ACS ACR122L, User Manual

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ACR122L – Communication Protocol
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Version 1.03
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Page 51 of 57
Step 4. Write (Mifare compatible Write) the content of Page
04 with the data “AA BB CC DD” .
HOST -> 02 6F 1A 00 00 00 00 01 00 00 00
HOST -> FF 00 00 00 15 D4 40
01 A0 04 AA BB CC DD 00 00 00 00 00 00 00 00 00 00 00 00
[Checksum] 03
RDR -> 02 00 00 03 (Waiting the Tag)
RDR -> 02 80 05 00 00 00 00 01 01 00 00
RDR -> D5 41 [00] 90 00 [Checksum] 03
Note: This command is implemented to accommodate the established Mifare 1K/4K infrastructure.
We have to assemble the data into a 16-byte frame. The first 4 bytes are for data, the rest of the bytes
(12 ZEROS) are for padding. Only the page 4 (4 bytes) is updated even through 16 byte are sent to
the reader.
Step 5. Read the content of Page 04 again .
HOST -> 02 6F 0A 00 00 00 00 01 00 00 00
HOST -> FF 00 00 00 05 D4 40
01 30 04 [Checksum] 03
RDR -> 02 00 00 03 (Waiting the Tag)
RDR -> 02 80 15 00 00 00 00 01 01 00 00
RDR -> D5 41 [00] AA BB CC DD 05 06 07 08 09 10 11 12 13 14 15 16 90 00 [Checksum] 03
In which, Block Data = AA BB CC DD 05 06 07 08 09 10 11 12 13 14 15 16
Note: Only page 4 is updated. Pages 5, 6 and 7 remain the same.
Step 6. Halt the tag (optional).
HOST -> 02 6F 08 00 00 00 00 01 00 00 00
HOST -> FF 00 00 00 03 D4 44
01 [Checksum] 03
RDR -> 02 00 00 03 (Waiting the Tag)
RDR -> 02 80 05 00 00 00 00 01 01 00 00
RDR -> D5 45 [00] 90 00 [Checksum] 03
Note:
Please refer to the Mifare Ultralight C specifications for more detailed information.
Byte Number 0 1 2 3 Page
Serial Number SN0 SN1 SN2 BCC0 0
Serial Number SN3 SN4 SN5 SN6 1
Internal/Lock BCC1 Internal Lock Lock 2
OTP OTP0 OTP1 OTP2 OTP3 3
Data read/write Data0 Data1 Data2 Data3 4
Data read/write Data4 Data5 Data6 Data7 5