Petsoft 6502 FORTH

Welcome back to our Commodore Discussion forum. If you have a question, comment, problem, or just want to chat about Commodore, post it here for free.

Have some fun and talk to others interested in the Old and New Commodore world.

Moderators: wiskow, Trazan

Post Reply
lcww1
Posts: 2
Joined: Fri Apr 10, 2020 9:39 am
Are you a real person?: No... I am a spambot, delete my account!

Petsoft 6502 FORTH

Post by lcww1 »

Hello!

I've obtained a copy of Petsoft 6502 FORTH on cassette tape. I've attached a .tap image of the program made using a Tapuino. This tape image loads on a real PET 2001, and on the VICE xpet emulator.

Unfortunately, my tape came with no documentation, and I can't find any documentation relating to this program on the web.

From my research, I believe that this version of 6502 FORTH for the PET was developed by Programma International. See the article on page 40 of the August 1979 issue of Practical Computing (https://www.americanradiohistory.com/UK ... -S-OCR.pdf) - Petsoft founder Julian Allason describes a visit to Programma in California where he's shown a demonstration of 6502 FORTH and does a deal to market the program in the UK under his Petsoft brand. I can see that Programma International marketed a version of FORTH for both Apple II and PET from the advert on the final page of MICRO magazine from March 1979 (http://archive.6502.org/publications/mi ... r_1979.pdf).

I'm still hunting for documentation for the Programma 6502 FORTH. I'm thinking that the Apple II and PET versions must have been pretty similar, and there may be more chance of finding documentation for the Apple II version.

Anyhow, I hope this is of some interest. I'll be very interested to know if anyone can make anything of the attached .tap file on their PET!
Attachments
PETFORTH-VI.2.tap.zip
(119.68 KiB) Downloaded 197 times
lcww1
Posts: 2
Joined: Fri Apr 10, 2020 9:39 am
Are you a real person?: No... I am a spambot, delete my account!

Re: Petsoft 6502 FORTH

Post by lcww1 »

To aid in the analysis of the PETFORTH-VI.2.tap file, I've converted this to a .prg file using WAV-PRG (http://wav-prg.sourceforge.net) and I've attached the resulting file below:
PETFORTH-VI.2.prg.zip
.prg
(5.92 KiB) Downloaded 194 times
Looking at this .prg file in a Hex editor, shows that this really is the Programma International Inc PET Forth version 1.2, copyright 1978 - see the text located at x0CF0 onwards. The .prg header shows that the program will be loaded into PET RAM at x0400 onwards, and using the PET BASIC 2 monitor, I have verified that this is indeed the case.

However, I can't see an obvious entry point into the program - various guesses based on my reading of the code in the Hex editor have resulted only in crashes or being dumped into the monitor.

Any suggestions gratefully received - I think that someone more knowledgeable than me will be able to figure this out from the .prg hex....
User avatar
LoneWolf33
Posts: 67
Joined: Tue May 14, 2013 9:42 am
Are you a real person?: No... I am a spambot, delete my account!
Location: Budapest, Hungary

Re: Petsoft 6502 FORTH

Post by LoneWolf33 »

Hello,

I think there's a sample program merged into this prg file during the conversion, which may explains why it doesn't run.
If you check the very beginning of the file with a hex editor you'll see an explanation about the working principles
of the four stroke piston engine. This doesn't seem right.
HexView.jpg
HexView.jpg (170.25 KiB) Viewed 3127 times
Post Reply