| 摘要 |
An IC card includes a first semiconductor memory, such as a 256K bit RAM, for storing main data; a second semiconductor memory, such as a 64K bit EEPROM, for storing physical information concerning the IC card, e.g., size, capacity, and access time; a control circuit for selectively enabling operation of the first and second semiconductor memories; an address BUS connected to the first and second semiconductor memories; a data BUS connected to the first and second semiconductor memories; and a decoder connected to the address BUS and the second semiconductor memory for decoding a write control signal for the second semiconductor memory using part of an address signal from the address BUS and delivering a decoded write control signal to the second semiconductor memory to control storing of data in the second semiconductor memory. Consequently, the area in the second semiconductor memory is divided into a non-writable region which does not permit overwriting of stored data and a writable region which permits overwriting of stored data.
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