摘要 |
A zoned sequential track format is shown and described which reduces the number of head switches during disk drive read/write operations. A band of selected tracks that form a data recording zone or a portion of such a zone are organized into an odd number of track sequences with each sequence being resident on a single disk surface. In the embodiment of a drive with an even number of data surfaces, the tracks within the band on one surface are partitioned to form two track sequences. This can readily be accomplished using 2-cylinder skipping to have each sequence contain alternate tracks across the band. By having each track sequence accessed during a generally radial passage of the transducer over the band, the odd number of track sequences causes the transducers to be adjacent the next successive band when the last track sequence of the current band has been accessed. Incrementing between bands is effected by an access between tracks on the same data surface. Similarly, in devices that sequentially access the tracks within a cylinder of tracks, the disk data surfaces are accessed in reverse order during alternate cylinder accesses. This enables incrementing between cylinders with only a one track seek and no head switch.
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