| 摘要 |
<P>PROBLEM TO BE SOLVED: To adequately realize both high-speed inner processing and a broad-range operative space. <P>SOLUTION: An IC card 1 realizes the broad-range operative space by changing the speed of a CPU operation clock to a lower or medium one at a stage in which the IC card is captured (identified) by a reader/writer 2 or executes a small amount of calculation processing. The IC card 1 realizes the high-speed inner processing by changing the speed of the CPU operation clock to a higher one at stages at which the IC card executes a large amount of calculation processing, executes reading processing to read data, and executes writing processing to write the result of the calculation and the data, respectively. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
