Reading/reproducing apparatus having retry arrangement upon failed reading/writing of a signal

• US 6,442,117 B1
• Filed: 06/07/1995
• Issued: 08/27/2002
• Est. Priority Date: 07/11/1991
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Mizokami, Takuya, Matsunami, Naoto, Kaku, Toshimitsu, Saiki, Eisaku
• Primary Examiner(s): Young, W. R.
• Application Number:
  US08/474,137
• Time in Patent Office: 2,638 Days
• Field of Search: 369/32, 369/44-5-, 369/44.29, 369/44-1-, 369/44.39, 369/47-50, 369/54, 369/58, 369/124, 369/59, 369/53, 369/47.3, 369/47.44, 369/53.36, 369/59.11, 369/59.2, 369/124--12, 369/30-1-, 360/26, 360/31, 360/51, 360/53, 360/73.03, 360/77-2-
• US Class Current: 369/47.3
• CPC Class Codes: G11B 19/02 Control of operating function, e.g. switching from recording to reproducing
• CPC Class Codes: G11B 20/10 Digital recording or reproducing
• CPC Class Codes: G11B 20/1403 characterised by the use of two levels
• CPC Class Codes: G11B 20/18 Error detection or correction; Testing , e.g. of drop-outs
• CPC Class Codes: G11B 7/005 Reproducing G11B7/0065 takes precedence

Abstract

A reproducing apparatus including a reading apparatus for reading signals recorded on a recording medium, a reproducing apparatus for reproducing data from read-out signals from the reading apparatus, an error detector for detecting an error in the data reproduced by the reproducing apparatus, a phase-synchronizing apparatus for synchronizing signals, for the reproducing apparatus, a characteristic changing apparatus for changing reproduction characteristics of the reproducing apparatus of loop characteristics of the phase-synchronizing apparatus, when the error detector detects an error on any one of a track on the recording medium, and a retry apparatus for retrying reading of a track on which the error is detected, under changed reproduction characteristics.

Claims

1. A reproducing apparatus comprising:

a reading means for reading signals recorded on a recording medium;

a reproducing means for reproducing data from read-out signals from said reading means;

a phase-synchronizing means for synchronizing signals, for said reproducing means;

an error detector for detecting an error in the data reproduced by said reproducing means;

a retry means for retrying reading of a track on which an error is detected, when said error is detected by said error detector, said track being any track on said recording medium;

a rotating speed changing means for changing a rotating speed of said recording medium to a lower speed, when said error detector still detects any error through said retrying; and

a characteristic changing means for changing reproduction characteristics of said reproducing means of loop characteristics of said phase-synchronizing means, when said error detector still detects any error through said retrying;

wherein, said reading means then reads signals recorded on said recording medium at said lower speed under changed said reproduction characteristics.

2. A reproducing apparatus according to claim 1, wherein said characteristic changing means further comprises:

reducing means for reducing a loop-gain of said phase-synchronizing means when an error in the reproduced data is detected.

3. A reproducing apparatus according to claim 1, wherein:

said phase-synchronizing means further comprises;

a selecting means for selecting one of a plurality of different attenuation ratios related to a loop-gain of said phase-synchronizing means; and

selecting means for selecting one of the different attenuation ratios, which is higher than a value of an attenuation ratio given when said error occurred, when an error in the reproduced data is detected.

4. A reproducing apparatus according to claim 1, further comprising:

a positioning means for changing a positioning of said reading means for reading signals on a specified track on said recording medium, when said error detector detects said error; and

wherein said retry means retrys reading of a track on which said error is detected, under a changed positioning effected by said positioning means.

5. A reproducing apparatus comprising:

a reading means for reading signals recorded on a recording medium;

a reproducing means for reproducing data from read-out signals from said reading means;

an error detector for detecting an error in the data reproduced by said reproducing means;

a retry means for retrying reading of a track, when said reading means fails to read signals on said track, or when said reproducing means fails to reproduce signals on said track, said track being any track on said recording medium;

a rotating speed changing means for changing a rotating speed of said recording medium to a lower speed when said reading means still fails to read signals, or when said reproducing means still fails to reproduce signals, through said retrying of said retry means; and

wherein, said reading means then reads signals recorded on said recording medium at the changed lower speed, and said reproducing means reproduces the signals read-out at the lower speed.

6. A reproducing apparatus according to claim 5, further comprising:

a positioning means for changing a positioning of said reading means for reading signals on a specified track on said recording medium, when said error detector detects said error; and

wherein said retry means retrys reading of a track on which said error is detected, under a changed positioning effected by said positioning means.

7. A reproducing apparatus according to claim 6, further comprising:

a characteristic changing means, for changing reproduction characteristics of said reproducing means in correspondence with a change of bit rates of the reproduced data and with a change of band width, which are caused by said lower rotating speed.

8. A reproducing apparatus according to claim 7, wherein, said characteristic changing means further comprises;

a changing means for changing at least one of equalizing characteristics, filtering characteristics and slice level characteristics.

9. A reproducing apparatus according to claim 8, further comprising:

phase-synchronizing means; and

said characteristic changing means comprising means for changing loop characteristics of said phase synchronizing means.

10. A reproducing apparatus according to claim 7, further comprising:

a phase-synchronizing means; and

said characteristic changing means comprising means for changing loop characteristics of said phase-synchronizing means.

11. A reproducing apparatus according to claim 10, wherein, said characteristic changing means further comprises:

reducing means for reducing a loop-gain of said phase-synchronizing means when an error in the reproduced data is detected.

12. A reproducing apparatus according to claim 10, wherein, said phase-synchronizing means further comprises:

a selecting means for selecting one of a plurality of different attenuation ratios related to said loop-gain of said phase-synchronizing means; and

means for selecting one of the different attenuation ratios, which is higher than a value of an attenuation ratio given when said error occurred, when an error in the reproduced data is detected.

13. A reproducing apparatus comprising:

a reading means for reading signals recorded on a recording medium;

a reproducing means for reproducing data from read-out signals from said reading means;

an error detector for detecting an error in the data reproduced by said reproducing means;

a phase-synchronizing means for synchronizing signals, for said reproducing means;

a characteristic changing means for changing reproduction characteristics of said reproducing means of loop characteristics of said phase-synchronizing means, when said error detector detects an error on any one of a track on said recording medium; and

a retry means for retrying reading of a track on which said error is detected, under changed said reproduction characteristics.

14. In a reproducing apparatus having

a reading means for reading signals recorded on a recording medium,

a reproducing means for reproducing data from read-out signals from said reading means, and

an error detector for detecting an error in the data reproduced by said reproducing means;

a reproducing method comprising the steps of;

reading a track on which an error is detected, when said error is detected by said error detector, said track being any track on said recording medium;

changing a rotating speed of said recording medium to a lower speed, when said error detector still detects, on any tracks any error through retrying;

changing reproduction characteristics of said reproducing means by changing loop characteristics of a phase-synchronizing means, when said error detector still detects any error through said retrying;

wherein said reading means then reads signals recorded on said recording medium at said lower speed under changed said reproduction characteristics.

15. In a reproducing apparatus having

a reading means for reading signals recorded on a recording medium,

a reproducing means for reproducing data from read-out signals from said reading means, and

an error detector for detecting an error in the data reproduced by said reproducing means;

a reproducing method which is applied when said error is detected on any track on said recording medium by said error detector, said method comprising the steps of;

retrying reading of a track, when said reading means fails to read signals on said track, or when said reproducing means fails to reproduce signals on said track, said track being any track on said recording medium;

changing a rotating speed of said recording medium to a lower speed, when said error detector still detects any error through retrying;

retrying a reading and reproducing of the track on which said error is detected, at said lower speed, wherein, said reading means then reads signals recorded on said recording medium at the changed lower speed, and said reproducing means reproduces the signals read-out at the lower speed.

16. In a reproducing apparatus having

a reading means for reading signals recorded on a recording medium,

a reproducing means for reproducing data from read-out signals from said reading means,

an error detector for detecting an error in the data reproduced by said reproducing means;

a phase-synchronizing means for synchronizing signals, for said reproducing means;

a reproducing method comprising the steps of;

changing reproduction characteristics of said reproducing means by changing loop characteristics of said phase-synchronizing means, when said error detector detects an error on any one of a track on said recording medium; and

retrying a reading of a track on which said error is detected, under changed said reproduction characteristics.

17. A reproducing apparatus, comprising:

a reading means for reading signals recorded on a recording medium;

a reproducing means for reproducing data from read-out signals from said reading means;

a retry means for retrying reading of a track, when said reading means fails to read signals on said track, or when said reproducing means fails to reproduce signals on said track, said track being any track on said recording medium;

a rotating speed changing means for changing a rotating speed of said recording medium to a lower speed, when said reading means still fails to read signals, or when said reproducing means still fails to reproduce signals, through said retrying of said retrying means; and

wherein, said reading means then reads signals recorded on said recording medium at the changed lower speed, and said reproducing means reproduces the signals read out at the lower speed.

18. A reproducing apparatus according to claim 17, further comprising:

a characteristic changing means for changing reproduction characteristics of said reproducing means in correspondence with said changed lower speed.

19. A reproducing apparatus according to claim 17, further comprising:

a positioning means for changing a positioning of said reading means for reading signals on the retrying track, when said reading means fails to read signals on said track, or when said reproducing means fails to reproduce signals o n said track;

a phase-synchronizing means; and

a characteristic changing means including means for changing reproduction characteristics of said reproducing means in correspondence with a change of bit rates of the reproduced data and with a change of bandwidth which are caused by said changed lower speed, and further including means for changing loop characteristics of said phase-synchronizing means;

wherein, said retry means retries reading of said retrying track under the positioning changed by said positioning means.

20. A reproducing apparatus according to claim 19, wherein said characteristic changing means further comprises:

a reducing means for reducing a loop gain of said phase-synchronizing means, when said reading means fails to read signals on said track, or when said reproducing means fails to reproduce signals on said track.

21. A reproducing apparatus according to claim 19, wherein said phase-synchronizing means further comprises:

a selecting means for selecting one of a plurality of different attenuation ratios related to said loop gain of said phase-synchronizing means; and

means for selecting one of the different attenuation ratios, which is higer than a value of an attenuation ratio given, when said reading means fails to read signals on said track, or when said reproducing means fails to reproduce signals on said track.