| 摘要 |
PROBLEM TO BE SOLVED: To ensure a stable operation of a counter device even to an input signal that has an optional clock cycle by counting the number of clocks included in the input signal set in an optional time interval, storing the count value of the rise or fall timing of a periodic signal, and updating the count value to the prescribed value if the count value is coincident with the stored value. SOLUTION: A count part 2 counts the number of clocks included in a clock signal, and a count value storage part 3 stores the count value of the part 2 in a count value storing part 8 at the rise of the synchronizing signal set in a time interval equivalent to four cycles of a periodic signal. When a count value decision part 4 decides the matching between the count value of the part 2 and that stored in the part 8, the part 4 outputs a decision signal in addition to the count value. Based on the decision signal, a count value updating part 5 updates the current count value of the part 2 to the value that is decided by subtracting 1 from the count vale stored in the part 8. Thus, a block using the clocks of different speeds can be shared. |
