1394A external device can't be recognized

techo

hi All,
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( s, s8 a: Q( |  vis there any one had experienced 1394A external device can't be recognized under OS?
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I encounter this kind of issue recently.

OS is Vista & XP.

1394A controller is Ricoh.

, W! d6 H9 R$ V8 M6 A9 qthe 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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. h' M' _' u+ Z. n6 C, Uindeed there are some differents but I don't know why.
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' @! l- u3 [) M. ^, HI wonder it's caused by BIOS but how to prove it?
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is there any spec or document could let me refer to?

) T" |4 Y% Y% D9 h' Y0 EThanks anyway!