My Epson scanner now works - without USB 2

[Jeff Vian]

On Tue, 2006-03-28 at 18:03 +0100, James Wilkinson wrote:
> David Fletcher wrote:
> > This sort of problem seems to have been around for a while now. I've found a 
> > way to get mine to work with FC5, by disabling USB 2 support on the 
> > motherboard using a BIOS setting. So long as the scanner is connected to a 
> > motherboard USB connector and switched on BEFORE logging in.
> 
> This is probably a stupid question -- by "motherboard USB connector",
> you mean one at the back of the machine next to the keyboard and mouse
> sockets?
> 
> As I've got a pretty cheap case with USB sockets on the front.  If I
> plug in a "full-speed" (12 Mb/s) or "low-speed" (1.5 Mb/s) device, or if
> I rmmod ehci_hcd before plugging in a "hi-speed" (480 Mb/s) device, or
> if I plug in a hi-speed device through a USB 1.1 hub, then the USB ports
> work fine (but at no more than 12 Mb/s). But the ports don't seem to be
> able to handle 480 Mb/s.
> 
Some boards have different speed ports at different locations.
I have seen some with a pair of 1.1 ports and a pair of 2.0 ports on the
back, and depending on which motherboard connector you used for the
front panel connectors you could also get different speeds there.
Most of the newer boards are at least consistent with having all 2.0
ports and most newer cases are all 2.0 compliant.

Some older cases had front panel connectors that were built with 1.1
standards and may not be capable of running 2.0 so if they try it causes
errors.  Sometimes the ability to handle high speed devices is bios
dependent as well.


> Plugging in the same device to the USB sockets on the motherboard works
> perfectly.
> 
> Come to that, it could even be your USB cable...
> 
> James.
> 
> -- 
> E-mail address: james | These people are toast, and it is time to turn them
> @westexe.demon.co.uk  | over so that they are evenly roasted on both sides.
>                       |     -- AllParadox, on groklaw.net
>