Compared with AT88SC1608 and AT88SC153, the most prominent feature of AT88SC0104 is that all transmitted data are transmitted in cipher text, which ensures the security of stored data. ATMEL Corporation has now recommended that the AT88SC1608 and AT88SC153 be no longer used in new product development. In fact, AT88SC0104C~25616C have many similarities with AT88SC1608 and AT88SC153, such as access permission register and write lock control register. The operation principle of each device in the AT88SC0104C~25616C protocol authentication card series is exactly the same, and each configuration area changes with the capacity of the card.
1. main feature
(1) The working voltage is 2.7~5.5V; the clock frequency is up to 1.5MHz; it conforms to the ISO/IEC 7816-3 synchronization protocol.
(2) 256×8 bit configuration area, 4×32×8bit~16×2048×8bit storage unit. Multiple application partitions with the same security level and the same password can be used in combination. Each partition is controlled by the read password and write password (8 sets of passwords, one for each set of read passwords and one for write passwords, each password is 3 bytes), and the error count is 8 times. If the user partitions are merged, the read and write passwords point to the same set of passwords.
(3) Data security protection function: 64bit authentication protocol; ciphertext and verification method; ciphertext stream transmission method; protocol authentication error count; read and write access control password; password error counter; access rights can be configured by partition; voltage and clock Frequency monitoring.
(4) Repeated erasing times: 100,000 times, data storage: 100 years.
2. Package and Pinout
The package form and pin function of the AT88SC0104C~25616C protocol authentication card are shown in Figure 1.
Card Packages DIP-8 and SO-8 Packages
3. Memory composition of AT88SC0104C~25616C protocol authentication card
Bucket 0 1 2 3 4 5 6 7 Address
User partition 0~P 32~2048 bytes 000H~QH
Configuration area 256 bytes 00H~FFH
Note: P is the maximum number of user partition, 0~15; Q is the maximum byte address, 018H~7F8H.
Which partition to access is determined by the partition number selected. The access of the user partition memory is controlled by the control logic circuit, and the protection function is configured by the access authority register AR, the password authority register PR and the password in the configuration area during initialization (ie issuance).
4. Protocol Authentication Process
The protocol authentication process of the AT88SC0104C~25616C protocol authentication card is similar to that of the AT88SC1608. Compared with AT88SC1608, its protocol authentication process (ie steps 1~3) is similar. When the ciphertext data is transmitted, the security of the data is higher due to the transmission of the checksum. The protocol authentication process of the AT88SC0104C~25616C protocol authentication card is as follows:
1 Send card number NC → Computational challenge A
2 Check A; Calculate Challenge B ← Send challenge A
3 Send challenge B → Check B
4 Check read password ← read password
5 transmit data → Receive data
6 send checksum → Receive and check the checksum
7 Verify write password ← write password
8 Receive data ← transmit data
9 Receive and check the checksum ← send checksum
10 write data
There are three basic communication modes between the AT88SC0104C~25616C protocol authentication card and the IC card reader, and the default configuration is the standard mode after power-on. A successful authentication operation activates authentication mode. The encryption mode is activated after the authentication operation is successful.
Communication encryption mode of AT88SC0104C~25616C protocol authentication card: