Patent ID: 6735031
Filing Date: 2004-05-11
Classification: G11B

Abstract:
A method for writing timing marks on a rotatable storage medium comprising the steps of:calculating a time delay as a function of at least one of the following: (a) at least one measured time interval between at least one pair of timing marks, the at least one time interval being measured during at least one previous rotation of the rotatable storage medium followed by writing of at least one timing mark at at least two different radial locations; (b) a plurality of measured time intervals between a plurality of pairs of timing marks, the plurality of measured time intervals being measured during a plurality of previous rotations of the rotatable storage medium; (c) a plurality of measured time intervals between a plurality of different pairs of timing marks, the plurality of measured time intervals being measured during a plurality of different previous rotations of the rotatable storage medium; (d) a plurality of measured time intervals between a plurality of different pairs of timing marks, the plurality of measured time intervals being measured during a plurality of different previous radial rotations of the rotatable storage medium; and (e) a weighted average of a plurality of measured time intervals between a plurality of pairs of timing marks, the plurality of measured time intervals being measured during a plurality of previous rotations of the rotatable storage medium; storing a representation of the calculated time delay; during rotation of a rotatable storage medium, detecting at least a portion of a trigger timing mark; and during further rotation of the rotatable storage medium, writing a new timing mark at a location selected based at least in part on the calculated time delay after the detected trigger timing mark.