ef@karl.tools.uucp (Edgar Fuss) (05/26/90)
This is the most interesting debate in comp.lang.pascal since months! Anybody knowing details about III.x p-Code (the Microengine one's)? Edgar
randy@m2xenix.psg.com (Randy Bush) (05/27/90)
milne@ics.uci.edu (Alastair Milne) writes: ( some smarmy remarks which we can hope were made in jest :-) Yes, Version IV was mostly SofTech's, though done by many of the same folk from KB's group. I have no idea what Eli and the crew in Brooklyn have done in the interim, though; and would love to hear about changes to the pmachine architecture if folk on the net happen to know. The canonical floating point was done at SofTech, to my recollection, and the byte-sex independence definitely was, and came in with IV.0. The portability these provided never was useful in the marketplace, and had a distinct cost in performance; a lesson there. I have a rather extensive collection of the architecture and internal documentation for SCUD [1.3..IV.1]. The history and changes are rather interesting. What I would rather have is a copy of Jerry Barron's "Pascal: the Language and its Implementation", which I did not manage to snag before it went out of print. [John Gough, who is visiting, just had the nerve to tell me he picked up a copy on remainder for $4, the cad!] If anyone sees a spare copy of this gem, I would really love to get it. > SYSTEM.PASCAL has some host-dependent units, like REALOPS, and perhaps one > or two others I don't remember. I think you're correct there. As SofTech's San Diego operation faltered, I was drifting onward through Violation Systems's implementations which were more based on enhanced (for Modula-2) II.1 architecture, a la Apple Pascal. > The fun we could have discussing different p-System versions! Anybody > want to mention version III? For those having Pascal MicroEngines (the III.0 system) in the closet, I just happen to have the hacks and software to actually make that a usable machine. Darn shame that WD bungling killed it; for its day it was quite useful. It was the first SCUD with tasks, semaphores, and events. And I think you are correct in that the interpreter had to handle the ready and semaphore queues, though the code is not too large (just hard to debug). The real turkeys in SCUD interpreter hacking are sets, floating point emulation, and I/O. Yes, Urs Ammann did the Zuerich P2 compiler. But the P2 p-code assembler and interpreter has Kathy Jensen's and NW's names on it. I actually have source for all this stuff as well as a collection of the related papers of the time (all in hardcopy unfortunately). But I believe that Barron's book is by far the best overview. Nice to see actual discussion of that stuff here as opposed to how to get turbowhatzit (tm Pat Terry) to handle Int42. I am told that turbowhatzit has finally discovered UNITs, a decade later, wow. randy -- ..!{uunet,qiclab,intelhf}!m2xenix!randy randy@psg.com randy@m2xenix.uucp
randy@m2xenix.psg.com (Randy Bush) (05/28/90)
ef@karl.tools.uucp (Edgar Fuss) writes: > This is the most interesting debate in comp.lang.pascal since months! You mean there are other people who don't run turbowhatzit (tm Pat Terry)? > Anybody knowing details about III.x p-Code (the Microengine one's)? Yes, or at least I used to, and still have the internals documentation. Are you trying to use one of the MicroEngines? If so, send email and be patient. I will be out of the country for two weeks. -- ..!{uunet,qiclab,intelhf}!m2xenix!randy randy@psg.com randy@m2xenix.uucp
wilker@gauss.math.purdue.edu (Clarence Wilkerson) (05/29/90)
About a year before Turbo Pascal hit the CP/M market, I did a complete dis-assembly of the p-code machine as distributed by Heath-Zenith for the H89 with hard sectored drives. The object was to produce a system that would run with hard drives and the newer soft sectored drives. The hardware interface was rather tangled in with the interpreter in this version. I ended up with a working standalone system for the newer hardware, and also a version that attached itself to a CP/M BIOS and was thus fairly portable to other CP/M machines. Randy Hyde's book was invaluable in doing the dis-assembly.
milne@ICS.UCI.EDU (Alastair Milne) (05/29/90)
>From: ef@karl.tools.uucp (Edgar Fuss) >Subject: Re: UCSD P-system >In-reply-to: randy@m2xenix.psg.com's message of 20 May 90 00:42:02 GMT > >This is the most interesting debate in comp.lang.pascal since months! >Anybody knowing details about III.x p-Code (the Microengine one's)? >Edgar More than I care to, but probably fewer than you'd want. It was the first p-machine whose details I learned -- for a compiler-writing class, as a matter of fact, where the teacher expected our compilers to generate executing programs. And I must say that emitting code for it was quite straightforward. We did no optimisation, of course, but then p-code is already pretty tight. There are some details of it that I can still remember, but you'd probably be better off first trying Western Digital, to see if they still have copies of their documentation available. I don't think that, at the time, the Internal Architecture Guide was yet a separate document. Rather, I think it was its own section in the MicroEngine manual. Of course, this was a number of years ago, so they may well have none available. Alastair Milne