Abstract: The invention relates to a device (1) for detecting a stack height of sheets (21) stacked in an input and/or output tray (2) of an apparatus, said device comprising a feeler (10) cyclically controlled and driven by means of a drive unit (12) and a control unit toward the sheet stack (21) in the stacking direction into a sensing position, and a sensor (11) detecting the sheet stack height and recognizing the sensing position of the feeler.

Abstract: In a reproduction apparatus embodying a marking engine including a logic and control unit for controlling the operation of the reproduction apparatus and at least one accessory, such as a sorter, binder, stacker, folder, or the like, associated with the marking engine, a communication system for automatic identification of accessories associated with the marking engine. The communication system discloses a processor associated respectively with each accessory. The processor includes an identification of the associated accessory. A communication bus is interconnected between the logic and control unit of the marking engine and the processors of each respective accessory. A timing circuit, responsive to power up of the marking engine and associated accessories, automatically enables the processors of each respective accessory, in sequential order, to relay accessory identification provided by the respective processors, in such sequential order to the logic and control unit of the marking engine.