Patent ID: 7443625

Claim:
A magnetic disk drive including a composite head having a write element for writing magnetic information on a magnetic disk and a read element for converting the magnetic information on the magnetic disk into an electrical signal, comprising: the composite head whose write track width formed by the write element is larger than the track pitch, in which when writing magnetic information onto the magnetic disk, writing is performed by writing each track while shifting the write element's position by a width of the track in the track width direction for every writing; and when reading magnetic information from the magnetic disk, the read element is positioned at the center of the track; and a shift address data table for managing cross references of physical addresses on the magnetic disk, in which when overwriting previously written information, a search is made in the shift address data table, and a pointer value of the sector or track to be overwritten is changed to a value indicating a final pointer pointing to a track to be written to, and new information is written on the sector or the track of the magnetic disk indicated by the final pointer value.