var timerID = null;
var timerRunning = false;

function stopclock (){
if(timerRunning)
clearTimeout(timerID);
timerRunning = false;
}

function startclock () {
stopclock();
showtime();
}
function showtime () {
var now = new Date();
var hours = now.getHours();
var minutes = now.getMinutes();
var seconds = now.getSeconds()
var timeValue = "" +((hours >= 12) ? "ÏÂÎç " : "ÉÏÎç " )
timeValue += ((hours >12) ? hours -12 :hours)
timeValue += ((minutes < 10) ? ":0" : ":") + minutes
timeValue += ((seconds < 10) ? ":0" : ":") + seconds
document.write(timeValue);
timerID = setTimeout("showtime()",1000);
timerRunning = true;
}