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whit3rd whit3rd is offline
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Default Seeking Opinon on EPROM Problems

On Thursday, January 7, 2016 at 9:32:43 PM UTC-8, wrote:
I have a bunch of the same units now that I kinda work for factory service. These are Karaoke machines which are modified CD/DVD players.

I get like three different symptoms on certain models. OK there was a fourth that was even weirder but that was only one out of a bunch. Also, out of a bag of EPROMs they have the same symptoms. We got alot of parts that are used and that is something totally else to deal with.

Anyway, when you find there are only three major symptom sets that follow these EPROMs around (I spent the better part of a day switching them...


Well, if the EPROMs were really in a bag... that usually isn't proper storage.
Read and generate checksums for the EPROMs; if the checksum is wrong, different from
others with the same version label, that's a bad part.
I wouldn't waste time erasing/reburning old parts (are they UV EPROMs, or flash, or EEPROM?), I'd just
program a flash replacement. The parts are cheap enough, and 'the better part of a day' is not.

Of course, generate a checksum after burning, verify that before using the part.