Patent ID: 7848047

Claim:
A magnetic recording disk drive comprising: a rotatable magnetic recording disk having a plurality of generally circular data tracks and a plurality of angularly spaced synchronization marks extending generally radially across the data tracks, each data track patterned into discrete magnetizable data blocks, wherein the pattern of data blocks in a plurality of the data tracks is circumferentially misaligned; a controller for selecting a data track where data is to be written; a write head for writing data to a selected data track by generating write pulses to magnetize the data blocks in said selected data track; a write clock coupled to the write head for controlling the write pulses to the data blocks; a read head for sensing the synchronization marks; synchronization mark detection circuitry coupled to the read head for controlling the write clock; and phase adjustment circuitry responsive to the selected data track for adjusting the phase of the write clock to thereby correct for circumferential misalignment of the pattern of data blocks in said selected data track.