Programming Bipolar PROMs

Tom Hunter ccth6600 at
Mon Sep 27 10:23:02 CDT 2021

While restoring and repairing a Data General Nova 2/10 I found a bad
bipolar PROM on the CPU board. The PROM has open-collector outputs and is
organized as 32 words by 8 bits. It appears that one of the open-collector
driver transistors is faulty (but it could also be that a fuse has

The part is an Intersil IM5600CP, but these were also made by others, for
example Signetics and Philips made the 82S23 and TI and NTE made the faster
SN74S188N. Some vendors still sell these parts and there are even a few on

How do I program these PROMs? I found one somewhat obscure description of
the algorithm in the NTE datasheet, but I suspect that each manufacturer
had (somewhat) different algorithms.

Is there an affordable commercial programmer out there which can program
these PROMs?

Is there a simple design out there which I could breadboard for a one-off
programming job (maybe using an Arduino to control the programming

Thanks and best regards
Tom Hunter

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