
Page
51
of
77
Copyright © Access-IS 2020
7.11 MIFARE Ultralight-C authenticate - part 1
Use this command to perform the first part of the MIFARE Ultralight-C authentication.
Note: This command is applicable ONLY to MIFARE Ultralight-C cards and fails if executed on
other MIFARE card types.
7.11.1 MIFARE Ultralight-C command bytes
MIFARE command bytes
Command header
Command
code
[0x00]
[0x24]
MIFARE Ultralight-C Authenticate part 1
7.11.2 MIFARE Ultralight-C response bytes
MIFARE Ultralight-C response bytes
Response header
Response code
Block number
Response
cryptogram(1)
Status bytes
[0x00]
[0x25]
Ignored
9 bytes starting
with
[0xAF]
[0x90][0x00]
Success
Failure
(1)
This field is present only if the command is successful. Refer to page 55 for information on
MIFARE failure status codes.
Note: Once the NFC module receives a command, it waits for 250 milliseconds for another
command to arrive. If no command arrives, it resets the MIFARE card. This
interval, the ‘Command
Wait Time
’, is configurable using the Set NFC timings command (on page 59).
The NFC reader resets the MIFARE card after the
‘Command Wait Time’ has expired, and any
authentication done before this event is lost.
This means that you must send the next Authenticate part-2 command after a successful
Authenticate part-1 command before the
‘Command Wait Time’ expires.
If you want to preserve the authentication for a longer period, without changing the
‘Command Wait
Time
’, send the ‘MIFARE get media type command’ (on page 39) periodically to keep the session
active.
7.11.3 Example
This command performs authentication (part 1) on an Ultralight-C card.
USB
Command:
[0x00][0x24]
Response:
[0x00][0x25][0x00][0xAF][0x19][0xA0][0xC9][0xF4][0xC2][0x19]
[0x16][0x2F][0x90][0x00]