| 摘要 |
PURPOSE:To prevent such a foul action where an outsider rewrites card balance information in a higher amount by inhibiting the balance rewriting action in case the balance read out of a stored fair card is lager than the new balance. CONSTITUTION:When a stored fair card is put into a card processing mechanism 1, various types of information including the balance information, etc. are read by a reading head. The balance information is stored temporarily in a memory 4 via a CPU 3 and at the same time the desired information is sent to a host controller 6. Thus the CPU 3 is set under a reception waiting state and then receives the new balance information from the controller 6 to compare it with the balance information stored and read out. If the new balance is smaller than the stored balance, the information is rewritten by the rewriting head of the mechanism 1. While no rewriting action is carried out if the new balance is larger than the stored one and the card is returned. Thus it is possible to avoid such a foul action where an outsider rewrites intentionally the balance information. |
