[sane-devel] sequence usb commands send, receive

[Henning Meier-Geinitz]

Hi,

On 2006-04-29 13:55, gerard klaver wrote:
> I have a question about usb commands.
> I have for example the following sequence:
> 
> send urb 5, send urb 6, send/receive urb7, send/receive urb8, receive
> urb 5, receive urb6
> 
> At this moment i don't know how te handle this.
> send urb 5, 6 no problem, send/receive urb 7, 8 no problem, but how to
> handle to receive urb 5 and 6?.

As far as I know, at least the stable libusb doesn't provide support
for async io. Even if it did, I'm not sure if it would work with
"Out-of-order" URBs. IIRC, this didn't work with SCSI either?

Does your USB device really depend on this order?

Bye,
  Henning