codice:
<style type="text/css">
.textbox{
border:none;
font-family:verdana, arial;
font-size:10px; 
color:#000080; 
font-weight:bold
}
.testo{
font-family:verdana, arial;
font-size:12px;
color:#000080;
font-weight:bold;
} 
</style>
<head>
<title>Orario Dinamico</title>
<script language="JavaScript" type="text/JavaScript">
var timerID = null;
var timerRunning = false;
function stopclock (){

        if(timerRunning)

                clearTimeout(timerID);

        timerRunning = false;

}

function showtime () {

        var now = new Date();

        var hours = now.getHours();

        var minutes = now.getMinutes();

        var seconds = now.getSeconds()

        var timeValue = " " + ((hours >12) ? hours -12 :hours)

        timeValue += ((minutes < 10) ? ":0" : ":") + minutes

        timeValue += ((seconds < 10) ? ":0" : ":") + seconds

        timeValue += (hours >= 12) ? " p.m." : " a.m."

        document.clock.face.value = timeValue;

        
        timerID = setTimeout("showtime()",1000);

        timerRunning = true;

}
function startclock () {
stopclock();
showtime();
}
</script>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
</head>
<body bgcolor="white" onload="startclock(); timerONE=window.setTimeout">
<div align="center"> 
  <form name="clock" id="clock" onsubmit="0">
    <p align="right">
    <input type="text" name="face" class="textbox" size="12" value="" /> </p>
  </form>
</div>



</body>
</html>