You may perform this work with two ways: pass it directly like described in sample #1 or use an anonymous function like its shown in sample #2.

gistfile1.js

    <script type="text/javascript">
/* Source: http://www.apphp.com/index.php?snippet=javascript-pass-parameters-in-setinterval */
    // sample #1
    setInterval('alert_function(1)', 1500);
     
    // sample #2
    setInterval(function(){ alert_function(10); }, 1500);
     
    // user's alert function
    function alert_function(val){
        alert("Passed parameter is: " + val);
    }
    </script>