olin_piclist@embedinc.com (Olin Lathrop) wrote:
> Dave Tweed wrote:
> > Now, it may be that outbound bulk transfers don't have to wait for a 1
> > ms boundary, but the status request that tells the scheduler that
> > there's inbound data waiting in the device definitely does.
> 
> I'm not in my office now where the USB spec is, but I thought the
> scheduler was free to use any remaining slot time after isochronous and
> other hard-scheduled activity on bulk transfers in any way it wants to.
> Are you saying that the scheduler is not allowed to re-poll a bulk
> transfer device to see if it has input data during left over time?  I
> don't remember any such limitation, but it's been a while since I read
> thru the spec.

No, the spec. doesn't rule it out AFAIK, but I've never seen a host
scheduler that spontaneously polls devices more than once per frame.

-- Dave Tweed

P.S. I'll see you this afternoon.
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