VOGONS


First post, by Jed118

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Rank Oldbie
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Oldbie

Hello all,

I've recently obtained an NEC 9012 and the RTC was dead (socketed at least...) so I modded one with a battery and installed it. Didn't work. I eventually pulled a GW-12887-1 out of a 386 that needs a lot more work, and put it in. I was able to boot after the setup info was put in (Phoenix BIOS) but it just WON'T remember the details. I put the same GW-12887-1 into a DEC (also a very similar BIOS, Phoenix as well) and it works and keeps that computer's data.

Yes, the battery has 2.9v in it... Any ideas as to why the NEC specifically isn't holding any of the CMOS data?

Thanks,

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Reply 1 of 1, by jakethompson1

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Rank l33t
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l33t

On the DS12887A, pin 21 is intended to be connected to a CMOS clear jumper. The jumper grounds that pin.
The non-A versions have that unconnected.
If your board doesn't have a CMOS clear jumper, and grounds pin 22, it could exhibit these symptoms.