random

var running = true;
var nextFrameDelay = 17;
var frameTime = 0;
var frameStart = window.performance.now();
var isPaused = true;

setInterval(function() {
    frameTime = window.performance.now();
    if ((frameTime - frameStart) < 17) {
        isPaused = true;
    } else {
        isPaused = false;
    }
    if (!isPaused) {
        console.log("17ms has elapsed");
        frameStart = window.performance.now();
        isPaused = false;
    }
}, 1);




var myVar = setInterval(function(){ myTimer() }, 1000);

function myTimer() {
    var d = new Date();
    var t = d.toLocaleTimeString();
    document.getElementById("demo").innerHTML = t;
}

function myStopFunction() {
    clearInterval(myVar);
}