AT88SC1616C-SH ATMEL [ATMEL Corporation], AT88SC1616C-SH Datasheet - Page 13

• Manufacturer Part Number: AT88SC1616C-SH
• Description: Atmel CryptoMemory, 16Kbit
• Manufacturer: ATMEL [ATMEL Corporation]

12.
12.1
Password Verification
Passwords may be used to protect read and/or write access of any user zone. When a valid password is presented, it is
memorized and active until power is turned off, unless a new password is presented or RST becomes active. There are eight
password sets that may be used to protect any user zone. Only one password is active at a time, but write passwords give
read access also.
Authentication Protocol
The access to a user zone may be protected by an authentication protocol. Any one of four keys may be selected to use with a
user zone.
The authentication success is memorized and active as long as the chip is powered, unless a new authentication is initialized
or RST becomes active. If the new authentication request is not validated, the card loses its previous authentication and it
should be presented again. Only the last request is memorized.
Note:
Figure 12-1. Password and Authentication Operations
Password and authentication may be presented at any time and in any order. If the trials limit has been reached
(after four consecutive incorrect attempts), the password verification or authentication process will not be taken
into account
COMPUTE Challenge B
Device (Card)
Checksum (CS)
VERIFY WPW
VERIFY RPW
Card Number
Challenge B
VERIFY CS
Write DATA
VERIFY A
DATA
AUTHENTICATION
WRITE ACCESS
READ ACCESS
Atmel AT88SC1616C [SUMMARY DATASHEET]
COMPUTE Challenge A
Challenge A
VERIFY B
Read Password (RPW)
VERIFY CS
Write Password (WPW)
DATA
CS
Host (Reader)
2030LS−CRYPTO−12/11
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