduc- tion to the potential benefits and costs of Expert Systems. For further information, con- tact Dina Barr, Teknowledge, 151 University Ave., Palo Alto, CA 94301, (415) 326-6827. April-May C ourses from Boeing Com- puter Services, various sites throughout the U.S. Boeing Computer Services is offering a wide variety of computer- related courses at its regional service centers. Course topics range from "Introduction to Data Processing" to "Struc- tured Program Development in FORTRAN." For a com- plete schedule of times, loca- tions, and fees, contact Boeing Computer Services Co., Edu- cation and Training Division, POB 24346, Seattle, WA 98124, (206) 575-7700. April-May Seminars and Conferences from Datapro Research, vari- ous sites throughout the U.S. Among the topics to be pre- Circle 175 on inquiry card. START YOUR OWN COMPUTER CO. HOW TO START YOUR OWN SYSTEMS HOUSE $36. 7th edition, November 1981 Written by the founder of a successful systems house, this fact-filled 220-page manual covers virtually all aspects of starting and operating a small systems com- pany. It is abundant with useful, real-life samples' contracts, proposals, agree- ments and a complete business plan are included in full, and may be used im- mediately by the reader. Proven, field-tested solutions to the many problems facing small turnkey vendors are presented. HOW TO BECOME A SUCCESSFUL COMPUTER CONSULTANT $28. by Leslie Nelson, 4th revised edition, December 1981 Independent consultants are becoming a vitally important factor in the micro- computer field, filling the gap between the computer vendors and commercial/ industrial users. The rewards of the consultant can be high: freedom, more satis- fying work and doubled or tripled income. This manual provides comprehensive background information and step-by-step directions for those interested to ex- plore this lucrative field. FREE-LANCE SOFTWARE MARKETING $30. by B.J. Korites, 3rd edition, June 1980 Writing and selling computer programs as an independent is a business where • you can get started quickly, with little capital investment • you can do it full time or part time • the potential profits are almost limitless. This best-seller by Dr Korites explains how to do it. HOW TO START YOUR OWN WORD PROCESSING SERVICE $39.50 by Leslie Nelson, February 1982 Turn a small investment into a steady, money making business that adds $10,000, $50,000 or $100,000 to your income. Detailed start-up, marketing and operations plans are included. Send check, money order, VISA, Master Charge or American Express # and exp. date. Publisher pays 4th class shipping. Add $1.00 per book for UPS shipping (USA only), NJ residents add 5% sales tax. For faster shipment on credit card orders call (201) 783-6940. ESSEX PUBLISHING CO. Dept 2 285 Bloomfield Avenue • Caldwell, N.J. 07006 Supercharge Your Micro's Performance With The Professional Operating System with CP/M™ Compatability •Spectacular Performance. Programs run 3 to 10 times faster compared with TRSD0S or CP/M. Benchmark results up to 20 times faster obtained with some applications by independent firm' • Doubla-Sidfld Drive Support. Provides 1 25 Megabytes of storage per 8' double-sided/density disk Intermix any combination of single- or double-sided drives on-line •Expanded Directories. Store larger number of files and more information per disk. •Automatic D«rulty/Sld« Recognition. Detects changes in disk format automatically Change disks at any time without compromising data or "BDOS/Rfiad-Only" errors •Fast Disk Backups. Copy a complete 8" SS/DO diskette (610K) in less than 80 seconds Copy a douDie sided/density diskette (1 25 Megabytes) in less than 1 minute 45 seconds 1 •Hard Disk Drive Support. Supports large hard disks in excess of 1,000 Megabytes without partitioning. •Advanced Utilities. Complete set ot disk utilities, system. date and lime functions, communications channel interface, etc provided as standard features •Enhanced Automatic Print Spooling. Run multiple printers simultaneously; support for multiple queues and printers is standard feature on spooling versions •CP/M CompatlbHtty. Virtually any CP/M (version 2.x) program will run under TURB0D0S without modification Also fully media compatible with standard CP/M-format diskettes •Advanced Milnframe-IIke features. Includes read-after-wnte validation of all disk update operations, type-ahead buffers, incremental disk backup utility, password/log-on security, system date and time functions, accepts string of multiple commands, and numerous other capabilities not available under CP/M or TRS00S Multi-user, networking versions also available TRS"80 ModGl II of* *& ^W P" Dealer and OEM inquiries invited and Xerox 820 versions Special Introductory Price 'king versions also available *195i Data-Rx,lnc. Easily adaptable to any 280-based computer. (408) 375-2775 •686 Lighthouse Avenue* Monterey, 93940 TURB0D0S is the registered trademark of Software 2000 CP/M. MP/M, and CP/NET are registered trademarks ol Digital Research Circle 135 on inquiry card. April 1982 © BYTE Publications Inc 491 Circle 107 on inquiry card. / \ Presenting a C Compiler for CP/M-86 and IBM® PC-DOS® That Speaks Your Language! The C86™ Compiler offers the most up-to-date language available, especially designed for CP/M-86™. Special features include the C language pre- processor, externals, statics, data initialization, pointers, arrays, structures, longs and floats. You can't beat the convenience, dependability and affordability of the C86™ compiler, and with no assembly step required, it's faster than you ever imagined! The C86™ system includes a linking loader, librarian and a large support library. All library source code is included, so that you may extend or modify the library. You may combine code written in C with code written using ASM-86™. IBM ® personal version available soon. For more information write or call. Dealer inquiries invited. *150 Disk and Documentation. $ 25 Documentation only. $ 20 Overseas Airmail. Computer Innovations, Inc. 75 Pine Street Lincroft, New Jersey 07738 Telephone: (201) 530-0995 C86 is a trademark of Computer Innovations, Inc.; CP/M-86 and ASM-86 are trademarks of Digital Research; IBM and PC-DOS are registered trademarks of International Business Machines, Inc.. :■■;.: ij-fc-.;-. _____ __> ______ ..jmat . ^H_^ : LEAPAC 2D and 3D GRAPHICS SOFTWARE (DRIVERS for moat Rlottlnfl Devlcea) CALL or WRITE LEAPAC SERVICES 8245 Mediterranean Way Sacramento CA 95826 (918) 381-1717 Event Queue, sented are 'IBM's Systems Network Architecture/' "Data Dictionary /Directory Sys- tems/' and "Data Processing: Fundamental Concepts," En- rollment fees are $640 for Datapro subscribers and $690 for nonsubscribers. For a complete catalog with descrip- tions, dates, and locations, contact Datapro Research Corp., 1805 Underwood Blvd., Delran, NJ 08075, (800) 257-9406; in New Jersey, (609) 764-0100. April-June Courses and Seminars from Sira Institute, various sites throughout England. Sira In- stitute is sponsoring seminars on a wide variety of subjects, ranging from microprocessor familiarization to design and development of microproces- sor-based equipment. For de- tails, contact Conferences & Courses Unit, Sira Institute Ltd., South Hill, Chislehurst, Kent BR7 5EH, England. April-June Datamation Institute Semi- nars on Information Manage- ment, various sites through- out the U.S. Databases and communications, systems per- formance, data-processing management, word process- ing, office automation, com- puter graphics, and topics of general interest are among the areas to be covered by these two-day seminars. Fees range from $495 to $595. For sched- ules of times and places, con- tact Karen Smolens, the Cen- ter for Management Research, Datamation Institute Seminar Coordination Office, 850 Boylston St., Chestnut Hill, MA 02167, (617) 738-5020. April-June Intensive Two-day Seminars for Professional Develop- ment, various sites through- out New England. Among the seminars to be offered by Worcester Polytechnic In- stitute are "Fundamentals of Data Processing, " "Distri- buted Systems: The Architec- ture and Utilization of this Revolutionary Technology," and "Microprocessors: Hard- ware, Software, and Applica- tions." Registration fees range from $445 for a two-day pro- gram to $990 for a 7 N.VTT i 1 i 7\ r : — I — I — # SCIENTIFIC PLOTTER 48K APPLE II + , $25 Draws professional-looking graphs of your data. EASIER, FASTER, NEATER and more ACCURATE than handptotting. You choose data format, length and position of axes, 20 symbols, error bars, labels anywhere in 4 orientations, etc. Includes 5 DEMOS on disk with 30-PAGE MANUAL. CURVE FITTER 48K APPLE II +, $35 Selects the best curve to fit your data. SCALE, TRANSFORM, AVERAGE, SMOOTH, INTERPOLATE {3 types), LEAST SQUARES FIT (3 types), EVALUATE UNKNOWNS from fitted curve. Includes 5 DEMOS on disk with 33-PAGE MANUAL. VIDICHART 48K APPLE II + , $75 NEW tools for lab data management. FAST plots of 4 data sets with SCROLL- ING in 4 directions, ZOOM scaling on X and Y axes, 2 types of graphic CUR- SORS and on-screen STATUS REPORT, PLOTS A/D INPUT while sampling. ADD, SUBTRACT, MULTIPLY, DIVIDE, INTEGRATE, DIFFERENTIATE, AVERAGE or NORMALIZE data sets with SIMPLE COMMANDS. Ideal for spec- tra, chromatograms, rate curves, etc. Includes SAMPLE DATA on disk with 28-PAGE MANUAL. SPECIAL! All 3 programs on one disk, only $120. Since each program uses the same data format on disk, data may be shared. BUY THESE PROGRAMS AT YOUR LOCAL DEALER OR ORDER DIRECT. For more information, ask for FREE brochure or send $5 for any manual ($12 for all 3), deductible with purchase. Add $1.50 shipping on all orders. For fastest service, call in your VISA or Master Card order. INTERACTIVE MICROWARE, INC. P.O. Box 771, Dept. B State College, PA 16801 CALL (814) 238-8294 for IMMEDIATE ACTION llljl • Trademark of Apple Computer, Inc. Model EP-2A-87 EPROM Programmer The Model EP-2A-87 EPROM Programmer has an RS-232 compatible interface and in- cludes a 2K, 4K or 8K buffer. Seventeen RS-232 commands allow another computer to download or remotely control the Programmer. INTEL, TEXTRONIX OR MOTOROLA formats are supported. The buffer may be edited directly from a CRT and EPROMS can be copied off-line. Power re- quirements are 115v 50/60 Hertz at 15 watts. EP-2A-87-1 Programmer with 2K Buffer $575.00 EP-2A-87-2 Programmer with 4K Buffer $650.00 EP-2A-87-3 Programmer with 8K Buffer $725.00 Non-Standard voltage (220v,240v, or 100) $ 15.00 Personality Modules PM-0 PM-1 PM-2 TMS2708 $18.00 2708 18.00 2732 34.00 PM-2A 2732A 34.00 PM-3 TMS2716 26.00 PM-4 2532 34.00 PM-5 2716 18.00 SA-64-2 2564 39.00 PM-5E 2816 $36.00 PM-6 2704 18.00 PM-7 2758 18.00 PM-8 MCM68764 36.00 PM9 2764 36.00 PM-10 2564 36.00 SA-64-3 2764 39.00 Optimal Technology, Inc. Phone (804) 973-5482 Blue Wood 127 Earlysville, VA 22936 Circle 307 on inquiry card. April 1982 © BYTE Publications Inc 495 Circle 377 on inquiry card. c COMPARE COMPILERS New C/80 2.0 gives you all three: features, performance and price. Compiled Loaded Compile Program Size (with and Load Execute Compiler Size runtime Time Time Price (Bytes) support) (sees) (sees) C/80 2.0 313 3181 90 24.8 $ 49.95 Code Works CW/C 1 422 1835 146 53.3 $ 75 Aztec C 1 378 4657 139 33.0 $135 BDSC 1.44 ] 305 3696 54 44.0 $150 Super soft C 3 300 2500 92 26.0 $200 Tiny-c 2 Compiler 1 (4) (4) 96 930 $250 Whitesmith C2 290 7384 242 15.6 $750 Performance Comparison Using Benchmark Program Published in BYTE, September 1981 ^Our results on 4 MHz Zenith Z89 with 8" disks ^Results reprinted by permission from September 1981 BYTE ; ©BYTE Publications Inc 3 From information sheet provided by manufacturer ^Figures not available. The new C/80 compiler, Version 2.0, supports all C language features except float, long, typedef, bit fields, and arguments to macros. C/80 2.0 is available in disk formats for Heath/Zenith (HDOS & CP/M*). Osborne 1* and 8" standard CP/M systems. Price is $49,95; add $3 shipping ($2 for 5" disks); in CA add tax. Phone orders welcome. *CP/M is a registered trademark of Digital Research. Osborne 1 is a registered trademark of Osborne Computer Company C n\e SoftwSre ^ToolWdrkg 14478 Glorietta Drive Sherman Oaks, CA 91423 (213) 986-4885 VISA* Use reader service number for our catalog of over 20 software products. Dealer inquiries invited. STOCK ORDERS SHIPPED IN 24 HOURS ADDS VIEWPOINT ^TVVQTYI Tho leu Equipped Printer for th» Money! MODEL 8SG 68G FEATURES Graphics Standard Friction Feed Standard Adjustable Tractor Feed Standard Parallel interface Standard Serial interface Standard Data Buffer IK Standard Correspondence Font 11 x 7 Standard Print Speed . lOOCPS Number of Columns 80. 96. 132 Variable Forms Length Standard A in pi Ampi $649 DISC DRIVES QUME: DT-8...$525.00'.ty, 8" DSDO 48 TPI TANDON: TM-1002...$335.00 V- 5%" DSOD 48 IIP TM-848-l...$475.00'«» r SSDD THINUNE TM-602...$995.00 tv 57*" 5MBYTE WINCHESTER DT-5...$310.00'«*. Sfc" DSDD 48 TPI TM-100-4.„$425.00' a T Y1 5fc ' DSOD 96 TPI TM-848-2...$550.00V, r DSDD THINUNE TM-603...$1175.00'«y,. ST*" lOMBYTE WINCHESTER QUME LETTER QUALITY PRINTERS SPRINT 9/45 $2245' OIHEH MODEl AND CONf IGOR AT IONS AVAIU^BLE (408) 438-5454 Ma I SCOnS VALLEY DR., SCOTTS VALLEY, CA 95066 TERMS: Cashiers Check, VISA, M/C, COO Shipping charges added to all orders * Quantity Discounts Available /MEDIk DISTRIBUTING Event Queue . other testing methods. The fee is $675. Contact Dr. Dimitri Kececioglu, Institute Director, Aerospace and Mechanical Engineering Dept., Building 16, University of Arizona, Tucson, A2 85721, (602) 626-2495. April 20-22 D-COM, Hynes Auditorium, Boston, MA. D-COM will bring DEC (Digital Equipment Corporation) vendors to- gether with DEC users. For in- formation, contact Ron Davies, D-COM Inc., 7312 Burdette Court, Bethesda, MD 20817, (301) 469-7650. April 20-23 The Fourth International Con- ference on Video and Data Recording, University of Southampton, Southampton, England. This conference is designed for engineers and physicists. Papers, group ses- sions, and a trade exhibition will be featured. Among the topics to be addressed are 'Magnetic and Other Record- ing Media," "Theory of Recording Processes," and "Coding, Modulation, and Signal Processing." Highlight- ing this conference will be a forum on digital standards. For further information, con- tact the Conference Registrar, Institution of Electronic and Radio Engineers, 99 Gower St., London, WC1E 6AZ, England, Tel: 01-388-3071. April 20-23 VIO-Voice Input/Output for Computers, Boston, MA. This four-day course is de- signed for product develop- ment and design engineers, systems analysts, program- mers, and technical managers involved in the planning, de- sign, and implementation of voice input/ output systems. The topics to be covered in- clude voice-processing algo- rithms and software, evaluat- ing VIO hardware compo- nents and systems, utilizing speech -synthesis techniques, and designing voice-recogni- tion techniques. Participants will have the opportunity to work with devices that permit online generation of computer voice output, data entry by means of voice input, and voice input for system con- trol. The course fee is $795; on-site courses can be ar- ranged. For information, con- tact Ruth Dordick, Integrated Computer Systems, 3304 Pico Blvd., POB 5339, Santa Monica, CA 90405, (800) 421-8166; in California, (800) 352-8251. April 21-28 Hanover Fair '82, Hanover, West Germany. The annual Hanover Fair is one of the world's largest industrial trade exhibitions. More than 330 American firms are expected to exhibit products, services, and technology at the Fair. Contact M. A. Delia, Han- over Fairs Information Cen- ter, POB 338, Whitehouse, NJ 08888, (800) 526-5978; in New Jersey, (201) 534-9044. April 22 California Computer Show, Hyatt Hotel, Palo Alto, CA. This show is for original equipment manufacturers, knowledgeable users, distribu- tors, and dealers. More than 60 computer manufacturers will be exhibiting mainframes, mini- and microcomputers, and peripherals. Contact Carol Reimer, Norm De Nardi Enterprises, 289 South San Antonio Rd. #204, Los Altos, CA 94022, (415) 941-8440. April 22-25 New York Computer Show and Office Equipment Exposi- tion, Nassau Coliseum, Uniondale, NY. For details, see April 15-18. April 23-25 The 1982 Computer Showcase Expo, Miami, FL. For details, see April 15-17. 496 April 1982 © BYTE Publications Inc Circle 251 on Inquiry card. Circle 405 on inquiry card. April 24 Computer Swap America, Santa Clara County Fair Grounds, San Jose, CA. This high-technology flea market features everything from flop- py disks to home satellite-re- ceiving stations. Admission is $3. Contact Computer Swap America, POB 52, Palo Alto, CA 94302, (415) 494-6862. April 25-30 DP Training Managers' Workshop, Washington, DC. This workshop is intended for individuals with less than 18 months' experience in coordi- nating data-processing train- ing programs. Participants will learn to establish in-house education programs that will meet management objectives and ensure a high return on their organizations' invest- ment in training. The registra- tion fee is $850. Contact Linda Hubacek, Deltak Inc., 1220 Kensington Rd., Oak Brook, IL 60521, (312) 920-0700. April 27-30 Digital Filters and Spectral Analysis, Washington, DC. For details, see April 13-16. April 27-28 The Eighth Annual National Computer Security and Pri- vacy Symposium: Top Secret '82, Washington, DC. Spon- sored by Honeywell, approxi- mately 22 national authorities on computer security and privacy will speak on a varie- ty of topics. Training work- shops in security planning and risk analysis, disaster recovery and contingency planning, and computer fraud investiga- tion will be held. The fee for the symposium is $525; dis- counts on multiple registra- tions are available. Contact the Security Symposium Reg- istrar, Honeywell Inc., M/S T-99-4, POB 6000, Phoenix, AZ 85005; or call Jerome Lobel, (602) 249-5370. April 28-May 1 The Third Annual Conference of the Educational Computing Organization of Ontario, On- tario Institute for Studies in Education (OISE), Toronto, Ontario, Canada. This con- ference is designed for educa- tors at all levels. Exhibits will be featured. Contact OISE, 252 Bloor St. W, Toronto, Ontario M5S 1V6, (416) 923-6641, for additional details. April 29-30 An Assessment and Forecast of Computer Graphics, Rye Town Hilton, Port Chester, NY. This conference will assess the present state of computer graphics and will evaluate hardware, software, systems services, and applica- tions. The role of graphics in today's business environment will be considered and factors affecting market growth will be analyzed. Leaders in the in- dustry will present and ex- change views with attendees. For further information, con- tact Carol Sapchin, Frost & Sullivan Inc., 106 Fulton St., New York, NY 10038, (212) 233-1080. May 1982 May-June Sensors & Systems '82, vari- ous sites throughout the cen- tral and western regions of the U.S. This series of three-day conferences will cover all aspects of sensor technology from temperature sensors through to displacement, ve- locity, acceleration, magnetic field, and moisture. Other topics to be covered include signal conditioning, digital in- terfaces, and system inter- faces. Contact Network Ex- hibitions, 785 Harriet Ave., Campbell, CA 95008, (408) 370-1661. New from Tarbell • . . 4 SERIAL/2 PARALLEL BOARD S- 100 Compatible Tarbell Electronics introduces afour-serial/two-parallel port board. The four RS-232 serial input/output ports utilize four 8251 's and eight consecutive 8080 ports. Features include full handshaking capability and four separate dip-switch controlled baud-rate generators. Support is provided by Tarbell's XIOS for the Digital Research MP/M-II. Two eight-bit parallel I/O ports include four eight-bit latches (74LS373's) and use four consecutive 8080 ports. There are separate handshaking lines, outputs that will drive up to 30 ma and inputs with less than .4 ma load. This new board is S-100 compatible and is capable of creating interrupts for the Tarbell CPU. All cables are included; the board comes completely assembled and thoroughly tested with a six- month no-fault full warranty. 950 DOVLEN PLACE • SUITE B CARSON, CA90746« (213) 538-4251 Journal of Pascal and Ada ™ It is the most up-to-date resource on Pascal and Ada software and hardware including: •New Developments •Algorithams •In-Depth Reports on Products •Tutorials -Relevant Topics •Application Software For: — Businesss — Graphics — Statistical — Scientific — System — Educational •Book Reviews ^Software Reviews "A help in any one area is worth the price. " No-Risk Trial Subscription Offer 1 Year (6 Issues) $14.00 in U.S.A., $21.00 Elsewhere —Refund on Unused Portion— r t D VISA I □ MasterCard » □ American Express Card No. . Signature Name Exp. Date Street . City __ State Zip„ Mail to: Journal of Pascal and Ada P.O. Box 327 Payson, Utah 84651 TM -Trade Mark of Department of Defense Circle 227 on inquiry card. April 1982 © BYTE Publications Inc 497 Circle 14 on inquiry card. QUALITY parts at DISCOUNT PRICES 4PDT PRIHTED CIRCUIT 12 VDC 14 pin style 3 amp contacts BRAND NEW PC Mount $2.75 EA. SPECIAL 1000 MFD Mfer=£? 25 VOLT 2 FOR $1.00 COMPUTER GRADE CAPACITOR 1 700 mfd. 150 VDC $2. 2 1/2" DIA X 4 3/V HI 3,600 mfd. 40VDC S1.00 SUPER SMALL PHOTO FLASH 170_MFD 330 VOlT 1 1/4 "X 7/ B " 2 for $1.50 10 for $7.00 RFI/EMI FILTER FOR NOISE SUPPRESSION C/D# APF5t+0W RATED: 5 AMPS 250 VAC S3. 50 each JOYSTICK PRECISION DEVICE... CONTAINS 4 50K CENTER TAPPED ALPS POTS $ 4. 75 each* \ c v^MRF 901 * ? ^V£? MICROWAVE TRANSISTOR $2.50 EA. ■ *, SEND FOR NEW 1982 .< 3 e ®/ 40 PAGE CATALOG f«® e 6,400 mfd. 60 VDC $2. 1 3/3*u.a X 4 1 1 2,000 mfd. 40 VDC $3.00 $2.50 | 1/4* V ■* DIA X 4 1/V HIGH 18,000 mfd. 75 VDC S4.00 2 1/2" DIA X <4 l/2' r HIGH 20,000 mfd. 25VDC 2 " DIA. X 2% u HIGH $2.00 22,000 mfd. 15 VDC 2" o.a X 2 I/2*hk.h $2.00 22,000 mfd. 40 VDC ' DIA. X 6" HIGH $3-00 25,000mfd.75 VDC $4.50 DIA X 4 5/8" HIGH 4S 000 mfd. 25 VDC $3 50 72,000 mfd. 15 VDC L.E. D. s | STANDARD JUMBO # DIFFUSED RED 10 FOR $1,501 I GREEN 10 FOR $2.00 YELLOW 10 FOR $2,00 FLASHER LED ff\ - 5 VOLT OPERATION JUMBO SIZE [f 2 FOR $1.70 Bl POLAR LED 2 FOR $1.70 SUB MINI LED g ,079" X .098" 20mA at 1.75v 10 FOR $1.00 200 FOR $18.00 QUANTITY PRICES AVAILABLE t 14 CONDUCTOR RIBBON CABLE ALL CLCCTROflKS CORP. 905 S. Vermont Ave. jem*s PO BOX 20406 • Quantities Limited Los Angeles, Calif. 90006 ; ^ J r f 5 * 10 00 (213) 380-8000 shipping us a - Calif. Res. Add 6% Mon. - Fri. Saturday ■ pfwn P' shipping 9 AM 5 PM 10 AM -3 PM 3D % SCOTCHFLEX #3565 28 AWG STRANDED GRAY WITH RED MARKER 10 FEET for $2.50 100 FOOT ROLL $1200 TRANSFORMERS 120 volt primaries 6 VOLTS at 1S0 mA $1.25 12 V.C.T. at 500mA $2.50 16 5 V. at 3 AMPS $650 18 VOLTS at 1 AMP $4.50 25.2 VCT at 28 AMP $5.50 FLAT LEVER MINI-TOGGLE S.RDT (ON-ON) J 5 AMP £ 120 VAC A CSK * 7105 1 $1.00 EACH fj§ 10 for $8.50 Ff 100 for $7500 * (213) 891-5705 Complete product line for Apple, NEC, S-100, IBM. Low Prices, high quality, and fast delivery. Apple: Add-on Mini-floppy . $375 Apple: 5 M Byte Hard Disk System . $2250 Appic: 128K RAM Card .$700 Apple: Double-density 8" Floppy Controller . . $400 IBM: Add-on Mini-floppy . $275 S-100: 64K Low Power Static RAM Card . . $475 S-100: Sierra Data SBC, 4MHz Master $825 NEC PC-8000 System. , New Low Prices Epson MX- 100. .$685 ADDS Viewpoint -Green. . $545 TandonThinline8"- Double Sided. $510 5 X A" Diskettes . 'BoxoflO All items new. guaranteed. On-site service center. Ii e claim lu have more satisfied customers per square inch of ad space i/iati any other By 'le advertiser. - . Mail: P.O. Box Q, Sherman Oaks, CA 91423 Store: 16709 Roseoe Blvd., Sep ulveda, CA 91343 (213)891-5705 Event Queue, May 2-7 DP Training Managers' Workshop, Chicago, IL. For details, see April 25-30. May 6-9 The Southern California Computer Show & Office Equipment Exposition, Los Angeles Convention Center, Los Angeles, CA. For details, see April 15-18. May 7-9 The 1982 Computer Showcase Expo, Anaheim, CA. For de- tails, see April 15-17. May 10-12 Dexpo 82, Marriott Hotel, Atlanta, GA. This exposition features DEC- (Digital Equip- ment Corporation) compati- ble hardware, software, and services. Contact Expoconsul International Inc., 19 Yeger Rd., Cranbury, NJ 08512, (609) 799-1661. May 10-13 The Annual Meeting and Technical Conference of the IEEE Industrial Power Sys- tems Department, Marriott Hotel, Philadelphia, PA. For details, contact Dr. Paul Reece, General Electric Co., 6901 Elmwood Ave., Mail Drop 06302, Philadelphia, PA 19142, (215) 726-2800. May 10-14 The Twentieth Annual Con- vention of the Association for Educational Data Systems (AEDS), Sheraton Twin Towers, Orlando, FL. This convention includes presenta- tions on the state of the art in educational computing. Ad- ministrative and instructional computing applications will be presented, and new ways of improving educational pro- cesses will be explored. Con- tact AEDS, 1201 Sixteenth St. NW, Washington, DC 20036, (202) 833-4100. May 12-14 The 1982 Camahan Con- ference on Security Tech- nology, Carnahan House Conference Center, Lexing- ton, KY. Among the topics to be addressed at this con- ference are 'Tederal Standards for Telecommunications Privacy and Security," "Secure Voice-Bandwidth Modem," and "Multistatic, Airbom Intruder Detection Radar." The registration fee is $325, which includes buffets, a banquet, and a copy of the proceedings. Contact Susan McWain, Office of Continu- ing Education, College of En- gineering, 223 Transportation Research Building, University of Kentucky, Lexington, KY 40506, (606) 257-3971. May 14-15 The Second Annual Southern California Computers-in-Edu- cation Conference, University High Scool, Irvine, CA. This conference covers the applica- tion of computers in educa- tion from kindergarten through two-year college. All areas of curriculum will be covered, including reading, mathematics, science, lan- guage, and special education. Hands-on workshops and field trips are planned. Con- tact Craig Walker, Arrow- view Intermediate School, 2299 North G St., San Bernar- dino, CA 92405, (714) 886-9118. May 24-26 Applefest /Boston, Hynes Auditorium, Boston, MA. This show will feature more than 200 displays and booths of Apple-compatible products and accessories. Seminars and panel discussions will be held. Ticket prices are $6 per day or $15 for a three-day pass. Con- tact National Computer Shows, 824 Boylston St., Chestnut Hill, MA 02167, (617) 739-2000. 498 April 1982 © BYTE Publications Inc Circle 54 on inquiry card. May 15-16 The North American Com- puter Othello Championship, Learning Resources Center, Andersen Hall, Northwestern University, Evanston, IL. This two-day tournament is spon- sored by the United States Othello Association. Cham- pions will be determined in three categories: microcom- puter systems (located on site), mainframe systems (tele- phone hookup), and special- purpose Othello machines. For complete tournament de- tails, write to Professor Peter W, Frey, Dept. of Psychol- ogy, Northwestern Univer- sity, Evanston, IL 60201. May 16-21 Advanced DP Training Man- agement Workshop, Los Angeles, CA. This workshop is intended for training man- agers directly responsible for planning, monitoring, and evaluating data-processing training and reporting to upper-level management. The prerequisite for this workshop is completion of Deltak's Training Managers' Work- shop (see April 25-30) and a minimum of one year's ex- perience since completion, or the equivalent on-the-job ex- perience. The registration fee is $850. Contact Linda Hubacek, Deltak Inc., 1220 Kensington Rd., Oak Brook, IL 60521, (312) 920-0700. May 16-19 The First Annual Convention & Exposition of the Electronic Funds Transfer Associa- tion — EFT Expo, Fairmont Hotel, Dallas, TX, This con- vention will feature addresses on a wide range of electronic funds transfer issues, includ- ing automated teller inter- change, changes in corporate network services, home finan- cial services alternatives, and security. A special forum on the role of electronic funds transfer in the future of finan- cial services deregulation will highlight the convention. An equipment exhibit will be fea- tured. For complete details, contact the Electronic Funds Transfer Association, Suite 800, 1029 Vermont Ave. NW, Washington, DC 20005, (202) 783-3555. May 18-20 Microcomputers — A New Tool for Foresters, Purdue University, West Lafayette, IN. Sponsored by Purdue University's Department of Forestry and Natural Re- sources and by the Inventory and Systems Analysis Work- ing Groups of the Society of American Foresters, this con- ference seeks to advance the professional forester's knowl- edge of microcomputers and their applications in forestry. Session themes include hard- ware and software considera- tions as well as information processing and forest-inven- tory systems. Contact John W. Moser Jr., Dept. of Forestry and Natural Re- sources, Purdue University, West Lafayette, IN 47907, (317) 494-3596. May 19-21 Computer Hong Kong 82, Regent Hotel, Hong Kong. This three-day program, which embraces the Fifth Hong Kong Computer Con- ference, will focus on the elec- tronic data-processing mar- ket. For further details, con- tact Kallman Associates, 5 Maple Court, Ridgewood, NJ 07450, (201) 652-7070. May 21-23 The 1982 Computer Showcase Expo, Boston, MA. For de- tails, see April 15-17. May 22 The Third Annual New Jersey Microcomputer Show & Flea Market, Holiday Inn (North), Newark International Air- port, Newark, NJ, This event will feature more than 50 commercial exhibitors and 150 TANTALUM CAPACITORS I SBUFJSV S .*■ 1UF35V 5.* 2 2UF 20V 5* LINEAR CIRCUITS 47UF20V ssuf iov 120UF 6V ■4 PIN HEADERS PIN HEAOEHS 0PINEPGEBOAHDC0NN 6PPNEDGEBOAROCONN. OPIN RIGHT ANGLE CONN RS232 CONNECTORS DB2SPmate 52.75 OB 25S female 3.75 HOODS 1.50 UART's AY5-1013 - 3.75 TR16026 - 3.95 PT1482B - 3,25 M8868A - 8.95 COM2017 - 3.75 LM201 - LM301 '7 741CV - LM307 - LM308 - LM334 LM339 LF351 - LF353 - LF366 - LF356 - LM318 LM34S - I.M35B LM361 LM377 LM3FJG LM382 LM383 - LM386 - LM387 - CA758 1 ffl CA3018 1 96 CAX78 1 50 CA3060 - 96 CA3086 - 95 CA3140 1 2(1 LM2301 - 95 W88GC ■■*■ N5596A - 1 50 TL062 CP 96 TL064 CN - 1 5C INTERFACE & DRIVERS FD1791 .34.96 8130 2 50 8834.2 00 8T380 2 00 1488 90 8830 2.50 B837 2.00 MM5321 9 50 ■" 8833 2 50 8838 2 00 MM53jg CPU'S & SUPPORT CHIPS! 2.000 18.432 20.000 $4.25 ea. TOGGLE SWITCHES 10SO - SPOT 1. 10 2060 - DPDT 3.000 5.000 8.000 3.579 6.000 10.000 4000 6.144 18000 REGULATORS LM337 $2.50 79HGKC-5Va!5A $6.95 123 80 78M05 S .35 78L05 S .45 LM305G $ .75 320T5.12,15or24 S 90 340K-12, 15or24V$J.50 340T-5, 6. 8. 9, 12, 15. 18o(24V. $ .85 LAS1412 4 12V3AS3.95 74LS SERIES 26 4077 - 35. 20 4081 ■ 4082 .20 77. 4093 .60 N 4099 - 1 75 4', 4601 - .95 I: 4610 - .65 X - .65 70 4814 - 1.40 se 4515 MS - .75 ss 4618 1.26 » 4520 70 <*: 4553 7 7S H: 74C0O 27 45 74C02 27 70 74C08 a 74C10 27 H: 74C14 120 X 74C20 71 m 74C32 45 .25 74C73 .76 .40 74C74 50 AMD 2901 8202 B212 8214 8216 8224 MM5307 8264 14164-2) 2114L3 4nt3 4116-2 211023 TMS 3409 MK4027 3 26104-4 MK4008P 1M7001 8.95 - 35.X - 225 3.60 2.90 3 25 995 Is - 10.95 8228 A V 8259 - 6.95 8257 1AM9517)- 7.95 Z80ACPU - eoo Z8OAS10 - 12.95 8275 - 16.95 6845 • - 16.95 ROM's 2708 2716 . 5V 2732 1702A 2532 2732 82S23 82S112 826115 82S123 82S129 82S130 82S13I 82S181 3628A3 AM9218C 8256-5 (74188AI 74C76 74C83 74C85 74CS6 74C160 74C161 74C163 74C165 74C173 . 74C174 74C176 74C192 74C901 THIS MONTHS SPECIALS 8080A - $3.75 Z80ACPU - 6 00 8264 1 4 164-2 1 64K RAM $10.95 TMS9927NL controller $9,95 8275 CRT CONTROLLER - 16.95 4116-2 - 186 2114L $1.65 FD1791 B - 34.95 2732 32KR0M - 14.95 GOOD THRU APR 1982 74LSO0 • 74LS01 - 74LS02 - 74LS03 - 74LS04 - 74LS05 - 74LS08 - 74LS10 - 74LS11 - 74LS12 - 74LS13 - 74LS14 - 74LS15 - 74LS20 - 74LS21 - MLS22 74LS26 - 74LS27 74LS28 - 74LS30 - 74LS32 74LS37 - 74LS38 - 74LS40 74LS42 74LS47 - 74LS51 - 741 Sft 74US73 - 74LS74 - 74LS75 74LS76 - 74LS83 - 74LS8S - 74LS86 74LS90 - .22 ' 7*1510 7 22 MLS 109 .22 74LS112 22 74LSH3 20 74LS114 - 22 74LS123 - 20 74LS124- .22 74LS12S - 22 74LS126 45 MLS 132 40. 74LSI36 » .;. .■ « IS ■■i.-, : (" 18 74LSI51 25 74LS153 - 35 74LS155 - 28 74LS156 - 45 74LS157 18 ! 74LS158 - 35 | 741. 5 160 - 30 74LS161 30 74LS162 40 741 S 163 •44 I 74LS164 65 | 74LS165 20 74LS166 - 20 74LS169 - 35 74LS170 35 74LS173 35 74LS174 45 74LS175 76 74LS181 - ® 74LS190 - 40 74LS191 39 74LS192 - 45 74LS193 74LS196 74LS197 74LS221 45 74LS240 55 74LS241 - 59 741 S242 '■» I 74LS243 45 ML S344 45 J4LS245 50 74LS247 45 . 74LS24B - 48 ' 74L5251 *8 74LS253 *> ' 74LS257 40 74LS25R 60 74LS259 - 70 74LS266 48 74LS273 48 74LS279 - .75 741S280 58 74LS2S3 70 74LS290 58 74LS365 58 1 74LS366- 75 74ES367 1 10 74LS368 ' 75 74LS373 - 1 5° 74LS374 - 58 74LS377 - 45 74LS386 40 74LS390 196 74LS393 72 74LS670 .72 81LS97 .65 8ILS9S 60 8T26- POSTAGE RATES TERMS FOB CAMBRIDGE. MASS. SEND CHECK SEND $ 25 FOR OUR CATALOG OR MONEY ORDER MINIMUM TELEPHONE. FEATURING TRANSISTORS & C.O.D. PURCHASE ORDER OR CHARGE $20.00 RECTIFIERS 146 HAMPSHIRE MINIMUM MAIL ORDER $5.00. ST., CAMBRIDGE, MASS. 02139 SOLID STATE SALES P.O. BOX 74 B SOMERVILLE, MASS. 02143 TEL (617) 547-7053 toll free 1-800-343-5230 HAVE YOUR CAKE AND EAT IT TOO ITS A PIECE OF CAKE TO CONNECT AN fl cteK TRIX I INTERFACE TO YOUR OLIVETTI PRAXIS 30 OR 35 CORRECTING ELECTRONIC TYPEWRITER. DAISY WHEEL QUALITY AT DOT MATRIX PRICES! • 10+ CPS • 15 MINUTE INSTALLATION • HALF SPACE JUSTIFICATION • CABLE REMOVES IN SECONDS • TYPEWRITER FUNCT. UNIMPAIRED • AVAILABLE NOW: ATARI & APPLE • OTHER DIRECT CONNECTIONS AND RS232 AVAILABLE SOON ft ctex • PRINT AND PRINT #N OPERATE • NO INTERFACE NEEDED: USES FRONT CONNECTOR -ATARI USES CONTROLLER PLUG -APPLE • PRICE: $215- APPLE ADD $10 fBASED ON WARDS PR30 PRICE • TYPEWRITER AND SERVICE WIDELY AVAILABLE 12225 SW2nd/SGlTE200-B P.OB. CCC BEAVERTON, OR 97075 Circle 8 on inquiry card. April 1982 © BYTE Publications Inc 499 Circle 190 on Inquiry card, i The gnosis version ol P-LISP has been acknowledged- as the finest and most complete available tor Apple micro- computers, and, with the addi- tion of floating point math and HI-RES graphics, it becomes an indispensable tool for edu- cators, scientists, business ex- ecutives, mathematicians, or applications requiring artificial intelligence. This excellent pro- gram is now available for only S199 95(DOS 3 3 only) Included in an attractive binder is a ninety page user's manual which will aid you in creating your P-LISP programs. This manual is also available separately for S20.00. which is fully refundable on purchase of the program P-LISP will run on a 48K or larger APPLE II/IN . and will take advantage of ALL avai: for the Apple II able memory Supplied with the interpreter are several sample programs including a complete ELIZA. For those of you who do not fully understand P-LISP we have available the P-LISP Tutorial lor S25 00 This expertly written text is bound m a handsome binder and is packaged to include a disk containing all the sample programs referenced in the text at no extra charge X & Applesoft m BOM formerly Pegasys Systems, Inc. 4005 Chestnut Street—Philadelphia, PA 19104 Orders Only: 800 523-0725— Penna. Residents: 215-387-1500 Pennsylvania residents add 6V sales tax Apple is a trademark of Apple Computer Inc Event Queue. flea market sellers. Hardware, software, and accessories for all popular systems will be featured. Contact Kengore Corp., 3001 Rte. 27, Franklin Park, NJ 08823, (201) 297- 2526, for additional informa- tion. May 23-28 DP Training Managers' Workshop, Dallas, TX. For details, see April 25-30. June 1982 June 6-11 Advanced DP Training Man- agement Workshop, Calgary, Alberta, Canada. For details, see May 16-21. June 6-11 and June 20-25 DP Training Managers' Workshop, Philadelphia, PA, and Chicago, IL. For details, see April 25-30. June 13-16 The Fifteenth Annual Con- ference of the Association of Small Computer Users in Edu- cation, Chatham College, Pittsburgh, PA. This con- ference will include papers and demonstrations on the ed- ucational and administrative uses of computers. Other topics of interest are robotics, Pascal programming, com- puter literacy, and the use of packaged software in com- puter courses. For more infor- mation, contact Jan Carver, Computer Center, Chatham College, Pittsburgh, PA 15232, (412) 441-8200. June 15-17 The 1982 IEEE MTT-S Inter- national Microwave Sym- posium, Hyatt Regency Hotel, XCEL MICROCOMPUTER RETROFIT GRAPHICS 512 x 240 RESOLUTION FOR COMPUSTAR® SUPERBRAIN® TRS-80® MODEL II Z-89 HARDWARE RETROFIT from $895.00 SOFTWARE SUPPORT PROGRAMS •Symbol Generator ^| ^ $175.00 •Graph Plotter $175.00 •3D Generator $345.00 •Surface Plotter $395.00 •Graphics Terminal Emulator $395.00 •Screen Printer $65.00 ANADEX EPSON IDS fftO 1) 421-1423 IN CALIFORNIA CALL ysy. (213) 320-6604 ZnAMAXTEK.INC. 2908 Oregon Court, Torrance, CA 90503 Available in Europe from Micronex Ltd., Chew Magna, England 3042 (STD 027-589 3042) TRS-80-registered trademark Tandy Corp* Superbratrvtrademark Iniertec Data Syslems TekHonix- registered Irademark Tektronix Inc CPMrcgistered trademark Digital Research ^ A Message to our Subscribers From time to time we make the BYTE subscriber list available to other companies who wish to send our subscribers promotional material about their products. We take great care to screen these companies, choosing only those who are reputable, and whose products, services, or information we feel would be of interest to you. Direct mail is an efficient medium for presenting the latest personal computer goods and services to our subscribers. Many BYTE subscribers appreciate this controlled use of our mailing list, and look forward to finding information of interest to them in the mail. Used are our subscribers' names and addresses only (no other information we may have is ever given). While we believe the distribution of this information is of benefit to our subscribers, we firmly respect the wishes of any subscriber who does not want to receive such promotional literature. Should you wish to restrict the use of your name, simply send your request to BYTE Publications Inc, Attn: Circulation Department, 70 Main St, Peterborough NH 03458. Thank you. ^5= J) 500 April 1982 © BYTE Publications Inc Circle 456 on Inquiry card. INCREDIBLE? believe m in Washington Computer Services an affiliate o« iHSSSBSl «t. 1912 CUSTOM COMPUTER ROOM WIRING SINCE 1960 97 Spring Street, New York, New York 10012 TO ORDER: CALL OUR TOLL-FREE NUMBER: (800) 221-5416 In N.Y. State and for technical information: (212) 226-2121 HOURS: 9 AM-5:30 PM (EST) Monday- Friday TELEX: 12-5606 CABLE: WASHCOMP NYK from $995 $2799 PRINTERS 150 cps bidirectional - 9x9 dot matrix, quietized case, 136 col, vertical form control and many other functions wnu/^QRn We feel this printer offers nuw^uu the best price/ performance ratio available. RS-232 serial to 19,200 baud x-on, x-off add $25 f I3P Teletype 40, 300 LPM-typewriter quality, RS- from Only 232 interface. This quality printer is available in many $3200 configurations including forms access, quietized case, etc. Teletype 43 Teletype AP-200, 340 cps dot matrix (similar to Data Prod . M-200) NEC Spinwriter-55 cps, bidirectional, letter quality R. 0.7710 $2560 KSR7720 DIABLO 630-40 cps, bidirectional, daisy wheel, plot/graph QU ME Sprint 9/45 cps, daisy wheel C. ITOH Starwriter, 25 cps, daisy wheel, parallel C. ITOH Starwriter, 45 cps, daisy wheel, serial EPSON MX-80, 1 00, 80 cps, 9x9 dot matrix ANADEX 9500/9501 , up to 200 cps, high resolution dot OKIDATA Microline 80, 80 cps, 9x7 dot matrix Microline 82A, bidirectional, friction/ pin feed Microline 83A, bidirectional, 120 cps, uses 15 TI-810, 150 cps, Basic Packaqe-Compressed print, vertical form control MANNESMANN MT 1705 200 cps, 7x9, 132 col TALLY MT 1805 200 cps, 7x9 + NLQ 40x18 matrix CENTRONICS 739 100 cps, nx9 dot matrix, Full Graphics DEC LA-34 IDS PRISM, 132 col ' paper , color S-100 SPECIALTIES LE2L 68000 16 bit multi-user UNIX V. 7 $2799 $2349 $2228 $1500 $1680 $CALL $1325 $399 $525 $799 $1449 $1630 $CALL SCALL SCALL $567 $1085 $1785 d^ rrER 8086 16 bit, 128K RAM , Syst. #2 Group Call us for best prices on these high SCALL $3499 quality 2nd 2200 2065C 281 OA 2422A generation boards and systems. California Tnese n '9 n quality, reliable products have made CCS Computer defacto industry standard for S-100 products Systems Assembled and tested: list only H.D. Mainframe, 20a. P.S., 12 slot MB $434 $359 64 K dynamic RAM /Bank Select $720 $580 Z-80 CPU, serial port, ROM monitor $310 $259 Floppy Cont, CP/M 2,2, ROM monitor $425 $345 8000 SX, multi-user, multi-processor, turbo DOS $CALL CPM 2.2. FULL 2 YEAR WARRANTY! filSSOOflfr 1 We of * er 9 enerous disc ounts on the Compupro line of ^eLktronks^IJstm^ 5 ^ quality 8 and 16 bit boards ADVANTAGE SCALL & HORIZON SCALL INTERNATIONAL ISkxthStar* NEC Low prices on PC-8000 series Similar savings on the full lines of CCS, SSM, NNC, MORROW, DELTA, NORTHSTAR, ITHACA INTERSYSTEMS, GODBOUT, NEC, TELEVIDEO, IMS ZENITH, ADDS, DEC, DATA GEN., ATARI, DYNABYTE, TECMAR, DUAL 8" DISK DRIVE SALE 8"SHUGARTSA801R $450 8"SHUGARTSA851R $669 2for$1289 QUMEDATATRACK8 $589 2for$1110 VISTA industrial grade enclosure for 2 drives with P. S. $420 MORROW Discus 2D + CP/ M®, MICROSOFT BASIC, CONT. $950 Discus 2 + 2 + CP/ M®, MICROSOFT BASIC, CONT. $1195 Enclosure, power supply for 2 8" drives A & T $350 HARD DISK SPECIALS List om y CORVUS 10MB and controller $5358 $CALL 20MB and controller $6450 $CALL Constellation Network Multiplexer and Mirror Video Tape Disk Backup MORROW 26MB + controller + CP/M 2.2®, M basic $4495 $3821 «Wo controller, CDC Hawk Drive (5 fix, 5 rem) $7995 $6795 controller, Western Dynex {5 fix, 5 rem) $5995 $5099 £W Winchester 5 1 A drives complete with case, cable, £HHr software, S-100 controller. Adapter avail, tor use with ^IXCOMP any Z-80 system. Cartridge drive controllers avail. V List 5MB APPLE 10MB xerox ALT OS I ~'" ; PRIAM 8" and 14 ACCOUNTING PLUS WORDSTAR $300 MBASIC80 $235 OEM discounts available! z-89 $2898 R.s. mod. it $3398 s-wo Winchester/tape subsystems avail. DBASE II SUPERCALC $CALL $525 $221 FULLY CONFIGURED BUSINESS SYSTEMS The following are some examples of the fully assembled and tested business and scientific computer systems which we offer. All include 64K bytes RAM, Z-80A, 4mh CPU. We offer a full line of quality, tested software. SCALL SCALL $1849 $4849 $6999 $6693 SCALL SCALL DDDteO'^ysteDDOSS fine computers Delta S-4500 10 User, Multi-Processor, 40 MB hard 17 MB tape CC 221 OAw/floppy controller, 1 serial port CCS 300-1 A w/ 1 .2 MB floppy drives, 2 serial , 2 parallel ports CCS 400-1 A w/ 10 MB hard disc, 2 serial, 2 parallel ports NNC 80W w/5MB floppy, 8.4 MB hard disc, (OASIS optional) ALTOS single and multi-user systems designs Decision! CP/M Microsoft Basic, UNIX YCDHY 820 Deskt °P computer-64K, 2 floppys. (CP/M avail.) AtKUA. List $2995 $CALL We offer multi-user networks by DELTA PRODUCTS, DISCOVERY, TELEVIDEO, MUSYS, IMS, DIGITAL MICROSYSTEMS TERMINALS pmmi modem $359 AMPEX DIALOGUE 30, 80, 81 SCALL TELEVIDEO 910 C (multi-terminal) $610 925C $795 950C $950 SOROC IQ120 $729 HAZELTINE ESPRIT $669 DECVT-100 $1575 Similar savings for our HAZELTINE and LEAR SIEGLER li nes LOOK HERE! AMPEX Call us for ALL your softwear needs Dialogue 80 Systems Houses, Educational Institutions, & Government Agencies Given Special Consideration ALL OF OUR PERIPHERALS CAN BE CONFIGURED FOR RADIO SHACK® MODEL II DEALER and INTERNATIONAL INQUIRIES WELCOME For fast delivery, send certified check, money order or call to arrange direct bank wire transfer. Personal or company checks require two to three weeks to clear. All prices are mail order only. Prices subject to change without notice; call for latest prices. Prices include 3% cash discount. N.Y. residents add sales tax. Qantex is a trademark of North Atlantic Industries, Inc. Radio Shack® is a trademark of the Tandy Corp. CP/M® is a trademark of Digital Research. All sales subject to our standard sale conditions (available on request). Circle 430 on inquiry card. BYTE April 1982 501 Event Queue. Dallas, TX. The theme of this symposium is 'Thirty Years of Microwaves," Papers and tutorials on a wide range of topics, including computer- aided design and measure- ment techniques, microwave Held and network theory, as well as satellite communica- tions/microwave systems, will be presented. Contact J. R. Griffin, Texas Instruments Inc., Mail Stop 3432, POB 405, Lewisville, TX 75067, (214) 462-5693. June 15-17 The Office Automation Show /Conference, Barbican Centre, London, England. For details on this show and con- ference, contact Clapp & Poliak International, 7315 Wisconsin Ave., Washington, DC 20014, (301) 657-3090. June 16-18 The Twentieth Annual Meet- ing of the Association for Computational Linguistics, University of Toronto, Toronto, Ontario, Canada. This meeting features papers on syntax, computational semantics, discourse analysis and speech acts, machine translation, as well as the mathematical and theoretical foundations of computational linguistics. For additional in- formation, contact Don Walker, Artificial Intelligence Center, SRI International, Menlo Park, CA 94025, (415) 859-3071. June 28-30 National Educational Com- puting Conference (NECC- 82), Radisson-Muehlebach Hotel, Kansas City, MO. This conference features papers, sessions, panel discussions, and exhibits of educational computing products. Among the topics to be addressed are "Computer Use in the Physical Sciences," "Computer Educa- tion for Teachers," and "Com- puter Science, Engineering, and Information Systems Edu- cation." For more informa- tion, contact E. Michael Staman, NECC-82 General Chairman, Computer Ser- vices, 305 Jesse Hall, Universi- ty of Missouri -Columbia, Columbia, MO 65211. ■ In order to gain optimal coverage of your organization's com- puter conferences, seminars, workshops, courses, etc, notice should reach our office at least three months in advance of the date of the event. Entries should be sent to: Event Queue, BYTE Publications, POB 372, Hancock NH 03449. Each month we publish the current contents of the queue for the month of the cover date and the two following calendar months. Thus a given event may appear as many as three times in this section if it is sent to us far enough in advance. General Software Main Offices: 9060 Arrowood Ct. Terre Haute, IN 47802 WE HONOR VISA and MASTERCHARGE TOLL FREE - Outside Indiana 1-800-457-0517 ORDER DESKS (812)299-2484 Best Selection Best Service Write for our famous CATALOG. Contains many items not in ad. Outside US add $10 plus addi- tional postage. Add $3.50 postage and handling per each item. Indiana residents add 4% sales tax. Allow 2 weeks on checks. COD ok. Prices subject to change without notice. All items subject to availability. ARTIFICIAL INTELLIGENCE Disk Manual with * Only Manual Dental (PAS-3) $849/40 Medical (PAS-3) $849/40 ASHTON-TATE *dBASEI! $575/50 BUSINESS PLANNING SYSTEMS Plan-80 269/30 BYROM SOFTWARE "BSTAM $149/15 *BSTMS $149/15 COMPUTER CONTROL *Fabs(B-Tree) $159/25 Ultrasort $159/25 CONDOR COMPUTER Condor II $549/50 Condor III . $899/50 DIGITAL RESEARCH CP/M 2.2 Intel MDS-800 $149/25 Northstar (Horizon) $149/25 Micropolis $169/25 TRS Model II . .$159/35 CB-80 $459/35 CBasic2 $ 98/20 ERIC COMPUTER 'Super vyx $ 89/15 FAIRCOM * Micro B + (Specify language) $229/20 FINANCIAL PLANNING 'Mini Model $449/50 FRIENDS ACCESS 80 I $249 ACCESS 80 II $429 FRONTIER SOFTWARE Professional Time Accounting . $549/40 General Subroutine $269/40 Application Utilities $439/40 ISA Spellguard $229/25 SP/Law .$109 PASCAL LANGUAGE Pascal Z $349/30 Pascal MT+ V5.5 $429/30 Compiler $316/20 SPPOnly $140/15 KEY BITS Wordsearch $1 79/50 String 80 $ 84/20 String 80 (Source) $279 String Bit $ 65 LEXISOFT •Spellbinder $349/45 MICRO AP Selector IV $269/35 Selector V $469/50 SBasic $269/25 MICRO TAX * Level I $249 * Level II $995 * Level III $749 *Comboli + l!l $1495 Microsoft 5.3 49 Run time module MICRO PRO Wordstar $309/60 WS Training Guide 20 WS Custom Notes $429/na MailMerge $109/25 WS-Mailmerge $419/85 Datastar $249/60 DS Custom Notes $429/na Calcstar $259/na Supersortl $199/40 Spellstar $175/40 MICROSOFT Basic-80 $298 Basic Compiler $329 Fortran-80 $349 Cobol-80 $629 M-Sort . .$124 Macro-80 $144 Edit-80 $ 84 MuSimp/muMath $224 MuLisp-80 , $174 NORTHWEST ANALYTICAL *Statpak $439/40 OASIS •"The Word" $ 75 ORGANIC SOFTWARE •Textwriterlll $111/25 * Datebook $269/25 'Milestone $269/30 PEACHTREE SOFTWARE General Ledger $399/40 Accounts Receivable $399/40 Accounts Payable $399/40 Payroll $399/40 Inventory 399/40 Mailing Address $399/40 for P5 Version add $1 1 9 Series 6-Peachtree CPA $799/40 Property Mgt $799/40 Passive Payroll $449/40 Series 7-Peachtree Sales Tracker $3049/55 AR-Sales Analysis $1299/50 Inventory $799/40 Order Entry $699/40 REDDING GROUP *Lynx $199/20 SOHO GROUP Matchmaker $ 97/20 Worksheet $177/20 SORCOM *Pascal/M Z80 $349/40 Pascal/M 86/88 $449/40 * Act 65 $149/20 "Act 68 *Act 69 •Act 86/88 $149/25 •Trans 86 $119/25 •Supercafc $269 SOUTHERN COMPUTERS •Raid $224/35 •RaidFP $349/35 •FFP $224/15 •Recover $ 75 •RADAR . . . $449/25 ISIS $224/20 STRUCTURED SYSTEMS GROUP General Ledger $849/40 Accounts Receivable $849/40 Accounts Payable $849/40 Payroll $849/40 Inventory $849/40 Order Entry $849/40 Analyst $224/25 Letteright $159/20 NAD $ 89/20 Qsort . $ 89/20 SUPERSOFT •Diagnostic II . . .$ 84/20 •Forth $149/30 *SSS Fortran $219/30 * Fortran w/RATFOR $289/35 *C Compiler $175/20 •Disk Doctor . .$ 84/20 •Term I $129/25 Term II $169/25 Z8000Xassembler. $449/35 Others less 10% WHITESMITHS C Compiler $600/30 Pascal (incl C) $850/45 Call for catalog and other listings * Available for Apple with Softcard 502 April 1982 © BYTE Publications Inc Circle 185 on inquiry card. Circle 165 on inquiry card. FLOPPY DISK DRIVES SPECIAL!!!!!!!! QUME DATATRAK 8 Virtually the industry standard. High quality/ reliability. Full featured, double sided, double density. Tanrion TM 848 $545 $525 quantity 1, $499 quantity 2 up. TANDON DOUBLE SIDED, DOUBLE DENSITY MINIS TM100-2 48TPI (500 KBYTES) Compatible with Northstar, Cromemco, TRS-80 TM100-4 96TPI (1000 KBYTES) Compatible with Zenith, Heath, etc. TANDON 5Y 4 " HARD DISKS TM 602 (5MB) TM 603 (10MB) $325 $425 $1195 .$1295 CONTROLLERS Tarbell single density kit ... . Tarbell single density A & T . , Tarbell double density A & T . CCS 2422 w/CPM 2.2 Godbout Disk 1 . $195 $310 $425 $350 $450 i MDA MXV-21 LSI-11 controller (RX-01, RX-02 compatible) , . $1050 MISCELLANEOUS 2 Disk drive enclosure ..... $ 95 {fits Siemens, Shugart, Qume) CP-206 power supply $110 (powers two floppies) Mini-Enclosure with power supply 1 drive $ 85 2 drives $120 Cable Kits 2 drives $ 35 3 drives $ 40 4 drives $ 45 Diskettes ss $39/10 - ds $59/10 CPU CCS 2810 $ 275 Godbout Z-80A $ 275 Godbout 8085A $ 295 MEMORY CCS 2065 64K dynamic $ 595 CCS 21 16 32K static $ 625 Godbout RAM 1 7 64K $ 675 I/O CCS 2710 4 SIO $ 325 Godbout Interfacer 1 $ 225 Godbout Interfacer 2 $ 225 Electrolabs POB 1608, Palo Alto, CA 94302 (415) 965-7040 NEW !!!! Qume Sprint 9 DAISY WHEEL PRINTER .. $2395 45 CPS, RO. Available in KSR version. Call for further particulars. Ribbons: $125/case Bidirectional tractor feed $225 NEW !!!! ABM 85 Video Terminal . . $ 895 — Detachable keyboard — Televideo 920, ADM 3A compatible — High resolution green phosphor (23 MHZ) — Extra multi-bus or S-100 slot for stand-atone capability Terms of sale: cash or checks, MC/ VISA. Min. order $25. CA residents add 6% tax. Prices subject to change without notice. All goods subject to prior sale. SUNNY LOW LOW COST POWER SUPPLIES FOR S-100, FLOPPY DISKS. KIT 1, 2 & 3 For S-100 R3 For Three 8" or 5 1 /4 M Disk Drives S-100 POWER SUPPLY KITS (open frame with base plate, 3 hrs. assy, time) ITFM USED FOR @ + 8 Vdc @ - 9 Vdc @ + 16 Vdc @ - 16 Vdc @ + 28 Vdc SIZE W x D x S3 2 in 1 Unit for S-100 and two 8" or 5 V Disk Drives. It fits most Disk System Mainframes. PRICE KIT 1 15 CARDS SOURCE 15A KIT 2 SYSTEM SOURCE 25A KIT 3 DISK SYSTEM 15A 1A 2.5A 3A 2A 2.5A 3A 2A 4A 12" 12" 14" AW AW AW 54.95 61.95 69.95 DISK DRIVE POWER SUPPLY "R3" regulated, open frame, assy. & tested 69.95 SPECS + 5V @ 5A OVP, -5V @ 1A + 24V@ 5A. SHORTS PROTECT 2 SIZES AVAIL , 1)9" (W) x 6V (D) x AW (H). 2) 9" (W) x AW (D) x 5V 4 " (H) OPTION 1 ) REPLACE + 24V BY + 12V. 2 ) FOR SIZE 1 ONLY, ADD ± 12V @ 1A, AT AN ADDITIONAL $12.00 IDEAL FOR THREE 8" or 5'/« FLOPPY DISK DRIVES. SUCH AS SHUGART 801/851. SIEMANS FDD 100-8/200-8 OR 100 -5 ETC DISK SYSTEM PWR SUPPLY "S3" open frame, assy. & tested, compact size: iq rro Court Son Luis Obispo, California 93401 (605) 541-4160 Circle 77 on inquiry card. Circle 120 on inquiry card. Circle 133 on inquiry card- \ferbatinr Floppy Discs SAVE 40% <£$£2r 51 i § § Specify soft, Price/10 /4 10 or 16 sector MD525 1 side/db! dens $27.30 MD550 2 sides/dbl dens 44.20 MD577 1 side/77 track 32.50 MD557 2 sides/77 track 44.20 8 9 t Critically Certified Soft sector FD34-9000 1 side/sgl dens 33.80 FD34-8000 1 side/dbl dens 39.00 FD34-4001 2 side/dbl dens 46.20 CHECKS - VISA - MC - C.O.D. (3 13) 777-7 780 ADD $2 SHIPPING LYBEN COMPUTER SYSTEMS 27204 Harper Ave. St. Clair Shores, Ml 48081 EPSON DOT MATRIX PRINTERS SUPER DISCOUNTS ON MX-80F/T l a NOW MX-80 L0 ^ R! IN MX-100 JgSm STOCK We also stock direct connect cables for TRS-80, Apple, Atari, Pet or RS 232 (209) 667-2888 © GRAPHICS ROM'S AVAILABLE /VL4CRC3TRONICS inc. H2S N Golden Sto»e Bva turtocn Colitorrna Q5380 EPROM -32 The only EPROM programmer you need! • IEEE-696 (S-100) EPROM programmer for single-supply (+5V) EPROMs. • Programs current 1K through 8K (byte) EPROMs plus future 16K and 32K EPROMs. • Personality Modules adapt board to different EPROM types- PM-1-2508, 2758 PM-4-2564 2516,2716 PM-5-2764 PM-2-2532 PM-6- 68764 PM-3-2732 PM-7-2528(TI-16K) • Zero-insertion-force socket accommodates both 24-pin and 28-pin EPROM packages. • DIP switch selection of programming ports and EPROM address for verification and/or use. • On-board DC-to-DC converter with adjustable regulator for programming voltage. • Programming voltage switched by software. • Double-sided PC board with solder masks, silkscreen and gold-plated contact fingers. • Documentation includes source listing of 8080/Z80 soft- ware for programming and verification. T $269.95 MIcroDynamtcs (assembled & tested) Price includes EPROM-32. documentation and two personality modules (specify). Ad- Momnhic tm Qoi 1 7 &hona\ modules - £795. Programming/ ."IvLcnM verification software on 8 inch single density CP/M-compatible diskette - $9.95. Corporation P.O. Box 17577 (90D-755-0619 MASTERCARD & VISA-TN residents add 6% sales tax Circle 242 oh inquiry card. Circle 245 on inquiry card, Circle 271 on inquiry card. FULL LINE ALL PARTS & COMPUTER PRODUCTS VC/C P.O. Box 4430X Santa Clara, CA 95054 "Will calls: 2322 Walsh Ave. (408) 988-1640 Same day shipment. First line parts only. Factory tested. Guaranteed money back. Quality IC's and other components at factory prices. INTEGRATED CIRCUITS Phone orders only (800) 538-8196 fELECTRONICS 7M8TTL 740ON 7W2N 7404N 7409N 7410N 7414N 7420N 7430N 74«N 7445N 7447N 7448N 7474N 7475N 7485N 7489N 7490N 7495N 741 DON 741 07N 74123N 74125N 74145N 741 SON 74151N 74154N 741 57N 74161N 741 62N 741 63N 74174N 74175N 741 SON 74192M 74193N 74221N 74298N 7436SN 74366N 74367N 74LSQON 74LS02N 74LS04N 74LS05N 74LS08N 74LS10H 74LS13N 74LS14N 74LS20N 74LS22N 74LS28N 74LS30N 74LS33N 74LS38N 74LS74N 74LS7SN 74LS90N 74LS93H 74LS95N 74LS107N 74LS112N 74LS113N 74LS132N 74LS136N 74LS151N 75 74LS155N 79 74LS157N .75 74LS152N 95 74LS163N 95 74LS174N .95 74LS190N 100 74LS221N 1 19 74LS2S8N 69 74LS367N 69 LINEAR CA3045 90 CA3046 1.10 CA3081 180 CA3082 190 CA3089 3,40 LM301AN.AH 34 LM305H 87 LM307N ,35 LM308N 98 LM309K 1.25 LM311H'N .64 LM317T 1 65 LM317K 3 75 LM318 1.49 LM320K-5 135 LM320K-12 1 35 LM320K-15 1 35 LM320T-5 85 LM320T-8 85 LM320T-12 85 LM320T-15 85 LM323K-5 4.95 LM324N 59 LM339N 99 LM340K-5 1 35 LM340K-8 135 LM340K-12 1 35 I LM340K-15 1 35 i LM340K-24 135 LM340T-5 75 IM340T-8 75 LM340T-12 .75 LM340T-15 75 L.M340T-18 .75 LM340T-24 .75 LM350 5.50 LM377 2 29 LM380N 100 LM381 160 LM382 160 LM709H 59 LM723H/N 49 LM733N 85 LM741CH .35 LM741N 35 LM747H/N 75 LM748N 50 LM1303N 175 LM1304 110 LM1305 1 27 LM1307 1 10 LM1310 2 75 LM1458 .55 LM1812 B25 LM1889 249 LM2111 175 LM2902 2 25 LM3900N 59 LM3905 125 LM3909N 95 MCI 458V 55 NE550N 1 30 NE555V 39 NE556A 65 NE565A 100 NE566V 1 50 NE667V 1 00 NE570B 4 75 78L0S 60 78L08 .60 7BM05 85 75108 1 49 75491 CN 50 75492CN 55 75494CN 89 A lo D CONVERTER 8038B 4 50 8700CJ 13.95 6701CN 22.00 8750CJ • 9.95 9400CJV/F 7 40 1CL7103 9 50 ICL7107 14 25 CO40O0 CD4001 CO4002 CO4006 CD4007 CD4008 CD4009 C04010 CD4011 CD4012 CD4013 CD4014 CD4015 CD4016 CD4017 1 CD4018 CD4019 CD4020 CD4021 CD4022 1 CD4023 CD4024 CO402S CD4026 1 C04027 CD4028 CD4029 CD4030 CD4035 CD4040 CD4042 CD4043 CD4044 CD4046 CD4049 CD4050 CD4051 CD4060 1 CD4066 CD4068 C04069 C04070 CD4071 CD4072 CD4073 CD4075 CO4076 CD4078 CD4081 CD4082 C04116 CD4490 ! CD4507 CD4508 ' CO4510 C04511 C04515 ; C04516 CD4518 004520 • CD4527 C04528 C04553 : CD4566 : C04583 ! CD4585 CD4019Z : 74COO 74C04 74C10 74C14 74C20 74C30 74C48 74C74 74C76 74C90 74C93 74C154 ; 74C160 74C175 74C192 74C221 74C905 I 74C906 74C914 74C922 ! 74C923 ! 74C925 I 74C926 I 74C927 I INTERFACE 8T13 8T20 8T23 8T26 t 69 8T28 1 95 8T97 .99 BT98 99 MOS MEMORY RAM 2101-1 195 2102-1 85 2102AL-4 1 25 2102AN-2L 1 65 2104A-4 4 95 2107B-4 375 2111-1 2.99 2112-2 2.99 2114 2.24 2! HL 300ns 2.50 2114L 450ns 2.37 4116 200ns 2 50 84116 200ns 15 40 MM5280 3 00 MM5321 9 95 MM6330 5 94 P5101L 8 95 420QA 1 1 50 UARTAFO AY5-1013 AY5-1014 3341 1702A 2532 2708 2716T1 2716 5 Volt 8 2716 5 Volt 39. 2732 DE9S 1 95 DA15P 2 10 OA15S 3 10 Complete Set 9 50 Stopwatch Kit 26.95 Auto Clock Kit 17. 95 Digital Clock Kit 19 75 RESISTORS tt wilt 5% ' 10 per type 05 100 per type 015 ""10 pe' type 39.95 39 95 34 95 49 95 " 5.75 HM6116 16 50 CLOCKS MM5311 4 95 MM5312 MMMM MM5369 MM5841 MM lit,: CT7010 ass CT7015 8.95 MM5375AMI 3 90 MM5375AG/N 4,90 7205 16.50 7207 2758 8741A 8748 8748-8 B755A N82S23 NB2S129 N82S131 4.95 NB2S136 875 NB2S137 8.75 DMAS '7 2.90 8223 3.50 CONMECTORS 30 pin edge 2.50 44 pjn edge 2 75 86 pm edge 4.00 100 pin edge 3.95 100 pin edge ww 4.95 f 50 5000 per type 0085 CLOSEOUT 14.45 v, watt 5% per type 05 IHP SWITCHES 4-position 85 5-pOSition ___ .90 6-posrtion :9Q 7- position .95 8 position 95 KEYBOARDS 56 key ASCII keyboard kit $74.95 Futty assembled 84 50 Enclosure Plastic 19.95 Melal Enclosure 69 95 UM HedT018 .15 Green. Yellow T01 8 20 Jumbo Red 25 Green, Orange. Yellow Jumbo 25 Cliplite LED Mounting Clips 4. 80 (spec red. amber, green, yellow clear) CONTINENTAL SPECIALTIES in Slock Complete line of breadboard test equip 7.50 15 95 7208 7209 MICROPROCESSOR 6502 6 95 6502A 950 6504 6 95 6522 8 75 6530 9.50 , 6532 14.95 ' 20 29 40 .49 WIRE WRAP LEVEL 3 8080A 3 95 8085A B.SO Z80A 6 00 780B 18.95 ZBO P10 6.50 ZBOA P10 5.95 ZBO CTC 5.95 ZBOA CTC 8.65 Z80 DART 15 25 ZBOA DART 18 75 Z80DMA 17 50 ZBOA DMA 27.50 /so moo 23.95 Z80AS10/0 28.95 ZBO S1Q/1 15.00 Z80AS1Q.'1 23 90 ZBO S1 0,2 23.95 Z80AS10/2 28 95 Z80BCTC 17 95 Z80B P10 17 95 8212 SPECIAL PROOUCTS 2 5MHzFreq Counter Kit 37.50 30 MM; Freq Counter Kit 47 75 lt> S/ i!6 l.UU IB 67 40 1 59 AC TRANSFORMERS 2 level 14 pin w* 20 FRAME WALL PLUG 6V 500 ma $4 00 10V 2 amp 57 95 ravsHLS 6.3V CT 600 ma 4 60 12V 250 ma 2 95 1 mh7 4 SO 1 zv 250 ma 1 . 95 1 2V CT 250 ma 3 75 \ uml Ht W 6V CT 600 ma 4 95 (2V 500 ma 4 50 4 MH> 3 95 12 6V CT 2 am P s 5 95 W 1 am P 5 95 ,MH 395 12 6V CT 4 amp 8 60 12V 2 amp 7 95 ,2u„ ,,, 126VCTBamp 10806.9 12V0C HMH7 im 2