Re: Comsol UHD-3542 3.5" HDD enclosure ( PATA to USB 2.0 )

[Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>]

On Thu, 3 May 2007, Jesus Jr M Salvo wrote:

> Hi,
> 
> Just adding another feedback, I tried kernel 2.6.20-1.2948.fc6 ....
> and it behaves the same as above. However, what I did not try earlier
> was to attach the USB enclosure to the USB port prior to startup /
> poweron of the laptop.
> 
> If I plugin the USB enclosure to the USB port of my laptop, then I get
> full-speed!! as shown by /proc/bus/usb/devices, like this:

You mean "high-speed".  Full speed would be reported as 12, not 480.

> T:  Bus=02 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#=  2 Spd=480 MxCh= 0
> D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
> P:  Vendor=048d ProdID=8903 Rev= 2.00
> S:  Manufacturer=ITE Tech. Inc.
> S:  Product=USB2IDE Bridge Controllee
> S:  SerialNumber=000000000065
> C:* #Ifs= 1 Cfg#= 1 Atr=c0 MxPwr=100mA
> I:  If#= 0 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=usb-storage
> E:  Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
> E:  Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
> 
> The speed says 480, and it does feel faster when doing a "find . -name
> '*' | xargs grep someword' on the directory mounted.
> 
> If i then unplug it from the USB port ... and plug it again a few
> seconds later, then I get back to high-speed only:

This is full speed.

> T:  Bus=01 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#=  4 Spd=12  MxCh= 0
> D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
> P:  Vendor=048d ProdID=8903 Rev= 2.00
> S:  Manufacturer=ITE Tech. Inc.
> S:  Product=USB2IDE Bridge Controllee
> S:  SerialNumber=000000000065
> C:* #Ifs= 1 Cfg#= 1 Atr=c0 MxPwr=100mA
> I:  If#= 0 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=usb-storage
> E:  Ad=81(I) Atr=02(Bulk) MxPS=  64 Ivl=0ms
> E:  Ad=02(O) Atr=02(Bulk) MxPS=  64 Ivl=0ms
> 
> 
> 
> ...and of course /var/log/messages will show that error about "not
> accepting address".
> 
> So now the question is:
> 
> *) Why does it work with full-speed if connected prior to startup, but
> works only with high-speed if connected after startup ??

It's quite possible that your BIOS is causing the problem.  Check the USB
settings in your BIOS configuration and see if changing them helps.

Alan Stern


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