A detector and method for detecting a synchronization servo mark in a data stream of mass data storage device has a matched filter to receive the data stream. The paper sorting device for the image forming apparatus has a rotating shaft which is rotated by a driving force from a driving force source, a hollow shaft into which the rotating shaft is slidably inserted so that the hollow shaft rotates with, and is reciprocated on, the rotating shaft, and reciprocating means for reciprocating the hollow shaft. The method can also include detecting a first response to the first request, the first response originating from a first of a plurality of peripheral devices of the wagering game machine.