| 摘要 |
PURPOSE: To provide a noise elimination circuit whose circuit constitution is simple. CONSTITUTION: This circuit is composed of a switch 1, an inverter 3, AND gates 4 and 7, latch circuits 5 and 8, input/output ports 6 and 9 and a CPU 10. The output of the latch circuit 5 or 8 is periodically monitored from the side of the CPU 10, it is judged that the contact point of the switch 1 is shifted only when one of the latch circuits 5 and 8 is set continuously for plural times and a prescribed processing is executed. Since chattering noise accompanying the transition of the contact point of the switch 1 is absorbed in the latch circuits 5 and 8, it is not outputted to the CPU 10. |
