var count = 0;
var timer;
var timerOn = false;

function timedCount() {
  count++;
  timer = setTimeout(function(){
    timedCount()
  }, 1000);
}

function doTimer() {
  if (!timerOn) {
    timerOn = true;
    timedCount();
  }
}

function stopCount() {
  clearTimeout(timer);
  timerOn = false;
}

Just a counter

Count with setTimeout

JavaScript