Control device and storage device

• US 7,477,466 B2
• Filed: 10/30/2006
• Issued: 01/13/2009
• Est. Priority Date: 06/15/2006
• Status: Expired due to Fees

• Current Assignee: Toshiba Storage Device Corp (Toshiba Corporation)
• Original Assignee: Fujitsu Limited
• Inventors: Aoki, Shunsuke, Yoshida, Osamu, Yanagi, Shigenori
• Primary Examiner(s): Tzeng; Fred
• Application Number:
  US11/589,401
• Publication Number:
  US 20070291389A1
• Time in Patent Office: 806 Days
• Field of Search: 360/31, 360/75, 360/46
• US Class Current: 360/31
• CPC Class Codes: G11B 20/10009 Improvement or modification of read or write signals
• CPC Class Codes: G11B 20/10027 adjusting the signal strength during recording or reproduction, e.g. variable gain amplifiers optimum power control for optical discs G11B7/125
• CPC Class Codes: G11B 20/10481 optimisation methods
• CPC Class Codes: G11B 2220/2516 Hard disks
• CPC Class Codes: G11B 5/40 Protective measures on heads, e.g. against excessive temperature G11B5/31 takes precedence; protection against wear G11B5/255 ; protective structure of the head: see under structures, e.g. G11B5/3106
• CPC Class Codes: G11B 5/5526 Control therefor; circuits, track configurations or relative disposition of servo-information transducers and servo-information tracks for control thereof G11B5/556 takes precedence
• CPC Class Codes: G11B 5/6029 Measurement using values derived from the data signal read from the disk

Abstract

A control device that controls a storage device having an auto-gain-control function for controlling strength of an output signal from a head that reads data from a storage medium, which includes a determining unit that determines whether the strength of the output signal controlled by the auto-gain-control function is within a predetermined range, an abnormal-float detecting unit that detects an abnormal float of the head based on a result from the determining unit, an abnormal-float-number counting unit that counts a number of times of the detected abnormal floats of the head, and an abnormal-float-count storing unit that stores the counted number of times of the abnormal floats into a storage area of the storage device.

Claims

1. A control device that controls a storage device having an auto-gain-control function for controlling strength of an output signal from a head that reads data from a storage medium, the control device comprising:

a determining unit that determines whether the strength of the output signal controlled by the auto-gain-control function is within a predetermined range;

a detecting unit that detects an abnormal float of the head based on a determination made by the determining unit;

a counting unit that counts a number of times the detecting unit detects abnormal float of the head; and

a storing unit that stores the number of times of the abnormal floats counted by the counting unit into a storage area of the storage device.

2. The control device according to claim 1, wherein the detecting unit detects the abnormal float of the head for each of zones on the storage medium.

3. The control device according to claim 1, wherein the detecting unit detects the abnormal float of the head with respect to each predetermined time-period-section and records a plurality of pieces of data of each detection status corresponding to each time-period-section.

4. The control device according to claim 1, wherein the detecting unit detects the abnormal float of the head at all times.

5. The control device according to claim 1, wherein the detecting unit detects the abnormal float of the head regularly.

6. The control device according to claim 1, further comprising:

a shock detecting unit that detects a shock applied to the storage device from an external source; and

a shock-number counting unit that counts a number of times the shock detecting unit detects shock to the storage device, wherein

the storing unit stores a value obtained by subtracting the number of times of the shocks counted by the shock-number counting unit from the number of times of the abnormal floats counted by the counting unit into the storage area.

7. The control device according to claim 1, further comprising a failure determining unit that determines a possibility of an occurrence of a failure of the head based on the number of times of the abnormal floats of the head counted by the counting unit.

8. The control device according to claim 7, wherein the failure determining unit determines the possibility of an occurrence of a failure based on data of detection of the abnormal floats of the head recorded in a chronological sequence.

9. The control device according to claim 7, further comprising an alert sending unit that sends an alert to a higher-level device when the failure determining unit determines that there is a possibility of an occurrence of a failure of the head.

10. A storage device having an auto-gain-control function for controlling strength of an output signal from a head that reads data from a storage medium, the storage device comprising:

a determining unit that determines whether the strength of the output signal controlled by the auto-gain-control function is within a predetermined range;

a detecting unit that detects an abnormal float of the head based on determination made by the determining unit;

a counting unit that counts a number of times the detecting unit detects abnormal float of the head; and

a storing unit that stores therein the number of times of the abnormal floats counted by the counting unit into a storage area of the storage device.

11. The storage device according to claim 10, wherein the detecting unit detects the abnormal float of the head for each of zones on the storage medium.

12. The storage device according to claim 10, wherein the detecting unit detects the abnormal float of the head with respect to each predetermined time-period-section and records a plurality of pieces of data of each detection status corresponding to each time-period-section.

13. The storage device according to claim 10, wherein the detecting unit detects the abnormal float of the head at all times.

14. The storage device according to claim 10, wherein the detecting unit detects the abnormal float of the head regularly.

15. The storage device according to claim 10, further comprising:

a shock detecting unit that detects a shock applied to the storage device from an external source; and

a shock-number counting unit that counts a number of times the shock detecting unit detects shock to the storage device, wherein

the storing unit stores a value obtained by subtracting the number of times of the shocks counted by the shock-number counting unit from the number of times of the abnormal floats counted by the counting unit of the storage area.

16. The storage device according to claim 10, further comprising a failure determining unit that determines a possibility of an occurrence of a failure of the head based on the number of times of the abnormal floats of the head counted by the counting unit.

17. The storage device according to claim 16, wherein the failure determining unit determines the possibility of an occurrence of a failure based on data of detection of the abnormal floats of the head recorded in a chronological sequence.

18. The storage device according to claim 16, further comprising an alert sending unit that sends an alert to a higher-level device when the failure determining unit determines that there is a possibility of an occurrence of a failure of the head.

19. A control method for controlling a storage device having an auto-gain-control function for controlling strength of an output signal from a head that reads data from a storage medium, the control method comprising:

determining whether the strength of the output signal controlled by the auto-gain-control function is within a predetermined range;

detecting an abnormal float of the head based on a determination made at the determining;

counting a number of times of the abnormal floats of the head detected at the detecting; and

storing the number of times of the abnormal floats counted at the counting into a storage area of the storage device.