HPS USB stack API change
Hans Petter Selasky
hselasky at c2i.net
Thu Jun 14 09:56:25 UTC 2007
I'm planning to add another argument to "usbd_start_hardware()", which is a
delay value that gives the delay in microseconds or maybe milliseconds before
the transfer is actually queued. This can be used to reduce the polling rate
on BULK-IN transfers among other things, to reduce the overall power usage,
and to safely create infinite polling loops without fearing BUS overusage in
case of failure conditions.
usbd_start_hardware(xfer, 200000); //200 ms delay
A delay value of zero indicates no delay.
I plan to implement this re-using the timeout callout.
Any comments ?
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