mrmstn
commented
6 years ago https://www.nxp.com/docs/en/application-note/AN10927.pdf
Well, there should be a "uid" returned, but the uid[0] will be 0x88, which says that the uid is not complete yet.
Heres a small example of how to get 7 and 10 bit uids. It is just a small draft since I had the same issue. I'll open a pull request later
class RC522Reader:
def __init__(self):
self.reader = RFID()
def force_read_id(self):
while True:
self.reader.wait_for_tag()
(error, tag_type) = self.reader.request()
if error:
continue
print("Tag detected")
(error, uid) = self.read_uid()
if error:
continue
card_uid = ''
for part in uid:
card_uid += ("%X" % part)
return card_uid
def read_uid(self):
# https://www.nxp.com/docs/en/application-note/AN10927.pdf
(error, uid) = self.reader.anticoll()
if error:
return error, None
if uid[0] is not 0x88:
return False, uid
error = self.reader.select_tag(uid)
full_uid = uid[1:3]
print("UID is not yet complete")
(error, cl2) = self.read_cl2()
if error:
return error, None
if cl2[0] is not 0x88:
full_uid.extend(cl2)
return False, full_uid
full_uid.extend(cl2[1:3])
(error, cl3) = self.read_cl3()
if error:
return error, None
full_uid.extend(cl3)
return False, full_uid
def read_cl2(self):
back_data = []
serial_number = []
serial_number_check = 0
self.reader.dev_write(0x0D, 0x00)
serial_number.append(0x95)
serial_number.append(0x20)
(error, back_data, back_bits) = self.reader.card_write(self.reader.mode_transrec, serial_number)
if not error:
if len(back_data) == 5:
for i in range(4):
serial_number_check = serial_number_check ^ back_data[i]
if serial_number_check != back_data[4]:
error = True
else:
error = True
return error, back_data
def read_cl3(self):
back_data = []
serial_number = []
serial_number_check = 0
self.reader.dev_write(0x0D, 0x00)
serial_number.append(0x97)
serial_number.append(0x20)
(error, back_data, back_bits) = self.reader.card_write(self.reader.mode_transrec, serial_number)
if not error:
if len(back_data) == 5:
for i in range(4):
serial_number_check = serial_number_check ^ back_data[i]
if serial_number_check != back_data[4]:
error = True
else:
error = True
return error, back_data
JCQ81
Hi, Tags with 7-byte id's do not seem to be read. These tags are detected, but the id is not returned. Am I doing something wrong? Thanks!