| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a non-contact IC card in which both quickness and stability are made compatible in bi-directional communication with an external device by switching an operation clock driving an IC chip. <P>SOLUTION: When abnormal end is caused in bi-directional communication with the external device 20, the operation clock of a non-contact IC card 11 is decreased by one stage in the case of the next communication, and bi-directional communication with reduced power consumption can be executed. On the other hand, when generated electric energy by an electromagnetic wave to be received from the external device 20 is sufficient, and bi-directional communication with the external device 20 continuously succeeds over the predetermined specific number of times, the operation clock of the non-contact IC card 11 is increased by one stage in the case of the next communication, so that higher speed processing can be achieved. <P>COPYRIGHT: (C)2008,JPO&INPIT |
