Why write/read once, I need replug the usb device ?

[erikaemma]

I use the bulk endpoint to read/write.
But if I read/write once, when I rerun the script, it will:

usb.core.USBError: [Errno 110] Operation timed out

THE FULL CODE:

self.__dev = usb.core.find(idVendor=self.__USB_VID, idProduct=self.__USB_PID)
for i in self.__dev[0].interfaces():
    if self.__dev.is_kernel_driver_active(i.bInterfaceNumber):
        self.__dev.detach_kernel_driver(i.bInterfaceNumber)
self.__dev.set_configuration(1)
cfg = self.__dev.get_active_configuration()
interface = cfg[(1, 0)]
self.__epi = usb.util.find_descriptor(
    interface,
    custom_match=lambda e: usb.util.endpoint_direction(e.bEndpointAddress) == usb.util.ENDPOINT_IN
)
self.__epo = usb.util.find_descriptor(
    interface,
    custom_match=lambda e: usb.util.endpoint_direction(e.bEndpointAddress) == usb.util.ENDPOINT_OUT
)
//...
return self.__epi.read(size_or_buffer)

[jonasmalacofilho]

Most likely because your program doesn't comply with the protocol and device specs/requirements (e.g. missing messages or delay).

You could also have hit a firmware bug.