RFID RC522 Clone Script Unicode Error

Question

I've set up a RC522 Card on my pi using This Tutorial and hacked together the Read.py and Write.py scripts into a Clone.py script:

#!usr/bin/env python

import RPi.GPIO as GPIO
from mfrc522 import SimpleMFRC522

reader = SimpleMFRC522()

try:
    print("Scan Card Now")
    id, text = reader.read()
    print("Current ID:")
    print(id)
    print("Place Card for Write, Then Press ENTER")
    input("")
    reader.write(text)
    print("Write Complete")

Which works just fine when testing on blank cards. However, when I tried to clone an old hotel keycard I get:

Traceback (most recent call last):
  File "clone.py, line 16 in <module>
    reader.write(text)
  File "/usr/local/lib/python3.7/dist-packages/mfrc522/SimpleMFRC522.py", line 60 in write
    id, text_in = self.write_no_block(text)
  File "/usr/local/lib/python3.7/dist-packages/mfrc522/SimpleMFRC522.py", line 78, in write_no_block
    data.extended(bytearray(text.ljust(len(self.BLOCK_ADDRS) * 16).encode('ascii')))
UnicodeEncodeError: 'ascii' codec cant encode characters in position 1-2: ordinal not in range(128)

What can I do to fix this?

Answer 1

Ah, your hotel card might contain non ASCII characters, say Unicoded Chinese. So you need to decode the Unicoded Chinese characters each of which is denoted by two bytes. Of course hotel cards usually use other tricks to punish the bad guys trying to clone.