AS3 Formatted Stopwatch Functionality

import flash.utils.getTimer;
 
startTimer.addEventListener(MouseEvent.CLICK, onStartTimer_CLICK);
stopTimer.addEventListener(MouseEvent.CLICK, onStopTimer_CLICK);
 
var startTime:int; 
var stopTime:int;
 
function onStartTimer_CLICK(event:MouseEvent):void {
	startTime = getTimer();
	trace("startTime: "+startTime);
}
 
function onStopTimer_CLICK(event:MouseEvent):void {
	stopTime = getTimer();
	trace("stopTime: "+stopTime);
	var timeDiff:int = stopTime - startTime;
	trace("timeDiff: "+timeDiff);
	trace(formatTime(timeDiff));
}
 
 
function formatTime($time:uint):String {
	var formattedTime:String;
	var hrs:uint;
	var mins:uint;
	var secs:uint;
	var ms:uint;
 
	var msAfterHrs:uint = $time % ((1000 * 60) * 60);
	hrs = ($time - msAfterHrs) / ((1000 * 60) * 60);
 
	var msAfterMins:uint = msAfterHrs % (1000 * 60);
	mins = (msAfterHrs - msAfterMins) / (1000 * 60);
 
	var msAfterSecs:uint = msAfterMins % 1000;
	secs = (msAfterMins - msAfterSecs) / 1000;
 
	ms = msAfterSecs;
 
	if (ms == 100) {
		ms = 0;
	}
 
	//formattedTime = formatNumber(hrs, 2)+":"+formatNumber(mins, 2)+":"+formatNumber(secs, 2)+"."+formatNumber(ms, 3);
	formattedTime = formatNumber(hrs, 2)+"h "+formatNumber(mins, 2)+"m "+formatNumber(secs, 2)+"s";
 
	return formattedTime;
}
 
function formatNumber($num:uint, $digits:uint):String {
	var formattedNum:String;
 
	if ($digits == 2) {
		if ($num < 10) {
			formattedNum = "0"+$num;
		} else {
			formattedNum = String($num);
		}
	} else if ($digits == 3) {
		if ($num < 10) {
			formattedNum = "00"+$num;
		} else if ($num < 100) {
		formattedNum = "0"+$num;
		} else {
			formattedNum = String($num);
		}
	}
	return formattedNum;
}