GRID 2MB SRAM CARDS

Robert Williams (rwill@seminole.saccw.cc.ar.us)
Tue, 13 Aug 1996 21:35:56 -0500 (CDT)

Well, I hate to rain on anyone's parade, but I have had a bunch of
trouble with Grid SRAM cards in the past...I've also figured out how to
overcome the trouble... and so I will tell my tale to the mailing list in
the hopes that it will be helpful.

I purchased a 2MB Grid SRAM card from Surplus Technology about a year
ago. Initially, it worked just fine... then it started to give weird read
and write errors.... so, since it was only about a month old, I was able
to exchange it for a new one.

the "new" card worked fine for almost a year.... when I got my OGO, the
OGO would not recognize the formatting, so I reformatted it and then it
would work on the OGO until I turned the OGO off and the next time I
turned it on... it would ask me again if I wanted to format the card...

Well I wracked my brains trying to figure out a way to get this card to
work. I carrled back Surplus Tech and they wouldn't exchange it. I tried
formatting the card on a 200LX... I checked the battery voltage on the
card, I tried pulling the battery for 24 Hours.... basically, I exhausted
all possibilities. THe card would format in the 200LX: but marked 1.9 MB
of the card as "bad sectors". FInally, I decided, with nothing to lose,
to tear the card apart and see if there might be a loose connection or
something that could be fixed... I figured that it beat throwing my
$80.00 card into the trash.

Once the metal covers were carefully peeled off of the card frame the
problem became obvious: there is a tiny little Lithium battery soldered
in internally. a quick check revealed that this battery was dead (2.1
volts) and so I broke out my reading glasses and my soldering iron and
unsoldered the tiny battery leads. After this, I went ahead and tested
the card in the slot.... and it WORKED! No more formatting errors. I
replaced the metal coveres with super glue. And the card has worked just
fine every since. I didn't bother to try replacing the solder-tabbed
internal lithium cell. I figured that If the regular backup battery gets
low, I can just replace it while it is in the slot anfd the OG is powered
on. The card now works and is formattable in the 200LX and the OG and
even in my 100LX.

So, now it becomes clear why the SRAM cards are available for so cheap...
mainly because the cards all have internal backup batteries that are on
their last leg... and Grid (or whoever) decided to dump them quick before
they become unusable without major surgery. There you have it. The rest
of the story.

Robert S. Williams, MD
rwill@seminole.saccw.cc.ar.us