80-Bus News


July–August 1983 · Volume 2 · Issue 4

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Letters to the Editor

Re. COMPAS Review

I saw that COMPAS was reviewed by Doctor Dark (your graduate in Voodoo medicine?) in vol. 2 iss. 3, and although I am always pleased to see our products mentioned in articles, in this case I was less excited, since the product reviewed is COMPAS version 1, and not version 2, which is a far better package.

As opposed to COMPAS 1 and Hisoft Pascal, COMPAS 2 is a superset of Standard Pascal, i.e. it supports all features of the standard language, plus many more. The extensions that are most noteworthy are dynamic strings, random access files, structured constants, include files and, in the latest version (called 2.20) also overlays. All extensions are carefully thought out, and to a large extent are compatible with other well known Pascal systems, such as UCSD Pascal and Pascal MT+.

Programs written in COMPAS 2 can be distributed with no royalties payable. We realise that the terms set forward in the COMPAS 1 license agreement were a bit harsh, not to mention the fact that they were impossible to implement. Therefore there are no royalties on programs written using COMPAS 2.

I feel that COMPAS 2 is the ideal package for anyone who wishes to learn about Pascal since it supports the full standard, it is also ideal for experienced programmers since the extensions make this a very powerful implementation of Pascal indeed.

Anders Hejlsberg, Polydata, Denmark.

MBASIC on Disk

I read with great interest the article by Dr. Coker in the last issue of 80-BUS News and it is obvious that he has looked at his BASIC in great detail but has not done sufficient programming in it to find the error in his use of the substitute REM statement. In particular he will find that while you can use the apostrophe (27H) either at the start of the line or in the middle, if used in this latter position it is necessary to include a colon to seperate it from the previous command or that program could crash as BASIC will not know where to stop interpreting and treat the remainder of the line as a REM statement.

His second comment that MBASIC is regularly updated may have been correct but reading the trade press one is lead to believe that MBASIC-80 is a casualty of the CP/M versus MSDOS war, and that Microsoft will not be supporting it for CP/M-80 in the future.

Since the 80-BUS is essentially a Z80 bus which runs CP/M and we are not too interested in “foreign” operating systems such as MSDOS, what is needed for the next 10 years is a UK supported BASIC, starting with the core instructions of MBASIC and having extensions to cover the following:

(a) Use of full Z80 instruction set

(b) Include additional commands such as cursor addressing, clearing screen, reverse video and other terminal attributes

(c) Enabling the BASIC interpreter or compiler to address more than one 64K page of memory where it is available

The principle reason why so called 16 bit machines have gained in popularity is because most of the software available to run under CP/M uses only the 8080 instruction set and not the enhanced instruction set of the Z80 which we all know and love!

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