I'm going to try bulk transfers this afternoon.

I also just tried doing high bandwidth interrupt
transfers. I thought that perhaps I could get
three transfers per microframe.
In /proc/bus/usb/devices I see this for my interrupt
endpoint:
E:  Ad=82(I) Atr=03(Int.) MxPS=3066 Ivl=125us

Note that 3066 is 3X1022 where 1022 was my base packet
size. Oddly, the wMaxPacketSize element of the
usb_endpoint_descriptor structure claims the size
is 5118 bytes. That is almost, but not quite 5*1022 (5120).
This is obviously a bug, and it definitely fails with
the -75 (OVERFLOW) status return in the callback.

When I use 3066 instead of the bogus 5118 the transfers
appear to happen, but now I get one call to my callback
every 3 milliseconds instead of every millisecond. So
it is still doing only one 1022 byte transfer per millisecond.

Richard


-- Richard Stover email: [EMAIL PROTECTED] Detector Development Laboratory http://www.ccd.ucolick.org UCO/Lick Observatory Natural Sciences Bldg. 2, Room 160 University of California Santa Cruz, CA 95064 USA



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