Oppure
<script type="text/javascript"> data = <?php echo(date('yy/m/d H:i:s')); ?> alert(data); </script>
<script type="text/javascript"> data = <?php echo "date('yy/m/d H:i:s');"; ?> alert(data); </script>
<script type="text/javascript"> data = "<?php echo date('yy/m/d H:i:s'); ?>"; alert(data); </script>