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Reads a pulse (either HIGH or LOW) on a pin. For example, if value is HIGH, pulseIn() waits for the pin to go HIGH, starts timing, then waits for the pin to go LOW and stops timing. Returns the length of the pulse in microseconds.
The timing of this function has been determined empirically and will probably show errors in longer pulses. Works on pulses from 10 microseconds to 3 minutes in length. Note that this function will not return until a pulse is detected.
pin: the number of the pin on which you want to read the pulse. (int)
value: type type of pulse to read: either HIGH or LOW. (int)
the length of the pulse (in microseconds)
int pin = 7; unsigned long duration; void setup() { pinMode(pin, INPUT); } void loop() { duration = pulseIn(pin, HIGH); }
Corrections, suggestions, and new documentation should be posted to the Forum.
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