AT88SC0104CA_11 ATMEL [ATMEL Corporation], AT88SC0104CA_11 Datasheet - Page 38

• Manufacturer Part Number: AT88SC0104CA_11
• Description: Atmel CryptoMemory Specification Datasheet
• Manufacturer: ATMEL [ATMEL Corporation]

8.12
8.12.1 Functional
Verify Crypto: $B8
Figure 8-15. Verify Crypto Command Functional Description
When the device receives the verify crypto command, it computes a challenge based on the received random number, Q, the
internally stored associated cryptogram, C
the associated attempts counter. It then compares the computed challenge with the challenge sent by the host. If the
challenges match, the device computes and writes a new C
authentication process and updates the attempts counter accordingly.
Key index:
Data :
8 random bytes
8 challenge bytes
b0000_00nn : Secret Seed G
b0001_00nn : Session Encryption Key S
Q : Host random number, 8 bytes
CH : Host challenge, 8 bytes
Host
Command
Key Index
Q1
Q2
Q3
Q4
Q5
Q6
Q7
Q8
CH1
CH2
CH3
CH4
CH5
CH6
CH7
CH8
0
-G
3
i
, and secret seed, G
0
-S
Device
3
Atmel AT88SC0104CA/0204CA/0404CA/0808CA [Datasheet]
i
and S
i
(or session encryption key, S
i
. The device utilizes the success or failure information of the
i
). The device also decrements
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