2016-05-09 19:42 GMT+02:00 Eric Smith <[email protected]>: > On Mon, May 9, 2016 at 5:13 AM, Mattis Lind <[email protected]> wrote: > > Last time I had a PROM failure is what the internal address decoding that > > failed which was easily seen as certain patterns repeated all the time > > Not impossible, but it seems more likely that one of the address input > pad buffers failed. >
You're probably right in that. On the other hand looking back on what I wrote I see that I wasn't completely accurate in describing the symptom... The symptom was that the upper 128 words was inclusive-OR:ed with the lower 128 words resulting in a quite strange upper 128 words. That was my reason for suspecting the faulty address decoder. Anyhow I have now ordered a bunch of Texas TBP24SA010 chips which I hope the old Data I/O 29B will be able to program successfully.
