firewire screwup

Timothy A. Seufert tas at
Thu Aug 30 06:48:51 EST 2001

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:
>>  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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