| 摘要 |
PURPOSE:To improve the durability of this card reader/writer and to shorten its transaction time by reading out data from a card, comparing the read data with the precedently read data and storing the compared result and the current read data in a storage part to reflect the stored contents to a sense command. CONSTITUTION:When a read command has been executed, the preceding read data stored in the storage part are compared with the current read data. When both the data are the same as the result of comparison, the read state is held, and when respective data are different from each other, the read state is reset, the reset state is stored as control information so as to reflect the stored control information to a sense command. Thereby, the coincidence of the card can be checked only by outputting the sense command prior to writing and card reading operation can be made unnecessary. Consequently, the driving frequency of the reader/writer can be reduced, its durability can be reduced due to the reduction, and since the sense command does not follow card reading operation, the transaction processing time can also be shortened. |
