用php生成JQuery脚本

我正试图用php编写一个jquery函数，但该函数在编写到一半时停止了jquery函数的编写。当我启动while循环时，它似乎会导致内部服务器错误500

function loadSchedule() {
$id = $_SESSION['loginID'];
//query stuffs that works
$conn = getCon();
$res = $conn->query($qry);
echo "$(document).ready(function() {"
        ."$('#schedule').fullCalendar({"
        ."  header: {"
        ."  left: '',"
        ."  center: '',"
        ."  right: ''"
        ."},"
        ."defaultView: 'agendaWeek',"
        ."editable: false,"
        ."allDaySlot: false,"
        ."eventLimit: true," // allow "more" link when too many events
        ."events: [";
//problem starts here
while($rows = $res->fetch_assoc()){
    foreach (explode(',', $rows['DOW']) as $val){
        echo '{'
            .'title:"'.$rows['Course_code'].' '.$rows['number'].'",'
            .'start:"'.$rows['start'].'",'
            .'end: "'.$rows['end'].'",'
            .'dow: ['.getDayStr($val).'] '
            .'},';
    }
}                       
echo "]});});";

每当我注释掉while循环时，它就会工作，但除此之外它就会失败。如果我把它单独放在一个文件中，它可以很好地工作，但由于某种原因，它在放入脚本标记时失败了。