A substrate processing apparatus having a station for loading and unloading substrates from the apparatus, includes an aperture closure for sealing a loading and unloading aperture of the station, a fluidic magazine door drive for removing a door of a substrate magazine and thus opening the substrate magazine and for operating the aperture closure to open the aperture, and sensor for mapping vertical locations of substrates mounted to the magazine door of the drive. The fluidic magazine door drive may include an encoder different from the sensor, the encoder being configured for determining the vertical location of the sensor.