Re: firewire screwup

On Wed, Aug 29, 2001 at 04:38:51AM -0700, Timothy A. Seufert wrote:

It isn't enough to remove the main battery of a PowerBook -- all Macs
and PowerBooks have a tiny internal backup battery which keeps the
real time clock and NVRAM contents alive when the normal power
sources are not present.  You have to disconnect it if you want to
reset anything.  You also need to allow time for all capacitors to
fully discharge before the NVRAM is truly cleared (it's battery
backed SRAM, and SRAM can keep its contents alive on microamps of
current).  Overnight usually seems to be enough.

that won't even work on a NewWorld, since on newworld nvram contents
are stored in flash.

It's probably worthwhile to try removing the backup battery -- I can
tell you that I resurrected a Blue&White G3 that would not respond to
anything else.   (I had put a value into an OF variable that caused
the system to crash before OF could even respond to Cmd-Opt-P-R.)

i did something like that once as well, removing the battery did me no
good whatsoever.  only entering the backup OpenFirmware image worked
and allowed me to reset the nvram.

--
Ethan Benson
http://www.alaska.net/~erbenson/

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Ethan Benson writes:
 >
 > i did something like that once as well, removing the battery did me no
 > good whatsoever.  only entering the backup OpenFirmware image worked
 > and allowed me to reset the nvram.
 >

So, how do I do that?

Marcus

--
---------------------------------------------------------------------
Dr. Marcus Metzler
mocm@netcologne.de                     http://www.metzlerbros.de
mocm@convergence.de                    http://www.convergence.de

Convergence Integrated Media GmbH
Rosenthaler Str. 51
D-10178 Berlin
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At 4:16 AM -0800 8/29/01, Ethan Benson wrote:

On Wed, Aug 29, 2001 at 04:38:51AM -0700, Timothy A. Seufert wrote:

quoted

 It isn't enough to remove the main battery of a PowerBook -- all Macs
 and PowerBooks have a tiny internal backup battery which keeps the
 real time clock and NVRAM contents alive when the normal power
 sources are not present.  You have to disconnect it if you want to
 reset anything.  You also need to allow time for all capacitors to
 fully discharge before the NVRAM is truly cleared (it's battery
 backed SRAM, and SRAM can keep its contents alive on microamps of
 current).  Overnight usually seems to be enough.

that won't even work on a NewWorld, since on newworld nvram contents
are stored in flash.

Did work on a New World for me (B&W).  Maybe only core99 & later use
flash for nvram?

I'll have to ask a guy I know at Apple about this.  He works with
prototype hardware&firmware that have lots of bugs, so the various
reset procedures are permanently burned into his brain.
--
Tim Seufert

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My friend at Apple says to press and hold the reset button on the
back of the powerbook (behind the I/O door) for at least 60 seconds.
--
Tim Seufert

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Timothy A. Seufert writes:
 >
 > My friend at Apple says to press and hold the reset button on the
 > back of the powerbook (behind the I/O door) for at least 60 seconds.
 > --
 > Tim Seufert
 >
 >
Nope, didn't work. Still SelfID Timeout in open firmware and no MacOs
boot. Well at least linux still works.
Is there a way to disable firewire, so that the MacOses won't probe
for it and hang?

Marcus

--
---------------------------------------------------------------------
Dr. Marcus Metzler
mocm@netcologne.de                     http://www.metzlerbros.de
mocm@convergence.de                    http://www.convergence.de

Convergence Integrated Media GmbH
Rosenthaler Str. 51
D-10178 Berlin
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At 10:48 AM +0200 8/30/01, Marcus O.C. Metzler wrote:

Timothy A. Seufert writes:
 >
 > My friend at Apple says to press and hold the reset button on the
 > back of the powerbook (behind the I/O door) for at least 60 seconds.
 >
Nope, didn't work. Still SelfID Timeout in open firmware and no MacOs
boot. Well at least linux still works.
Is there a way to disable firewire, so that the MacOses won't probe
for it and hang?

Possibly -- you could remove the firewire controller's node from the
OF device tree before booting MacOS, and then MacOS would be unlikely
to even know of its existence.  But I'm not nearly enough of an OF
hacker to know whether that's really possible, or how to do it.

I guess at this point damage must be considered likely.  Have you
tried using the Hardware Test CD that came with the computer?
--
Tim Seufert

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Timothy A. Seufert writes:
 >
 > Possibly -- you could remove the firewire controller's node from the
 > OF device tree before booting MacOS, and then MacOS would be unlikely
 > to even know of its existence.  But I'm not nearly enough of an OF
 > hacker to know whether that's really possible, or how to do it.
 >
 > I guess at this point damage must be considered likely.  Have you
 > tried using the Hardware Test CD that came with the computer?

That was one of the first things I did. The test claims everything is
fine.

Marcus

--
---------------------------------------------------------------------
Dr. Marcus Metzler
mocm@netcologne.de                     http://www.metzlerbros.de
mocm@convergence.de                    http://www.convergence.de

Convergence Integrated Media GmbH
Rosenthaler Str. 51
D-10178 Berlin
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