[Coco] MPROM woes (cured)
operator at coco3.com
Sun Nov 16 10:29:19 EST 2008
At 09:08 PM 11/15/2008, you wrote:
> > I tried 4 9v batteries a few days ago and for some reason it wouldn't
> > work. That is, the software kept reporting a no-go on the first
> > write cycle. The EPROMs remained blank. Maybe it was just some of
> > the batteries in series holding up the rest, as I didn't check the
> > total voltage.
>There remains the possibility that those 4-battery EPROMs you tried are now
>fried, and are not only blank but now unprogrammable.
I'd be willing to bet that the little regulator IC would cook instead
of the wrong voltage getting through it.
The EPROM I was trying to program (and failed) is a 68X6048 which I
thought was the same as a 2764 but turns out to be a 27512 (64k x
8k). It appeared to read well but not program.
I've got 25 of the 27512's and unless I can pin-wire them to act like
a 27256 or below, they're useless in my CoCo projects.
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