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wmhobbes
2006-01-26, 22:11
Connecting the 770 via the USB cable to both my PCs running Linux gives very poor performance in file trasfer (from the MMC).

The host machine reports USB being version 2.0, but only "full" (12Mbps) speed capable.

Is that normal (sounds weird to me)? Or something is wrong here?

putkowski
2006-01-26, 22:26
Connecting the 770 via the USB cable to both my PCs running Linux gives very poor performance in file trasfer (from the MMC).

The host machine reports USB being version 2.0, but only "full" (12Mbps) speed capable.

Is that normal (sounds weird to me)? Or something is wrong here?

MMC cards' speeds can vary widely. My Kingston card is noticeable faster than the "stock" 64MB card.

wmhobbes
2006-01-26, 22:40
MMC cards' speeds can vary widely. My Kingston card is noticeable faster than the "stock" 64MB card.

Absolutely agree, but it seems the speed is negotiated at 12Mbps with the host:


T: Bus=03 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#= 3 Spd=12 MxCh= 0
D: Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1
P: Vendor=0421 ProdID=0431 Rev= 3.08
S: Manufacturer=Nokia
S: Product=Nokia 770


See the Spd=12?
"high speed" devices show Spd=480 there:


T: Bus=04 Lev=02 Prnt=06 Port=00 Cnt=01 Dev#= 8 Spd=480 MxCh= 0
D: Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1
P: Vendor=0ea0 ProdID=2168 Rev= 2.00
S: Manufacturer=USB
S: Product=Flash Disk


weird...