try{
    xmlhttp = new XMLHttpRequest();
}catch(ee){
    try{
        xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
    }catch(e){
        try{
            xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
        }catch(E){
            xmlhttp = false;
        }
    }
}

var timerID = null;
function img() {
	clearTimeout(timerID);
	showImovel();
	timerID = setTimeout("img()", 10000); // 10 segundos
	timerRunning = true;
}

function showImovel() {
	var div = document.getElementById("divimovel");
	
	xmlhttp.open("POST", "select.php");
	xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
	xmlhttp.setRequestHeader("Cache-Control", "no-store, no-cache, must-revalidate");
	xmlhttp.setRequestHeader("Cache-Control", "post-check=0, pre-check=0");
	xmlhttp.setRequestHeader("Pragma", "no-cache");
	xmlhttp.send("");
	
	xmlhttp.onreadystatechange = function() {
		if (xmlhttp.readyState == 4) {
			if (xmlhttp.status == 200) {
				div.innerHTML = xmlhttp.responseText;
			}
		}
	}
}