Help tweek my parallax code?

1

I am trying to do a slight parallax effect. Right now, the code i’m using takes my object from the far left of the screen, to the far right. I only want it to move like 200 pixels away from the center of the screen.

How can I tweek this code in order to achieve this?

Thanks.

onClipEvent (enterFrame) {
if (_root.mainVarX == 0) {
// horizontale position
homeX = (-_root._xmouse*1+1100);

} else {
	
	homeX = (-_root.mainVarX +1100);
	
}
thisX = _x;

diffX = homeX-thisX;

if (_root.mainVarX == 0) {
	moveX = diffX/5;
	
} else {
	moveX = diffX/5;
	
}


	_x = thisX+moveX;

}