On Fri, 11 Oct 2002, anton wilson wrote: | Is there a guarantee that USB core and the HC will report timing problems? | For instance, if I'm "chaining" ISO transfers to run every millisecond, do | USB core and the HC always know if we miss that 1 millisecond transfer for | some reason? If so, how does it communicate this failure with the upper level | driver?
I think that one or more of the HCD developers should answer part of this. One of the uhci hcd's used to report "missed frame timing" or something like that on missed isoc frames. However, USB isoc does not have any data delivery guarantees. It can drop data or garble data. It was intended for use with things like audio/video, where dropping a frame every once in a while shouldn't matter. I don't recall any such reporting of this to an upper-level driver. -- ~Randy "In general, avoiding problems is better than solving them." -- from "#ifdef Considered Harmful", Spencer & Collyer, USENIX 1992. ------------------------------------------------------- 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
