請問這錯在哪里﹖

把
setTimeout("mouseMov()",100);  
去掉：<head><title></title></head>
<body onmousemove="mouseMov();">
<form name="form1" id="form1">
<input type="text" name="bu1" size=4 value=33>
<input type="text" name="bu2" size=4 value=44>
</form>
<script language="javascript">
  function mouseMov(){                            
    document.forms[0].bu1.value=event.screenX;
    document.form1.elements[1].value=event.screenY;
    //setTimeout("mouseMov()",100);  
  }
</script>
</body>
</html>