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Re: usb info



Mark Knecht wrote:
On 7/13/05, Chuck Lawrence <CELawrence lbl gov> wrote:


1. how can I determine, with some certainty, whether the bus is 1.1 or 2.0?


cat /proc/bus/usb/devices and look at the "Ver=" entry. From my Gentoo
laptop. Note: The driver is also a good clue, I think. ehci is 2.0.
ohci is 1.1.

Yes, but the dead giveaway is shown in your listing, marked by me:


flash ~ $ cat /proc/bus/usb/devices

T: Bus=05 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#= 1 Spd=480 MxCh= 5
                                                    ^^^^^^^
<snip>

"Spd=480" is 480Mbps and that's USB2.  If it said "Spd=12", NOW you've
got USB1.1 (12Mbps), and now you know why they say USB2 is 40 times
faster than USB1.1 (480/12 = 40).  Simple, no?
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