This should do what you are after,
package {
import fl.motion.easing.Linear;
import com.flashdynamix.motion.Tweensy;
import com.flashdynamix.motion.TweensyTimeline;
import flash.display.Sprite;
/**
* @author FlashDynamix
*/
public class TweensySmartRotate extends Sprite {
public var box : Sprite;
public function TweensySmartRotate() {
loop();
}
public function loop() : void {
var timeline : TweensyTimeline = Tweensy.to(box, {rotation:"-180"},
1, Linear.easeNone);
timeline.onComplete = loop;