Escalator or moving step assembly

The present invention relates to an escalator or a moving step assembly. An escalator or moving step assembly includes a control unit, a plurality of input/output units each for providing data concerning a respective one of a location and a function of the escalator, and a standard bus system. The input/output units are connected to the standard bus system for communicating therewith. The escalator also includes a plurality of security position switches each having at least one opening contact and a plurality of security slaves each associated with a respective one of the security position switches and being communicated with the standard bus system. A security monitor communicated with the standard bus system and operating in cooperation with the security slaves initiates an intervention in the operation of the escalator in the event that an opening contact of a security slave is opened.