from pirc522 import RFID

import RPi.GPIO as GPIO
import sys

GPIO.setwarnings(False)

rdr = RFID()

while True:
  (error, tag_type) = rdr.request()
  if not error:
    (error, uid) = rdr.anticoll()
    if not error:
      tag_id = ''.join(hex(x)[2:].zfill(2) for x in uid)
      print(tag_id)
      sys.stdout.flush()

rdr.cleanup()