Set up a standard airlock for atmosphere on both sides. Configure the pressures in the first two lines of the script. '''Before exporting the script or resetting the IC, make sure the airlock is cycled to the outside (inner door closed, outer open)'''. The LED serves as trigger for both cycling the airlock and skipping each phase, hence should be placed inside the airlock. The airlock should be a single frame to avoid leftover atmosphere after depressurization. For larger airlocks place the sensor on the far side from the vents. The script supports [[Blast Doors]], but since they lack a door handle you will need a button on each side (outside) of the airlock. Connect a [[Logic Writer]] to each button and use it to toggle the LED.