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Thread: 384k memory card, but for what?

  1. #1

    Default 384k memory card, but for what?

    I recently came across an IBM Eduquest (seperate thread), and with it came a memory card of sorts. It was a blurry Craigslist-esque image, but it was a memory card of some description. I got the package today and realized it was not IBM. First thought was for the TI-99/4A, but I've come to the conclusion is likely isn't.

    It does have some markings on the PCB, but google comes up with nothing relevant. The big chip is a TMS 4500A, with a 8445 date code. The ram chips are all 64kbit, and thus total 384KB. I looked up the spec sheet of the 4500a and it seems to be pretty universal to any processor. 8086,Z80,68000,TMS9900,etc. The extension card is just that, has 30 contacts on each side. This connection is the same as the one in the ti-99/4a PEB box. But without voltage regulation on the memory card, it is highly likely it is going to catch fire if I put it in a PEB.




    The extension card is exactly that. Has a stylized "R" at the top with memory bus, "made in taiwan", "3000-0004" on the top, and "san hua tien co 94v0" on the rear.

    The main card is just as descriptive. it is labeled 3000-0003 rev. 2, and A2100-000. First thought was Amiga 2100. That was a quick dead-end.

    If anyone knows what this goes to. I'd love to know! Thanks!
    It is a mistake to think you can solve any major problems just with potatoes.

  2. #2
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    I was going to say some sort of PC clone as 384 was used to take 256k to 640k but not enough pins....
    Dave
    G4UGM

    Looking for Analog Computers, Drum Plotters, and Graphics Terminals

  3. #3
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    I am fairly sure those go to a Tekmar/Quadram Drive 2 expansion unit for a PCjr.
    PCjr, DTK PC-XT Turbo, 386DX 33, 486 laptop, Pentium 120, Pentium III 500, various old laptops, Commodore Colt, all working. I also have a 286 that I need to see if I can repair.

  4. #4
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    Correct. The memory board sits on the left side of the upper-deck case (when viewed from the front) and the bridge board connects it to a board that sits vertically in the double height side-car add-on.

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