Arduino 脉冲数

pulseIn()

pulseIn(pin, value)
pulseIn(pin, value, timeout)

Parameters

pin: the number of the pin on which you want to read the pulse. (int)

value: type of pulse to read: either HIGH or LOW. (int)

timeout (optional): the number of microseconds to wait for the pulse to be completed: the function returns 0 if no complete pulse was received within the timeout. Default is one second (unsigned long).

Returns

the length of the pulse (in microseconds) or 0 if no pulse is completed before the timeout (unsigned long)

Example






int pin = 7;

unsigned long duration;



void setup()

{

  pinMode(pin, INPUT);

}



void loop()

{

  duration = pulseIn(pin, HIGH);

}

int pin = 7;
unsigned long lowduration;
unsigned long highduration;
unsigned long timeperiod;

void setup()
{
 pinMode(pin, INPUT);
digitalWrite(pin, HIGH);
}

void loop()
{
 lowduration = pulseIn(pin, LOW);
 highduration = pulseIn(pin, HIGH);
 timeperiod = lowduration + highduration;
}