usb - How to send hid data to device using python / pywinusb? -

i'm trying use pywinusb send output report pic18f4550. device can receive data, , i've tested c# application, worked fine. also, can read data device pywinusb fine, have problem trying send data.

here's code i'm running:

from pywinusb import hid  filter = hid.hiddevicefilter(vendor_id = 0x0777, product_id = 0x0077) devices = filter.get_devices()  if devices:     device = devices[0]     print "success"  device.open() out_report = device.find_output_reports()[0]  buffer= [0x00]*65 buffer[0]=0x0 buffer[1]=0x01 buffer[2]=0x00 buffer[3]=0x01  out_report.set_raw_data(buffer) out_report.send() dev.close() 

it produces error:

success traceback (most recent call last):   file "c:\users\7user\desktop\usb pic18\out.py", line 24, in <module>     out_report.send()   file "build\bdist.win32\egg\pywinusb\hid\core.py", line 1451, in send     self.__prepare_raw_data()   file "build\bdist.win32\egg\pywinusb\hid\core.py", line 1406, in __prepare_raw_data     byref(self.__raw_data), self.__raw_report_size) )   file "build\bdist.win32\egg\pywinusb\hid\winapi.py", line 382, in __init__     raise helpers.hiderror("hidp error: %s" % self.error_message_dict[error_code]) hiderror: hidp error: data index not found 

here code , works msp430f chip running ti's datapipe usb stack. hid input , output endpoints act custom data pipe allowing me send 64 bytes in format want exception of first byte being id number (defined ti) decimal 63 , second byte being number of pertinent or useful bytes in packet (64 byte max packet) first 2 bytes described above. took me while figure out because of lack of documentation. few examples come pywinusb hard learn @ best. anyways here code. working micro should you.

        filter = hid.hiddevicefilter(vendor_id = 0x2048, product_id = 0x0302)     hid_device = filter.get_devices()     device = hid_device[0]     device.open()     print(hid_device)       target_usage = hid.get_full_usage_id(0x00, 0x3f)     device.set_raw_data_handler(sample_handler)     print(target_usage)       report = device.find_output_reports()      print(report)     print(report[0])      buffer = [0xff]*64     buffer[0] = 63      print(buffer)      report[0].set_raw_data(buffer)     report[0].send() 

one area may screwing here:

out_report = device.find_output_reports()[0] 

try using "out_report = device.find_output_reports()" without "[0]" @ end. use

out_report[0].set_raw_data(buffer) 

and finally

out_report[0].send() 

hope helps out.