Quoting Matthias Murra <[EMAIL PROTECTED]>: > Commenting on my own post ... > > >I have switched ports back and forth, with the same result: The mouse works, > >the keyboard doesn't. :-/ > > Well, not quite true. I had booted into W2K to try something out, then > hot-unplugged the USB mouse and the USB keyboard, switched USB ports (that > is, put both devices back in), et voilą, the keyboard worked! Reboot to Linux: > the keyboard worked! Switched off the laptop, booted Linux again: keyboard > not working anymore ... It seems that it is _only_ working if I unplug the > keyboard while the system is running and then plug it back in, although that > is no guarantee that it continues to work after a reboot (sometimes it > does, sometimes it doesn't). > > So the issue seems to be shaky hardware, so I'm still puzzled what > exactly is the nature of the problem. I'm even more inclined to point > towards the laptop BIOS now, since no piece of hardware seems to be > toasted. Maybe I should bring this issue up on the Toshiba support forum.
Some (many!) USB hosts, when powered up, raise the USB power voltage very slowly. Some USB devices have poorly designed reset circuitry. When combined, some USB hosts (computers) can not initiate reset of the device if the device was already plugged in before the computer was turned on. I have this problem with some Philips chips, and Philips itself had to release an errata document with a fairly complicated external reset circuit. The easy solution is to use a self-powered hub, but not all of them work. You need a hub that *only* supports self-powered mode, and that would be a hub with more than 4 ports. The relay inside the hub applies the stable power to all ports instantly, and it causes the reset to work correctly. Those are just side effects of a very complicated mess that is called USB. It is just too difficult and expensive to make good USB devices. Plugfests are a very bad sign; a correct implementation of a correct standard would not require them. Dmitri -- "MSDOS didn't get as bad as it is overnight -- it took over ten years of careful development." (By [EMAIL PROTECTED])
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