| 摘要 |
PURPOSE:To omit the waiting time and to improve the date processing speed by controlling a driving motor for revolution of magnetic disk through a revolution synchronizing circuit which indicates whether the revolving state of the magnetic disk is fast or slow with a revolution synchronizing signal and the signal which detects a specific sector of the disk. CONSTITUTION:If a sector counter 25 counts ''0'' when the revolution synchronizing signal is delivered from a revolution synchronizing signal generating part 27 provided to an external controller, a revolution synchronizing circuit 26 controls a motor driving power amplifier 23 so that a spindle motor 21 revolves by inertia. Thus the rotational frequency of the motor 21 is slightly reduced, and therefore the counter 25 counts 127, for example, when the next revolution synchronizing signal is delivered. Then the circuit 26 controls the amplifier 23 so as to accelerate the motor 21. The counter 25 counts ''0'', for example, when the next revolution signal is delivered. Thus the acceleration control is discontinued, and the motor 21 is revolved again by inertia. |
