Introduction to Contact 4428 White Card

1、 Main indicators

1024 byte EEPROM

1024 byte write protected area (fixed data)

A 2-byte password with 8 error counts

Temperature range: -35 ℃~80 ℃

At least 100000 erase cycles

At least 10 years of data retention period

2、 Function description:

1. SLE4428 has a capacity of 1K bytes and an address space of 0-1023.

2. All data, except for the password, can be read in any situation, and the password can be read after verification.

3. All data, including the password itself, can be written or changed after verifying the correct password.

4. All data can be write protected by byte, and after write protection, the data is fixed and cannot be changed under any circumstances.

5. There is a password error counter. The address is 1021. The initial value is 8. If there is a password verification error once, it will be reduced by 1. If the counter value is 0, the entire card's data is locked and can only be read out, not written or changed, and password verification cannot continue; If it is not 0, it only needs to be checked correctly once, and the counter will return to its initial value.

6. The password length is 2 bytes, and the addresses are 1022 and 1023. There are a total of 216 combinations, and until the password is verified correctly, the result of reading these two addresses is "00", which cannot be written or changed; After verifying the password correctly, the password can be read or changed, and it will remain valid until the card loses power.

7. Unique code. The addresses 21-26 are the user codes for the card. Our company can provide users with a globally unique user code that has been registered with SIEMENS to maximize their benefits. The unique code of the current company is 6D 77 36 36 33 XX (hexadecimal), with an ASCII code of MW663x. The 6th byte XX will be allocated to users within the range of 00 to FF. This code cannot be changed after being solidified and written.

8. The addresses 0-7, 21-26 have been solidified by the manufacturer before leaving the factory and cannot be changed.

9. Regarding the protection bit, the corresponding address protection bit read out only has two values: 0 and non-0. If it is 0, it indicates that it is already protected and cannot be written again; If not 0, it indicates that it is not protected and can be written again.

4. Notes:

1. SLE4428 has three security mechanisms: user password, unique code, and fixed write. If the password is not verified correctly, then

Unable to write data, once the written data is write protected (fixed), it cannot be changed again. Using a unique code as the system

The identification of the IC card used in the system can prevent counterfeit cards of the same model from entering the system.

1. The SLE4428 card can read the entire card's data without a password, so it is important to pay attention to content encryption during design to prevent attackers from identifying the data format.

2. The entire card is not partitioned, and once the password is verified to be correct, data can be written or modified to any address. Therefore, when designing, attention should be paid to appropriately solidifying the data and encrypting the data content to prevent unintentional data damage or illegal data changes.

3. After verifying the password correctly, it can be read out. Therefore, during the design process, the program should be able to prevent saboteurs from illegally interrupting the program and directly reading passwords to steal them.

3、 Storage Area Allocation: