Combining millis with button sensing

Projects Programming
5

if you use Bounce2 to do the heavy lifting:

#include <Bounce2.h>

const byte LedPin = 13;
const byte InputPin = 5;

const unsigned long MaxRunTime = 5000;

unsigned long startMillis;

Bounce input;


void setup(){
  pinMode(LedPin, OUTPUT);
  input.attach(InputPin, INPUT_PULLUP);
}

void loop(){
  input.update();
  
  if(input.rose()){
    startMillis = millis();
    digitalWrite(LedPin, HIGH);
  }
  else if(input.fell() || millis() - startMillis >= MaxRunTime){
    digitalWrite(LedPin, LOW);
  }
}

Only note, the write to low ma be executed multiple times. Not a problem for digitalWrite() but might be for other stuff you place there.