CP/M & Pascal P-system, UCSD Pascal, related efforts

Most recent revision dated Jan 25 2013. Corrections appreciated. This material was moved from my S-100 and CP/M Web page of Web links.

An item in eBay about UCSD Pascal caught my attention in July 2004. I did some Web searching and found surprisingly LITTLE about UCSD Pascal, other than some references to the history and legacy of the product. Notibly: 1) the P-code system is a predecessor of sorts to Java and 2) Delphi is a kind of descendent of Pascal. However, almost NO archive and content on the Web in 2004, discussed the actual UCSD compilers or the P4 interpreter. I did find one software source link of sorts:

Authors Steven Pemberton and Martin Daniels have posted on Pemberton' Web site Pascal Implementation, a manual with Pascal source code for a P4 interpreter. The book was written by Steven Pemberton and Martin Daniels to support a course on Pascal compiler design. The home page of Pemberton provides some context for this work, converted to HTML and available via the link. Another page which refers to this work and "standardizes" it is: Scott A. Moore's brief on P4 and UCSD Pascal on his Web site. A Web search on "UCSD Pascal" will find a number of histories of that implementation and subsequent distributions of it.

The UCSD Pascal system was its own operating system. Clarence Wilkerson, a math professor at Perdue University, came up with a CP/M BIOS version. that is, the P-code interpreter used a CP/M BIOS to interface to the hardware. Check this link to his posted work at Perdue's Math Department Web site

A major newsletter of the early Pascal era was the "Pascal Users Group Newsletter", published from 1974 through 1983. A set of these has been scanned and PDF'ed, with permission apparently, and is available at this link on Scott Moore's Web site at moorecad.com. He offers Moore/CAD and some Pascal products, and his site includes a lot of Pascal material.

I also came across the Borland museum, which offers some of its early Turbo Pascal and Turbo C software. They are "free of charge...for personal use only" but still have "copyrights in force". (But see what happened by late 2008 to the Borland Museum.)

There are many other sites which either celebrate Pascal, archive Pascal, or support Pascal use. Look around, it's amazing!

The following was posted in Usenet newsgroup comp.compilers on 24 Feb 2006:

>> From: HansO 
>> Newsgroups: comp.compilers
>> Subject: UCSD Pascal I.5 sources available at UCSD
>> Date: 24 Feb 2006 13:17:28 -0500
>> Members of the Yahoo group devoted to UCSD Pascal
>> http://groups.yahoo.com/group/UCSDPascal/
>> (David Barto is the person to thank for that)
>> have convinced UCSD to publish the sources of UCSD Pascal I.4 and I.5.
>> The sources contain the complete set of sources compiler, operating
>> system, editor, linker, librarian Pascal and interpreter assembler
>> source etc.
>> The direct location to download the sources (also mentioned on my
>> website now) is:
>> http://invent.ucsd.edu/technology/cases/1995-prior/SD1991-807.htm
>> This software is nearly 30 years old!  The relevance is mostly for
>> understanding the history of programming languages (structured and
>> modular programming), compiler construction (UCSD Pascal is based on
>> the recursive descent down single pass P2 Pascal compiler made by
>> Niklaus Wirth and his brilliant group at the ETH Zurich), operating
>> systems written in a higher level language and interpreter based
>> virtual machines.
>> Hans, http://www.hansotten.com

In June 2008, I found the Pascal Users Group Newsletters in PDF form on-line, at "morecad.com", a private site with resources on "standard" PASCAL.

Z80-SIM developer Udo Munk has included more UCSD Pascal materials on his emulator Web site. By Aug 2007, he now has UCSD Pascal system I.5 and II.0 for the Z80 running under his emulator. By Aug 2008, he included system 3; and system IV, the last "version" released and from the former commercial vendor.

By Aug 2008, I found a number of Web resources for UCSD Pascal or p-system Pascal. This archive of UCSD history and release information by the successors of its first developers at the University of California is informative. The current Wikipedia entry for UCSD Pascal is a reasonable summary.

Late in 2008, the subject of Turbo Modula-2 came up. Modula was developed subsequent to Pascal by Wirth, and likewise was initially developed as interpreted "M-code". The Borland product "Turbo Modula-2" was a Z80 and CP/M based product of Borland for a brief time, before its developers spun off to form their own company. Later they developed other products including "Clarion", a database product. The company became "Clarion" and was bought and sold and eventually became part of The whole story and the apparent current owners of the original Z80 Modula-2 product are discussed on this Web page.

In July 2010, I was contacted by Pascal Microengine owner M. R. Wigan. On his Web site he discusses the history of Western Digital's hardware chipset for their hardware and product implementation of UCSD Pascal. This same chipset was used for microcode for DEC's LSI-11 and other such products. Wigan also has a S-100 cards system with the WD UCSD chipset, made by Digicomp Research of Ithaca NY, using a local company (Ithaca Intersystems) for their S-100 front panel and cabinet. A later version of this Digicomp Research produte was used to develop an early Ada compiler. Digicomp is still in business and has a modern Web site at digicomp.com.

In Jan 2013, I found a set of UCSD P-System with Pascal, Version II disk images on the Heathkit Web site of Mark Garlanger.

Contact information:

Herb Johnson
New Jersey, USA
To email @ me, see see my ordering Web page.

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