| 摘要 |
<p>A system and method of positioning the head in a memory wherein a control circuit such as a microprocessor unit that is used for positioning the head is lightened of load while keeping the increase in speed and precision of head positioning, so that higher-speed operation of the head and/or the increase in recording density of the recording medium are attained with the help of a low-price control circuit. The control system has track cross pulse generator means (54, 55, 282, 283) that produces either an odd-number or an even-number track cross pulses (PODD or PEVEN) based upon the positional data that indicates that the head crosses the tracks of the recording medium. The control circuit (22) (a) sets the track cross pulse generator means, before the speed control is started, in such a manner that said track cross pulse generator means produces track cross pulses of an odd number when there are an even number of desired tracks and produces track cross pulses of an odd number when there are an odd number of desired tracks, and then controls the speed of the head-drive actuator so that the head is positioned on a desired track, (b) updates the remainder of track movement (DIFF), when the first track cross pulse is input, depending upon a difference between the track position of the head before the speed control is started and a desired track position, and (c) reduces the remainder of track movement by two tracks every time a track cross pulse is received thereafter. Thus, the track cross pulse generator means sends to the control circuit an odd number or an even number of track cross pulses that indicate a desired track after every two tracks.</p> |
