Patent ID: 8427772

Claim:
A magnetic recording disk drive comprising: a rotatable magnetic recording disk having a plurality of generally circular data tracks, a plurality of angularly spaced synchronization marks extending generally radially across the data tracks, and a plurality of angularly spaced servo sectors extending generally radially across the data tracks, the data tracks being patterned into discrete circumferentially spaced magnetizable data islands, the data islands being grouped into data regions located between the servo sectors, each data region being grouped into a plurality of data sectors, and wherein the servo sectors contain positioning information and data island misplacement information for the data islands; a controller for selecting the data tracks and data sectors where data is to be written; a write head for writing data to the data sectors by generating write pulses to magnetize the data islands in the data sectors; a write clock coupled to the write head for controlling the write pulses to the data islands; a read head for sensing the synchronization marks and reading the positioning information and data island misplacement information in the servo sectors; an actuator coupled to the read head and write head for moving the write head to the data tracks and maintaining the write head on the data tracks in response to positioning information read by the read head; synchronization mark detection circuitry coupled to the read head for controlling the write clock; and write clock adjustment circuitry responsive to the data island misplacement information read by the read head for adjusting the timing of the write clock pulses to the data islands.