function myDatapoll(){

          $.ajax({

                  type : "GET",
                  url : '../myData.xhtml',
                  dataType : "json",
                  async : true,
                  cache : false,

                  success: function(data) {
                            if(data!=null){
                               if($("span[id='accBal-"+data.pID+"']").length>0){

                                   $("span[id='accBal-"+data.pID+"']").text(parseFloat(data.accBal).toFixed(2));
                               }else{
                                   $("#cash").html('<span id="accBal-'+data.pID+'">'+parseFloat(data.accBal).toFixed(2)+'</span>');
                               }
                           }
                       setTimeout('myDatapoll()',1000);
                  },
                  error : function() {

                  }
             });
      }

setInterval('myDatapoll()',1000);

function myDatapoll(){
    //same as before but remove the setTimeout
}