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Computer System Associates CA 92121

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    Computer System Associates CA 92121

    Hi all,

    Well I recently purchased a stunning Motorola 68000 system made by Computer System Associates (CSA), 7562 Trade Street, San Diego, CA 92121.
    With a phone number back in the 1980's of (714) 566-3911

    It appears they are no longer in business. I have seen ads for them in some of the old 1980 period magazines.

    So felt it worth starting a section under Companies on them. Would like to find some history on the company, and maybe even contact information of engineer/s that designed this system.

    They must have made a few units as mine has a serial number A 001396. I have seen, mentioned on this site, one other very incomplete unit that was for sale on ebay a few years back.

    The workmanship and quality of the system I got, tells me they were Perfectionists, and I cannot believe someone, somewhere, does not have documents and hopefully Source Code for the onboard CSA Firmware.

    My unit uses a Motorola MC6800ECB (educational computer board) for the CPU/ Memory and a CSA purpose built Display and Keyboard PCB (68000 00106J, Serial number B1284) mounted above it. This is covered by a hinged 'Smoked" plastic cover that is white silk screen printed with functional identifers for the various readouts.

    This Display and Keyboard PCB has a 'Serial Display Interface" daughter board (00675 S/N 1439) that has an Intel C8751H-12, that is handling the interface between the 68000 and the 20 key keyboard, the 6 rows of 7 segment displays and 4 rows of 16 leds; that display the internal states of the 68K as it runs.

    CSA 68K system running.jpg

    I am looking for someone that has the source code for the Display Processor on the upper PCB. It is contained in an Intel C8751H-12 micro, with a label over the Eprom window reading "Display 992-00233-1". Have tried reading it on a few Programers and get different check sums on subsequent reads. Tried burning a blank Intel C8751H-12, but no joy as it just runs 'a random code', flashing all the leds and 7 segments. I assume the security bit was set in the original CSA C8751H micro, after it had been programmed.

    CSA also have a pair of eprom on the Main 68000 board labeled PETEBUG U10 992-00220 & U11.. 992-00221.

    It seems to get repeatable reads on these with check sums for U10 being AB45 and U11 ...7A63

    Will try and upload more photo shortly.

    Any help will be appreciated.

    David Broadbent
    Melbourne, Australia


    I was the founder of CSA and designed the Micro 68000. I just stumbled across your post. Amazing!

    Vic Wintriss
    San Diego, CA


      FIY April 2017

      I have now started to post info on this computer in the Forum/Genres/Other section here on

      Of course it would be good to add more info on CSA to this section.