Method and apparatus for determining track position of a head on a

Abstract

An access controller for a recording medium, said recording medium including a plurality of track blocks, each of which includes a plurality of tracks, including a generating section including a head, for reading out servo patterns recorded on the recording medium, and for generating servo data from the readout servo patterns, the servo patterns being associated with the tracks, a storage section for storing previous position data and movement amount data, the previous block-in position data representing a previous track position of said head in a current track block of the track blocks, and the movement amount data representing a number of tracks between the previous track position and a track position previous to the previous track position, and a determination section for selectively determining in accordance with the servo data current block-in position data from at least one of the servo data generated by the generating section and the previous block-in position data and the movement amount data stored in the storage section.