Re: Z-RAM ultra 2... replacing the battery?

["John Van Winkle" <appleiieman@charter.net>]

I would suggest changing the batteries first.  The batteries I used were the
1.2V AA rechargables from radio shack.  I would suggest using the 1.7V AA
that radio shack has and a battery holder that you can wire to the board.
Email me and  I will send you a pic of what I did.


John Van Winkle


"Gary" <dontyouspamme_vengefultacos@comcast.nospam.net> wrote in message
news:X0RWc.227473$eM2.144836@attbi_s51...
>
>  Wayne Stewart wrote:
> >
> >>I'd think that if it wouldn't work after a few hours, more time isn't
> >>likely to help. Having a rechargable battery, you'd think that the
> >>charging circuit would power the clock even with a dead battery. If
> >>you can, it'd be nice to check the voltage at the battery leads when
> >>the IIc is running in case it's the charging circuit that's not
> >>working
>
> Checking the leads on the battery would be problematic when running, since
> the card sits face up in the //c, and has to be socked down, since it
> connects into the MMU and CPU sockets on the motherboard.
>
>  Michael J. Mahon wrote:
>
> > That's right.  The circuit operates from the battery _only_ when
> > the computer power is off.
> >
> > That means that the software is choking because the clock
> > currently contains an invalid date/time.  Try running the clock
> > setting software and see if that fixes it for a warm boot (since
> > the battery is still not known to be working).
>
> I had booted up the clock setting disk before, and the setting software
> crashed into the monitor, too. Just now, I realized that there was the off
> chance that the setup disk would actually run the clock driver before it
> ran the setup program... (which, it turns out, it does... sorta stupid
> design there) so I booted up from another disk, then ran the clock setting
> software directly. And it worked! The clock had a date somewhere in the
> year 52. I reset it to the current date and time, then did a warm boot.
>
> The clock reading software was able to run without crashing, but it read
> back the exact date and time I had set with the clock setting program.
> After about 20 minutes, rebooting into any of the disks that has the clock
> driver still resulted in the exact time I had set being read. So it looks
> like the clock accepted the data, but won't actually update it.
>
> Next I tried a quick powercycle to see what would happen. Loading the
clock
> driver results in the crash to the monitor again. Running the clock setup
> software also ends up in a crash to the monitor, with the time on the
> screen showing a date in 04, but a different month and random time. Just
> before the crash, the time flips around madly, as if the software is
> reading from a spinning clock.
>
> So... I'd guess I'm looking at both a dead battery and a screwy clock
chip?
> A bit of googling turned up a PDF version of the Z-RAM's manual
> (http://tinyurl.com/6xn6l), which identifies the clock chip as an OKI
> 6242B. The spec sheet I found:
>
> http://www.okisemi.com/jp/datadocs/doc-eng/msm6242b.pdf
>
> says it has an onboard crystal... so I wouldn't be anle to swap out a
> crystal to see if that's the culprit. I'm not able to discern many other
> relevant details from the sheet (it's been almost 20 years since I flunked
> my last EE class ;-). The datasheet is dated 2002, so I assume the part is
> still made... perhaps I could just buy another one and swap out the
> existing chip (I think everything on the board was socketed, so I wouldn't
> have to tax my limited soldering skills).
>
> Thanks for all the help and suggestions so far!
>
> Gary
>
>
>
>