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Pascal. (The Attach BIOS material was described and augmented in the Fall 1981 Apple Orchard.) Well and good: now what's missing from the Apple II Pascal? Currently, a program is limited to 16 segments or units, and the System Library can contain only 16 segments. That's an effective run-time total of 32 units or segments. These limits are at least inconvenient, and ofttimes more than that(!). The distinction between regular units, which count against a program's segment limit and must be explicitly linked to their host; and intrinsic units, which must be in a system library but do not have to be linked, seems arbitrary and annoying. As I develop more and more generally useful units, and use these units to break up my programs into logical pieces, I keep running up against these limits. That means a lot of library management, using this library or boot disk for one program, and that one for another, etc. I'd rather be designing and coding! It would be very nice indeed to eliminate regular units, making all units intrinsic, and eliminating the need for linking. It would also be nice to raise the limits on both the size of the System Library and the size of programs; or to introduce a program library facility by which a program could have its own library of intrinsic-type units. Although the EXEC feature is useful, full 1-0 redirection capabilities would be nicer and even more useful. What do I mean? Consider the following situation, which leads to a question I am often asked (so there must be others who would like this feature too). You have written a program which outputs to the screen. Next, you would like to run the program and have its output directed to a printer or a disk file. In effect, you would like to pass an output file name parameter to your program when you X( ecute the program. Can you do it? No ... and yes. That is, you can't pass a file name that way, but, as I'll show in a future article, you can redirect output using a trick or two to achieve a similar result. The point here is that the feature is definitely not present at the operating system level. Finally, there are certain software tools and programming aids that only Apple the Company can provide and which I feel they should provide, even if at a (moderate) cost. I've no doubt they must have and use these tools for their own development work; after all, we have been told that Pascal is Apple's chosen in-house development language. The tools are such that only Apple can assure they will remain useful as the operating system (and the Apple II) evolves. One such tool is the screen control unit, a unit to provide terminal independent screen operations including CLEAR SCREEN, ERASE LINE, text windowing, etc. If nothing else, such a unit would ease the problem of transporting Pascal software from Apple II to Apple I I I, to IV, or whatever. Another is a unit with routines to access and modify the system date (tied to a clock if present), the default volume name (the Prefix volume), and disk directories including file dates, wild card searches, etc. For one thing, this would grant every program that needs it the ability to list directories. Another tool which could be provided is a unit to convert strings to integers or reals, and back again. The built-in facilities for doing this are a bit flaky, and in many cases not very friendly. (See Paul Sand's article elsewhere in this issue.) The only fail-safe way to enter numeric data now is to allow the user to enter string data, ana then convert the string to the desired type. Apple the Company could help by supplying this stuff and seeing to it that the routines take advantage of how real data is represented on the host machine, including the number of bytes used to represent reals. Apple I I I Pascal There are some significant differences between the Apple II and Apple I I I Pascal systems, because Apple I 11 Pascal is an improvement and a strict superset of Apple II Pascal. With only a few minor modifications, like changing control character values to make MISCINFO compatible with SOS, Apple II Pascal will run on the Apple I I/. Moving a program from the I 11 to the II, however, doesn't come as easily. One difference is that SOS-Apple 111 Pascal can maintain hierarchical directories. The Apple II cannot, of course, and any programs which rely on this feature will not be portable. A major strength of the Pascal language is the ability and requirement to classify variables by types. All variables must be declared to be of a type, and that identification specifies its permissible values and the operations that can be performed with it. Unfortunately, this strength turns out to be a hindrance when trying to develop libraries of general procedures to operate on arrays. Apple 111 Pascal has provided a partial solution to this dilemma with the inclusion of two new datatypes, "bytestream" and "wordstream," which can be used to type variable parameters in procedures. To illustrate, consider the following Apple 111 example: PROGRAM example; VAR a b ARRAY[1..100] OF INTEGER; ARRAY[25 .. 74] OF INTEGER; FUNCTION sum (VAR data : wordstream ; n : integer) : INTEGER; VAR x, i INTEGER; BEGIN x : 0 FOR sum END; x· ' BEGIN WRITELN WRITELN END. 0 to n DO x (sum (a , 100)); (sum (b, 50)); x data[iJ; 76 Apple Orchard
GREAT LAKES DIGITAL RESOURCES IS PROUD TO ANNOUNCE... Choosing the right RAM board for your Apple II Computer is easy as 1, 2, 3. 1. The 64K and 128K RAM boards from Legend Industries are the original large memory boards for the Apple. They a re the m ost widely used a nd best tested. The 64KC and 128KDE are far more versatile than any of the le sser capacity boards that you can buy for the Apple 11. For example - Up to 145K VISICALC models can be created using the VC PLUS program. Disk Emulation, Memory Master, and many application programs use these RAM boards. 2. Legend Industries is dedicated to providing more programs that use the 64KC AND 128KDE RAM boards. When you write a program that is used as a part of the product or is offered as a commerc ial product from Legend Industries they will refund in full the purchase price of the board. This policy a lso applies to providing patches to commercial software so that they can use the expanded capacity of the 64K and 128K RAM boards from Legend. 3. The warranty on the 64KC and 128KDE has been extended to 1 year. It has been a year since the 64K RAM board was introduced by Legend Industries. This experie nce has p roven our confidence in the product and the technology tha t we introduced. AFTER CONSIDERING THESE POINTS CHECK THE PRICE 64KC - 64K DYNAMIC MEMORY BOARD FOR THE APPLE II DISK EMULATION SYSTEM - 2 64KC RAM CARDS WITH DISK EMULATIO N SOFTWARE, MEMORY MASTER, AND VC PLUS 128KDE SOFT DISK - 128K DYNAMIC MEMORY BOARD WITH DI SK EMULATIO N SOFTWARE, MEMO RY MASTER, AND VC PLUS VC PLUS- CREATES UP TO 145K WORKSPACE IN VISICALC DISK EMULATOR 2.1 - SIMULATES FAST DISK DRIVES ON THE APPLE II (REQUIRES 1-6 64KC) PASCAL SOFT DISK EMULATOR - SIMULATED FAST ACCESS DRIVES FOR APPLE PASCAL l.l (REQUIRES 64K OR 128KDE) LEGEND LCG 1 & 2 - LOWER CASE GENERATOR FOR APPLE II MEMORY MASTER 1.1 - MEMORY MANAGEMENT FOR THE APPLE II $349. $700. $750 . s 34.95 ' s 49.95 s 49.95 s 49.95 s 34.95
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Buy Five Megabytes Of Winchester St
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Vol. 3 No. 2 May-June 1982 Entire c
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Expand your Apple into a full CP/M
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Page 30 and 31: FILE CABINET STOFFER When FILE CABI
Page 32 and 33: 490 PRINT D$"MONCIO" 500 REM CREATE
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Page 36 and 37: 800 NEXT K 810 NEXT M 820 PRINT : I
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Page 48 and 49: "E .c "' ~ 0 QI n. ~ ID "" - D0 06
Page 50 and 51: Sl20 * ~ENTS. ENTRY "TAB" IS USED S
Page 52 and 53: EDUCATIONAL USES OF THE COMPUTER by
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Page 58 and 59: here is: Don't always expect books
Page 60 and 61: Based on the above discussion, we w
Page 62 and 63: SEVENTH ANNUAL COMPUTER FAIRE by Am
Page 64 and 65: make it possible for the user to us
Page 66: effort to develop it. But the Frank
Page 69 and 70: If you read last issue's installmen
Page 71 and 72: . 1111111111111 :-11111111111111111
Page 73 and 74: TOGETHER, LOCKSMITHT; THE INSPECTOR
Page 75 and 76: ' 8 © Copyright 1981, QUAD Systems
Page 77: WILL THE REAL APPLE PASCAL PLEASE S
Page 81 and 82: TASC: The Applesoft Compiler. It tu
Page 83 and 84: P1'ESidE11t's MEssatE Ken Silverman
Page 85 and 86: a=: w :::c u -.... U) ;: .. .. a=:
Page 87 and 88: well as drivers for use with VisiPl
Page 89 and 90: - _..:::- =- - :::: Introducing Dat
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