A magnetic resistance memory apparatus capable of implementing various levels and a method of driving the same are provided. An electric motor is disposed radially about the spindle and includes a stationary stator and a rotor rotatable about the rotational axis relative to the stator. In a second embodiment, a slave device acting as a bridge receives a burst of indefinite length and translates the bus request into one with a predetermined fixed length for application to a device controller. The oscillation detecting unit receives a signal output from an oscillator through the input pin, and stores a predetermined value in the register cell when it is detected that the signal oscillates.