On Monday 28 October 2002 04:01 pm, Johannes Erdfelt wrote: > On Mon, Oct 28, 2002, anton wilson <[EMAIL PROTECTED]> wrote: > > On Friday 25 October 2002 06:36 pm, Johannes Erdfelt wrote: > > > On Fri, Oct 25, 2002, anton wilson <[EMAIL PROTECTED]> wrote: > > > > In a USB driver, I'm chaining ISO urbs by resubmitting the URBS in > > > > the completion handler. I also time the calls to the urb completion > > > > handlers using do_gettimeofday(). Most of the time, the time between > > > > interrupts is at most 1.01 ms, but occasionally there may be a 2 ms > > > > time inbetween interrupts. By occasional I mean 1 or 2 times every 10 > > > > seconds. Is this normal behaviour? And what kinds of things could > > > > cause an additional 1 ms delay between calls to the completion > > > > handler? > > > > > > What HC are you using? What kernel? > > > > linux 2.4.18 with 0(1) - preemptive and low-latency - > > UHCI > > How many Isochronous buffers are you scheduling at one time? > > Which UHCI driver? >
the usb-uhci module v1.275 ... I'd say 4 per device. 2 read and 2 write I'm not quite sure if enqueuing all 4 at once is necessary to achieve sends and recieves every ms. That's how the driver was before it was handed to me... The urbs are re-submitted in the completion handler. 3 devices are being used right now. Anton > JE > > > > ------------------------------------------------------- > This sf.net email is sponsored by:ThinkGeek > Welcome to geek heaven. > http://thinkgeek.com/sf > _______________________________________________ > [EMAIL PROTECTED] > To unsubscribe, use the last form field at: > https://lists.sourceforge.net/lists/listinfo/linux-usb-devel ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
