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Thread: Seals 32KS RAM board

  1. #1

    Default Seals 32KS RAM board

    I have a Seals 32KS, a 32K static RAM board. Searching for information or ads on this board has not yielded much. The 8KS SRAM board manual is available online, but I've only found scant references in the old journals to the 32KS, mostly in quarter page ads of mail-order retailers. I'm guessing that the board was a short run between the popular 8K board and the 64K SRAM card that was sold around the same time they came out with their PUP-1 system. The silkscreen copyright is 1978 and all of the TMS4044 4Kx1bit chips have date codes of 7810.

    Mine wasn't working originally, but I was able to get it running. I documented the repair here:

    https://sites.google.com/site/retrob...ai-8080-page-6

    And today, I finally had a little time to figure out how the DIP switch settings select the address range for the board. VICTORY!

    I would welcome learning about any information out there on Seals and this board in particular.

    IMG_8525.jpg

  2. Default

    Glad to hear of your conquest.
    Heh, sound to me like you are the resident expert on the Big Seal!

  3. #3
    Join Date
    Jan 2010
    Location
    Central VA
    Posts
    3,200

    Default

    I have a Seals 16K static board that looks like it was either based off of the MITS 16K static board, or maybe MITS purchased the design and used it for their 16K board -- it uses SEMI4200 4K x 1 RAMs, which are a 400 mil device instead of the 300 mil TMS4044. I think I have a hand-drawn jumper map that came with it, but like yours, no documentation, no mentions in any publications from the time.

    Have you found the TMS4044s to be reliable? I've had bunch of boards with them, and usually end up replacing a bunch per board. A lot of times, the legs rot off.

  4. #4

    Default

    Most of the TMS4044's had legs that were heavily oxidized, a number with serious leg rot as you've noted. I re-soldered at least three pins. Only one out of 64 was outright bad on this board, though. I've had many more 2102's fail "hard" (bad bits reading and writing from the front panel) and "soft"—throws errors when running CP/M, but reads / writes fine from the front panel.

    I'm not sure how I feel about being the 32KS resident expert. Resume builder?

    Curious: Do any Seals PUP-1 computers still exist?

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