text: #!/usr/bin/env python3
  
  import serial, sys, getopt
  
  usage = '''\nhexwriter [OPTION] -f FILE\nDefault operation is to use 115200 baud on /dev/ttyUSB0\nOPTIONS:\n-h displays usage\n-b baud rate\n-d device handle\n-f file name'''
  
  try:
  	opts, args = getopt.getopt(sys.argv[1:], 'b:d:f:h', ['baud=', 'device=', 'file=', 'help'])
  	
  except getopt.GetoptError:
  	print(usage)
  	sys.exit(2)
  
  baud_rate = 115200
  dev = '/dev/ttyUSB0'
  filename = ''
  
  for opt, arg in opts:
  	if opt in ('-h', '--help'):
  		print(usage)
  		sys.exit(2)
  	elif opt in ('-b', '--baud'):
  		baud_rate = arg
  	elif opt in ('-d', '--device'):
  		dev = arg
  	elif opt in ('-f', '--file'):
  		filename = arg
  	else:
  		print(usage)
  		sys.exit(2)
  
  if filename == '':
  	raise Exception("No file given\n%s" % (usage))
  	sys.exit(2)
  
  ser = serial.Serial()
  ser.baudrate = baud_rate
  ser.port = dev
  
  try:
  	ser.open()
  except SerialException:
  	print('Could not open device: %s' % (dev))
  	sys.exit(2)
  
  try:
  	f = open(filename, 'rb')
  except IOError:
  	print("Could not read file: %s" % (filename))
  	sys.exit(2)
  
  with f:
  	byte = f.read(1)
  	while byte != b"":
  		ser.write(byte)
  		byte = f.read(1)
  
  