<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>time</title>
<script>
var interval;
function ttt(){
var text = document.getElementById("time");
var today = new Date();
var h = today.getHours();
var m = today.getMinutes();
var s = today.getSeconds();
var str = "now time : "+h+" h "+m+" m "+s+" s ";
text.innerHTML = str;
interval = setTimeout("ttt()",1000);
}
function stop(){
clearTimeout(interval);
}
</script>
</head>
<body onload="ttt()">
<p id="time">show time</p><br />
<button onclick="ttt()">START</button>
<button onclick="stop()">STOP</button>
</body>
</html>
