DS12887 pcb substitute with battery

Ali cctalk at ibm51xx.net
Sun Jan 22 12:20:50 CST 2017

Then why not use a dip compatible version of the DS chip? I mean yes this allows for switchable battery which is very nice but SMT soldering is not for everyone.

I wonder if there is a way to determine if there will be BIOS issues by switching the DS12887?

-------- Original message --------
From: Jon Elson <elson at pico-systems.com> 
Date: 1/22/17  9:16 AM  (GMT-08:00) 
To: General at classiccmp.org, "Discussion at classiccmp.org:On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> 
Subject: Re: DS12887 pcb substitute with battery 

On 01/22/2017 10:07 AM, Ali wrote:
> Al,
> I thought the problem with switching these chips was that part of the ROM code was embedded in them? I.e. it isn't just an issue of battery? Am I wrong? If I am then why not use one of the replacement chips that are available?
These don't have a lot of memory on them.  many early PCs 
stored some config info there, but generally the BIOS can 
reconstruct it if it isn't there.  I suppose there is a 
possibility that random data in the CMOS memory could cause 
the BIOS to try to use unavailable features and hang.  I 
don't think anybody put actual executable code in there.


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