Zig Zag Binary ix2 & i/2

var txt:TextField = TextField(addChild(new TextField()));
txt.text = "";
txt.width = 190;
txt.height = 400;
txt.multiline = true;

var count:int = 1;
function render():void{
	var line = int(count).toString(2);
	while(line.length < 31){
		line = "0" + line;
	}
    txt.appendText(line + "n");
	txt.scrollV= txt.maxScrollV;
}

addEventListener(Event.ENTER_FRAME, onCountUp);
function onCountUp(evt:Event):void {
	count *= 2;
	render();
	if (count ==0x40000000){
		removeEventListener(Event.ENTER_FRAME, onCountUp);
		addEventListener(Event.ENTER_FRAME, onCountDown);
	}
}
function onCountDown(evt:Event):void {
	count /= 2;
	render();
	if (count ==1){
		addEventListener(Event.ENTER_FRAME, onCountUp);
		removeEventListener(Event.ENTER_FRAME, onCountDown);
	}
}

The above animates a zig zag pattern in a TextField.