MN63Y1208 Datasheet, PDF (58/120 Pages) Panasonic Semiconductor – Built-in 4-Kbit FeRAM non-volatile memory with fast write and low power consumption

Chapter 4 RF Communication Mode
4.3.8.6 Data
For encrypted communication, the structure of data block for READ and WRITE commands is slightly different
from the ISO/IEC7816-4 command specification. Figure 4-26 shows the data block structure.
(1) Plaintext (unencrypted) communication treats all block data as actual data.
(2) In encrypted communication, the first 16 bytes of data is IV (Initial Vector) used for encryption, following
16×n bytes of data is actual data, and the last 16 bytes is MAC value for Message Authentication Code
(MAC).
Size specified by the Lc or Le field
(1) Plaintext
(unencrypted)
communication
DATA
1 x n bytes (n: integer)
Actual data
(2) Encrypted
communication
Size specified by the Lc or Le field
16 bytes
DATA
16 x n bytes (n: integer)
16 bytes
IV
Actual data
MAC value
Figure 4-26 Data Block Structure
Note: Setting the data length to a value other than 16×n bytes in encrypted communication causes the RFID
to respond with an error.
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