1394A external device can't be recognized

techo

hi All,
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is there any one had experienced 1394A external device can't be recognized under OS?

I encounter this kind of issue recently.

, v( I" ~7 w, x+ |$ `3 fOS is Vista & XP.
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1394A controller is Ricoh.
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8 W2 L$ R1 h; P1 jthe situation is I could see the removable icon shown on the system tray but there is no device in OS device manager.
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indeed there are some differents but I don't know why.

I wonder it's caused by BIOS but how to prove it?

is there any spec or document could let me refer to?
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Thanks anyway!