var timer = new Timer();
timer.interval(10000).addCallback(get);

function get(){
     var url = 'playlist.php';
     var pars = 'r=1';
     var target = 'currPlay';
     var myAjax = new Ajax.Updater(target, url, {method: 'get', parameters: pars});
}

function init(){
	get();
	timer.start();
}

Event.observe(window, 'load', init, false);