SC84 computer

Collection of information and attempts to recreate the firmware

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Someone asked if anyone had the firmware for this. I collected the articles and some newsletters. The MCOS firmware was in a newsletter, so I OCR'd it and recreated a source code file. Some OCR errors may be in there, but it is a good start to seeing what it does.
Then Wim Verstrepen joined the project and provided images of the firmware, software, and top-quality images of his boards.
I have disassembled the OS and the font ROM data.



WordStar Overlay v3.00 1980 Micropro International - patched for SC84/SCIDOS (super-fast VDU access)

octet-stream - 33.50 kB - 04/06/2021 at 21:28



WordStar MSGS-Overlay v3.00 1980 Micropro International - patched for SC84/SCIDOS (super-fast VDU access)

octet-stream - 24.00 kB - 04/06/2021 at 21:28



WordStar v3.00 1980 Micropro International - patched for SC84/SCIDOS (super-fast VDU access)

octet-stream - 15.75 kB - 04/06/2021 at 21:28



BASIC-80 CP/M v 5.2 14-Jul-80 - Microsoft

octet-stream - 23.88 kB - 04/06/2021 at 21:26



Expanded Disc Basic v 1.0d - SCITEX

octet-stream - 17.50 kB - 04/06/2021 at 21:24


View all 45 files

  • 1 × MK38801 Mostek Serial, Timer and Interrupt controller chip.

  • Project Journal

    Keith03/20/2021 at 15:29 0 comments


    Started project.


    Wim Verstrepen joins the project. He has a working machine.


    Wim uploaded binary images of the CPU and VDU ROM. Hex dump of the CPU ROM exposed a couple of errors in my newsletter OCR (E with bottom missing wrongly guessed be F, and an 8 was misread as a B). The code starts to differ significantly after about $0x065B, so I assume they are two different versions. Thus I cannot verify the rest of the newsletter version. The good news is that a known-good working version has been captured for posterity. Three cheers and beers to Wim!


    Wim uploaded some excellent high-res photos of the board set. These now replace the low-quality magazine scan pictures.

    I need to find out how to have more then six pictures in the gallery. Other people have more, so it is possible.

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mister35mm wrote 03/19/2021 at 23:02 point

I have a pile of documentation from the original Powertran PSI-COMP80 computer, and the user club newsletters, and some software on a small number of cassettes.

  Are you sure? yes | no

Keith wrote 03/20/2021 at 21:55 point

Thanks for the tip.  I'd scan the lot as a service to fellow techno-historians but the postage alone is about what I would pay out of my own pocket. You could try my local computer museum but museums have had no cash coming in for about a year. Likewise most people.

  Are you sure? yes | no

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