| 摘要 |
PURPOSE:To enable to perform a counting without being affected by chattering, by a method wherein a theroretical sum and a theoretical product of outputs of two switches are found, one output sets an FF, the other resets the output of the FF, and so obtained output of the FF is counted. CONSTITUTION:With switches 7 and 8 repeating, in turn, to tune on and off through the rotation of a rotary switch, the outputs (a) and (b) of the switches 7 and 8 are added to an NOR circuit 11 and an AND circuit 12. Outputs c and d of the circuits 11 and 12 are added to RS-FF3. The outputs c sets an FF3 and the output d resets the FF3, whereby an output e of an FF-3 is completely prevented from being affected by chattering of the switches 7 and 8. The output e is added to a CK terminal of a binary counter 17 for counting. As a result, the counter 17 can always perform an accurate counting without being entirely affected by chattering of the switches 7 and 8. |
