Help with the basics of interfacing with flash

I’ve been trying to follow the tutorial on how to interface the arduino with flash8 i’ve been using the example with turning on the LEDS and turning them off, well their code works but mine will not, whatever i try, i’m getting so aggravated that I’m putting my mercy to the forums for help. how do i send a simple command to turn an led on that is attached to port 9, i’m using the arduino.as file and trying all sort of different things, i want it to go on when i push a button in flash. i’ve tried a.send(9) i’ve tired a.send(this.9), i don’t understand how their code works and mine doesn’t here is theirs: function setupBoard() {
trace(“Connection established. Now setting up LEDs…”);
// Each physical LED gets a virtual copy in Flash

for (var i=2;i<=9;i++) {

// Associates a pin with each movieclip
var mc:MovieClip = _root[“led”+i];
// Stores the digital i/o pin number for later use
mc.pin = i.toString();

var owner = this;
mc.onPress = function() {
// Send the pin data to Arduino, telling it what pin to turn on
owner.a.send(this.pin);

// Turn all virtual LEDs OFF
for (var i=2; i<=10; i++) {
_root[“led”+i].gotoAndStop(1);
}
// Now turn the selected virtual LED ON
_root[“led”+this.pin].gotoAndStop(2);
}
}
}

i don’t understand how thiers works, i understand getting inputs to work with flash, just not outputs.