var centri
	function apriCentri(){
		if (centri != null) {
			if (!centri.closed) {
				window.parent.centri.close();
			}	
		}	
		w = 740
		h = 580
		X = (screen.width-w)/2;
		Y = (screen.height-h)/2;
		centri = window.open('http://www.roland.it/arframe.html','CENTRI_ASSISTENZA','scrollbars=no,resizable=yes,width=' + w +',height=' + h + ',status=no,location=no,toolbar=no,top=' + Y + ',left=' + X);		
		return;
	}