pseudo.txt

Main:
    Init memory for floor direction. 
    Init memory for floor storage
    Set up flags for calls

While:
At a given floor
    From current floor +- (direction) to max/min
    Check for calls from those floors

    If floor is a destination or is called in same direction
    Open doors. Check for hold open or hold close
    If not
    Move in direction

If no calls, 
    Clear direction. 
    Or just keep flip flopping directions looking for calls
If top/bottom 
    reverse direction