Guangdong IC card application / 4442IC card manufacturers 4442 IC card Description: 4442 256 byte encryption card, there is read data, write data, protect data and cryptographic operations. Electrical performance? ● 256 × 8 位 EEPROM? ● byte addressed directly? ● Write Protection bit low address 32 byte data set unrecoverable? ● 32-bit protected-bit? ● write data operation marks the end? ● comply 7816-3 ● reset the standard response time byte erase and then write:?? standard value 25ms ● least 10,000 write-erase cycles ● Data retention:? 10 years is widely used in social security, driver management, banks, restaurants and hotels, retail, health insurance, health care, communications, set-top boxes, identification and other areas of IC card. 4442IC Card Function Description: ● three bytes of user passwords. ? ● check the correct password before all the data can only be read, not rewritten. ? ● check the correct password can be changed after the data, including passwords and then inside. ? ● error counters, the initial value of 3, check the error code 1, then subtract 1, if the counter value is 0, the card is automatically locked, the data can only be read out, can no longer change the password can not be checked; if When non-zero, there is a password check is correct, restore to the initial value 3. ? ● write-protected area (first 32 bytes) of each byte can be individually write protected post write-protected content can not be changed (ie, curing data). Programmer's Note: 1. Remove the write-protected area of ??32 bytes, programmers actionable only 224 bytes, and write-protected area, such as the opportunity to write only once, generally do not use. 2. Note that each rewrite password, only the next card after power-on password to take effect. 3. 3-byte password that is 24-bit, general ambassador password is '255255255', converted to hexadecimal for six F that 'FFFFFF'