ser = serial.Serial(0, 19200, timeout=0.3, parity='N',rtscts=True, xonxoff=True)
while True:
    char = ser.readline(size=1)
    if char == '\x01':
        print "Nouvelle trame"
        da_size = ser.read(size=1)
        i_size = int(da_size.split('\x')[0])
        da_ payload = ser.read(size=i_size)
        print "Ma trame :", da_payload