摘要 |
A motor rotational speed control apparatus is constructed by a control unit for performing an instruction to accelerate a rotational speed of a motor, an instruction to decelerate, or an instruction to maintain a rotational speed, a driving unit for driving the motor in accordance with an instruction outputted from the control unit, and first and second wires for transferring the instruction of the control unit to the driving unit. The control unit shows the instruction by a combination of signal levels of a first signal and a second signal and transmits the first and second signals to the driving unit through the first and second wires, and the driving unit drives the motor in accordance with the combination of the signal levels of the first and second signals. <IMAGE> |