Patent ID: 6654904
Filing Date: 2003-11-25
Classification: G11B

Abstract:
A defect register method for registering in a defect map an address of a defective sector in a data recording medium, which is divided into a plurality of partial regions each of which is divided into a plurality of sectors, comprising the steps of:(A) discriminating a series of defective sectors consisting of a plurality of defective sectors with continuous addresses, the plurality of defective sectors meeting a predetermined condition with respect to a partial region where the defective sectors are located or alternative sectors which correspond to the defective sectors; (B) logically grouping sectors with contiguous addresses that are all within a same partial region and identifying a grouping of said sectors with an address of a first sector within said group and a length of the sectors within said group, wherein said logically grouping excludes sectors not within said partial region; and (C) registering the series of defective sectors in a defect map by registering a first address and sector length of the series of defective sectors, wherein said grouping of said sectors is registered similarly to individual sectors within said defect map such that substantially less storage area is required to register contiguous defective sectors within said defect map and less processing overhead is required to register and access said series of defective sectors of said data recording medium.