import serial

ser = serial.Serial(
    port='/dev/ttyUSB0',
    baudrate=3000000,
    parity=serial.PARITY_NONE,
    stopbits=serial.STOPBITS_ONE,
    bytesize=serial.SEVENBITS,
    timeout=0.1
)

one = 0xfe
zero = 0xe0
stop = 0xfe

status = bytes([zero, zero, zero, zero, zero, zero, zero, zero, stop])
poll = bytes([zero, zero, zero, zero, zero, zero, zero, one, stop])

ser.write(status)
ret=ser.read(30)
print(' '.join('{:02x}'.format(x) for x in ret))

while(1):
    ser.write(poll)
    ret=ser.read(50)
    print(' '.join('{:02x}'.format(x) for x in ret))
    if(ret[8] & 0xE0):
        print("A")
    if(ret[9] & 0xF0 == 0x70):
        print("B")
    if(ret[10] & 0x0F == 0x0e):
        print("Z")
    ser.flush()