[time-nuts] Maintaining boatanchors (was Capacitor Failures)

[Chuck Harris]

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.
>
>