Hello Everyone,
I’m still kinda new to the whole Linux thing, so I have a general
question.
How do you find out if your machine has a USB 2.0 bus? After looking
around
the discussion list, I found the “lsusb” command as well as the note
that
USB 1.1 is “full speed” (running at 12 Mbps) while USB 2.0 is "high
speed
(running at 480 Mbps). When I run “sudo lsusb -vv”, within the long list
of
info, I find that I have 2 buses with the following parameters (I’m
assuming
these are the parameters that are important):
Bus 001 Device 001: ID 0000:0000
Device Descriptor:
bcdUSB 1.10
bDeviceClass 9 Hub
bDeviceSubClass 0 Unused
bDeviceProtocol 0 Full speed hub
Bus 002 Device 001: ID 0000:0000
Device Descriptor:
bcdUSB 2.00
bDeviceClass 9 Hub
bDeviceSubClass 0 Unused
bDeviceProtocol 1 Single TT
So I get that the first bus is 1.1, but even though it seems like the
second
bus is 2.0 , when I look further down into Configuration Descriptor ->
Interface Descriptor -> bInterfaceProtocol i see a value of “Full Speed
Hub”. I know the USRP works with this machine, so is Ubuntu just not
able
to fully recognize that bus 2 is “high speed”?
Also, I’m assuming that it doesn’t matter that I have only one USB 2.0
“bus”
even if I have two actual ports - both of them should run at 480 Mbps,
right?
Lastly, is there an easier way to figure out what speed your USB bus is
running at?
Thanks,
Martin G.