| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an IC chip, an IC card, and an operation method of the IC chip that can avoid a stop of a CPU operation even when an internal oscillator provided on the IC chip has a fault. <P>SOLUTION: A CPU of the IC chip according to the present invention reads an identifier from a non-volatile memory when timing of switching from an external clock signal to an internal clock signal arrives, performs an operation for executing a processing instruction using the external clock signal if the read identifier is a first identifier indicating inoperability by the internal clock signal, and performs the operation for executing the processing instruction by switching from the external clock signal to the internal clock signal if the read identifier is a second identifier indicating operability by the internal clock signal. <P>COPYRIGHT: (C)2012,JPO&INPIT |
