摘要 |
An intrinsic cipher code peculiar to each IC card is written and stored in EEPROM serving as a writable non-volatile memory in an IC card, as well as a routine for performing collation with the intrinsic cipher code before a test program is executed being stored in a read-only memory as to allow access to the test program when agreement is established. An attempt can thus be made to improve security for access to the test program. |