Demos/Device/ClassDriver/GenericHID/HostTestApp/test_generic_hid_libusb.py

   1 #!/usr/bin/env python
   2
   3 """
   4              LUFA Library
   5      Copyright (C) Dean Camera, 2018.
   6
   7   dean [at] fourwalledcubicle [dot] com
   8            www.lufa-lib.org
   9 """
  10
  11 """
  12     LUFA Generic HID device demo host test script. This script will send a
  13     continuous stream of generic reports to the device, to show a variable LED
  14     pattern on the target board. Send and received report data is printed to
  15     the terminal.
  16
  17     Requires the PyUSB library (http://sourceforge.net/apps/trac/pyusb/).
  18 """
  19
  20 import sys
  21 from time import sleep
  22 import usb.core
  23 import usb.util
  24
  25
  26 def get_and_init_hid_device():
  27     device = usb.core.find(idVendor=0x03EB, idProduct=0x204F)
  28
  29     if device is None:
  30         sys.exit("Could not find USB device.")
  31
  32     if device.is_kernel_driver_active(0):
  33         try:
  34             device.detach_kernel_driver(0)
  35         except usb.core.USBError as exception:
  36             sys.exit("Could not detatch kernel driver: %s" % str(exception))
  37
  38     try:
  39         device.set_configuration()
  40     except usb.core.USBError as exception:
  41         sys.exit("Could not set configuration: %s" % str(exception))
  42
  43     return device
  44
  45
  46 def send_led_pattern(device, led1, led2, led3, led4):
  47     # Report data for the demo is LED on/off data
  48     report_data = [led1, led2, led3, led4]
  49
  50     # Send the generated report to the device
  51     number_of_bytes_written = device.ctrl_transfer(  # Set Report control request
  52         0b00100001,  # bmRequestType (constant for this control request)
  53         0x09,        # bmRequest (constant for this control request)
  54         0,           # wValue (MSB is report type, LSB is report number)
  55         0,           # wIndex (interface number)
  56         report_data  # report data to be sent
  57     );
  58     assert number_of_bytes_written == len(report_data)
  59
  60     print("Sent LED Pattern: {0}".format(report_data))
  61
  62
  63 def receive_led_pattern(hid_device):
  64     endpoint = hid_device[0][(0,0)][0]
  65     report_data = hid_device.read(endpoint.bEndpointAddress, endpoint.wMaxPacketSize)
  66     return list(report_data)
  67
  68
  69 def main():
  70     hid_device = get_and_init_hid_device()
  71
  72     print("Connected to device 0x%04X/0x%04X - %s [%s]" %
  73           (hid_device.idVendor, hid_device.idProduct,
  74            usb.util.get_string(hid_device, 256, hid_device.iProduct),
  75            usb.util.get_string(hid_device, 256, hid_device.iManufacturer)))
  76
  77     p = 0
  78     while (True):
  79         # Convert the current pattern index to a bit-mask and send
  80         send_led_pattern(hid_device,
  81                          (p >> 3) & 1,
  82                          (p >> 2) & 1,
  83                          (p >> 1) & 1,
  84                          (p >> 0) & 1)
  85
  86         # Receive and print the current LED pattern
  87         led_pattern = receive_led_pattern(hid_device)[0:4]
  88         print("Received LED Pattern: {0}".format(led_pattern))
  89
  90         # Compute next LED pattern in sequence
  91         p = (p + 1) % 16
  92
  93         # Delay a bit for visual effect
  94         sleep(.2)
  95
  96 if __name__ == '__main__':
  97     main()