Unknown firewire device

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Level 1

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Unknown firewire device

Hello,

I've had some recent freezes (usually during logout from one account to another or shutting down). After a hard reboot, startup is long and external drives will not mount at times. After, switching cables and ports for the external drives (2 firewire, 1 usb (timemachine) it seemed to alleviate the problem but not entirely. After checking system profiler, my firewire bus lists my 2 external drives plus this:

Unknown Device:

Manufacturer: Unknown
Model: Unknown
Maximum Speed: Up to 400 Mb/sec
Connection Speed: Unknown

After ejecting the existing firewire drives, profiler still says this 'unkown device' is on the firewire bus.

Could this be related to recent freezes and drives not mounting properly?

Any thoughts would be appreciated -- thanks much.

Quad g5
6GB RAM

quad g5, Mac OS X (10.5.2)

Posted on Mar 9, 2008 7:48 PM

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Answer 1

Mar 10, 2008 2:49 AM in response to mousepotato

Hi basedes-

Does the monitor have a firewire hub?

Luck-

-DaddyPaycheck

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Answer 2

maclover

Level 4

3,850 points

Mar 10, 2008 3:03 AM in response to mousepotato

Hi. Seem to remember some discussion a while back about it being a good idea to disconnect any FW400 devices and reset the FireWire bus before any heavy FW800 work, such as cloning - because the combined FW800/400 bus on the G5 can get stuck at the 400 speed...

Anyway, after the hard Shutdowns, you could try running Disk Utility > Verify Disk to check for directory problems - if any are found you can use the 10.5 retail disk in this process

http://docs.info.apple.com/article.html?path=DiskUtility/10.5/en/duh1018.html

and reset the FireWire (last bit on the page here)

http://docs.info.apple.com/article.html?artnum=88338

Good Luck.

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Answer 3

japamac

Level 7

24,400 points

Mar 10, 2008 3:20 AM in response to mousepotato

Hi-

The report is exactly what is reported for the Apple Cinema Display firewire hub. By chance, do you have an Apple Cinema Display?

It has always amazed/astounded me that an Apple monitor on an Apple machine will report as "Unknown". I mean, really..........

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Answer 4

Mar 10, 2008 3:35 AM in response to mousepotato

Hi basedes-

Another brain cell just activated.

There is an internal chip that repeats the firewire signal for use on the front port. It reports as an "unknown" device, and with everything unplugged it will still show up.

This drawing may be of interest: Architecture

Luck-

-DaddyPaycheck

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Answer 5

mousepotato Author

Level 1

0 points

Mar 10, 2008 7:00 AM in response to mousepotato

Hi all and thank you for your replies,

I've got a Dell 2005fpw (usb hub). Yes, I've tried the reset firewire bus as well as disk utility first aid (permissions and retail disc). Sounds like the unknown device could be unrelated to the freezes... I did recently find out my Quad is among the serial # range for the power supply replacement program...though none of the described symptoms have occurred (knock on wood).

You guys rule:)

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