On Wed, 15 Aug 2007, Rogier Wolff wrote: > On Tue, Aug 14, 2007 at 05:23:04PM -0400, Alan Stern wrote: > > On Tue, 14 Aug 2007, Rogier Wolff wrote: > > > > > On Tue, Aug 14, 2007 at 10:23:27AM -0400, Alan Stern wrote: > > > > > The other external disk (also claimed to be full speed) seems to > > > > > achieve > > > > > transfer speeds of 20-30 KB which seems OK. > > > > > > > > If 400 KB/s is bad, how come 20-30 KB/s is OK? > > > > > > He probably means 20-30 M byte/sec. > > > > How could a full-speed device possibly transfer data at 20-30 MB/s? > > Because consumers confuse full speed (12) and high speed (480).
Irrelevant. Consumers can be as confused as they like; that won't make a full-speed device run at 20-30 MB/s. :-) Did you mean to say that Wim thought a device was running at full speed when it was actually running at high speed? That seems unlikely since his usbtree output lists no high-speed controllers. > My workstation upstairs shows: > > | > |- UHCI Host controller > | > |- UHCI Host controller > | > |- UHCI Host controller > | > -- UHCI Host controller > | | > | |- ALTERA IO BOARD 2.0 > | | > | -- USB HUB > | | > | |- CanoScan > | | > | |- USB <-> Serial > |- EHCI Host controller. > > Which means that I can connect a fast (highspeed) device to the wrong > port and have it perform badly. I doubt it, unless you mean one of the ports on your hub. This listing doesn't provide complete information, but most likely each of the ports on your computer is connected to both a UHCI controller and the EHCI controller. Alan Stern ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Linux-usb-users@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-users
