| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a clock signal generation circuit and a clock signal generation method that can supply a clock signal of a predetermined frequency to a peripheral circuit irrespective of the frequency of a clock signal supplied to a CPU. <P>SOLUTION: The clock signal generation circuit, which generates from a first clock signal input into a CPU a second clock signal of a predetermined frequency input into a peripheral circuit, includes: a first clock generation section for generating the first input clock signal from a clock signal output from an oscillator according to at least either of a multiplication ratio and a division ratio both input from without; a reference value calculation section for calculating a reference value for the creation of the second clock from the first clock signal; and a second clock generation section for generating the second clock according to a result of comparison of a count value of the first clock signal with the reference value. When at least either of the multiplication ratio and the division ratio is changed to change the frequency of the first clock signal, the reference value calculation section recalculates the reference value. <P>COPYRIGHT: (C)2013,JPO&INPIT |
