Medium drive and method of generating a defect map for registering positions of defects on a medium

摘要

A hard disk drive (HDD) according to an embodiment of the present invention uses three primary defect map (PDM) formats: a single-sector entry format; a multi-sector entry format; and a two-dimensional sector entry format. Methods of registering defective sectors in each such format are illustrated. Defects can be appropriately registered in a limited RAM capacity by selecting an appropriate format according to states of the defects on a magnetic disk.