AJAX post returns 500 error

I fixed the issue. Seems like it could not handle it via post, so changed it to run using get requests.

Code:

//AJAX call to submit and install
$(document).ready(function(){
     var formdata = <?php print json_encode($this->input->post(NULL, TRUE)); ?>;
     console.log(formdata);
     $.ajax({
         type: "GET",
         url: "<?php print site_url('install/runci'); ?>",
         data: formdata,
         success: function(msg) {
             console.log(msg);
         }
     });
});