| 摘要 |
The smart card carries three elements: an Electrically Erasable Programmable Read Only Memory - EEPROM, a control circuit and galvanic contacts. The card is inserted in a user machine, e.g. a cash machine, payment machine, telephone, etc. to perform financial transactions. Each digit of a number held in the memory is held in a five bit section (20) of the memory. As the least significant bits (26, 27) of the memory are changed most often during transactions, they are the most likely to fail. The controller for the present card has monitoring facilities which detect failures in the operation of the memory elements. If an element is faulty, the control system "shifts" the number up the memory by two elements (21). If faults continue to occur, further shifts (22 to 25) take place.
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