25 May
1999
25 May
'99
5:04 a.m.
Roger Merchberger <zmerch(a)30below.com> wrote:
---snip---
You're right about the EPROMs not being deliberately erased... but one of
the *early* discussions on this list was about the data integrity or data
"life" of your average EPROMs... which is only 10-15 years or so.
Hi
As far as I know, EPROMs should last more than 10 years. This
was the value that Intel set as a minimum guaranteed hold time for
their 2716's, that I remember. It is always possible that any particular
EPROM doesn't hold even that long. The average hold time for
EPROMs is surely greater than 20 to 30 years.
I have some 1702A's that are still holding data after 26 years.
I've made copies and have a listing just in case though. I've
made hex listings of all the EPROM's in my equipment. I stick them
in the machine some place.
As for having the labels fall off, I was told by one of the
EPROM designers that even sun light would take several years
to erase EPROMs. Most indoor light has less than a thousandth
the short UV that sun light has. UV doesn't reflect from surfaces
vary well either so any indirect light would have even less
UV in it. Still I keep tape over the windows on my EPROMs.
One should note that even clear tape blocks most UV. Try it
for your self, try to erase a EPROM with clear tape on it!
It will take a lot longer.
Dwight