Microcomputer Newsletter August 1985 Volume 1, Number 10
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f'r ':' () .-::l.-=3~ l"f\ Microcomputer Newsletter August 1985 volume 1, number 10 CONTENTS Discount Program News Once again there are several changes and additions to the Discount Program News University Microcomputer Discount program: Zenith is now (new arrivals at the Micro HelpLine, shipping one of the products we described in the July new Hewlett-Packard prices, Zenith newsletter, Hewlett-Packard prices have changed, we have Z-148 now available) ................... 1 Hewlett-Packard's new UNIX machine at the HelpLine, and we also have AT&Ts UNIX PC (the 7300) available for your Review: Turbo Pascal Version 3.0 for the IBM PC Family inspection at the Micro HelpLine. Here are the details: (the latest version of an inexpensive, high-performance Hewlett-Packard News Pascal compiler) .................•......2 Prices for Hewlett-Packard equipment available through the discount program have decreased. Here are some Updated MacWrite representative prices: (hints for using Version 4.5 of MacWrite) .......•.....•......•........... 4 2686A LaserJet Professional PC printer with RS-232 interface, toner cartridge, Advice: Ask Dr. Micro 10-point Courier font $1999 (mysteries of the LaserWriter explained, discovering hidden 225C ThinkJet printer with parallel interface $ 284 225D 1 microcomputer labs on campus ) ... 6 ThinkJet printer with serial interface $ 284 l 7470A001 2-pen plotter, RS-232 interface $ 627 7475A001 6-pen plotter, RS-232 interface $1085 AND MORE ..•...................... 45710A HP Portable microcomputer $1714 l 45650B Touchscreen Personal Computer, 256K I f' memory, two 3.5" floppy disk drives f (710K capacity), two parallel ports, The Microcomputer Newsletter is one HP-IB port, MS-DOS 2.11 $1999 published by the University Computer Center Microcomputer We now have Hewlett-Packard's new machine (the Integral) Systems Group. at the Micro HelpLine. This transportable machine runs The Microcomputer· Newsletter was HP-UX (Hewlett-Packard's version of the UNIX operating system). The UNIX kernal is built into Integral's ROM along Ii produced with an Apple Macintosh 1 running MacWrite, MacDraw, and with P.A.M. (a window manager that acts as a shell between ReadySetGo software and printed you and UNIX). The Integral's display is a flat-panel on the Apple LaserWriter. electroluminescent screen and there is an ink-jet printer built I into the system. The complete system weighs 25 pounds and I The University of Minnesota is very compact. When closed the Integral is about the size of adheres to the principle that all a sewing machine. Here is what it all costs: ! persons should have equal I' opportunity and access to facilities 98807A Integral, 512K memory, one 3.5" disk drive, :! in any phase of University activity without regard to race, religion, electroluminescent display, keyboard, built-in color, sex, national origin, ThinkJet printer, one HP-IB interface, two handicap, age, or veteran status. HP-IL ports, two expansion slots $2858 82925A 256K memory card $ 398 Copyright e1985 by the University 82927A 512K memory card $ 856 of Minnesota 82919A RS-232 interface card $ 112 (Discount Program News continued on page 7) Review: editor ,Y~U prefe~. To customize the editor, you run Turbo s mstallation program and specify the Turbo Pascal 3.0 for ~eystrokes to move the cursor up a line, down a the IBM-PC family lme, and so on. The Turbo editor is an in-memory editor. This me.ans that all the text you are working with must We have been using the new version of Turbo fit .m ~emory at the same time. That's why the Pascal (3.0) ~or the ffiM PC, XT, AT, and editor 1s very fast. However, this also means that ffiM-compauble ~crocomputers for two months. there are limitations to the size of the flle that can Based on ~ur expenence, we enthusiastically be edited. In the Micro Group, we have rarely endorse this product. Turbo is an excellent found thi~ size limitation to be a problem. If you package at a very low price ($42 at the Minnesota are ~or~g on an extremely large program, the BookCenter). Turbo Pascal is a fast and efficient solution 1s to use the compiler Include directive. Pascal compiler with an integrated full-screen It provides the ability to split your program into editor. (A compiler is a program that takes Pascal smaller ~OO;ules and put the modules back together program statements and translates them into code at compile-~e. The Include facility also aids the computer can execute.) program clanty; Commonly used subprograms, once tested and debugged, may be kept as a library The Turbo Pascal system requires 39K of disk of flies that can be included in any other program. space. Other Pascal compilers such as Microsoft Pascal require over 300K of disk space. There are If the compiler detects syntax errors in your oth~r. advantages t~ Turbo's compact size in prog~ as the program is being compiled, Turbo a~ditlon to the obv10us one (using less space on automatically ~turns you to the editing mode, with ~sk). Turbo's compiler and editor reside together the cursor positioned on the program line which m memory, so moving from the editor to the caused the error. Thus, changing and recompiling comp~er during pro~am development is programs is fast and painless. These features make ex~ep~onally fast Smce Turbo resides in memory, Turbo an excellent choice for learning Pascal. sw1tching from the editor to the compiler does not requir~ a disk access. Using Turbo you can enter Deviations from Standard Pascal the editor, create the source text for a program exit Turbo accepts almost all standard Pascal ~e edi~or, compile the text in memory, and ' statements, as described in the Pascal User Manual lffiffiediately return to the editor if an error is and Report by Jensen and Wirth, so it is possible found. to write highly portable code. However there are some deviations from standard Pascal. The most Turbo Pascal is a menu-driven environment· when notable ones are: using Turbo, you have a menu of command~ at y~mr disposal. You select a command by typing a 1.) The standard Input/Output procedures Get and smgle letter. Each menu item is displayed as a Put are not implemented. Instead, the Read and word or phrase, with the key letter highlighted on Write procedures have been extended to handle all the screen. From the menu you can edit or compile 110. This is the most significant deviation, and it is your program, change the default disk drive view actually an improvement over the standard Pascal. an~ chang~ directories, or change compiler ' Of course, it's time consuming to convert Pascal options. Smce you rarely need to leave the Turbo code containing Get and Put to Turbo Pascal and environment, program development is simple it does diminish the portability of the code. But we fast, and efficient. ' have found that using Turbo's more generalized Read and Write statements does have its rewards. The Editor Many programs become simpler in the process. The Turbo editor commands are a subset of the WordS tar commands. Because the Turbo editor is 2.) The GoTo statement is restricted to intended for program development, it does not transferring control only within the currently active include word processing features such as block. word-wrap, underlining, boldface, italics, or paragraph reformatting. If you are already 3.) The Page procedure is not implemented. comfortable with an editor other than WordStar, (Turbo Pascal continued on page 3) you can customize the Turbo editor to resemble the Page2 (Turbo Pascal continued from page 2) specified angle result in lines that correspond to the 4.) A program may not pass procedures and turtle's path. functions as parameters to other procedures. This is not unusual, since almost no microcomputer Overlay Facility version of Pascal has this feature. Turbo has a simple overlay facility. The overlay system allows you to create programs that are Extensions larger than can be fit into the computer's memory. Turbo contains several extensions to standard You preface procedure and function declarations Pascal. The most useful are strings, easy access to with the word overlay and the compiler will keep the operating system, graphics, and the overlay track of them. When you execute your program the facility. overlay flies will be read into memory as needed. Strings License Agreement Turbo has implemented strings (a string is a Borland has a no-nonsense license agreement The dynamic-length array of characters). This license agreement says, "This software is protected non-standard feature is essential in a compiler, by both United States Copyright Law and since strings are almost indispensible for most International Treaty provisions. Therefore you programs. In fact, nearly all microcomputer must treat this software just like a book with the versions of Pascal have string extensions. Turbo following single exception. Borland International strings and standard procedures for manipulating authorizes you to make archival copies of the them closely resemble those found in UCSD software for the sole purpose of backing-up your Pascal. The maximum length is declared with the software and protecting your investment from string. Strings may not exceed 255 characters in loss." length. By saying "just like a book" Borland means that Accessing the Operating System this software may be used by any number of With Turbo you can access the operating system people and may be freely moved from one without using assembly language. For example, computer location to another so long as there is no there are procedures for graphics, input/output possibility of it being used at one location while redirection, accessing and changing file it's being used at another.