JPH07302172A - Disk and disk driver - Google Patents

Abstract

PURPOSE:To access each file quickly by recording file management information to a specific address. CONSTITUTION:In a disk (e.g. an optical disk) using a head (e.g. optical head) to record or reproduce data of plural files, file management information used to manage files is recorded to a range at the outer circumference from r1+d and at the inner circumference than r0-d, where (d) is a head seek error, r1 is an innermost track radius of the disk and r0 is an outermost circumferential track radius of the disk. Thus, a long seek operation corresponding to a difference (x1-x0) between an object position x1 and a current radial position x0 is executed. Thus, slowing-down of access to the file management information is prevented and files are quickly recorded or reproduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk and a disk drive device suitable for use in recording or reproducing data on an optical disk.

[0002]

2. Description of the Related Art FIG. 4 shows the structure of the lower surface of a conventional optical disc. As shown in FIG.
The track 2 is formed on the spiral from the inner peripheral side toward the outer peripheral side.

As shown in FIG. 5, such an optical disk 1 is rotated at a predetermined speed by a spindle motor 12, and a predetermined data is recorded on or reproduced from a track 2 by an optical head 11.

An address such as a sector address is recorded at a predetermined position on the track 2, and the optical head 11 can know the current position by reproducing the sector address.

By the way, in order to access any position on the optical disc 1 at high speed, the optical head 11 is sought to a predetermined position (track) in the radial direction of the optical disc 1,
It suffices to wait for the target position (sector) to rotate. To seek the optical head 11 accurately,
Ideally, seek while counting the number of crossing tracks. However, if the optical head 11 is transferred while counting the number of tracks to traverse,
Becomes difficult to transfer at high speed. Therefore, for seeks over a long distance, in order to improve speed, for example, the optical head 1
It is general to seek based on an absolute position represented by the number of steps of a motor 13 including a stepping motor that transfers 1 in the disk radial direction.

However, it is extremely difficult to move the optical head 11 to an accurate position (track) by one seek due to a manufacturing error or thermal deformation of the optical disk 1 or a drive device for driving the optical disk 1. For example, according to the MD (Mini Disc) standard, the track pitch is 1.6 μm.
However, the error is 0.1 μm. The eccentricity is allowed to be 200 μm. Therefore, even if there is no error in the drive device, when seeking for 1000 tracks, about 180 = (0.
A shift of 1 × 1000 + 200) /1.6) lines may occur.

Therefore, in order to access an arbitrary position, a long seek (movement that is not accurate depending on the absolute position but high speed) and a track jump (which is performed while counting the number of crossing tracks, are not fast but accurate) (Movement) is generally combined with.

FIG. 6 shows an example of processing when accessing an arbitrary position. As shown in the figure, first in step S1, the seek target radial position x ₁
, It is determined whether or not it is near the boundary of the track. That is, it is determined whether the target position x ₁ is near the radial position r _i of the innermost track or the radial position r _o of the outermost track.

If the target position x ₁ is not near the boundary, the process proceeds to step S2, where the long seek operation of (x ₁ -x ₀ ) is performed. That is, the long seek operation (movement by the absolute position) corresponding to the difference between the target position x ₁ and the current radial position x ₀ is executed.

Next, in step S3, the sector address X ₀ 'at the current position x ₀ ' after the execution of the long seek operation is read. Furthermore, it progresses to step S4 and step S3.
And read-out 'addresses X _0' of the current position x ₀ in from the difference between the addresses X ₁ target position _{x 1 (X 0 '-X 1} ), the number of tracks to be jump is calculated, on the calculation result Correspondingly, a track jump is performed in step S5. That is, the track jump is performed by the number obtained in step S4 to reach the target address X ₁ .

On the other hand, the target position x for long seek
_{When 1} is in the vicinity of the position r _i of the innermost track or the position r _o of the outermost track, the process proceeds from step S1 to step S6, where ((r _i + d ₀ + d ₁ ) −x ₀ ) (or (r
_{o -d 0 -d 1) -x 0} ) long seek operation is performed. Here, d ₀ and d ₁ represent the error between the current position x ₀ and the target position x ₁ , respectively.

That is, as shown in FIG. 7, the current position x ₀ in the seek operation represented by the step number of the motor 13 has an error of ± d ₀ , and the target position x ₁ is ± d ₁ . There is an error. For example, as a result of executing the long seek operation, the track moves to the inner track from the position r _i of the innermost track, or moves to the track further to the outer track from the position r _{o of the} outermost track. If you do, you will not be able to get the current address. Therefore, in the case of long seek, even if the largest error occurs, it does not move further to the inner circumference side than the innermost circumference track or move further to the outer circumference side than the outermost circumference track. To do so.

After the long seek operation is performed in step S6, the process proceeds to step S3, and the access by the track jump similar to the above case is further performed.

In step S4 described above, the number of tracks to be jumped increases as the target position approaches the innermost track or the outermost track (boundary), and the access distance to the boundary is 2 in the worst case. ×
(D ₀ + d ₁ ).

If RMS (square root of root mean square) of the error at the long seek position with respect to the boundary is ε ″, the following equation holds: ε ″ = ε ′ + d ₀ + d ₁ (1)

Here, ε'is the RMS of the error at the position x ₀ ′ after the long seek, and R of the error at the positions x ₀ and x _1.
When MS is ε ₀ and ε ₁ , respectively, the following equation holds. ε '≦ (ε ₀ + ε ₁ ) <(d ₀ + d ₁ ) (2)

This is because it is obvious that the average value of the error variations is smaller than the maximum value, and since the two error directions are opposite to each other and the probability of canceling each other is 1/2, the position x ₀ ' This is because the variation of the error of is smaller than the sum of the individual variations of the positions x ₀ and x ₁ .

[0018]

In the conventional disk drive, as shown in FIG. 8, the area R ₀ from the position r _i of the innermost track to the position r _o of the outermost track is the data. When it is assumed that the area can be recorded or reproduced, the file management information for managing the file is recorded in the innermost area R ₅₀ including the innermost track.

However, since the access to the vicinity of the innermost track takes time as described above, there is a problem that the operation of accessing an arbitrary file is delayed in the end.

The present invention has been made in view of such a situation, and makes it possible to more quickly access an arbitrary file.

[0021]

A disk according to claim 1 is a disk (for example, the optical disk 1 in FIG. 1) in which a plurality of files are recorded or reproduced by a head (for example, the optical head 11 in FIG. 1). The file management information for managing the
When the radial position of the innermost track of the disc is r _i and the radial position of the outermost track of the disc is r _o , r _i
It is characterized in that the recording is performed in the outer circumference from + d and in the inner circumference from _ro- d.

According to a second aspect of the present invention, there is provided a disk drive device which comprises a recording / reproducing means (for example, the optical head 11 in FIG. 1) for recording or reproducing a file on a disk (for example, the optical disk 1 in FIG. 1) and a recording / reproducing means. The seek means (for example, the servo circuit 32 shown in FIG. 1) for seeking the disk and the file management information for managing the file, the error at the seek time of the recording / reproducing means is d, and the radial position of the innermost track of the disk is r. _i, when the radial position of the outermost track of the disk and r _o, a periphery than r _i + d, r _o
A control means (for example, the control circuit 33 in FIG. 1) for recording or reproducing in an inner range from -d is provided.

Radial position r of the innermost track of the disk
_When the error of _i is d ₁ and the error of the radial position r _o of the outermost track of the disc is d ₀ , the error d is the sum of both (d =
d ₁ + d ₀ ).

The file management information is the radial position r _i.
It can be recorded almost in the center of the + d and r _o -d. Further, the disc can be either an optical disc, a magneto-optical disc, a magnetic disc, or a phase change disc.

[0025]

In the disk according to the first aspect and the disk drive according to the second aspect, the file management information is recorded or reproduced in a range outside the r _i + d and inside the r _o -d. It Therefore, it is possible to prevent the access to the file management information from being delayed, and it is possible to quickly record or reproduce the file.

[0026]

1 is a block diagram showing the configuration of an embodiment of a disk drive device according to the present invention. The optical disc 1 is rotated by a spindle motor 12 so that the linear velocity becomes constant. That is, this optical disc 1
Is a so-called CLV disc (including the case of zone bit recording in which the linear velocity changes for each zone in a predetermined range in the disc radial direction).

The optical head 11, which is moved by the motor 13 in the radial direction of the disk, includes an optical component such as a laser diode inside, and at the time of recording, a recording / reproducing circuit 31.
The optical disc 1 is irradiated with laser light corresponding to the supplied recording data, and at the time of reproduction, the reflected light of the laser light emitted to the optical disc 1 is received to reproduce the information recorded on the optical disc 1. The information reproduced from the optical disc 1 is recorded by the recording / reproducing circuit 3 from the optical head 11.
1 and then output to a circuit (not shown).

The servo circuit 32 generates a sled servo signal, a spindle servo signal, and a tracking servo signal from the signal output from the recording / reproducing circuit 31, and sends the sled servo signal to the motor 13 and the spindle servo signal to the spindle motor 12. In addition, the tracking servo signal is sent to the actuator 34 built in the optical head 11,
It is designed to supply each. For example, the control circuit 33 including a microcomputer monitors the address information output from the recording / reproducing circuit 31 and reads the current position of the optical head 11.

The access processing in the embodiment of FIG. 1 is basically executed in the same manner as the conventional case shown in the flowchart of FIG. Although the description is omitted because it is repeated, as described above, when the target position x ₁ is not near the radial position r _i of the innermost track or the radial position r _o of the outermost track, (x ₁ -
In the case where the long seek operation of (x ₀ ) is performed and it is near the boundary, the long seek of ((r _i + d ₀ + d ₁ ) −x ₀ ) or ((r _o −d ₀ −d ₁ ) −x ₀ ) is performed. The seek is executed.

After executing the long seek operation, the current address X ₀ 'is read, and the number of tracks to be jumped is determined from the difference (X ₀ ' -X ₁ ) between the current address X ₀ 'and the target address X _1. The calculation is performed, and track jumps are performed by the number.

However, in this embodiment, as shown in FIG.
As shown in, the file management information for managing the file, from the radial position r ₂ of the outer circumference from the radial position r _i of the innermost track only _{d 0 + d 1, d 0} + d 1 from the radial position r _o of the outermost track Area R ₁ within the range up to the radial position r _{3 on the} inner circumference only
Recorded in. As a result, when accessing the file management information, step S2 instead of step S6 of FIG.
Since the process of is always executed, quick access is possible.

Furthermore, as shown in FIG. 3, the region R ₁
If the file management information is recorded in the area R ₂ including the radial position r ₄ at the center of the furniture, the file management information is accessed after the file management information is accessed. The average distance between the area where information is recorded and the track where the file is recorded can be shortened, and quicker access becomes possible.

Although the optical disc 1 has a constant linear velocity in the above embodiment, it may have a constant angular velocity (CAV).

The file management information to be recorded may be management information of various file systems other than FAT in MS-DOS (trademark), for example.
Further, the disc can be various discs such as an optical disc, a magneto-optical disc, a magnetic disc, and a phase change disc.

[0035]

As described above, according to the disk of the first aspect and the disk drive apparatus of the second aspect, the file management information is stored on the outer periphery of r _i + d and r _o -d.
Since the data is recorded in the innermost area, the file management information, and therefore each file, can be accessed quickly.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of a disk drive device of the present invention.

FIG. 2 is a diagram illustrating a recording area of file management information in the disc of the present invention.

FIG. 3 is a diagram illustrating another recording area of file management information in the disc of the present invention.

FIG. 4 is a diagram illustrating tracks on an optical disc.

FIG. 5 is a diagram illustrating the principle of recording / reproducing of a conventional optical disc.

FIG. 6 is a diagram illustrating a process of a seek operation.

FIG. 7 is a diagram illustrating a position error during a seek operation.

FIG. 8 is a diagram showing a recording position of a file management area in a conventional disc.

[Explanation of symbols]

 1 optical disk 2 track 11 optical head 12 spindle motor 31 recording / reproducing circuit 32 servo circuit 33 control circuit 34 actuator

[Procedure amendment]

[Submission date] August 17, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

[0026]

1 is a block diagram showing the configuration of an embodiment of a disk drive device according to the present invention. The optical disc 1 is rotated by a spindle motor 12 so that the linear velocity becomes constant. That is, this optical disc 1
Is a so-called CLV disc (in the case of zone bit recording in which the angular velocity changes for each zone within a predetermined range in the radial direction of the disc (the angular velocity is constant within the zone).
However, if the angular velocity of each zone is different )
It is said that.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location G11B 20/00 Z 9294-5D 20/12 9295-5D

Claims (5)

[Claims] 1. A disk in which a plurality of files are recorded or reproduced by a head, file management information for managing the files, error during seek of the head, d, radial position of the innermost track of the disk are recorded. r _i, when the radial position of the track of the outermost circumference of the disc and r _o, a periphery than r _i + d, the disk being characterized in that recorded in the range inner circumference than r _o -d. 2. A recording / reproducing means for recording / reproducing a file to / from a disk, a seek means for causing the recording / reproducing means to seek the disk, and file management information for managing the file, a seek of the recording / reproducing means. when the error d, the radial position of the innermost track of the disk r _i, the radial position of the track of the outermost circumference of the disc and r _o during, a periphery than r _i + d, r _o - A disk drive device, comprising: a control unit for recording in an inner peripheral range of d. 3. When the error of the radial position r _i of the innermost track of the disk is d ₁ and the error of the radial position r _o of the outermost track of the disk is d ₀ , the error d is
The disk or disk drive device according to claim 1 or 2, which is the sum of both. 4. The disk or the disk drive device according to claim 1, wherein the file management information is recorded substantially at the center of the radial positions r _i + d and r _o -d. 5. The disk or disk drive device according to claim 1, wherein the disk is one of an optical disk, a magneto-optical disk, a magnetic disk, and a phase change disk.