| 摘要 |
PURPOSE:To decrease an access time by obtaining a seek amount from an object track value and a present track position, converting the amount into a sheek time, and generating a signal accelerating/decelerating a motor from the comparison between it and a phase adjusting time. CONSTITUTION:When an interface 1 receives a data D1, a signal S1 is generated and registers 2, 3 store an objective track value TRK1 in the signal D1 and an object sector value SCT and a register 4 stores a present time (t) of a timer 13. An adder/subtractor 10 outputs a seek amount SK from the TRK1 and the present track position TRK2, a converter 11 outputs a sheek time t3 and a converter 12 outputs a time T1 from the SCT. An adder/subtractor 16 calculates times t1, t2, T2=T1-t3-t1+t2, a phase difference calculator 19 obtains a phase difference time T3, a converter 20 obtains a lead/lag time t4 of a motor 31, a comparator 24 compares its absolute value and the t3, the smaller value is selected (23), the result is outputted as a signal t5, compared (26) with a t7 (=t-t1) to obtain an acceleration/deceleration switching signal S4. |
