22 Jan
2017
22 Jan
'17
10:57 a.m.
I don't know about most people but this solution has been around for
decades.
I locate the battery on the failed part with a small magnet, then grind the
epoxy down to it then pick it out with a sharp pointed tool. Once I expose
the connection point I older two wires then epoxy a small coin-cell holder
in that spot and it s done. I've done this more times than I care to count
and its effective and the replacement battery some over 10 years old
now have not failed. But just in case I have a bag of NOS replacements
(and pulls from socketed boards) all with dead batteries from age. There
is no magic to this.
Allison
On 01/22/2017 01:20 PM, Ali wrote:
Jon,
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.
Jon