Magnetic disk device and servo gate generation method
AssigneesKabushiki Kaisha Toshiba, Toshiba Electronic Devices & Storage Corporation
InventorNaoki Tagami
Life of this patent
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Abstract
According to one embodiment, a magnetic disk device includes a disk including a servo sector including burst data, a head including a write head which writes data to the disk, and a read head which reads data from the disk, and a controller which generates a first normal servo gate for applying servo read to the servo sector, wherein when a short servo gate for at least applying servo read to the burst data is generated, the controller generates the short servo gate and the first normal servo gate, and when the short servo gate is not generated, the controller generates the first normal servo gate and a second normal servo gate different from the first normal servo gate.
Claims20
A magnetic disk device comprising:
- a disk comprising a first track comprising a first servo sector and a second servo sector which is positioned after the first servo sector and is different from the first servo sector;
- a head comprising a write head which writes data to the disk, and a read head which reads data from the disk;
- and
- a controller which generates a first normal servo gate for applying servo read to the first servo sector in its entirety
- and generates a short servo gate for applying servo read to a part of the second servo sector based on servo data obtained by the servo read from the first servo sector, and
- when the controller does not generate the short servo gate, the controller generates a second normal servo gate different from the first normal servo gate for applying servo read to the second servo sector in its entirety.
A magnetic disk device comprising:
- a disk a first track comprising a first servo sector and a second servo sector which is positioned after the first servo sector and is different from the first servo sector;
- a head comprising a write head which writes data to the disk, and a read head which reads data from the disk, and
- a controller which generates a first normal servo gate having a first length of time of assertion and negation for applying servo read to the first servo sector in its entirety, generates a short servo gate having a second length of time of assertion and negation for applying servo read to a part of the second servo sector, and generates a second normal servo gate having a third length of time of assertion and negation for applying servo read to the second servo sector in its entirety, wherein
- the second length is less than the first length and the third length, and
- the third length is different from the first length and is greater than the second length.
A servo gate generation method applied to a magnetic disk device comprising:
- a disk comprising a first track comprising a first servo sector and a second servo sector which is positioned after the first servo sector and is different from the first servo sector;
- and a head comprising a write head which writes data to the disk, and a read head which reads data from the disk,
- the method comprising:
- generating a first normal servo gate for applying servo read to the first servo sector in its entirety;
- generating a short servo gate for applying servo read to a part of the second servo sector based on servo data obtained by the servo read from the first servo sector;
- and
- when not generating the short servo gate, generating a second normal servo gate different from the first normal servo gate for applying servo read to the second servo sector in its entirety.
Dependencies are inferred from the claim text.