| 摘要 |
<P>PROBLEM TO BE SOLVED: To secure an operation coping with the occurrence of noise without applying loads on software or the like, even when the frequency of an input signal is changed at any timing, and to prevent a reflection time lag. <P>SOLUTION: A first input signal masking period N is set, and the edge of the first input signal is counted by a second input signal. When the counted value shows the masking period N, a masking signal for the first input signal is generated, and the final counted value X or a value X+1 is held. Next, whether or not the final counted value X or the value X+1 is continued is checked, and when the check result is affirmative, returning to a step S102, and the subsequent processing is repeated, when the result is negative, a final counter value Y larger than the value X or a value Y+1 is held, then, the first input signal masking period N is automatically updated to a period M. Thereafter, the edge of the first input signal is counted by the second input signal, and when the counted value shows the period M, a changed masking signal for the first input signal is generated by a masking signal changing circuit. <P>COPYRIGHT: (C)2007,JPO&INPIT |
