Hi The issue with the mask parts is the same as pretty much all IC's. The packages aren't quite hermetic / the passivation isn't quite perfect / the top metal goes away over time.
Bob On Oct 23, 2010, at 9:01 AM, Chuck Harris wrote: > Hi Magnus, > > I keep an old Toshiba 1963 486 based laptop in good working condition > to allow me to run my old ADVIN U84 DOS based programmer. I check it > out from time-to-time. > > I can't do much about the mask rom'd parts, though I don't think they > have any higher of a failure rate than any other IC. The eprom based > controllers, can be a worry, but I can program most of them from the > 1980's on... assuming they aren't protected. > > There are a myriad of open source format converters available... things > that convert S to intel hex, etc... I seem to recall even writing some > of them...but that is a foggy memory by now. > > I find my violins' EPROMS are very stable, and last centuries. > > -Chuck Harris > > > Magnus Danielson wrote: >> On 10/23/2010 01:02 AM, Chuck Harris wrote: >>> I don't believe the parts are failing due to structural >>> problems, but rather are just leaking down their buried charge. >>> >>> It should be quite possible to refresh them by erasing them and >>> reprogramming. >> >> If you maintain EPROM programmers for them in workable shape. With this >> I mean you need to ensure the complete path, not only the programmer >> hardware but also any supporting software and interfaces such that you >> can upload/download images, convert formats etc. etc. >> >> Most of the 27xx EPROMs are not my main worries, but older and stranger >> stuff. If a ROMed controller fails, what happends then? The 5334 has no >> less than three microprocessors with EPROMs... where do I get a spare of >> those? >> >> Backup of EPROMs is a concern to take serious. I have been sloppy on my >> side. It is not only for the measurement instruments, I have the same >> issue with my musical instruments too. >> >> > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
