I JULY 1988 A McGRAW-HILL PUBLICATION REVIEWS OS/2 Alternatives: VM/386and Concurrent DOS 386 Five Fast ATs^p ColorvueSE x ProBas NewSpace Sun's 386i: Workstation per • 25-MHz speed • "Open Loo • Multitasking • DOS conppali • High-resolution jgraphics f IBM's OS/2 Extended Edition 6 Short Takes Write Your Own TSRs Europe's "Viper" Chip ISDN Circuit Cellar yHTTTT^VtSKHM Multitasking S3.50 U.S.A. /$4.50 IN CANADA 0360-5280 ' '\ BORLAND PRESENTS I ml5 ^DVIEL^ tlMS QL^ rflSlCSt andttiost approachable implementation of that language" —Darryl Rubin, Al Expert, on Turbo Probg "Most powerful version of Basic ever" —Ethan Winer, PC Magazine, on Turbo Bask And able to leap onto "new ground in the price/performance arena'^ — John H. Mayer, Computer Design, onTurboC •*s ? V/£ / y ^ See the technological excellence of Turbo C, Turbo Pascal and Turbo Basic! Meet Turbo Prolog 2.0: Artificial Intelligence like you've never seen it! ■ : 'A The Critics Agree: Borland's "Turbo C . . . will stun you with in-RAM compilations that operate at warp speed." Turbo C's® sleek compiler is so fast and powerful, we used it to write our equation solver, Eureka."* Even better, all that muscle is wrapped in a smooth, integrated environment with every- thing you need to make writing, editing and compiling your programs a snap: • Compiles 10,000 lines per minute* • Online, context-sensitive help • ANSI compatible • Six memory models— tiny to huge • 450 library functions • Utilities: Librarian, Make, GREP • Source code for MicroCalc spreadsheet • Command-line version of the compiler • Inline assembly that lets you mix C and assembler System Requirements For the IBM PS/2"" and the IBM® family of personal computers and all 100% compatibles. PC-DOS (MS-DOS) 2.0 or later. 384K RAM. —Richard Hale Shaw, PC Magazine • Professional-quality graphics library supporting VGA, CGA, EGA, Hercules, and IBM 8514 • Interfaces with Turbo Pascal 4.0 and Turbo Prolog Just $99.95 44 A lightning fast, fully featured C compiler suitable for almost every- thing . . . Borland's Turbo C compiler is flexible, fast and friendly. —Peter Feldman, PC Week )) Heap Sort Turbo C 1.5 Microsoft C 5.0 Compile time 4.7 sec. 16.3 sec. Compile & link time 7.4 sec. 19.5 sec. Execute time 10.5 sec. 15.5 sec. Object code size 1119 1313 ution size 6392 7891 Sort benchmark run on an 8 MHz IBM AT using Turbo C version 1.5 and ihe Turbo Linker version 1.1; Microsoft C version 5.0 and the MS overlay linker version 3.61. "Turbo Pascal 4.0 flies 4.0 is ballistic!" -Toms*™, Almost from its introduction, Turbo Pascal® has been the world- wide Pascal stan- dard. It's fast. It's flexible. It's affor- dable. And it gives you full control. Compile more than 27,000 lines of code per minute*. And work in a complete, integrated programming environment with pull-down menus and a full-featured editor. You don't have to swap code in and out to beat the 64 K barrier; it's designed for large programs. Break your code into convenient modules and work with them swiftly and separately. If there's an error in one, you can see it and fix it. System Requirements For ihelBM PS/2™andlhelBM®famiiyor personal computers and all 100% compatibles. PC-DOS(MS-DOS)2.0or later. 384K RAM. t Customer satisfaction is our main concern: if within 60 days of purchase this product does not perform in accordance with our claims, call our customer service department, and we will arrange a refund. All Borland products are trademarks or registered trademarks of Borland Inter- national. Inc. Otter brand and product names are trademarks of titeir respective holders. Copyright ©1988 Borland International. Inc. Bl 123IA Turbo Languages are Super ! like a rocket . . . 1987 Programmer's Journal Powerful features include: • Producing EXE files • Separate compilation • Built-in project management • Graph unit including support for IBM CGA, EGA, VGA, and 3270. Hercules and ATT 6300 • Online, context-sensitive help *Runonan8MHzIBM PC AT. Add expertise: The Turbo Pascal Toolboxes Start with Turbo Pascal Tutor for just $69.95 and add the others as your interests and expertise grow: • Database Toolbox • Editor Toolbox • Graphix Toolbox • Numerical Methods Toolbox • GameWorks Toolboxes require Turbo Pascal 4.0 Just $99.95 each 44 Each new Turbo Pascal 4.0 Tool- box is a virtual treasure of program- ming methods and tips. —Giovanni Perrone, PC Week JJ Circle 34 on Reader Service Card (DEALERS: 35) "Turbo Basic compiles faster than anything I have seen." -Manwner t pc Magazine Turbo Basic® is the lightning-fast Basic compiler with a total devel- opment environ- ment that puts you in full control. Even novices can write professional programs with Turbo Basic's full-screen windowed editor, pull-down menus, and trace debugging system. You also get a long list of innovative Borland features like binary disk files, true recursion, and increased compilation control. Plus the ability to create programs as large as your system's memory can hold— not just a cramped 64 K. The choice is basic: Turbo Basic! Just $99.95! 44 Turbo Basic, simply put, is an incredibly good product ... Not only is this the most advanced BASIC ever, but Borland has lived up to its Turbo tradition. — William Zachmann, Computerworld J J Add another Basic advantage: The Turbo Basic Toolboxes • The Database Toolbox • The Editor Toolbox Toolboxes require Turbo Basic 1.1 Just $99.95 each. System Requirements For Ihe IBM PS/2'" and the IBM® family of personal computers and all !00% compatibles. PC-DOS (MS-DOS) 2.0 or later. 384K RAM. 640K to compile toolboxes. Compare the BASIC differences | Turbo Basic 1. 1 QuickBASIC 4.0 Compiler QuickBASIC 4.0 Interpreter Compile & Link to | „ stand-alone EXE J sea 7 sec. Sizeof.EXE 28387 25980 Execution time w/80287 0.16 sec. 16.5 sec. 21.5 sec. Execution time w/o 80287 0.16 sec. 286.3 sec. 292.3 sec. The Elkins Optimization Benchmark program from March 1988 issue of Computer Language was used. The Program was run on an IBM PS/2 Model 60 with 80287. The benchmark tests compiler's ability to optimize loop-invariant code, unused code, expression and condi- tional evaluation. "-— - — *X y^A PERFECT TO& f MAPPING SVST£M »JTO I '^'^H fl/U> uto/lK a»£Rc stuck. /y - »£w; *S6^ ■/ 3 s y iW L^ P Turbo Prolog 2.0: Powerful Artificial Intelligence for your real- world applications! New Turbo Prolog® 2.0 lets you harness powerful AI techniques. And you don't have to be an expert programmer or artificial intelli- gence genius! You get an all-new Prolog compiler that's been optimized to produce smaller and more efficient programs than ever before. An improved full-screen, completely customizable editor with easy pull- down menus. All-new documenta- tion, including a tutorial rich with examples and instructions to take you all the way from basic program- ming to advanced techniques. Even online help! System Requirements For ihe IBM PS/2™ and the IBM® family of [wrsonal computers and all 100% compatibles. PC-DOS (MS-DOS) 2.0 or later. 384K RAM. More new features! An external database system for developing large databases. Supports B+ trees and EMS Source code for a fully-featured Prolog interpreter written entirely in Turbo Prolog. Plus step-by-step instructions to adapt it or include it as is in your own applications! Support for the Borland Graphics Interface, the same professional-quality graphics in Turbo Pascal, Turbo C, and Qiiattro Improved windowing Powerful exception handling and error trapping features Full compatibility with Turbo C so the two languages can call each other freely Supports multiple internal databases High-resolution video support Turbo Prolog Toolbox is 6 toolboxes in one! More than 80 tools and 8,000 lines of source code help you build your own Turbo Prolog applications. Includes toolboxes for menus, screen and report layouts, business graphics, communications, file- transfer capabilities, parser generators, and more! Toolbox requires Turbo Prolog 2.0 Just $99.95 (4 If I had to pick one single recommendation for people who want to try to keep up with the computer revolution. I'd say, 'Get and learn Turbo Prolog.' —Jerry Pournelle, Byte 1/88 An affordable, fast, and easy-to-use language. — Darry I Rubin, AI Expert JJ Just $149.95! 60-Day Money-back Guarantee t For the dealer nearest you Gall (800) 543-7543 Circle 36 on Reader Service Cant (DEALERS: 37) INTERNA T I N A L BYTE JULY 1988 VOLUME 13 NUMBER 7 PRODUCTS IN PERSPECTIVE 67 What's New 89 Short Takes Dell System 310, a fast 80386 machine UR/Forth 1.10, Forth under OS/2 SoftPC, emulates an IBM PC XT in software EasyTalk, souping up the Toshiba laptop Grand View, for planning and project managing Forget-Me-Not, a calendar /timer TSR program FIRST IMPRESSIONS 103 Sun's Newest Workstation: the Sun386i by Tom Thompson A microcomputer workstation that has Unix multitasking with a window-based interface, and can run several virtual MS-DOS PCs. Ill IBM's OS/2 Extended Edition by Rich Malloy All the features of the Standard Edition, plus its own database manager and an array of communications interfaces. REVIEWS 118 Product Focus: Fast Drives for Modern Times by Stan Miastkowski 40-megabyte hard disks are becoming standard equipment. 134 Outclassing the AT by John Unger and Stan Miastkowski A look at the strengths and weaknesses of systems from Amdek, Arc he Technologies, Epson, Leading Edge, and PC's Limited. 147 Seeing Colors on the Mac SE by Don Crabb With the ColorVue SE, the Mac SE shows its true colors. 155 VM/386: A Virtual Solution by Namir Clement Shammas A multitasking program manager for 80386-based machines. 163 Concurrent DOS 386 by Alex Lane This multitasking operating system also supports additional terminals. 173 A Supercharger for BASIC Compilers by Namir Clement Shammas Cover Story: ProBas subroutines add speed Sun 386i/103 and power to Microsoft BASIC. 181 Graphic Design for the PC AT byLamont Wood Designer bridges the worlds of drawing and bit-mapped images. 189 Need Some Space? by Diana Gabaldon Increase the capacity of your hard disk with NewSpace. COLUMNS 197 Computing at Chaos Manor: Dr. Pournelle vs. the Virus by Jerry Pournelle Jerry observes the West Coast Computer Faire and gives a prescription. 211 Applications Only: From Shareware to Hyperware by Ezra Shapiro Ezra looks at MindReader, PC-Write, the Pointing Device Adapter, XHELP, and HyperDA. 217 Some Assembly Required: The Pitfalls of Pbrting, Part 1 byRickGrehan Our newest column illustrates the programming techniques that underlie today's and tomorrow's software, and gives you lots of useful, hands-on code besides. Product Focus/118 Graphic Design for the PC AT/181 2 BYTE- JULY 1988 COVER PHOTOGRAPHY: PAUL AVIS © 1988 IN DEPTH 226 Introduction: Multitasking 229 Fair Share by Jonathan Robie However you choose to implement it, resource sharing provides more efficient use of your system. 239 It's a Natural by Bud E. Smith From virtual memory to virtual machines, the 80386 is designed for the multitasking world. 251 Weighing the Options by Brett Glass A look at the inner workings of multitasking systems, and a comparison of products currently available. 259 First Come, First Served by Michael Benjamin Parker With Mailbox, you can write multitasking programs that you can port to many different machines and operating systems. 274 Resource Guide EasyTalk/92 DEPARTMENTS 6 Editorial: Dribble ware 11 Microbytes 22 Letters 35 Chaos Manor Mail 38 Ask BYTE 51 Book Reviews 151 Coming Up in BYTE READER SERVICE 350 Editorial Index by Company 352 Alphabetical Index to Advertisers 354 Index to Advertisers by Product Category Inquiry Reply Cards: after 356 PROGRAM LISTINGS From BIX: see 298 From BYTEnet: call (617) 861-9764 On disk or in print: see card after 324 Multitasking/226 FEATURES 278 The Ultimate Link? by Jay Duncanson and Joe Chew ISDN— a new technology that could change the way we use computers and telephones. 289 Ciarcia's Circuit Cellar: Computers on the Brain, Part 2 by Steve Ciarcia A look at the system software and some directions for HAL's use. 301 ATurboTSR by Scott Robert Ladd Turbo Pascal has everything you need to craft your own TSRs. 305 Fast Track vs. Failsafe by Dick Fountain It may not be as fast as other RISC chips, but VIPER's error-free design could be a life-and-death matter at Mach 3 . The Ultimate Link/278 BYTE (ISSN 0360-5280) is published monthly with an additional issue in October by McGraw-Hill Inc. Founder: James H. McGraw (1860-1948). Executive, editorial, circulation, and advertising offices: One Phoenix Mill Lane, Peterborough, NH 03458, phone (603) 924-9281. Office hours: Monday through Thursday 8:30 AM-4:30 PM, Friday 8:30 AM-1:00 PM, Eastern Time. Addiess subscriptions to BYTE Subscriptions, P.O. Box 7643, Tcaneck, NJ 07666-9866. Postmaster: Send addiess changes, USPS Form 3579, undeliverable copies, and fulfillment questions to BYTE Subscriptions, P.O. Box 7643, Teaneck, NJ 07666-9866. Second-class postage paid at Peterborough, NH 03458 and additional mailing offices. Postage paid at Winnipeg, Manitoba. Registration number 9321. Subscriptions are $22 for one year, $40 for two yeais, and $58 for three years in the U.S. and its possessions. 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Box 7643, Teaneck, NJ 07666-9866. © JULY 1988 -BYTE 3 BVTE EDITOR IN CHIEF Frederic S. Langa PUBLISHER/GROUP VICE PRESIDENT J. BurtTotaro OPERATIONS Glenn Hartwig Associate Managing Editor REVIEWS (Hardware, Software, Product Focus) Cathryn Baskin Associate Managing Editor, Dennis Allen Senior Technical Editor, Software, Curtis Franklin Jr. Senior Testing Editor, BYTE Lab, Stephen Apiki Testing Editor, BYTE Lab, Stanford Diehl Testing Editor, BYTE Lab NEWS AND TECHNOLOGY (Mlcrobytea, What's New, Short Takes) Rich Malloy Associate Managing Editor, D. 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Fax: (603) 924-7507. Telex: (603) 924-7861 . SUBSCRIPTION CUSTOMER SERVICE: Non-U.S. (201) 837-1315; inside U.S. (outside NJ) 1-800-423-8272; (inside NJ) 1-800-367-0218. Si* Officers of McGraw-Hill Information Systems Company: President: Richard B. Miller. Executive Vice Presidents: Frederick P. Jannott. Construction Information Group; Russell C. White, Computers and Communications Information Group; J. Thomas Ryan, Marketing and International. Senior Vice Presidents-Publishers: Laurence Altman, Data Communications; David J. McGrath, Engineering News-Record. Group Vice Presidents: J. Burt Totaro, BVTE; Frank A. Shinal, Dodge; Vice Presidents: Robert D. Daleo, Controller; Fred O. Jensen, Planning and Development; Michael J. Koeller, Human Resources; Julia Lenard, Systems Planning and Technology. Officers of McGraw-Hill Inc.: Joseph L. Dionne, Chairman and Chief Executive Officer; Robert N. Landes, Executive Vice President, General Counsel, and Secretary; Walter D. Serwatka, Executive Vice President and Chief Financial Officer; Shel F. Asen, Senior Vice President, Manufacturing; Robert J. Bahash, Senior Vice President, Finance and Manufacturing; Frank D. Penglase, Senior Vice President, Treasury Operations; Ralph R. Schulz, Senior Vice President, Editorial. BYTE and BYTE are registered trademarks of McGraw-Hill Inc. 4 B YTE • JULY 1988 Circle 278 on Reader Service Card — * HiWIRE Starts the Job that sm/IRTWORK" Finishes Introducing HiWIRE Wintek'ssmARTWORK^is used by thousands of engi- neers to design printed-circuit boards. Now Wintek intro- duces HiWIRE, an electronic- schematic program that is ecu / to learn and use. M\ ith a click of the mouse button, you can extract sym- bols from our library of over 700 common components and connect them with wires and buses. You can also easily modify the library's symbols or create your own by combining labels, lines, and arcs. HiWIRE Advantages □ Easy-to-learn mouse/menu- driven operation □ Complete documentation and tutorial D Extensive TTL, CMOS, micro- processor, and discrete- component libraries □ Rubberbanding □ Moving, copying, mirroring, and rotating of symbols □ Text-string searching □ Multiple display windows D High-quality schematics from printers and plotters □ Hierarchical-design sup- port; netlist and bill-of- materials utilities □ Schematic/ layout cross checking D 800 number for free tech- nical support System Requirements D IBM Personal Computer, PC XT, or PC AT with 320K RAM, parallel printer port, 2 disk drives, and DOS V2.0 or later □ IBM Color/Graphics Adapter or EGA with RGB color monitor □ Microsoft Mouse □ IBM Graphics Printer or Epson FX/MX/RX-series dot-matrix printer, and/or: D Houston Instrument DMP-40, 41, 42, 51, 52 or Hewlett- Packard 7470, 7475, 7550, 7580, 7585, 7586 plotter High Performance at Low Cost At $895, HiWIRE delivers quality schematics quickly and easily. You don't need to guess whether or not HiWIRE is right for you. Our money- back guarantee lets you try it for 30 days at absolutely no risk. Call (800) 742-6809 toll free today and put HiWIRE to work tomorrow. Wintek Corporation 1801 South Street Lafayette, IN 47904-2993 Telephone: (800) 742-6809 or in Indiana (317) 742-8428 Telex: 70-9079 WINTEK CORP UD "HiWIRE" Is a trademark, and "smARTWORK", "Wintek", and the Wintek logo are registered trademarks of Wintek Corporation. Europe: RIVA Terminals Ltd.. England, Phone: 04862-71001, Telex: 859502/ Australia Entertainment Audio Pty. Ltd., Phone: (08) 363-0484/Brazll: Comicro Intormatlca E Tecnologia Ltda., Phone: (041)224-8618 EDITORIAL Fred Langa DRIBBLEWARE BYTE polls COMDEX attendees on which operating systems will become dominant While we were at the Spring COMDEX in Atlanta, we asked attendees, "Which operating system will be dominant 5 years from now?" The answer we received was surprising— so surprising, in fact, that newspapers all over the country picked up the story. (You may have seen a brief summary in your local newspaper.) Here's the full story. The poll was carefully worded to avoid stacking the deck one way or the other. For example, the ballot specifically named several prominent operating sys- tems: the Macintosh's, DOS, OS/2, and two different flavors of Unix (traditional command-line Unixes and the new graphical-interface Unixes like "Open Look"). We also included an "other" category, so that respondents could name a less popular operating system. We collected over 5000 ballots: OS/2 and DOS each garnered about 1600 votes, the Unixes captured roughly 1300, theMacgota little over 200, and "other" racked up some 500 votes. In plain terms, there was no winner. In a random poll such as this, variations of a few hundred votes are meaningless: It's fair to say that DOS, OS/2, and the Unixes finished in a dead heat. The Mac's poor showing is not signifi- cant. Apple didn't exhibit at COMDEX, so I take the Mac's low numbers in the poll to be more indicative of Apple's ab- sence rather than low confidence in the Mac as a viable machine. A poll at a MacWorld Expo would undoubtedly show MultiFinder and A/UX ranking among the contenders. No Aberration The poll results were borne out on the show floor, where there was no flood of OS/2 software (a COMDEX joke re- ferred to the few true OS/2 programs as "dribbleware"). All the major software companies are working on OS/2 prod- ucts, but much of the software being shown was very, very far from finished. The general feeling at COMDEX was that OS/2 is indeed coming, but that it is likely to be one of the dominant operat- ing systems rather than the dominant sys- tem. Why? One answer lies in the large number of generally satisfactory alternatives to OS/2. For example, when I asked soft- ware developers what they were looking for in OS/2, the almost unanimous answer was "access to big memory," with multitasking a distant second, and Presentation Manager's graphical prow- ess an even more distant third. Of course, Unix already offers multi- tasking and access to major-league mem- ory. Such programs as Phar Lap's 386/ DOS-Extender— and even the somewhat clunky Lotus/Intel/Microsoft 4.0 stan- dard—also give you access to large mem- ory; other alternatives like PC-MOS/ 386, VM/386, and Concurrent DOS 386 (the latter two are reviewed in this issue) let you multitask your current DOS pro- grams. Also, programs like Windows give you a serviceable graphical interface without having to wait for Presentation Manager. In some cases, you don't even need a DOS alternative, shell, or extender for extraordinary flexibility. As I write this, I'm also simultaneously downloading my morning BIX mail and messages while printing out my daily schedule. Simple multitasking like this is no big deal. All it takes is my word processor, a back- ground telecommunications program, a print spooler, and plain old DOS 3.1. Even at this point, you probably al- ready can see why there's no clear win- ner in the operating-system wars. But it gets even more muddled. For example, there's the next upgrade of DOS waiting in the wings. It probably will overcome some of the fundamental limitations of the current DOS (like the 32-megabyte cap on hard disk size)— but the new DOS's file structure probably will be incompatible not only with cur- rent DOS, but with OS/2 as well. It's a safe bet that Microsoft will also offer an 80386-specific version of OS/2— one not hampered by the 80286's internal limitations (like the inelegant and time-consuming "soft reboot" it uses to switch from protected to real mode). Who's on First? All this is confusing for end users and a nightmare for software developers. In- stead of one or two or even three major standards, we're facing a future with up to a dozen viable ways to boot and run an Intel-family machine, plus at least three different ways to boot and run a Mac. And that's not even looking at the many excellent smaller operating systems. That's why our poll shows no clear winners. For better or worse, you and I are going to have to cope with and sort out more choices, more options, and more incompatibilities than ever before. Of course, a multiplicity of standards increases the need for objective informa- tion on competing standards, and that's BYTE's specialty. You can count on our broad, non-machine-specific coverage to help you sort through this morass of choices and to help you match the right hardware and software to the job at hand, regardless of brand. For your copy of our COMDEX re- port, or for reports of PC Expo or the up- coming MacWorld, please send $3 to: Show Report, BYTE, One Phoenix Mill Lane, Peterborough, NH 03458. Be sure to specify which show report you want and to include a return address. —Fred Langa Editor in Chief (BIX name "f langa") 6 BYTE- JULY 1988 maxell MINhfLOPPY DISK And then. . . j Maxell created ! the RD Series. • W- ! Kteca maxell MINU-RDPPY DISK iSlW'SSJ maxell 'The ■ Evolution cfthe before has this level of Reliability and Durability been available in floppy disks. Introducing the new RD Series from Maxell. Twice the durability of the disks you're now using. Twice the resistance to dust and dirt. And the RD Series is ten times more reliable than conventional floppy disks. The Gold Standard has always meant maximum safety for your data. Now it means even more. maxell Can you cope with fame? "ALR products make headlines. Broad exposure from trade reviews and national advertising campaigns create public demand. This makes ALR dealers very popular." Alan Weinberger - President - The ASCII Group, a 180 member nationwide chain Can you say goodbye to your middleman? "ALR only sells through authorized dealers which means you dont get a knife stuck in your back. It also means direct support from the factory. Support from ALR's sales staff, cus- tomer service staff and technical sup- port staff. ALR also offers Dealer Incentive Programs such as Flooring, Co-Op Advertising, and some of the highest margins in the industry." Tom Diroff - President - Technology Partners, Ann Arbor, Ml Do you have what it takes to be an ALR dealer? Can you be a "Yes Man"? "We've had to learn to say yes, a lot. Yes to speed, power and affordability. Yes to Novell expandibility and a complete variety of networking solutions." Sam Woo - President - MicroAge Computer Store, Dallas, TX Can you handle success? If you think you can live with this kind of success, you may have what it takes to be an authorized Advanced Logic Research Reseller. If you know you can handle satisfying customers with the most advanced computing systems available, or your looking for an ALR dealer who already is, call ALR today at 1 -800-366-2574 and well send you dealer information and a product package. Maybe you do have what it takes. TSSs: Advanced Logic Research, Inc. 10 Chrysler, Irvine, CA 92718 714-581-6770 FAX: 71 4-581 -9240 Telex: 5106014525, Answer back Advanced Logic 8 BYTE- JULY 1988 FlexNode ■■■■■■I ! O Ad n nerd Lo$k Rrs*,uvh. Inc. I V: i'„ I, I iiiiii.iiyiiiiiiiiilMyy i ■ FlexNode The biggest word in 20MHz performance. The FlexNode from ALR is the ultimate 20MHz workstation. As a workstation or stand alone PC, the FlexNode delivers 20MHz, 286 or 386 performance, with up to O-wait-states and 50MB of hard disk storage in a very small package. FlexNode offers plugable CPU cards designed for high performance and ease of service. With the choice of 286 or 386 speed, FlexNode is available in three basic configurations with pricing begin- ning as low as $1990.00. Standard Features include; 20MHz 286 or 386 CPU with respective 80287 or 80387 support 3.5" PS /2-compatible, 1.44-MB floppy disk drive 4-slot backplane with serial port and floppy disk controller 101 key enhanced keyboard 4.5"W x 7"H x 15"D For more information, or to find the name of the nearest ALR Authorized Dealer, give us a call at; 1-800-444-4ALR Circle 7 on Reader Service Card (DEALERS: 8) Advanced Logic Research, Inc. 10 Chrysler, Irvine, California 92718 - (714) 581-6770 FAX; (714! 581-9240 • IT LFX: 5106014525. Answerback Advanced Logic Sharpen Your PC Skills While You Build a Great Software Collection— Two disks each month filled with lots of great software for your IBM PC M , Apple II™ or Commodore 64/128.™ ONLY $6.65! Reviewers Love Our Monthly Software! Softdisk rating:" ■■■■ (4-stars) inCider, Apr 1987 "...I highly recommend Loadstar. If you can afford only one disk service, make it Loadstar..." Steve Leven, Commodore Microcomputers ". . .Big Blue Disk offers games, educational programs, product reviews, programming utilities, and even commercial programs. We had more fun than an ant at a picnic, and we're going to subscribe!.. .RATING: ■■■■ Value for Money' (4- stars) Family Computing Learn From the Experts Draw on the vast experience of our editors to provide you with carefully selected software you can use each month, from spreadsheets to role- playing games, from telecom- munications to accounting to recipe programs. With easy-to-use docu- mentation, you will master each new application with confidence and easeT Become Experienced Inexpensively Without investing a fortune, our monthly software will help you to see why your personal computer is the most versatile and powerful tool you own. You will know more about your computer , its capabilities, and software for it, than you would have thought possible. At $6.65 per issue, our monthly software is the best value in software today. Try our Monthly Software for Three Months Every month your postman will bring you the latest issue of our monthly software, contained on two unprotected 5W diskettes. Each issue is chock-full of our best software, including utilities, games, home and business applications, and educational programs. Order now and receive a special software gift absolutely free Apple II, C64/128, and IBM PC, and are trademarks of Apple Computer Inc., Commodore Business Machines Inc., and International Business Machines Inc., respectively. Available at Waldenbooks, B. Dalton Booksellers, and fine bookstores everywhere (cover price $9.95). BIG BLUE DISK (IBM PC version) Contents of Issue #20 • Crazy Eights Classic card game with a custom graphic card deck (how else can you get the Eleven of Spades?). • Print Utility Format documents to output on your printer. • Directory Label Printer Generate labels for disks listing filenames. • Fireworks Construction Kit Create your own simulated fireworks shows. • PC-Key-Draw Complete professional drawing program from OEDware." • The "DETAB" Command Converts tabs to multiple spaces when printing text files. (Available as a Back Issue) -%/ f Please rush my free gift and start my three month jLCSI subscription for only $19.95 postage paid. I understand that this is a trial subscription and that I am under no obligation to continue beyond three months. (Canada/Mexico $24.95, Overseas $27.95) Make checks payable in U.S. funds. □ BIG BLUE DISK'* for IBM PC and compatibles. (5'/i" disk) □ BIG BLUE DISK'* for IBM PC and compatibles. OVz" disk) □ SOFTDISK'" for Apple II family & compatibles. (5VT disk) □ LOADSTAR™ for Commodore 64 & 128 family. (5 l /4" disk) Name Address _ City. State ZIP+4 Telephone □ VISA/MC G AmEx Card# □ Payment Enclosed _ Exp. Date Call Toll Free 1-800-831-2694 (Louisiana Residents add 4% Sales Tax) BY078 SOFTDISK Inc • P. O. Box 30008 • Shreveport, LA 71130-0008 T}"0 T7T7 the bonus gift listed below which matches Ml 3\ £Zj d your computer when you order the next three issues of our monthly software for your IBM PC, Apple II or Commodore 64/128. FREE for IBM PC— "Best of BIG BLUE DISK" when you order BIG BLUE DISK. Nine of the best programs from recent issues. FREE for Apple II— "The Best of SOFTDISK" when you order SOFTDISK. Five of the best programs from recent issues. FREE for C-64/128— "The Best of LOADSTAR" when you order LOADSTAR. 14 of the best programs from recent issues. Your Satisfaction Guaranteed If you are not satisfied with your purchase for any reason, return your first issue for a full $19.95 refund. The free gift is yours to keep. You can't lose. 10 BYTE- JULY 1988 Circle 251 on Reader Service Card MlCROBYTES Staff-written highlights of developments in technology and the microcomputer industry Look Out, SQL: Here Come Object-Oriented Databases Although we've been told that the database in- terface of the future will be based on the Structured Query Language, some ex- perts predict that the rela- tional database model and SQL will be severely chal- lenged within the next 5 years by object-oriented data- bases. According to profes- sor L. A. Rowe of the Univer- sity of California at Berkeley, the relational data- base model is fine for tradi- tional business applications but inadequate for data- bases used for CAD, scientif- ic, and engineering applica- tions. Relational databases are suitable for applications requiring a small number of data types and a fairly sim- ple set of relations. But they are not well suited for data- bases involving new data types, such as graphics and other complex objects, and many relations with small numbers of rows, Rowe says. Rowe and a team of grad- uate students are working on a different type of database, which they call "Post- Flat-Panel VGA Displays Due Next Year in Portables By 1989 we'll be seeing portable computers sporting flat-panel VGA displays. One major manu- facturer of thin-film electroluminescent displays, Planar Systems (Beaverton, OR), now sells a 640- by 400-pixel electrolumines- cent screen and plans to in- troduce a 640- by 480-pixel by 16-gray-scale VGA display in 1989. Planar 's Rolland Von Stroh said the company is working with both domestic and Far East computer manu- facturers on a number of new projects involving flat- panel displays. Such screens are not limited to portable applications; some manufacturers plan to use 19- inch flat-panel displays in their engineering workstations. The next major develop- ment in the flat-panel field will be color displays, said Von Stroh. Planar will intro- duce full-color flat-panel displays in military applica- tions, such as airplane cockpits, in early 1990, and the first industrial applica- tions of full-color flat-panel displays will follow later that year, he said. Von Stroh predicted that flat-panel displays will even- tually capture a large share of the CRT market. By 1995 they could have 50 percent of the current CRT market, he said. Flat-panel displays have some advantages over CRTs. They are, of course, much more compact, have much less glare because of their flat surface, consume much less power (14 watts versus 50 to 100 watts), and are more reliable (accord- ing to Von Stroh, 45,000 hours mean time between failure versus 10,000 hours for CRTs). They cost 3 to 5 times as much to make as CRTs. However, Von Stroh claimed that thin-film electroluminescent displays are already displacing backlit LCDs and gas-plasma dis- plays because of things like better contrast and greater range of viewing angle. Ingres," that lets users add new data types and customize indexing methods depend- ing on the application. The database will also have for- ward- and backward-chaining rules for expert-system applications. Post-Ingres can store "objects," such as a graphics image or a forms specifica- tion, as a record in the data- base, based on an "object ID number. " Objects can be shared by multiple data- bases. The approach Rowe and his cohorts are develop- ing will make it possible to compile frequently used queries and also store them by ID number in the data- base. Thus, an application program could execute "query #47," which could be a compiled binary record in the database, for example. This would greatly improve performance of complex queries. Post-Ingres will also give users access to historical data stored on optical disks, re- searchers say. In fact, the system will support a three- level hierarchy of storage- hard disks, tapes, and opti- cal disks— allowing transpar- ent data access on all three types of media. This capabil- ity would be extremely use- ful for accessing historical data, such as archived med- ical or legal records. "Next-generation" data- base systems will appear within 3 to 5 years and will be developed using object- oriented programming and window interfaces on graph- ics workstations, Rowe pre- dicts. Alphanumeric termi- nals eventually will be replaced by graphics work- stations for most database applications, he added. continued Nanobytes • Despite being recog- nized as technologically impressive personal computers, Atari's ST and Commodore's Amiga haven't had the kind of market success enjoyed by machines from IBM et al. and Apple. So what's the problem? Part of the problem is that "computers are not powerful enough to be used at home for anything productive," says Neil Harris, director of product marketing at Atari. "I thinktheSTandthe Amiga are in the right direction, but we're still not there yet." Harris also blames the industry press for not covering the Atari machines enough. "The computer press is too busy analyz- ing its readership," he says. He also cites less malevolent forces, such as the RAM shortage. As for Atari's success in Europe, as opposed to the U.S.: "MS-DOS wasn't entrenched overseas, and there !s much less dispos- able income there, so when a lower-cost alter- native was introduced, it was embraced" by the Europeans. • Researchers at the Na- tional Bureau of Stan- dards (NBS) are work- ing on tools for measuring the performance and ef- ficiency of multiproces- sors. The tools differ from software measure- ment systems in that they don't affect the pro- gram that's being mea- sured. The researchers at the NBS Institute for continued JULY 1988 -BYTE 11 MICROBYTES NANOBYTES Computer Sciences and Technology hope to ex- amine such factors as in- formation flow and pro- cessing loads. • Marlboro Man goes optical: Optical data pro- cessing is making its way into the commercial world. Carnegie-Mellon University and Philip Morris Corp. have built a device for inspecting cigarette packs. The sys- tem uses pattern-recogni- tion techniques and is considerably faster than digital systems, a CMU spokesperson said. • "There is too much piracy of intellectual property, including computer software, "U.S. trade representative Clayton Yeutter told the International Computers and Communications Conference in Washing- ton, D.C., recently. There are standards for pat- ents, trademarks, and copyrights, but no en- forcement teeth to make these rules effective, Yeutter said. "levant some clarification and effec- tive delineation of funda- mental principles to pro- tect intellectual property rights," he said, and he threatened that the U.S. will take an aggressive approach with other gov- ernments in order to achieve enforceable agreements. • Are you budding? Have you written some software but can't find a publisher? A company called WCE Publishing (Surrey, BC, Canada) says it's looking for "budding software writ- ers with publishable software" that could sell for between $50 and $100. The company thinks "the days of the megabuck software prod- uct" are over. You can continued New Chip Could Mean Lower-Priced 80386 Machines I n an effort to minimize software compatibility problems across its line of processors, Intel (Santa Clara, CA) has developed a new version of its 80386. The new chip is aimed at "mid- range personal computers," which don't require the high performance offered by the current versions of the 80386 with the 32-bit data bus. The new 386SX runs at 16 MHz and uses a 16-bit data bus and 24-bit address bus, similar to the 80286. However, the 386SX is sup- posed to be able to run all 80386 software, although at lower performance levels than its full 32-bit brother. Intel rates the performance of the 80386 at 4 to 6 VAX million instructions per sec- ond (depending on if the clock speed is 16, 20, or 24 MHz) and the 386SX at 3 MIPS. Intel is planning to re- lease a similar version of the 80387 numeric copro- cessor; the 387SX is fully compatible with the 80387. The 386SX has the po- tential to make 80386 soft- ware accessible on more af- fordable machines. With the advent of powerful pro- grams such as Windows/386, which runs exclusively on the 80386, the chip has be- come attractive to a wide range of users. However, cur- rent 80386 machines are too expensive for many indi- viduals. The 386SX could be the ticket to 80386-based software for those users. With the introduction of the 386SX, Intel will discon- tinue production of the 16- MHz 80386. The chip maker will focus on high perfor- mance with the 80386 and on lower-cost computers with the 386SX, said product manager Bruce Schechter. The 80386 will continue to be aimed at high-end per- sonal computers, while the 386SX will become the main processor for midrange machines like today's AT class or PS/2 Models 50 and 60. Meanwhile, the "80286 will move downstream to the lower end of the market," said Schechter. Intel expects the 80286 to become the en- try-level processor in its product line; the 8088/8086 processors will gradually dis- appear, Schechter said. Intel emphasized that the 386SX is not pin-compatible with the 80286. In fact, the 386SX is considerably small- er than its predecessors. With the less complex cir- cuitry required in building a 16-bit bus, the 386SX could be ideal for portable com- puters and add -in boards. Several manufacturers al- ready have production units; although Intel won't name names, the most likely candi- date is IBM, which plans to introduce 80386-based ver- sions of the Model 50 and Model 60 next year. The chip will be shipped in volume in the fourth quarter. Initial- ly, the 386SX will cost $212 in quantities of 100 (the 80386 is $299). But Schechter said that price dif- ferential between the 80386 and the 386SX will increase with volume production. Will Neural Nets Put Patton in a Box? Depending on the results of the first part of a multiphase contract awarded by the U.S. Depart- ment of Defense (DoD), the next generation of battlefield commanders could have pearl-handled Tempest-rated cases around their silicon brains— sort of a cloned Pat- ton on casters. Computer experts don't agree on the po- tential of neural networks, but the DoD is investing heavily in the new technol- ogy and has just awarded a contract to Hecht-Neilsen Neurocomputers (San Diego, CA), one of the first com- panies to develop commercial neural network products. So far, nearly all the research funding for neural network projects is DoD-related. The Electronics Technol- ogy and Devices Laboratory of the U.S. Army Labora- tory Command awarded Hecht-Nielsen this contract to "identify Army battlefield problems and develop a de- sign for a battlefield neuro- computer to satisfy the pro- cessing requirement." Jacqueline Townsend, a spokesperson for Hecht-Niel- sen, said this first $50,000 phase is for "proof of con- cept. " Assuming that the concept is accepted by the Army, phase two might be- gin to define the actual sys- tem, which, she said, "we probably won't be able to talk about." Asked if a battlefield computer might consist of one of Hecht-Nielsen 's Anza neural network plug-in boards for an IBM PC AT in a Tempest box, Townsend replied that it is too early to say what, if any, future con- figurations might be. While the idea of a swag- gering robotic commander is a bit farfetched, the inher- ent capabilities of neural net- work s, such as learning, pattern recognition, and asso- ciative memory, would lend themselves to defense appli- cations. Performing danger- ous and repetitive tasks, radar, sonar, image pro- cessing, data manipulation, delivery of defense systems with "humanlike discrimina- tion" capabilities, "oppos- ing force modeling (war- gaming), and weapons aiming and steering" are some of the areas where neural networks might be used, according to Hecht- Nielsen. continued 12 BYTE- JULY 1988 If you can see the difference, you must be looking at the price. Hewlett-Packard Company 18110 S.E. 34th Street Camas, WA 98607 Dear Reader: This letter was printed on two of the finest printers available today. One half on a laser printe x , tne other on the new HP DeskJet Printer. But which one printed which half? Hard to tell, isn't it? J Small and quiet enough for your ow n desk, our HP DeskJet Printer gives you clean, crisp text and graphics. Just like a laser. You get perfect printing from A to Z. Look for yourself. -■ The New HP DeskJet Printer. Laser-Quality Output for Under WOO. m HEWLETT PACKARD ©Hewlett-Packard Co. 1987 Circle 116 on Reader Service Card JULY 1988 -BYTE 13 MICROBYTES NANOBYTES reach WCE Publishing at 65-13880 74th Ave., Surrey, BC, Canada V3T 2T8, (604)583-1600. • IBM hopes to push the "standardization" of its Micro Channel archi- tecture by licensing its patents to companies that want to build PS/2-like computers, says Gordon Campbell, chief executive of Chips & Technologies (San Jose, CA). "IBM said it will license the patent portfolio. That's very different from li- censing the technology. We in the industry have missed what IBM has been saying all along; we've heard only what we wanted to hear." Camp- bell said that by licensing the IBM patent portfo- lio, "a company is free to build Micro Channel products, but they have to do all the work. "IBM said that licensees will have to pay "a maximum of 1 percent of sales reve- nue" on a product that uses an IBM patent; the maximum is 5 percent, depending on the number of patents involved. • Some of the well-to-do are computing. Thirty- eight percent of "afflu- ent households" in the U.S. have personal com- puters, says a study by In- ternational Research As- sociates (Mamaroneck, NY). And what's the machine of choice among the upper crust? This study says 13 percent of the respondents have an IBM PC, 10 percent have Apples, and 7 percent have Commodores. • Versacad (Huntington Beach, CA) has come out with three HyperCard stacks for users of its VersaCAD/Macintosh Edition. The hyperware— Bill of Materials, Door & Window Scheduling, continued Compromise Brings Hope of High-Speed Modem Standard There's no standard yet— but it's coming. That's the word from two U.S. companies spearhead- ing the work for a standard modem system that will work faster than 9600 bits per second over regular dial-up phone lines. USRobotics (Skokie, IL) and Telebit (Mountain View, CA) have reached a compromise and asked CCITT, the Euro- pean standards agency, to give them more time to de- velop a complete standard. USRobotics (USR) is pro- posing a system with one high-speed channel, similar to current lower-speed modems. According to Dale Walsh, USR's vice president of engineering, the main channel would send data at a top speed of 14,400 bps, while a 450-bps back channel would perform error cor- rection and other protocol functions. USR' s proposal is supported by Rockwell, Racal-Vadic, and Paradyne. Telebit' s proposed sys- tem uses more than 500 chan- nels, each operating at rela- tively low speed. According to Ted Brown, manager of systems engineering at Tele- bit, the system normally sends data at up to 18,000 bps, though lab results show speeds of up to 28,000 bps. Under the compromise, the USR single-channel sys- tem would be mandatory, with Telebit 's multichannel system as an option, and a system for selecting between the two. Walsh said USR was pleased that work toward a standard would continue. "We've made significant progress, and this way we can work as a team to make more progress," he said. D wight Decker, Telebit 's di- rector of modem engineer- ing, agreed: "The critical thing is that the compro- mise means there really will be a standard." Decker said the compro- mise was supported by eight modem manufacturers and the national standards agen- cies of Germany, France, Spain, Sweden, and Switzer- land. Both he and Walsh Video Could Be the Key to Good Color Printers Forget that serial or par- allel port connection for your printer. To get the state of the art in color printer technology, you may soon be hooking up your computer's video output di- rectly to the printer. Sony has developed a thermal-transfer color printer that, while designed pri- marily for broadcasters who want still photos from videos, offers a tantalizing glimpse of where color printer technology is going. The UP-5000 does have an RS-232C port, but it's used for picture editing and control, not for carrying the actual print data. The printer accepts a wide variety of video inputs, including standard National Television System Committee (NTSC) video and analog RGB, and other standards like differ- ential R-Y, B-Y and S- video. The interface digitizes 8 bits of video and can print 256 variations of each of the three primary colors (ma- genta, yellow, and cyan). That amounts to something like 10 million possible colors per pixel. The printer captures images in an internal buffer and stores up to two frames. You can view the image on a color monitor and adjust the color and tones under com- puter control. A full-size print from the UP-5000 is 6 by 4!/2 inches, and the unit will also do overhead trans- said a draft standard should be ready for examination by the full study group early in the next CCITT plenary session, perhaps as soon as next February. USR favors a traditional approach, using a single main channel running at up to 14,400 bps. Telebit wants multiple channels running up to 28,000 bps. USR's Walsh said that a multichan- nel system can't really run that fast. "To achieve the high speeds claimed [by Telebit], they're operating beyond the available band- width on a voice line," he said. "As soon as they get in- terference on a real phone line, it falls back to slower speeds." Telebit' s Ted Brown countered that the slower speeds are still faster than a single-channel system— up to 18,000 bps. In addition, multichannel modems can drop back by as little as 100 bps at a time; traditional modems, on the other hand, must drop by 2400 bps at a time, he said. parencies. It takes 67 sec- onds for it to do its work on each print using special color thermal paper, and you can print multiple copies from the frame buffer. Print quality is stun- ning—virtually indistinguish- able from a commercial color print, not at all like the muted colors from most of today's color computer printers. As you might ex- pect, though, it's not cheap. The UP-5000, which will be shipped in July, has a re- tail price of $7000. But a Sony spokesperson said he expects the cost of the tech- nology will fall dramatically in the next couple of years, bringing this type of color printer within the price range of individuals and small companies. continued 14 BYTE- JULY 1988 Circle 124 on Reader Service Card — » Are You Floating on an Ocean of Data? You need Navigational Guidance. Discovers Relationships and Knowledge Hidden in Large Databases Navigate an Ocean of Data Everyday, all over the world, the number of databases and the amount of data in each database increases. The increasing size of a database makes it harder and harder to understand what the data means. Whether you are part of a government agency, bank, engineering firm, insurance company, hospital or any organi- zation which relies on computers, your database already contains vast amounts of hidden knowledge. You could, of course, get an overall view of some of the characteristics of vour data by using statistics. But The Machine Learning ystem™, picks up where statistical echniques leave off. It helps you uncover the knowledge within your database by combining symbolic data analysis, induction and deduction to discover inter- dependencies and relationships. Make Better Decisions If you already use your data for decision making, IXL (Induction on extremely Large databases) can help you make better decisions by providing knowledge which may surprise youi IXL is flexible and allows you to tailor your own ideas, which may involve inexact and compound concepts, by defining rules and frames. It expects inaccuracies and omissions in your data and allows you to define your own thresholds of error tolerance. Use a New Technology IXL relies on a novel and advanced machine learning algorithm specifically designed for dealing with large databases. It is not just another simple imple- mentation of the ID3 algorithm, but combines insight from a number of powerful induction methods such as AQ/INDUCE, RX/Radix, etc. The induction method can be based on user defined deductive rules, frames and inheritance methods; providing a uniform integration of induction and deduction. Experience a Higher Level of Versatility You don't have to be an expert in Al or statistics to use IXL. An intelligent user interface controls your top level interaction and allows you to define your own criteria for induction with a great deal of ease. Our products are known for their efficiency and ease of use. - You may run IXL by itself or use our Intelligence/Compiler™ expert system development environment to define your own forward, backward or inexact rules, calls to C functions, frames and inheritance structures to be used with IXL. IXL includes its own data manage- ment module and data transfer ability, and accepts data in a variety of formats including dBASE-lll™, Lotus 123™ and ASCII files. You Need IXL Now! If you have a database, you need IXL now. The hidden knowledge you are unaware of today could influence your decisions for Yes, I would like to discover the knowledge hidden in my database. D Send me IXL at $490 Q Send Intelligence/Compiler at $490 Address: . Telephone: . □ Visa □ Mastercard Number: Expiration Date: . D Check - Q Money Order is enclosed. Shipping and handling: US $9.00, Canada/Hawaii Air $15.00, Overseas Air $35.00. System Requirements: IBM PC/XT, PC/AT or PS/2; 512K memory. Send coupon to: Intelligence Ware, inc. Leading in Artificial Intelligence Applications™ 9800 S, Sepulveda Blvd., Suite 730 Los Angeles, CA 90045 (213) 417-88% MICROBYTES NANOBYTES and CAD Text Proces- sor— is packaged with ver- sion 1.1 of VersaCAD for the Mac. • It seemed an unlikely fit when Autodesk (Los Gatos, CA) bought into Ted Nelson's Xanadu. But the maker of Auto- CAD sees the possibility of using hypertext as a means of managing and sharing CAD drawings generated by AutoCAD. John Forbes, project manager for AutoCAD, said he envisions a dis- tributed drawing manage- ment system in which users can connect archi- tectural and engineering drawings to text com- ments. (For example, a user could point to a loca- tion on the drawing and continued No More Golden Vaporware: Xanadu Products Next Year, Nelson Says The first products based on the Xanadu hypertext concept will ship sometime next year, say Ted Nelson and his Xanadu team. Nel- son said the time has come to "get this mother out of the closet and onto peoples' desks and into their minds. We're a member of the Gold- en Vaporware Club, along with Alan Kay's Dynabook.' The Xanadu Hypertext System, said Nelson, would create "a new unification of applications. We're going to create a uniform data struc- ture that developers of all types of applications can use." A preliminary system will be delivered to devel- opers late this year, accord- ing to Xanadu' s Roger Gregory. "We're looking at Suns, Macintoshes, and IBM PCs as platforms," he said. "We have something that's real," Gregory said. "You can see that it's real because it crashes." Big Changes to the Chip Not Likely, Inventor Kilby Says Nearly 30 years after he invented the computer chip, Jack St. Clair Kilby says improvements in the memory, performance, and cost of his invention are get- ting harder to come by. "Nothing goes on forever," he told the new Austin, Texas, chapter of the Ameri- can Electronics Association recently. "There may not be another 5 orders of magni- tude of improvements to be made. Certainly not with the techniques we now use," he said. The industry needs to fo- cus on improving chip pack- aging, according to Kilby. Kilby said he's not pessi- mistic about the future of the IC, which he invented in 1958. He said he's simply mindful that "30 years is an incredibly long time in the history of electronics for the domination of a single device. " continued Receiving Report Transmitted Invoice Price, Qty f Part# Matched Invni"-> stamped :oded 1,00 K! I •C* t ■I (c) ion Checks Printed & Signed j. 1 1 T Check Register Open Accounts Payable ! (e) (e) T *---► A/P Distribution neral &&■ *s&* *?$** BYTE- JULY 1988 PATT0N&PATT0N 81 Great Oaks Blvd., San Jose, CA 95119 1-800-525-0082, Outside California 408-629-5376, California/International *plus shipping. In California add tax. Circle 199 on Reader Service Card FROM ZORTECH INC. The change to a pure language Now, C programmers can move over to C++ with Zortech C++ - the world's first 'true 9 C++ compiler for MS-DOS machines. Zortech C++ is a 'true 9 compiler and fully conforms to Bjarne Stroustrup's specification as outlined in his book 'The C++ Programming Language 9 . Previous implementations of C++ were actually 'translators 9 - only able to translate C++ source code into C. Of course, this was unacceptable due to the long trans- lating and compiling times. Now, C++ comes of age with the introduction of the world's first true C++ compiler- from Zortech! ■ Object Oriented Programming C+ + is to C what Modula 2 is to Pascal. C++ brings 'classes 9 to C, so you can create separate modules that contain their own data and data-related operations. These 'classes 9 then become new types that can in turn be used to create further modules - this allows you to practically create your own language. ■ ANSI C Superset You don't have to throw away your existing C programs - C++ is a superset of ANSI C. Now, you can take your Microsoft C or Turbo C compatible programs and easily migrate to C++ to take full advan- tage of the new C+ + features. • • • • • • < * • • • • • ZORTECH SrON LONDON HANKFU»T Circle 284 on Reader Service Card • Jf YES! T^ W Rush me ^^ C++ as shown ^^ f below: ^^ f D Zortech C++ D C++ Book \^ • W $99.95 $29.95 ^^ MSA/MC/COD/CHECK ACCEPTED ^ ^r Name f Address J Phone JfVlSA orMC Exp. Date ■ 'Codeview' Compatible Zortech C++ is compatible with 'Codeview' - Microsoft's industry standard source code debugger. ■ Improved Program Structure As stated in 'The C++ Programming Language', by using C++ "It would not be unreason- able for a single person to cope with 25,000 lines of code'.' ■ Other benefits Here's just a few: Operator overloading, overloading function names, default arguments to functions and better type checking. ESSENTIAL READING! This 325 page book The C++ Programming Language' by Bjarne Stroustrup contains the original definition of C++. All the examples shown in this book have been suc- cessfully compiled and executed with the Zortech C++ Compiler. To: ZORTECH INC. 361 Massachusetts Ave., Arlington, MA 02174. V Tel: 617-646-6703. Fax: 617-648-0603. • CALL THE ORDER HOTLINE 1-800-848-8408 <1 MICROBYTES NANOBYTES retrieve a related descrip- tion or report on the de- sign characteristics of that piece of the drawing.) "We see hypertext as a means to manage infor- mation in a more intelli- gent way," said Chris Record, Autodesk vice president of business de- velopment and now presi- dent of Xanadu. • The Association of Personal Computer Con- sultants has formed with the intent of "certifying true professionals" in the field. The group plans to issue credentials and a statement of ethics "to acceptable profession- als." If you think you might be acceptable, writetotheAPCCatP.O. Box 14430, Philadel- phia, PA 19115. Apple Wants Developers to Push Mac into 32-bit World Apple Computer (Cu- pertino, CA) and out- side developers are working to move the Macintosh into the world of 32-bit comput- ing. And since most current Mac programs operate pri- marily in the 16-bit realm, this direction is the one that has the most implicit fallout for developers. Some third parties have widened their programs for 24-bit-deep color monitors and cards, but those are the exceptions. Apple is encouraging de- velopers to think in 32-bit terms. For its part, the computer maker has sug- gested revising the system software to accompany the use of a 68030 processor in its machines (Apple officials have hinted at a Mac SE with an 030 in it). Some peo- ple at Apple's Spring De- velopers' Conference said Apple is considering a "fat TECHNOLOGY NEWS WANTED. The news staff at BYTE is always interested in hearing about new technological and scientific developments that might have an impact on microcom- puters and the people who use them. We also want to keep track of innovative uses of that technology. If you know of advances or projects relevant to microcomputing and want to share that in- formation, please contact the Microbytes staff at (603) 924- 9281, send mail on BIX to Microbytes, or write to us at One Phoenix Mill Lane, Peterborough, NH 03458. slot" (one that addresses more than 24 bits in the slot) and "fat pixels" (up to 32 bits deep). The move to 32 bits falls in neatly with the closer ties between Apple and DEC; if Apple software runs at the 32-bit level, DEC compati- bility is easier. It will mean a total rewrite of Apple printer drivers, for example, to achieve this. It's not clear what that would mean for a company that has existing special drivers to convert QuickDraw into direct printer output, but a complete rewrite of these kinds of drivers is implied by any change in QuickDraw. "Apple is asking a lot in moving to 32 bits. I think they realize they are going to need better error-catching tools if applications are going to get written in a decent time frame, " said one developer. TAKE A "LQQK" A T THIS DOUBLE HEADER! ^Introducing ROMX-2XL EPROM EMULATOR Introducing the NEW ROMX-2XL Megabit Eprom Emulator! When GTEK® created the ROMX-2 Eprom Emulator in 1987, a whole new world opened up for engi- neers. Now GTEK® has extended the capabilities of the ROMX-2 in the ROMX-2XL. In addition to 2716-27256 sizes, you now have 2532, 2532 A, 68764, 68766, 27512, 27010, 271001, 271024, and 27210! If you are not familiar with eprom emulators, they give you the capability of eliminating the remove eprom/program eprom/insert eprom, steps of program code development. There are 2 models of ROMX-2 available for your use. The ROM X- 2 Eprom Emulator gives you the normal 2716-27256. If 27256 isn't enough, then the ROMX-2XL is what you need! All the models come with communications software for PC/XT/ AT type computers, and supports 16 and 32 bit systems. —Control target system with built in hardware reset lines. — Auto-Emulation. All commands in conversational format. —-Non-Volatile battery ram up to 128Kx8 (Megabit) —Baud Rates to 19, 200. Free communications software included. —Access time 150NS. Faster optional. Compatibly yours, Dos PCSS-8X 8 PORT SERIAL BOARD COMMON PROBLEM Have you ever purchased a serial board only to dis- cover that you've spent your money on a product that wasn't compatible with your system, required device drivers and/or had limited capabilities? If this is the case, we have a SURPRISE FOR YOU! Finally, a UNIQUESOLUTIONtoyour problem hasbeendeveloped. GTEK®, Inc. has designed the PCSS-8X an 8 port serial board for your IBM, PC, XT, AT and compatibles that can virtually perform any task you desire. This increases you company's productivity. This unique board was truly made for YOU and your DOS compu- ter in that the PCSS-8X has more maximum number of DOS com- patible ports than any of the competing products. In fact, the PCSS- 8X surpasses its competitors in terms of input/output functionality, handshaking, maximum port development, price and user applica- tion. READ ON! — MUX/DEMUX —BULLETIN BOARDS —PRINTER SHARING —DATA CONTROL/AQUISITION — CAE/CAD/CAM —UNIX/XENIX Still asking "why the P€SS-£%?" Because if you want the BEST serial board on the market, GTEK® has it! So order the PCSS-8X Serial Board today. It's the mulfciport serial card that- has been signed, "CQMFATIBLil YOURS, DOS!" ORDER TOLL FREE 1-800-255-GTEK (4835) FAX: 1-601-4870935 TELEX 315814 (GTEK UD) MS & TECHNICAL SUPPORT 1-601-467-8048 tlTEK Registered Trademarks - PC/XT/AT= IBM; UNIX = AT&T; XENIX = p DEVELOPMENT HARDWARE & SOFTWARE * P. O. BOX 2310 ■ «♦*■ BAY ST. LOUIS, MS 39521-2310 U.S.A. = Microsoft; ROMX-2/XL, PCSS-8X = GTEK* Inc. 18 BYTE- JULY 1988 Circle 111 on Reader Service Card (DEALERS: 112) More Board for the Buck That's what the EGA game comes down to. 100% IBlVf EGA compatibility is essential. But today you need more. So what does the Everex Micro Enhancer deliver? How about extended EGA resolutions like 752 x 410 and 640 x 480, and 132 column text modes. Or the ability to use those resolutions while running Microsoft® Windows, Lotus 1-2-3,® Symphony,® AutoCAD,® GEM,® Ventura Publisher,™ PC Paint" and VersaCAD®. That's nice. But what if your Hercules® and CGA applications ran on an EGA monitor. And if an autoswitch feature automatically adjusted modes to the software running, so that you wouldn't have to hassle with switch settings. Or if there was an optional parallel port to save money and space. Wouldn't that be better? This all comes from a leading supplier of EGA cards and costs so little that you wouldn't believe it's made in the United States. That's more board for your buck. It's simple. More features for less money. Everex has the answer. EVER for Excellence is a registered trademark and EVEREX and Micro Enhancerarelradeniarks of Everex Systems. Inc. Hercules is a registered trademark of Hercules ComputerTechnologies. Inc. Lotus. 1-2-3 and Symphony are registered trademarks of Lotus Development Corporation. Microsoft is a registered trademark of Microsoft Corporation. AutoCAD is a registered trademark of AutoDcsk. GEM is a registered trademark of Digital Research. Inc. Ventura Publisher is a trademark of Ventura Software. VersaCAD is a registered trademark of VersaCAD Corporation. PC Paint is a trademark of MSC Technologies. Inc. IBM is a registered trademark, of International Business MachinesCorp. 91988 Everex Systems, Inc. All rightsreserved. For more information or the name of your nearest Everex dealer please call: in usa 1-800-821-0806 in caiif 1-800-821-0807 EVER for EXce/lence® 415-498-1111 48431 Milmont Drive, Fremont, CA 94538 Circle 292 on Reader Service Card (DEALERS: 293) The Dicoiiix 150 printer* Completes The silent partner --- : most any system. Quietly that fits In a briefcase. Circle 82 on Reader Service Card ft A Kodak Company 3100 Research Boulevard Dayton, Ohio 45420 1-800-D1CONIX Letters Memory Management I have a few comments concerning the "Overview of Memory Management" by Randall L. Hyde (April). The article was instructive, under- standable, and well written. I appreciate the effort taken to explain what many users and programmers find to be "black magic" about computers: operating sys- tems and memory management schemes. Thrashing is not caused by a poor choice of replacement algorithm. A poor replacement algorithm will precipitate thrashing on a loaded system; the fact that so many replacement algorithms are explored in the literature is a testimonial to the importance placed on the subject. Thrashing is caused by overloading a virtual memory system. A nonthrashing system running at peak load with a poor replacement algorithm will perform bet- ter with a good replacement algorithm. An overloaded system will thrash regard- less of the replacement algorithm used. The real problem, then, is not the re- placement algorithm, but load control. I think 5 years is too optimistic a time frame for seeing PCs with virtual mem- ory being generally used. Virtual mem- ory systems are useful in the multiuser, multitasking environment that is the cur- rent niche for mini and mainframe prod- ucts. The boundaries between micros, minis, and mainframes are dissolving with today's hardware advances, but be- fore we see "deskframes" throughout the office, several major advances must occur: • There must still be work on the micro- processor itself before it is capable of supporting the high I/O rates that are necessary to page efficiently. Where is the equivalent of the channel in the future microprocessor market? Traditional pre- emptive direct memory access won't cut it. • Memory costs must fall dramatically before the general user can afford a sys- tem large enough to need paging. In to- day's mainframe world, 8 megabytes is tiny. We hear about OS/2 needing 2 megabytes to be functional; what about the applications that will need 6 mega- bytes or more? • Stratospheric prices for high-perfor- mance random access devices must fall. When we see a 1-gigabyte hard disk drive with 24-millisecond (innermost to outer- most cylinders) seek times for under $1500, then the personal computer mar- ket might afford cost-effective paging de- vices. Until then, paging will be an ex- pensive and slow toy. • Finally, and perhaps most important, who will manage the "deskframes"? Then there is the question of the perfor- mance adjustments and required mainte- nance (like backups and spool cleaning). Soon we'll have to redefine what the terms mainframe, mini, and micro mean. Will there be pico and femto ma- chines, perhaps? You can bet there will always be a niche for the single-user, sin- gle-task operating system running on nonvirtual hardware. We all need to keep in mind the hardware and software prob- lems that have already been addressed and occasionally solved in the main- frame world. Let's not make the same mistakes in the micro world. Jonathan Allan O 'Fallon JL LETTERS POLICY: When submitting a let- ter for publication, double-space it on one side of the paper and include your name and address. Express your comments and ideas as clearly and concisely as possible. We can print listings and tables along with a letter if they are short and legible. Because we receive hundreds of letters each month, we cannot publish all of them. We cannot return letters to authors. Gener- ally, it takes four months from the time we re- ceive a letter until we publish it. Vindication at Last I was fascinated to see that your October 1987 issue (which I received in mid- March) has finally caught up with my book 2001: A Space Odyssey. It is still not widely known in the com- puter industry that HAL stands for heu- ristically programmed algorithmic com- puter, even though I spelled this out carefully in Chapter 16 of my book. I've spent 20 years trying to disown the leg- end that HAL is derived from IBM by transposing one letter, and I even had my characters in 2010: Odyssey Two contra- dict this canard (see Chapter 35). So I'll be happy if you can help me stamp it out! Arthur C. Clarke Colombo, Sri Lanka Learning Difficulties Thank you for publishing Alex Lane's nice review of Trilogy ("Trilogy: A New Approach to Logic Programming," March). It is difficult to review a new language, and Lane has to be compli- mented for describing Trilogy to your readers quite well. On the other hand, in the short time he had for the review, he did not quite manage to understand the difference between the scopes and pro- gramming styles of Prolog and Trilogy. A substantial part of Lane's review concerns the comparison of Turbo Pro- log 's and Trilogy's stack/heap over- flows. Using the Tower of Hanoi bench- mark, Lane overflowed Trilogy's stack with 10 rings, while Turbo Prolog exe- cuted OK. The main predicate in Prolog (example #55 from the Turbo Prolog manual) is as follows: hanoi (l,A,B,C) :-inform(A,B) , ! . hanoi (N,A,B,C) :- Nl=N-l,hanoi(Nl,A,C,B) , inform(A,B) , hanoi (N1,C,B,A). The predicate inform(A,B) just prints disk moved from A to B. Lane translated this program into Trilogy as follows: pred Hanoi (n: 1 here} Hanoi(n-l,a,c,b) & Inform(a, b) & {Lane called Hanoi(l,a,b,c) here] Hanoi(n-l,c,b,a) I've modified both programs slightly here so they can be directly compared without affecting their substance. Now Trilogy executes 10 and 11 rings but overflows on 12. Turbo Prolog doesn't overflow. Unfortunately, Lane did not realize that the programs were not equivalent. Note the cut operator (!) in the Turbo Prolog version. Whenever the recursion comes down to 1 (and it comes there 2048 times for 12 rings), the cut removes the so-called choice point from the stack. Lane's Trilogy program leaves all the choice points on the stack. In other words, Lane has explicitly commanded Trilogy to overflow. If he wanted an equivalent comparison, he should have removed the cut ( ! ) from the Turbo Pro- log program— then he would have over- flown its stack/heap with 12 rings as well. Cuts are features that violate the logic of Prologs. They were introduced as quick hacks in order to improve the exe- cution times. Prologs are sorely missing the IF . . . THEN . . . ELSE constructs re- quired here. Trilogy does not contain cuts, and Lane should have used an IF. . .THEN.. .ELSE: procHanoi (n : < I , a :