[adsomers]

Hey there. Anyone know how to disable the i/o components of the logic board altogether?

I've got a 2 y.o. 15" Aluminum 1.25GHz G4 Powerbook. Some time last year, I noticed that my logic board was fried because I could not use either of my firewire ports. I have been using USB 2 for all serial i/o, but lately have been experiencing frequent kernel panics and occasional system lockups.

The panics most commonly occur on boot, PMU reset helps get the system up and running. All the entries in the panic.log look like this:

*********

Sun Nov 27 19:26:07 2005


Unresolved kernel trap(cpu 0): 0x300 - Data access DAR=0x0000000000000059 PC=0x00000000000A8EC0
Latest crash info for cpu 0:
Exception state (sv=0x3284F500)
PC=0x000A8EC0; MSR=0x00001030; DAR=0x00000059; DSISR=0x40000000; LR=0x000326E0; R1=0x1CAC3980; XCP=0x0000000C (0x300 - Data access)
Backtrace:
0x00034AFC 0x000326E0 0x00032BD8 0x00025220 0x000A7F50 0x000ABC80
kmod scan stopped due to missing kmod page: 00000000
Proceeding back via exception chain:
Exception state (sv=0x3284F500)
previously dumped as "Latest" state. skipping...
Exception state (sv=0x38392780)
PC=0x000ACF84; MSR=0x00009030; DAR=0x0115C000; DSISR=0x42000000; LR=0x0077C990; R1=0x1CAC3CB0; XCP=0x0000008C (Preemption)
Backtrace:
0x00000000 0x0077DB24 0x0077D3DC 0x002CF960 0x002CE828 0x000A9814
Kernel loadable modules in backtrace (with dependencies):
com.apple.driver.AppleFWOHCI(2.5.2)@0x777000
dependency: com.apple.iokit.IOPCIFamily(1.7)@0x458000
dependency: com.apple.iokit.IOFireWireFamily(2.0.8)@0x6e9000
kmod scan stopped due to missing kmod page: 00000000
Exception state (sv=0x324B9780)
PC=0x00000000; MSR=0x0000D030; DAR=0x00000000; DSISR=0x00000000; LR=0x00000000; R1=0x00000000; XCP=0x00000000 (Unknown)

Kernel version:
Darwin Kernel Version 8.3.0: Mon Oct 3 20:04:04 PDT 2005; root:xnu-792.6.22.obj~2/RELEASE_PPC
panic(cpu 0 caller 0xFFFF0003): 0x300 - Data access
Latest stack backtrace for cpu 0:
Backtrace:
0x00095698 0x00095BB0 0x0002683C 0x000A8304 0x000ABC80
kmod scan stopped due to missing kmod page: 00000000
Proceeding back via exception chain:
Exception state (sv=0x3284F500)
PC=0x000A8EC0; MSR=0x00001030; DAR=0x00000059; DSISR=0x40000000; LR=0x000326E0; R1=0x1CAC3980; XCP=0x0000000C (0x300 - Data access)
Backtrace:
0x00034AFC 0x000326E0 0x00032BD8 0x00025220 0x000A7F50 0x000ABC80
kmod scan stopped due to missing kmod page: 00000000
Exception state (sv=0x38392780)
PC=0x000ACF84; MSR=0x00009030; DAR=0x0115C000; DSISR=0x42000000; LR=0x0077C990; R1=0x1CAC3CB0; XCP=0x0000008C (Preemption)
Backtrace:
0x00000000 0x0077DB24 0x0077D3DC 0x002CF960 0x002CE828 0x000A9814
Kernel loadable modules in backtrace (with dependencies):
com.apple.dp
*********

I'm guessing that if I disable the FW component of the Logic Board, I might see a useful/informative change. Anyone got anything to say?

FYI: reformatting, resetting pram/nvram, PMU reset, memory swap will not fix this.

Thanks in advance,
Adam Somers
http://oneofmillions.com

[mduell]

The thread title made me think of this guy. I'm sure he could come up with something to disable your Firewire ports.

[adsomers]

Yeah, I bet that would be a step in the right direction. Now that you mention it, my hypothesis to explain this (all to common) anomaly is the 48v my audio device was drawing from the FW port for phantom power of 2 microphones over 4 sustained periods of 1 hour each. I'll bet that if I hook the phantom power line of an XLR cable to the power out of the FW port for 4 hours It'll be back up and running in no-time. It just wants me to give back the power I stole from it. Who wouldn't?

Adam Somers
http://music.calarts.edu/~asomers

[analogika]

[Evinyatar]

You could try deleting the FireWire related kexts from /System/Library/Extensions

[adsomers]

Originally Posted by analogika

Do you have a moog source and a casio VL Tone in your setup???

[analogika]

um, yeah - why?