PULSE PERIOD MEASURING SYSTEM USING MICROCOMPUTER

摘要

PURPOSE:To make it possible to set interrupt conditions such as the number of interrupts or the like during one loop, by determining an input pulse signal being the basis in the generation of an interrupt signal to measure a pulse cycle. CONSTITUTION:When an input signal IN1 comes to L, a counter unit 1 complets the counting of a signal IN1 during a duration H to hold a counted value. Because output ports P20-P22 are set to L, the output of an AND gate 6 is suplied to the port P13 as L and interrupt is applied. The ports P21, P22 are set to H and it is decided that signals other than the signal IN1 are not L while the counted value of the counter is read to calculate the period of the signal IN1. The port P20 is set to H and interrupt due to the signal IN1 is inhibited. As mentioned above, period measurement related to the signals IN2, IN3 is completed. The ports P21-P22 are set to L by releasing the same from setting H at every one loop treatment to make it possible to perform period measurement once at every one loop.