How can I recover a bum battery?

Mikus Grinbergs mikus at
Sun May 23 14:37:07 EDT 2010

> The first series of things see-bstate does after battery insertion
> would be useful.
>  [on 1.5]
> remove the battery.
> ok see-bstate
> insert battery.  Then copy the 1st 5 or 6 lines after the 0 1 2 's
> stop repeating.

I booted the 1.5 on AC (without the battery).  Entered 'see-bstate' at
the ok prompt - saw string of '0 3' repeating.  Inserted bum battery.
The Battery_LED on the 1.5 soon changed to yellow.  Took the battery out
of the 1.5 and put it into the "testing" XO-1.  Battery_LED still yellow
when AC power plugged in.  Eventually, Battery_LED turned green.  I'm
concluding this problem battery is now o.k., too.  Thanks.

Unfortunately, I did not get a chance to copy the output lines (from
'see-bstate') when I inserted the battery - the battery is on one side
of the XO-1.5, and by the time I had turned the 1.5 over and located the
<ctrl> and <C> keys to stop the output, the first lines (upon insertion
of the battery) had already scrolled off the screen.  Because I noticed
that the Battery_LED was no longer dark, I did not repeat trying to
capture those "first things 'see-bstate' did after battery insertion".

My guess is that the better "support" in the XO-1.5, plus the procedure
of inserting the battery *while* 'see-bstate' was running, was enough to
"kick-start" the shadow ram in the battery (which had previously been
"reset" by running 'bat-rewrite-life' on the XO-1).


> Update the 1.5 with the latest firmware and then put the battery in
> that machine.  If the 1.5 does not do anything then I'll want to see
> what the state machines are doing.

I've got q3a39b in my XO-1.5.  If I remember correctly, just putting the
bum battery into the 1.5, then plugging in the AC, did not cause the
Battery_LED to light up.

> I have bat-debug-log that will log what the state machines
> are doing to a log file on SD or USB.  Do you have a serial port?

Yes, the 1.5 OFW does have 'bat-debug-log'.  Does that command take the
name of its output file as a parameter?  I did not get around to running
that command.

I do have a serial port (and have used it) - but at the moment, none of
my machines has its back off.


Thanks for helping me recover my bum batteries.  I did not know that
'bat-rewrite-life' (and 'bat-debug-log') existed.  How to use them (and
other useful commands) is the kind of information that would be helpful
to distribute to places where XOs get repaired.  [I looked at the DS2756
data sheet - it's NOT a "how to get a battery working again" guide!]

Thanks again,  mikus

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