Hi, On Tuesday 27 November 2001 10:19, you wrote: > Quoting Victoria W. <[EMAIL PROTECTED]>: > > If I try to use two cam-sevices (pwc oder others) at the same time, > > only one of them is working. > > Each time, I try to access the other one, I get: > > > > hub.c: already running port 1 disabled by hub (EMI?) > > > > I have tried it with several different uhci-hardware - even if I use an > > external hub. It's everytime the same. (it does not depend on > > usb-uhci.o or uhci.o) > > Only with an usb-ohci.o-hardware it works. > > I tried running several cameras off of ONE controller (either OHCI or > UHCI), and it didn't work well. Not with Philips cameras though. I saw > occasional "freezes" of the picture that required restart of the v4l > viewer or replugging the camera (probably not.) > > This is likely because my cameras *always* requested full Isoc bandwidth > (transfers of 1022 bytes), and that is entire USB frame. Do it often > enough - and cameras love that (for FPS's sake) - and one camera easily > consumes entire bandwidth of the USB bus (which is not that much to begin > with).
Well, that depends of course on the requested image size. At small sizes and high compression, you can run 5 Philips cameras simultaneously on one controller. Have you tried playing with the compression parameter? - Nemosoft _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
