millis fonction

Projects Programming
5

This code might not compile but gives you an idea:

unsigned long startMillis = 0;
unsigned long stopMillis = 0;
unsigned long duration = 0;
byte infraredPin  = 1;

void setup()
{
Serial.begin(9600);
}

void loop()
{
  if(digitalRead(infraredPin) == 0)
  {
    startMillis = millis();
    while(digitalRead(infraredPin) == 0)
    {
      //Do nothing and wait
    }
    stopMillis = millis();
    duration = stopMillis - startMillis;
    Serial.println(duration);
  }
}