var XMLHttpRequestObject = false;

  if (window.XMLHttpRequest) {
  XMLHttpRequestObject = new XMLHttpRequest();
  }
  else if (window.ActiveXObject) {
  XMLHttpRequestObject = new ActiveXObject("Microsoft.XMLHTTP");
  }
  function pedirDatos(fuenteDatos, divID)
  {
  if(XMLHttpRequestObject) 
  {
  var obj = document.getElementById(divID);
  XMLHttpRequestObject.open("GET", fuenteDatos);
  XMLHttpRequestObject.onreadystatechange = function(){
  if (XMLHttpRequestObject.readyState == 4 && XMLHttpRequestObject.status == 200) 
  {
  obj.innerHTML = XMLHttpRequestObject.responseText;
  }
  }
  XMLHttpRequestObject.send(null);
  } 
  }