[pyusb-users] pyUSB - delayed sending to the device? / Ubuntu 19.10

[Kevin G. <ele...@my...>]

Hello,

I am re-using a subject line from the mailing list archive, by user 
Marcin, in an attempt to append to that thread.

https://sourceforge.net/p/pyusb/mailman/pyusb-users/thread/15e9538f-386f-a637-ce2b-5eea3d04bd76%40gmail.com/

I had a simlar issue recently with a simple test application which 
opened a device and sent some OUT packets (to 512 size endpoint) thus:

..open device..
for i in range(n):
   dev.write(2,bytearray(os.urandom(512))
..close device..

On windows, this worked fine for any 'n' but on Linux only even 'n' 
worked correctly. For odd 'n' one packet was always dropped/stuck.
As Marcin suggested, ending with dev.reset() seemed to flush this stuck 
packet and fixed the issue.
But using reset in this way seems wrong.
After opening the device calling
dev.clear_halt(2)
Seemed to fix the issue.

Regards
Kevin