Hard disk, control unit for a disk device, and method for controlling a disk device

A control unit for a disk device configured such that a disk write operation or a disk read operation is conducted for data sectors comprising a starting data sector indicated at an intended track of a hard disk after seek control and position-determining control is conducted based on servo data recorded in said hard disk to move a head onto said intended track, comprising:

• a defective user sector-detecting unit for checking a defective user sector on said intended track during said seek control and said position-determining control;
• and
• an alternative processing unit for conducting an alternative operation per servo sector comprising a servo area and a data area provided subsequent to the servo area and having a defect of the defective user sector, when the defective user sector is detected.

A method for controlling a disk device which is configured such that a disk write operation or a disk read operation is conducted for data sectors comprising a starting data sector indicated at an intended track of a hard disk after seek control and position-determining control is conducted based on servo data recorded in said hard disk to move a head onto said intended track, comprising:

• detecting a defective user sector on said intended track during said seek control and said position-determining control during said seek control and said position-determining control;
• and
• conducting an alternative operation per servo sector comprising a servo area and a data area provided subsequent to said servo area and having a defect of said defective user sector, when the defective user sector is detected.