I am designing a controller for an elevator. The elevator can be at one of two floors: Ground or First. There is one button that controls the elevator, and it has two values: Up or Down. Also, there are two lights in the elevator that indicate the current floor: Red for Ground, and Green for First. I am stuck on how do l add the SR latches which open and close the door when it reaches the desired elevator floor ? How can l include this in my FSM diagram ?