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Computers Shouldn't Be Limitations Advertising & Distribution a Handicap Is a Limitation

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Computers Shouldn't Be Limitations Advertising & Distribution a Handicap Is a Limitation .. No. 48 July-August 1989 $3.95 T HE MICRO TECHN I CAL J 0 URN A L Tools For The Physically Impaired What's important to people who have handicaps? We asked them. (Their responses may surprise you.) The Adventure Begins page 8 Dallas Vordahl demonstrates what you can do with a computer, a mouthstick, and a very limited amount of head motion. Writing Software For page 16 The Blind Don' t exclude the blind from your next software package. File Transfer Via The page 20 Parallel Port The LIMBO Project page 28 Build a maze-running robot. And More ... Debugging A Processor page 44 Growing Your Own page 66 Software Business Great SOGs page 83 And Much, Much, More 07 a 7447019388 3 U[J!]£?[jj) J/@[J!]£? !fJ©llfU/5Ju O[jj)(]@ (j] /JJ@r:'.JQ£?fj[J!]O /LfI1@@£?(JJ(]@£?J/ (j][jj)@ @[jj)@]O[jj)QQ£?O[jj)@] (]@@ODDD Introducing ... The PC-LabCard Family Only from HSC Electronic Supply Digital 1/0 and Prototype Development IBM PC/XT/AT and it's Counter Card compatible models are moving into Card Industrial/Laboratory applications at • 32 Digital Input Channels • Large breadboard area (3290 holes) - TTL compatible an increasing rate. The reasons for • Independent memory and I/O address - Low loading: 0.2 rnA at O.4V input this include their price/performance decoders built-in • 32 Digital Output Channels ratio and short user learning curve. • Memory and I/O ports are jumper - TTL compatible PC-based data acquisition boards selectable - Driving capacity: Sink 24 rnA, are now taking the place of the • All bus signals are buffered, marked, source 15 rnA and ready for use • Intel 8253 Timer/Counter traditional data loggers or recorders - 3 channels of timer/counter which cost several times more. PCL-750 .................................... $74.00 - Breadboard area for flexible user configuration "PC-LabCard" is a family of add-on cards to turn your PC into a PCL-720 ............................... $160.00 high performance data acquisition/ testing system at an attractive price. It includes not only the hardware cards, but also the software, accessories and application support packages which come together to make a thoughtful solution to your PC-based automation needs. QuickMod V2.0 Compiler. .. Just think what the two of you can do. You can make software engineering faster And when you need more horsepower. and easier than it's ever been before. The you can move into the Professional high performance QuickMod by Stony Modula-2, Stony Brook's fully optimized Brook delivers a compilation speed that compiler. You get the same high productiv­ exceeds 15000 lines per minute on AT ity environment with code generation machines. And it's a true two-pass, and flexibility you can't find in any other Modula-2 compiler with an intelligent product in the industry. environment that determines dependen­ Stony Brook-we design our products cies automatically and builds your pro­ specifically to improve developer perfor­ gram with a single keystroke. You do little mance. And we. know software engineer­ more than enter the program text-then ing. Put us to work for you. let Stony Brook handle the work load. SOFIWARE Call us direct and we'll mail product QuickMod is more than a supercharged information to you within 24 hours. Your Partner compiler-it is a fully supported package in Software Development backed up by a text editor, a linker, a 800/624-7487 library manager, a symbolic debugger and a runtime library that offers more func­ 805/496-5837 ~.,aJif~~~~~ational tionality than anything else on the market. 805/496-7429 Fax All for $95. Versions available for DOS Reader Service Number 152 and OS/2. 187 East Wilbur Road, Suite 9, © 1989 Gogesch Micro Systems. Inc. Thousand Oaks, CA 91360 MICRO CORNUCOPIA, #48, July-August, 1989 1 §JERTI01U§ ]])JEIB1UGGRNG at a RJEA§ONAIBJLJE PRTICJE All the speed and power of a RUN CODEVIEW hardware-assisted debugger IN~~LY8K! at a software price I~~~~.. Soft-ll Code View is a great integrated debugger, but it uses over 200K of conventional memory. Hardware-level break points MagicCV uses advanced features of the 80386 REAL-TIME break points on memory locations, memory ranges, microprocessor to load Code View and symbols in execution, I/O ports, hardware and software interrupts. More extended memory. This allows MagicCV to run powerful break points than ANY software-only debugger on the Code View using less than 8K of conventional market. Soft-ICE gives you the power of an in-circuit emulator on memory on your 80386 PC. your desk. Don't let 640K be your limit! Break out of hung programs If you are closing in on the 640K limit and would With a keystroke - no external switch necessary. Even with like the power of Code View, MagicCV is for you. interrupts disabled. Don't let the debugger hide the bug! Breaks the 640K barrier Even if you're not closing in on the 640K limit, Soft-ICE uses ZERO bytes of memory in the first 1MB of address running Code View with MagicCV makes your space. This is especially useful for those subtle bugs that change debugging environment much closer to the end when the starting address of your code changes. With Soft-ICE user's program environment. You can use your code executes at the same address whether the debugger is Code View to locate subtle bugs that only occur loaded or not. when there is plenty of free memory, or those difficult bugs that only occur when your program Works with your favorite debugger is running with a couple of TSRs loaded. Soft-ICE can be used as a stand-alone debugger or it can add its powerful break points to the software debugger you already use. How MagicCV works You can continue to use your favorite debugger until you require MagicCV uses the 80386 to create a separate Soft-ICE. Simply pop up the Soft-ICE window to set powerful virtual machine for CodeView. MagicCV uses real-time break points. When a break point is reached. vour between 4K & 8K of conventional memory as a debugger will be activated. - . ~ bridge between the DOS environment and CodeView. Solve tough systems problems too Soft-ICE is ideal for debugging TSRs, interrupt handlers, self MagicCV is easy to use booting programs, DOS loadable device drivers, non-DOS If you are a Code View user, you already know how to use MagicCV too. Just type MCV instead of operating systems, and debugging within DOS & BIOS. Soft-ICE is also great for firmware development because Soft-ICE's break CV; everything else is automatic. points work in ROM. Save $86 How Soft-ICE Works Soft-ICE uses the power of the 80386 to MagicCV $199 surround your program in a virtual machine. Soft-ICE $386 MagicCV This gives you complete control of the DOS environment, while Soft-ICE runs safely in Buy Both and Save $861 with Soft-ICE protected mode. Soft-ICE uses 80386 CALL TODAY Using Soft-ICE with Code­ protected mode features, such as paging, I/O (603) 888 - 2386 View gives you the features privilege level, and break point registers, to or FAX (603) 888 - 2465 necessary for professional provide real-time hardware-level break points. level systems debugging. 30 day money-back guarantee Visa, Master Card and AmEx accepted MagicCV and Soft-ICE can "Soft-ICE is a product any MS-DOS work in concert with Code­ developer serious enough to own a r"u - r~lEGl\ TECHf"OLOGIES View to provide the most 386 machine should have." powerful debugging Dr. Dobb's Journal -May 1988 P.O. BOX 7607· NASHUA, NH 03060-7607 platform you will find anywhere. Both require 80386 AT compatible or IBM PS/2 Model 80. MagicCV requires at ~••• R.ea.deirliseir,Viiice.Niiuiiimiibeiir.lil0 ..... least 384K of extended memory. CodeView is a trademark of Microsoft Corporation. 2 MICRO CORNUCOPIA, #48, July-August 1989 THE M I C R 0 TECHNICAL JOURNAL MICRO CORNUCOPIA JULY/AUGUST 1989 - ISSUE #48 FEATURES COLUMNS Dallas Vordahl 8 The Adventure Begins 44 86 World How does a quadriplegic declare independence? It's not easy, but with a mouth stick and a computer, almost anything's possible. 50 C'ing Clearly Debee Norling 12 Selecting A Talking Computer For A Blind Friend There are a lot of well-meaning people who'll help you pick out a computer for 60 ShareWare a blind friend. Debee's a lot more than well-meaning. Debee Norling 64 Culture Comer 16 Writing Software For The Blind Debee suggests some not-sa-obvious things you can do to make your software easier to use for the blind (things all your customers will appreciate). 66 On Your Own Bruce Eckel 20 File Transfer Via The Parallel Port 77 Units And Modules Tired of moving data one bit at a time? Think there might be a faster' way? A much faster way? There is, and here's everything you need to do it. 83 SaG Information Bob Nansel 28 The LIMBO Project-Part Two Bob begins his mechanical rllg rat. (And you thollght you'd be left in limbo.) 76 CP/M Notes Chris Howard 90 Tech Tips 34 PCX Compatibility As we create fancier graphics we place more demands on our standard graphics file formats. Can a standard format support change? FUTURE TENSE Karl Lunt 38 A 68000-Based Multitasking Kernel As long as you're going to design your own ROM it might as well do two 86 Tidbits things at once. Right? Jack Crenshaw 96 Last Page 80 The Very Early Days Of Computing Jack describes NASA's first multiprocessor.
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