A motor has windings and a control device, which applies appropriately one-way current to each of the windings. Two full-pitch windings, which are located adjacently to both ends of an A-phase stator magnetic pole, and driving transistors are connected in series to each other to supply an A-phase current component, thereby exciting an A-phase magnetic flux component passing through the A-phase stator magnetic pole, resulting in generation of torque. This excitation is also applied to other phases. The respective stator magnetic poles can be excited selectively, and voltages across both ends of the serially connected windings become a voltage for corresponding magnetic flux components which should be provided by the windings, thus providing a more simplified motor structure and higher motor performance. The windings and transistors can be used commonly in two phases, providing an improved usage rate, thus making the motor more compact in size and reducing manufacturing cost.