Disk drive and method of controlling the same

• US 20060132959A1
• Filed: 11/28/2005
• Published: 06/22/2006
• Est. Priority Date: 12/21/2004
• Status: Active Grant

• Current Assignee: HGST Netherlands B.V. (Western Digital Corporation)
• Original Assignee: Hitachi Global Storage Technologies Netherlands BV (Western Digital Corporation)
• Inventors: Andoh, Haruo
• Granted Patent: US 7,362,539 B2
• Time in Patent Office: Days
• US Class Current: 360/69
• CPC Class Codes: G11B 5/5547 "Seek" control and circuits therefor G11B5/5556 takes precedence

Abstract

Embodiments of the invention provide a disk drive capable of preventing the deterioration of performance. In one embodiment, a disk drive includes a disk medium; a head capable of performing a read/write operation for accessing the disk medium to read information from and to write information to the disk medium; a head controller for controlling the position of the head so that the head describes a substantially spiral trajectory relative to the disk medium; and a controller capable of controlling the head controller, of performing a read/write operation for reading or writing information with reference to an identifier table associating sector identifiers identifying sectors on a specified track with logical block addresses, and of creating an identifier table for a track to be accessed next during the read/write operation.

Claims

1. A disk drive comprising:

a disk medium;

a head configured to perform a read/write operation for accessing the disk medium to read information from and to write information to the disk medium;

a head controller configured to control the position of the head so that the head describes a substantially spiral trajectory relative to the surface of the disk medium; and

a controller configured to control the head controller, perform a read/write operation for writing or reading information with reference to an identifier table associating sector identifiers identifying sectors on an accessed track with logical block addresses, and create an identifier table for a track to be accessed next during the read/write operation.

2. The disk drive according to claim 1, wherein the controller obtains information about an identifier identifying an accessed sector, and creates an identifier table for a track to be accessed next while an access operation to access the disk medium is being performed when a sector identified by the obtained information is apart from a predetermined reference sector position by a distance longer than a predetermined offset.

3. The disk drive according to claim 2, wherein the controller is configured to create a sector entry related to sectors included in a track to be accessed next and record the sector entry on the identifier table while the access operation to access the disk medium is being performed when the sector identified by the obtained information is apart from the predetermined reference sector by a distance longer than the predetermined offset.

4. The disk drive according to claim 3, wherein the controller performs sequential access by repeatedly:

referring to one of the sector entries on the identifier table and providing an instruction requesting access to a sector in a current track identified by a sector identified in the sector entry;

accessing the sector to read or write information; and

creating a sector entry for a next track and overwriting the sector in the current track with the newly created sector entry when the sector identified by the obtained information is apart from the predetermined reference sector by a distance longer than the predetermined offset.

5. The disk drive according to claim 1 further comprising a storage unit for holding defective sector information specifying defective sectors;

wherein, when the controller creates an identifier table for a track to be accessed next, if the track to be accessed next has a sector identified as a defect sector by the defect sector information, the controller associates information to the effect that the sector identified is defective with a sector identifier identifying the defective sector in the identifier table.

6. A method of controlling a disk drive including a disk medium, and a read/write head capable of accessing the disk medium to carry out a read/write operation, said method comprising:

controlling the position of the read/write head such that the read/write head describes a substantially spiral trajectory relative to the disk medium;

performing a read/write operation to write information to or read information from an accessed track with reference to an identifier table associating identifiers identifying sectors on the track with logical addresses; and

creating an identifier table for a track to be accessed next during the read/write operation.

7. The method of controlling a disk drive according to claim 6, wherein creating the identifier table comprises:

obtaining information about an identifier identifying an accessed sector; and

creating an identifier table for a track to be accessed next while an access operation to access the disk medium is being performed when a sector identified by the obtained information is apart from a predetermined reference sector position by a distance longer than a predetermined offset.

8. The method of controlling disk drive according to claim 7, wherein creating the identifier table for a track to be accessed next comprises:

creating a sector entry related to sectors included in a track to be accessed next and recording the sector entry on the identifier table while the access operation to access the disk medium is being performed when the sector identified by the obtained information is apart from the predetermined reference sector by a distance longer than the predetermined offset.

9. The method of controlling disk drive according to claim 8, further comprising performing sequential access by repeatedly:

referring to one of the sector entries on the identifier table and providing an instruction requesting access to a sector in a current track identified by a sector identified in the sector entry;

accessing the sector to read or write information; and

creating a sector entry for a next track and overwriting the sector in the current track with the newly created sector entry when the sector identified by the obtained information is apart from the predetermined reference sector by a distance longer than the predetermined offset.

10. The method of controlling disk drive according to claim 6,

wherein the disk drive includes a storage unit for holding defective sector information specifying defective sectors;

and

wherein creating an identifier table for a track to be accessed next comprises, if the track to be accessed next has a sector identified as a defect sector by the defect sector information, associating information to the effect that the sector identified is defective with a sector identifier identifying the defective sector in the identifier table.