Patent ID: 7177105

Claim:
An apparatus for writing data to and reading data from sectors on a rotating disk in a disk storage device, the apparatus comprising: a timing apparatus for determining the period of time between two adjacent sectors, wherein the period of time between two adjacent sectors relates to phase rotation; a phase-locked loop, responsive to a reference frequency for providing an output clock signal; a first interpolator for adjusting the output clock signal responsive to the period of time between two adjacent sectors; a second interpolator for adjusting the output clock signal responsive to a pre-compensation adjustment; and a mode control, connected to the first and second interpolators, for selecting between a read mode and a write mode; wherein, in write mode, the second interpolator provides a modified output clock signal for synchronously writing data to the rotating disk; and wherein, in read mode, the first interpolator provides a modified output clock signal for reading data from the rotating disk.