JPH09320204A - Disk-like recording medium and disk recording/ reproducing device using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To verify in addition a DMA area, to record defect information at that time and to calculate its recording amount, etc., from the probability theory. SOLUTION: This recording medium is divided into a data area 2A recording/ reproducing the data and data management areas (DMA areas) 2B, 2C, managing a defect sector in the data area, and the DMA areas is constituted of DMA recording areas 20A, 22A, recording defect sector information for the data area, a DMA alternation areas 20B, 22B for the defect sector of the recording area itself and DMA management areas 20C, 22C, managing the defect sector in the DMA area. Although alternate sectors recorded on the alternate areas are recorded, respectively on the DMA management areas, in addition to the managing defect area in the data management areas, the recording amount and area occupancy amount, etc., are decided, based on a condition led by a Poisson distribution. Thus, the area is decided efficiently, and even if defect sectors exist, the data are surely read, and reliability is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc-shaped recording medium and a disc recording / reproducing device using the same. Specifically, when a rewritable disc-shaped recording medium has a defective sector, when recording information on this defective sector in the data management area of the same disc-shaped recording medium, it is guided by the probability theory according to the defect of the recording medium. By recording the amount of management information to be recorded in the data management area and the replacement area occupancy for the defective sector information in the data management area based on the conditions described above, information can be recorded while effectively avoiding defective sectors. It is designed so that reproduction can be realized.

[0002]

2. Description of the Related Art In a rewritable disc such as a magneto-optical disc, data is recorded / reproduced in units of sectors provided in a spiral track. Physical addresses (pits) are assigned to each sector by using injection molding or 2P process at the time of making a disc.

The disk is defective due to a defect such as a substrate scratch at the time of molding the disk or a pinhole in the recording film.
Exists. Data cannot be correctly recorded / reproduced in the sector including this defect. Therefore, before using (before shipping) the disc, a defective sector (defective sector) containing a defect existing in the disc is detected, and an address (separately assigned) is assigned so as not to access the defective sector when recording / reproducing data. A sector is specified by a logical address).

The process of allocating a physical address while avoiding such defective sectors is called a defect avoiding process, and this defect management process includes management data (disk structure management table) of sectors and tracks for registering defect information. DD
S: Data Description Structure) is a defect management area for recording information such as defective sectors, that is, a data management area (DMA: Defect Management Area (hereinafter DM).
This is a process of recording (registering) in area A). DD
The defect management data including S data will be referred to as DMA data hereinafter, and the structure thereof is such that the DDS, the primary defect management table, and the secondary defect management table are arranged in this order as shown in JIS X6271-1991. It is prescribed.

When a disc is used, the DMA data recorded in the DMA area is read immediately after the disc is loaded, and recording / reproduction is performed while avoiding a defective sector while referring to the DMA data, thereby preventing the occurrence of a data error, and thus the data Improves reliability.

[0006]

By the way, this DMA
Since the data is read only after loading the disc, the defect information of the disc cannot be known in advance by the recording / reproducing apparatus. Since only the data area is verified and the defective sector is registered, even if the DMA area itself has a defective sector,
No defect avoidance processing is performed on this portion. Therefore, the DMA data may not be reproduced correctly.

The DMA areas are provided on the inner circumference side and the outer circumference side of the disc, respectively, and the same DMA data is recorded in two places each. According to the regulations, each DMA area is composed of 3 tracks, and the track pitch is 1.6 μm. In the case of such a track pitch, when there is a defect with a size of about 4 μm, at most two sectors in the radial direction may be defective, and defect management cannot be performed unless it is supplemented with other DMA data. I will end up.

There is also a method of increasing and recording the DMA data, but even if it is doubled, the probability of being defective in the entire DMA is halved, but the usable range of the DMA area is halved and the individual DMA area is also reduced. It is hard to say that it is an efficient solution because the defect of itself does not change. As the number of DMA data is increased, the number of times the DMA data is read increases accordingly.
Since it takes a long time to access the data after the disk loading, high speed access cannot be expected. AV servers and the like require high-speed access, and are not suitable for such devices.

Therefore, the present invention has solved such a conventional problem, and also verifies the inside of the DMA area.
The management information obtained at that time is recorded in the management area in an overlapping manner with the amount of information derived from the probability theory, thereby performing DMA.
The defect management of the DMA area can be surely performed without increasing the data.

[0010]

In order to solve the above-mentioned problems, a disk-shaped recording medium according to the present invention described in claim 1 manages a data area for recording / reproducing data and a defective sector of this data area. The data management area is divided into a data management area and a defect information recording area for recording the defective sector information for the data area,
The defect information recording area itself is composed of a replacement area for the defective sector, and an auxiliary management area for managing the defective sector itself in the defect information recording area. other,
It is characterized in that each of the replacement sectors recorded in the replacement area is recorded.

According to a second aspect of the present invention, there is provided a disk recording / reproducing apparatus having a data area for recording / reproducing data and a data management area for managing a defective sector of this data area. A defect information recording area for recording the defective sector for the data area, a replacement area for the defective sector of the recording area itself, and an auxiliary management area for managing the defective sector itself in the data management area. In the management area, in addition to the defective sectors in the data management area, a disk-shaped recording medium in which replacement sectors to be recorded in the replacement area are respectively recorded is used, and is recorded in the auxiliary management area. The feature is that data is recorded and reproduced while referring to the management information and avoiding defective sectors. To.

In the present invention, the verification for checking the presence / absence of a defective sector is performed also in the DMA area (data management area), and the verification result information is registered in the same area. Therefore, the DMA area relates to a recording area of DMA data (defective sector information for data area), a replacement area (DMA replacement area) for a defective sector (defective sector for recording management) existing in this recording area, and a defective sector for management. It is divided into a management area (DMA management area).

The number of tracks constituting the DMA management area is derived from the probability theory based on the number of used sectors of the disk and the predicted defective sectors. Considering that the DMA management area also has a defect, the same information is registered a certain number of times as information regarding the defective sector for management. The DMA replacement area is also provided apart from the DMA recording area by a specific number of tracks in consideration of the size of the defective portion.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Next, one embodiment of a disc-shaped recording medium and a disc recording / reproducing apparatus using the same according to the present invention will be described in detail with reference to the drawings. The rewritable disc used is a magneto-optical disc MO.
Is exemplified.

In the disc-shaped recording medium (hereinafter referred to as a disc) according to the present invention, not only the data area but also the DMA area which is the data management area is verified (cert).
ify) is performed and the verification result is registered in the same DMA area. Therefore, the DMA area is configured as follows. This will be described with reference to FIG.

FIG. 1 shows an example of an area format showing an example of the disk 2. A data area 2A having a predetermined number of tracks is provided in the central area of the disk radius for recording / reproducing data. The data area 2A may be provided with a dedicated replacement area for saving the defective sector.

On both sides of the data area 2A, a DMA area 2B functioning as a management area for the data area,
2C is located. The inside of the inner DMA area 2B is a data-in area, and the outside of the outer DMA area 2C is a data-out area.

As described above, in the present invention, the defective sector is also verified in the DMA areas 2B and 2C, and the result is registered. Therefore, as shown in FIG. 3, the DMA areas 2B and 2C are composed of three areas.

That is, in the DMA areas 2B and 2C, the DMA data itself is recorded in the DMA recording areas 20A and 22A. Then, the DMA recording areas 20A and 22A
DM to be recorded here when a defective sector is found
DMA replacement area 20B in which A data is another area,
22B. In addition, the DMA recording area 20A,
22A is a defective sector, and D at that time
Management data (DMA management data) for managing which sector is the MA replacement sector is recorded in the dedicated DMA management areas 20C and 22C.

Subsequently, these plural areas 20A to 20C
And the relationship between 22A to 22C will be described. DMA
The number of tracks forming the recording areas 20A and 22A is 3 according to the above-mentioned rules. DMA replacement area 2
The number of tracks constituting the 0B, 22B and the DMA management areas 20C, 22C is determined as follows.

Consider now the distribution of defective sectors within one track. The defective rate p of the defective sector d in the total number of sectors Q of the disk is p = d / Q. On the other hand, one track is composed of q sectors, and the probability of R defective sectors included in one track P (R)
Is the Poisson distribution,

[0022]

[Equation 1]

It can be expressed as follows. Therefore,
When the defect rate p is p = 10 ⁻³ , the number of sectors q of one track and the total number of sectors Q of the disk are respectively q = 30 Q = 20000, the probability P of defective sectors occurring in each track P (R) and the number of defective tracks generated by probability in the entire disc are as shown in (Table 1) below.

[0024]

[Table 1]

In Table 1, the probability that four or more defective sectors are generated per track is 1 track or less,
It can be judged that it hardly occurs. Therefore, if the same data is recorded in four or more sectors in one track, the probability that the data becomes unreadable due to a disk defect is almost zero.

Strictly speaking, it is possible that a disk defect will occur over two sectors. Therefore, assuming this case, adjacent sectors may become defective at the same time. If the same data (DMA management data) is recorded, there is no probability that the data will become unreadable due to a disk defect.

The probability P that R defective sectors occur
In contrast to (R), when the number of used tracks of the disc is T, the number of sectors recorded in one track, that is, the number S of sectors recorded as DMA management data is S ≧ R + 1 where P (R) × T < The condition of 1 is satisfied.

From the above, the same data is continuously recorded at least 5 times as the DMA management data. In this example, it is recorded 5 times.

Defective sectors generated in the DMA recording areas 20A and 22A are replaced with dedicated DMA replacement areas 20B and 22.
It is recorded (replacement process) in B by the linear replacement method. The number C to be replaced in this case is obtained as follows. Since it is considered that S defective sectors are generated per track as described above, the DMA recording areas 20A and 22A
Supposing that the number of used tracks is D, and the number of tracks required for S × D sectors is t, the number of sectors SC required for the replacement process is SC ≧ S × (D + t) = 3 tracks S = 5 times, S × D = 5 × 3 = 15 sectors 1 track = 30 sectors, and therefore t = 1. Therefore, the number of sectors required for replacement processing SC
SC = 5 × (3 + 1) = 20, and the number of replacement sectors may be 20 or more. Therefore, it is sufficient to prepare one track as the replacement processing area.

According to an empirical rule, the size of defects that may continuously occur in the disk radial direction is 10 tracks or less (16 μm or less because the track pitch is 1.6 μm in the above example). Mostly.

Therefore, the DMA recording areas 20A, 22
The positions of the DMA replacement areas 20B and 22B with respect to A are
If they are arranged with a size larger than the largest defect size in the disk, it is possible to prevent the same sector from becoming consecutive defects due to one defective portion. From the above, in this example DM
The A replacement areas 20B and 22B are the DMA recording area 20.
It is placed at a position 10 tracks away from A and 22A.

When the areas are arranged so as to satisfy the above conditions, it becomes as shown in FIG. The DMA replacement area is located on the outer circumference side of the DMA recording area, and D, which will be described later, is located on the inner circumference side.
Assuming that the MA management area is located so that the user area 2A has n tracks to N tracks as shown in FIG.
When occupying a track, inner DMA recording area 2
In this example, 0A occupies three tracks (n-11) to (n-13). In the outer recording area 22A, in this example, the track (N + 2)
3 tracks from (N + 4) to (N + 4) are occupied.

Then, one track (n-1) located 10 tracks away from the outer track (n-11) of the DMA recording area 20A becomes the DMA replacement area 20B for the DMA data. Then, the next track (n-14) of the inner track (n-13) is DM
It becomes the A management area 20C.

Also in the outer peripheral side DMA area 2C, a DMA management area 22B is provided in the inner peripheral side track (N + 1), and the following three tracks are the DMA recording area 2
2A, and the track (N + 14) located 10 tracks away from the track (N + 4) is DM
It becomes the DMA replacement area 22C for A data.

When there is a defect in the DMA recording areas 20A and 22A, the corresponding DMA data is sequentially recorded from the first sector of the DMA spare area track.

In the present invention, the linear replacement method of sequentially recording from the first sector in this way is adopted. This is because if the linear replacement method is adopted, data search in that area becomes easy. Therefore, when the DMA replacement areas 20B and 22B to be linearly replaced are also defective, they are recorded in the next available sector.

Description will be made with reference to FIG. In the example shown in the figure, one location is provided in the inner DMA area 2B (m / n of n-12 tracks).
There are two sectors, and there are two areas (track (N +) in the DMA recording area 22A of the outer peripheral DMA area 2C.
It is assumed that there is a defect in (m-1) sector of the same track as the m / 2 sector in 3) and one defect in sector 1 of the DMA replacement area 22B ((N + 4) track). DMA data is transferred to the DMA recording areas 20A, 22
When recording in A, the same data is recorded as far apart as possible. In this example, it is assumed that the same data is recorded at positions separated by 45 sectors.

Considering these conditions, the DMA data (D
MAa) is recorded, the first recorded data D
MAa-0 is recorded as it is in sector 0 of the (n-13) track. The second identical data DMAa-1 is recorded in the m / 2 sector of the (n-12) track 45 sectors apart. However, since this sector is a defective sector, it is linearly replaced with sector 0 of the (n + 1) track, which is a replacement sector. Since the DMA data does not have the information amount exceeding the sector, one sector can accommodate one DMA data.

Since the third identical data DMAa-2 is recorded in a sector having no defect, there is no problem. However, since the fourth sector that records the same data DMAa-3 is a defective sector, it is linearly replaced with sector 0 of the (N + 14) track. Since the (m-1) sector of the (N + 4) track is a defective sector, the DMA to be recorded here is
Data is also saved. At this time, the sector 1 itself of the (N + 4) track to be linearly replaced is also a defective sector, and in this case, it is linearly replaced with the next normal sector, sector 2.

When such a linear permutation is performed, the DMA
D indicating which sector in the recording area is the defective sector and which replacement area sector has been linearly replaced at that time
MA management data (table) is configured as shown in FIG. 5, and is recorded in the corresponding DMA management area 20C or 22C. The recorded DMA management data is a defective sector (track number and sector number) and a replacement sector (track number and sector number) at that time, which is recorded five times in a row in the linear replacement order. Since the amount of this information is so small that it can be recorded in one sector, the DMA management area 2
For 0C and 22C, it is sufficient to secure one track as shown in FIG. Instead of the track number and the sector number, the corresponding physical address can be recorded.

By the way, the above-mentioned verification for the DMA area is performed before verifying the data area, and the verification result is DMA management data as the DMA management areas 20C, 22.
Recorded in C. Then verify the data area and DMA
Data is created, and this DMA data is DM while referring to the DMA management data, that is, avoiding defective sectors.
The data is recorded in the A recording areas 20A, 22 or the DMA replacement areas 20B, 22B. 6 and 7 are flowcharts showing the procedure. This flowchart will be described prior to the description of FIG. 1.

FIG. 6 shows an example of recording the DMA management data. As a premise of this, it is assumed that the reference data used for verification is recorded in the DMA areas 2B and 2C. The track is i (i = 1, 2, ...) And the sector is j (j = 0, 1, ...).

When the loading of the disc is completed, the first sector (i, j) = (1,
0) reproduction of reference data and its physical address AD
D is reproduced (step 31).

The address determination condition is that if one of the three same address data precoded in one sector cannot be read, the address is determined to be defective, and the sector is a defective sector, that is, defective. Judge as a sector.

Therefore, when all the address data can be read (step 32), the process proceeds to the determination process regarding the reproduced data as a normal sector (step 3).
3) Regarding the reproduced data, when the reproduced data exceeds the set error correction capability and a data error occurs, or when the synchronous data included in the reproduced data string cannot be detected by a certain number of matching conditions, the sector is determined to be defective. To be done. When these determination conditions are not satisfied, it is determined that the sector has no abnormality.

However, when there is only one address that cannot be read or when the conditions for judging the reproduced data are not cleared, (i, j) at that time is D as a defective sector.
The MA management data is temporarily stored in the memory (step 34).

Then, this verification work is performed for all sectors of all tracks (steps 35 and 36),
D which was saved in the memory when all verification work was completed
The MA management data is DMA management sector 20C or 22.
Recorded in C.

When the verification of the DMA areas 2B and 2C is completed, the verification of the data area 2A is performed according to the procedure of FIG. Also in this case, reference data for verification is recorded in the data area 2A in advance.

First, (i, j) is initialized, and the defective sector is determined from the first sector of the first track based on the reproduction data and the reproduction address (step 41,
42). The above method can be used as the determination method. When it is determined that the sector is defective, the sector information is temporarily stored in the memory as DMA data together with the replacement sector (step 43).

Then, this verification work is carried out for all sectors of all tracks (steps 44, 45),
D which was saved in the memory when all verification work was completed
The MA data is recorded in the DMA recording area or its replacement area while collectively referring to the DMA management data, and therefore, when there is a defective sector, the replacement processing is performed (step 46).

An embodiment of a disc recording / reproducing apparatus 1 for recording / reproducing data and disc verification processing using such a disc will be described with reference to FIG.

In recording / reproducing data in the normal mode, the system controller 3 switches SWl.
To the terminal a side and the switch SW2 to the terminal c side.
The manually input data S1 is given to the ECC encoder 5 as the data S2 via the interface circuit 4 to generate the data S3 to which the ECC is added.

This data S3 is given to the modulator 6 to generate a modulation signal S4 which is modulated into a recording code, and this modulation signal S4 is generated.
Is input to the driver 7 of the laser diode LD via the switch SW2. The output signal S5 of the LD driver 7 is given to the optical pickup 8, and the amount of light emitted from the LD provided inside the optical pickup 8 is modulated and recorded in the data area 2A of the disk 2.

At the same time, the modulation signal S6 generated by the reflected light flux extracted from the optical pickup 8 is amplified by the address head amplifier 9 to generate a modulation signal S7. The modulation signal S7 is output to the address extracting circuit 10 and the address P
The modulation signal S9 given to the LL circuit 11 and extracted only in the address part is input to the address decoder 12. The address data S10 obtained from the address decoder 12 is given to the system controller 3 and monitored to determine in which sector it is recorded.

At the time of data reproduction, the system controller 3 sets the switch SWl to the terminal a side and the switch S.
W2 is switched to the terminal d side. Reproduction power setting circuit 13
The LD driver 7 is driven by the reproduction power corresponding to the control signal S11 output from the optical head 8 and the modulation signal S12 extracted from the optical pickup 8 is amplified by the data head amplifier 14 to generate the modulation signal S13.

The modulated signal S13 is applied to the data extracting circuit 15 and the data PLL circuit 16, and the modulated signal S15 extracted from only the data portion is applied to the ECC decoder 17. The ECC decoder 17 performs error correction, and the error-corrected reproduction data S16 is output to the outside via the switch SW1 and the interface circuit 4.

The ECC decoder 17 further gives an error flag S17 to the system controller 3 to judge whether or not the reproduced data S16 is reproduced correctly.
Further, the address part is judged by the same procedure as that for recording.

In the mode in which the verification process of the disk 2 is performed and the DMA data is recorded in the DMA area 2B or 2C, first, the system controller 3 causes the switch S to switch.
WI is switched to the terminal b side, the verification reference data stored in the RAM 18 is sequentially read out, and the reference data is subjected to a predetermined data process and then the DMA area 2 of the disc 2 is read.
B, 2C and data area 2A are recorded respectively.

After that, the reproduction mode is set, and the reference data and addresses of the DMA areas 2D and 2C are reproduced first. At this time, the system controller 3 follows the procedure of FIG. 6 and sets D for the defective sector and the replacement sector.
After the MA management data is generated and stored in a memory (not shown) provided in association with the system controller 3, all the DMA management data are generated and then collectively.
This is redundantly recorded in the corresponding DMA management areas 20C and 22C.

Thereafter, the data area 2A is reproduced again, this time, the DMA data relating to the defective sector relating to the data area 2A and its replacement sector is generated, and similarly, the DMA recording areas 20A and 22A and the DMA replacement area in some cases are generated. Recorded on 20B and 22B,
The disk verification process ends.

[0061]

As described above, according to the present invention, the DMA area for managing the defective sector of the disk is DM
Verification processing of the defective sector is also performed on the A area itself,
In recording this in the DMA area, the DMA replacement area amount including the recording amount of the DMA management data is calculated based on the condition derived by the probability theory (Poisson distribution).

According to this, D to be recorded in the DMA area
Since the recording amount (number of recordings) of MA management data and the area occupancy can be calculated efficiently, the maximum effect can be exhibited with the minimum area occupancy. Therefore, even if a defective sector occurs, D
It becomes possible to read the MA data with certainty,
The reliability of the disk can be significantly improved as compared with the conventional case.

When a defective sector occurs in the DMA area, the DMA data is replaced by the linear replacement method. Therefore, the access to the replacement sector is very easy, and the DMA management data amount is reduced accordingly and the occupied area of the DMA management area is reduced. You can reduce the number and use the disk efficiently.

Therefore, since the present invention can be expected to increase the access speed, it is extremely suitable to be applied to a rewritable disc such as a magneto-optical disc and a disc recording / reproducing apparatus using the same.

[Brief description of drawings]

FIG. 1 is a system diagram of essential parts showing an embodiment of a disc recording / reproducing apparatus according to the present invention.

FIG. 2 is a plan view showing an embodiment of a disc according to the present invention.

FIG. 3 is a development view showing a physical arrangement relationship on a disc centering on a DMA area.

FIG. 4 DMA when there is a defective sector in the DMA area
It is a figure which shows the positional relationship of a management table.

FIG. 5 is a diagram showing a DMA management table.

FIG. 6 is a flowchart showing an example of DMA area verification processing.

FIG. 7 is a flowchart showing an example of data area verification processing.

[Explanation of symbols]

2 ... disk, 2A ... data area, 2B, 2
C ... DMA area, 20A, 22A ... DMA recording area, 20B, 22B ... DMA replacement area, 2
0C, 22C ... DMA management area, 3 ... System controller

Claims (6)

[Claims] 1. A data area for recording and reproducing data,
This data management area is divided into a data management area for managing defective sectors, and this data management area is a defect information recording area for recording the defective sector information for the data area and a replacement area for the defective sector of the defect information recording area itself. And an auxiliary management area for managing the defective sector itself in the defect information recording area. In this auxiliary management area, in addition to the defective sector in the data management area, a replacement recorded in the replacement area A disk-shaped recording medium, characterized in that each sector is recorded. 2. A data area for recording and reproducing data,
A data management area for managing a defective sector of this data area, the data management area including a defect information recording area for recording the defective sector for the data area, and a replacement area for the defective sector of the recording area itself, It consists of an auxiliary management area that manages the defective sector itself in the data management area, and in this auxiliary management area, in addition to the defective sector in the data management area, replacement sectors recorded in the replacement area, respectively. It is characterized in that a disc-shaped recording medium which is adapted to be recorded is used to refer to the management information recorded in the auxiliary management area so as to perform recording and reproduction of data while avoiding a defective sector. Disk recording / playback device. 3. The data management area is verified prior to verifying the defective sector in the data area, and when the defective sector is found in the data management area, the management defective sector is stored in a memory, and When the information is recorded as management information in the auxiliary management area provided in the data management area after all the data management areas are verified, and then the above data area is verified and a defective sector is found in this data area. Information about the defective sector and its replacement sector is stored in the memory, and after verification of all data areas, this information is recorded in the data management area with reference to the management information recorded in the auxiliary management area. The disk recording / reproducing apparatus according to claim 2, wherein 4. The number of occupied tracks in the auxiliary management area and the number of times of recording the management information are calculated based on a condition derived from the number of sectors of the disk and the number of defective sectors by a probability theory. Claim 2 characterized by the above-mentioned.
Disc recording / reproducing apparatus according to the above. 5. The replacement area in the data management area is provided at a position separated by a predetermined number of tracks so as not to be affected by the recording area for recording the defective sector for data area. 1. The disk-shaped recording medium according to 1. 6. The disc recording / reproducing apparatus according to claim 2, wherein the data area defective sector information is sequentially recorded in the auxiliary management area of the data management area by a linear replacement method.