TMS 2532 EPROM adapter: one byte every 50 ms…..

EPROM progammers seem like a thing of the past, still, they are very popular for test equipment repair, arcade games, and all kinds of other occasions where small amounts of data need to be stored in a bulky, fancy package.
Such programmers, mostly copies of the “Willem” design, are widely available, Made in China, and generally, these work pretty well. Well, as luck would have it, most of the ancient pieces of equipment use 2532 EPROMs, and just this kind is not supported by the common programmers, which support the 2732….. same capacity, different pin layout.

2732 pinout



To adapt the 2532/2532A (these only differ by their programming voltage, 25 V vs. 21 V – make sure the set it correctly) to the common 2732 programmers, the only thing you need is a small adapter, with a most complicated schematic (the only pins that change are 18, 20 and 21). Most of these EPROMs require programming pulse widths of about 50 ms, but often program OK with just 10 ms, or less.

2532 eprom adapter for programming schematic

2532 programming adapter view 2

2532 programming adapter view 1

2 thoughts on “TMS 2532 EPROM adapter: one byte every 50 ms…..”

  1. Hi sir!
    Very good article!
    I need to program TMS2532A eprom with Willem 4x programmer…unfortunately,this programmer support only 2532 and 2532A but only read….
    It’s possible program TMS2532A with this adapter and select 2732A option?Thanks!

    1. It should be possible, at least worth to try-there seem to be multiple versions of the willem programmers, so it is a matter of luck.

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