AT88SC3216CRF-MVB1G Atmel, AT88SC3216CRF-MVB1G Datasheet - Page 124

• Manufacturer Part Number: AT88SC3216CRF-MVB1G
• Description: CRYPTOMEMORY 32KBIT 16ZONE MVB
• Manufacturer: Atmel
• Series: CryptoMemory®, CryptoRF®r

Specifications of AT88SC3216CRF-MVB1G

• Rf Type: Read / Write
• Frequency: 13.56MHz
• Features: ISO1444-2, 1444-3, 32-kbits
• Package / Case: MVB Module
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

K.8.1. Key Index
K.9.
K.10. Passwords
K.11. Deactivating Encryption Communication Security
124
The Key Index byte of the Verify Crypto command selects the Key Set that the PICC uses to perform the Mutual
Authentication and Encryption Activation procedure.
Table 102.
Set User Zone and Checksums
The Mutual Authentication and Encryption Activation procedures can be performed before or after the Set User Zone
command is sent. It is not necessary to repeat the Mutual Authentication and Encryption Activation procedure when
changing User Zones unless the new User Zone requires a different Key Set. If Encryption Communication Security is
activated and the application later selects a User Zone that does not require Encryption, the PICC will remain in
Encryption Communication Security mode, User Zone data will be encrypted, and all of the Encryption mode
requirements will continue to apply.
When Encryption Communication Security is active the Host must supply a correct cryptographic checksum when
writing data to a User Zone. This is true even if the User Zone Access Register does not require Encryption for access
to the zone.
When Encryption Communication Security is active Passwords are encrypted during communications. The Host is
required to encrypt the three password bytes when sending the Check Password command. The PICC encrypts any
password bytes that are accessed with the Read System Zone command. The Host is required to encrypt any
password bytes when sending the Write System Zone command.
Once activated, the PICC will remain in Encryption Communication Security mode until a security error occurs, a new
Verify Crypto command is received, RF power is removed, or a DESELECT command or IDLE command is received.
In some applications it is necessary to deactivate Encryption Communication Security so that data can be written to a
User Zone that has open read/write access without the necessity of computing a cryptographic checksum. While there
are several possible ways to reset the cryptographic engine and exit the Encryption Communication Security mode, it is
recommended that the Send Checksum command be used for this purpose.
If the PICC receives a Send Checksum command containing an incorrect checksum, the PICC resets the cryptographic
engine, returns to Normal Communication mode, and returns a NACK response to the host. The AAC
incremented by the PICC when a bad checksum is received, so there is no penalty for using Send Checksum to exit
Authentication or Encryption mode.
AT88SC0808/1616/3216/6416CRF, AT88RF04C
Key Index
$00
$01
$02
$03
$10
$11
$12
$13
Key Index coding for the Verify Crypto command
All Other Values Are Not Supported
Secret Seed G0
Secret Seed G1
Secret Seed G2
Secret Seed G3
Session Encryption Key S0
Session Encryption Key S1
Session Encryption Key S2
Session Encryption Key S3
Key
i
register is not
5276C–RFID–3/09