Hitachi Global Storage Technologies Netherlands B.v.

Toshiaki Satoh

Masahiro Shimizu

Kyo Akagi

Takashi Kuroda

Takahiro Nakagawa

Hiroshi Fukuyama

Masaki Kudoh

Haruo Andoh

Tomoharu Maeno

Yuhji Yokoe

Embodiments in accordance with the present invention relate to identifying an address of user data to be registered as a defective user data address in disk defect inspection. In an embodiment of the present invention, in the state where a write element is positioned to a target position to execute data write processing to execute normal data read processing, a write element executes data write processing. If a predefined error occurs during the data write processing, an address of user data for which the normal data write processing is executed is estimated using the error-causing servo data as a target. In addition, an address of the servo data used as the target during the normal data write processing for the estimated address of the user data is identified. If the identified address of the servo data and the address of the error-causing servo data match with each other, the estimated address of the user data is registered as a defective user data address.

Recording disk drive and method of managing defective regions in the same

Embodiments of the present invention provide a defect registration method for performing defect registration of sectors on a magnetic disk. In one embodiment, a rectangular detection window is applied to each defect sector. A threshold value of the detection window is set at 2. In addition, an additional sector group is defined for the detection window. The additional sector group is a target of the defect registration if the number of defect sectors exceeds the threshold value. The additional sector group covers sectors that are not judged as defects in defect detection inspection, but that are expected to be potentially defective. Even if the detection window is applied to a defect sector, an additional sector group is not generated. However, if the detection window is applied to a defect sector, an additional sector group is generated. If the detection window is applied to a defect pattern, an additional sector group is generated.

Defect registration method of magnetic disk, and magnetic disk drive

Embodiments in accordance with the present invention erase a desired area on a recording surface of disk or disk drive apparatus. According to an embodiment, a hard disk drive (HDD) performs erase on a recording surface by moving a head element unit at one-half a servo track pitch with reference to a servo address. Before actual erase is started on the recording surface, the HDD generates a management table configured based on servo addresses from a management table configured based on data tracks. At an erase process, the HDD sets parameters in accordance with the zone and skips a management area with reference to this management table based on the servo addresses.

Method for erase process on recording surface of disk and disk drive apparatus

A method for registering a defect map within a hard disk drive is disclosed. A hard disk drive includes a recording disk, a head assembly, and a controller. Multiple sectors are formed on the recording disk, and the head assembly includes a head for reading/writing data from/to the recording disk. The controller, which controls the head assembly to read/write data from/to the recording disk, includes a defect sector positional information holding device and a sector identification device. The defect sector positional information holding device holds positional information of a defect sector disabled to read/write data therefrom/thereto the recording disk. The positional information includes the number of the defect sectors continued in a circumferential direction and in a radial direction of the recording disk. The sector identification device refers to the positional information of the defect sector so as to identify a target sector from/in which data is to be read/written when a read/write command is received from a host computer.

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Kanagawa, Japan

Toshiaki Satoh