On Sun, 4 Apr 1999, Chuck McManis wrote: So, an assembly language program for them would look like lisp, as opposed to MOVs, ADDs, and so forth? And same with Pascal? But why would anyone want something that was microcoded to run Pascal? Are there any other languages that have gotten microcoded into a processor? --Max Eskin (max82(a)surfree.com)

Re: At about the same time as UCSD Pascal was being developed, Bill Gord of the UCSD Computer Center invented a LISP P-Code as the target "machine" for the BBN LISP (later INTERLISP) compiler that we were working on for the Burroughs B6700. Since Bill and I officially worked for Dr Ken Bowles (head of UCSD Pascal), I assume that Bill and Ken talked about the two "P-systems"...but I don't know which came first. I still have the source for our LISP -> pcode compiler, somewhere. BTW, one of the motivations for P-Code (for Pascal *and* LISP) was security / data integrity. Jim Madden (of UCSD Computer Center) had ported Wirth's Pascal to the Burroughs B6500 / B6700 only to realize that the lack of compiler-enforced security checks on the tagless variant record concept meant that programmers could generate their own values for pointers ... which would allow them to defeat the largely compiler- based security on the B6700. The B6500 line had no real hardware security (e.g., ring levels, page-level protection, etc ... it was nearly 100% software-enforced secuirty. ALGOL's pointers were restricted to point only within an array...which had hardware bounds checking. FORTRAN and COBOL didn't have pointers, and (with hardware bounds checking) had no method of generating random data addresses ... this meant that security on the B6700 was reasonably good. Unless you could generate your own code somehow :) (Normally, modifying existing program files would cause them to be marked as non-executable) Anyway, the P-Code implementation provided a means of implementing a language *and* having 100% control of the data accessed by the programs written in that language. This was probably one factor, in addition to the obvious portability aspects, that influenced the P-Code project. SS

A non-text attachment was scrubbed... Name: not available Type: text Size: 327 bytes Desc: not available Url : http://www.classiccmp.org/pipermail/cctalk/attachments/19990404/26c98825/at…

A non-text attachment was scrubbed... Name: not available Type: text Size: 711 bytes Desc: not available Url : http://www.classiccmp.org/pipermail/cctalk/attachments/19990405/02bb0fda/at…

At 11:47 04/04/99 -0400, Max Eskin wrote: Us Pascal freaks, that's who :-) The Pascal Microengine was a hardware implementation of P-code a stack based instruction set that was designed to make compilation from Pascal into it easy. The original compiler (P4) was written by Urs Amman (sp?) at ETH. I believe that this compiler formed the basis of the UCSD Pascal environment which was Java '70s style :-) One of the more seminal articles I remember reading in Byte was by Carl Helmers discussing how he'd just spent $5K on an Apple II to run UCSD Pascal. It was then I realized that micros would one day do the same amount of work that "real" computers did. One of my (non-existent) spare time projects is to get the Apple II in the cupboard up and running UCSD Pascal. All I need is the Language Card and the software (I think). Talking about Pascal compilers I seem to recall a multi (10?) pass Pascal compiler for (probably) RT-11. Anyone else recall this? Huw Davies | e-mail: Huw.Davies(a)latrobe.edu.au Information Technology Services | Phone: +61 3 9479 1550 Fax: +61 3 9479 1999 La Trobe University | "If God had wanted soccer played in the Melbourne Australia 3083 | air, the sky would be painted green"

On Mon, 5 Apr 1999, Huw Davies wrote: Just to stickle, it should really be the other way around: Java is UCSD Pascal 90's style. That's it. Really, any Apple ][ (Apple ][, Apple ][+, Apple //e, Apple //c, Apple //c+, Apple //gs) with at least 64K will run UCSD (Apple) Pascal. I've got the OS if you ever get around to wanting it. Sellam Alternate e-mail: dastar(a)siconic.com ------------------------------------------------------------------------------ Don't rub the lamp if you don't want the genie to come out. Coming in 1999: Vintage Computer Festival 3.0 See http://www.vintage.org/vcf for details! [Last web site update: 04/03/99]

Of course, I located the source to pdp8 Pascal some years ago, which is modified P4 (Urs Ammann, Kesav Nori, Christain Jacobi). I gave it to someone to put on a pdp8 ftp site, and of course I still have the code. -Lawrence (and you thought I only did Teraks) LeMay

A non-text attachment was scrubbed... Name: not available Type: text Size: 919 bytes Desc: not available Url : http://www.classiccmp.org/pipermail/cctalk/attachments/19990404/be4f3af1/at…