How to use PHP with Scroller

I followed the Scroller example successfully:
http://datatables.net/release-datatables/extensions/Scroller/examples/simple.html

I want to use my PHP script to connect to a MS SQL database and return the correct JSON. I used PHP in other datatables but do not know how to use it with scroller.

How do I alter the following javascript to call a PHP file instead of the file 2500.txt?

          $(document).ready(function () {
                      $('#example').DataTable({
                           ajax: "../php/2500.txt",
                          deferRender: true,
                            dom: "frtiS",
                           scrollY: 200,
                         scrollCollapse: true
                      });
                   });