On Sun, 18 Sep 2005, Jason D. Sommerville wrote: > On Sunday 18 September 2005 04:09 pm, Alan Stern wrote: > > Have you tried plugging other high-speed devices into that card? > > I've plugged in my usb 2.0 thumb drive to this card and it works correctly in > all ports. As I mentioned, I've also plugged the drive into my laptop where > it works correctly, so whether its hardware or software, I suppose it's a > combination of the card and the drive.
Sounds like it. It's a strange kind of fault, though. > I've done a little more testing, and if I plug the drive into ports 0,1 or 4 > (my own arbitrary numbering) it is recognized as a USB 1.0 device. Ports 2 > and 3 it connects as a 1.1 device. (I assume you mean that in ports 0, 1, and 4 it runs at high speed, whereas in ports 2 and 3 it runs at full speed. It will always be recognized as a USB 2.0 device no matter what port you use; you check this by looking at the "Ver=" field on the D: line in /proc/bus/usb/devices.) That certainly points to some sort of hardware-level problem. > > According to your log, the drive really does connect at full speed, not > > high speed. > > I don't know if it was in the log that I attatched, but in the messages log I > see: > > Sep 17 15:06:37 localhost kernel: usb 1-3: new full speed USB device using > ohci_hcd and address 5 > Sep 17 15:06:37 localhost kernel: usb 1-3: not running at top speed; connect > to a high speed hub > Sep 17 15:06:37 localhost kernel: scsi1 : SCSI emulation for USB Mass Storage > devices > > which suggests to me that somebody correctly knows it's a high speed device. Well, the device itself knows that it's capable of running at high speed, and it tells the computer. The computer recognizes that the device is currently attached on a full-speed link and warns you that you'd get better performance if it were attached to a high-speed link instead. > Further thoughts? Make sure never to plug it into ports 2 or 3. :-) Alan Stern ------------------------------------------------------- SF.Net email is sponsored by: Tame your development challenges with Apache's Geronimo App Server. Download it for free - -and be entered to win a 42" plasma tv or your very own Sony(tm)PSP. Click here to play: http://sourceforge.net/geronimo.php _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
