Re: After first USB release unable to communicate with USB device
venkat wrote:
> Am Using Libusb 0.1 to test my printer code. The code runs as expected
> with 2.6.32 kernel in debian 6. However, After debian 8 upgrade we
> notice that printer responds for very first read operation after reboot,
> For rest of command executions READ fails with*ENODEV*.
>
> By doing this, I lost communication with the device
>
> |1. USB_OPEN()
> 2. Claim the interface
> 3. USBBulkWriteOnEP (FW version request fro my device)
> 4. Release the interface
> 5. Claim the interface
> 6. USBBulkReadOnEP
> 7. Release the interface
> 8. Usb_close()
> 9. Loop on GOTO1.
>
> |
>
> *However, if i insert USB_RESET after every read operation the command
> work..*
Hi,
fist I am not sure what Debian has to do with it, as you have low level
issues.
Second I think the device interfaces changed, so better check your code
against the kernel version in debian8.
Third If you stick to the same kernel 2.6.32 (this is not clear from your
statement) in debian 8 it might be some other library
Last provide debug output - I am sure there are no fortune tellers here
In my opinion you have some newer kernel and the usb part changed often in
the past
regards
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