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Tom
01-14-2003, 06:06 AM
I've just downloaded knoppix build 2003-01-01

It booted fine and detected all my USB 2.0 peripherals (harddrive, CD-R/RW, hub, pcmcia host controller) but they've come up only at USB 1.1 speeds.

Does anyone know how I can make it run at the full USB 2.0 speed?

The harddrive is so slow at 12 Mbps!
Thanks

Dave_Bechtel
01-14-2003, 08:43 AM
' modprobe ehci-hcd '

From /usr/src/linux-2.4.20-xfs/Documentation/usb/ehci.txt
[[
The EHCI driver is used to talk to high speed USB 2.0 devices using
USB 2.0-capable host controller hardware. The USB 2.0 standard is
compatible with the USB 1.1 standard. It defines three transfer speeds:

- "High Speed" 480 Mbit/sec (60 MByte/sec)
- "Full Speed" 12 Mbit/sec (1.5 MByte/sec)
- "Low Speed" 1.5 Mbit/sec

USB 1.1 only addressed full speed and low speed. High speed devices
can be used on USB 1.1 systems, but they slow down to USB 1.1 speeds.

USB 1.1 devices may also be used on USB 2.0 systems. When plugged
into an EHCI controller, they are given to a USB 1.1 "companion"
controller, which is a OHCI or UHCI controller as normally used with
such devices. When USB 1.1 devices plug into USB 2.0 hubs, they
interact with the EHCI controller through a "Transaction Translator"
(TT) in the hub, which turns low or full speed transactions into
high speed "split transactions" that don't waste transfer bandwidth.

At this writing, this driver has been seen to work with implementations
of EHCI from (in alphabetical order): Intel, NEC, Philips, and VIA.
]]


I've just downloaded knoppix build 2003-01-01

It booted fine and detected all my USB 2.0 peripherals (harddrive, CD-R/RW, hub, pcmcia host controller) but they've come up only at USB 1.1 speeds.

Does anyone know how I can make it run at the full USB 2.0 speed?

The harddrive is so slow at 12 Mbps!
Thanks