ActionScript 3.0 :: Listen To A Custom Event In Various Classes At Same?

I'm using a electronic device to dispatch events within AS3.
 
short explanation: -->

Think of these events as a KeyboardEvent.My point is to dispatch an Event (like a Key that is being pressed) so I can listen to this event on EVERY Class I need to.I'm not sure how to instantiate or listen to these events correctly =/
 
I mean: I want to be able to listen to the key that is been pressed as if that was a global event every Class can receive...
 
long explanation: --> I'm doing something like this:

1) created a (main) Class that extends a Sprite.

2) created a class (KeyboardInput) that extends the main class.

3) created a class (KeyMap) that extends EventDispatcher.

4) created a class (HomeScreen) that extends a Sprite.
 
 My FLA file is associated to the KeyboardInput Class.This Class creates a listener for the KEY_DOWN KeyboardEvent and instantiate the KeyMap Class that dispatches a CustomEvent:
 
stage.addEventListener(KeyboardEvent.KEY_DOWN,function(evt:KeyboardEve nt):void { keymap = new KeyMap(); keymap.setKey(String.fromCharCode(e.charCode)) });[code].....