JP2004281022A - Optical disk device and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means that can record and reproduce data even if address errors are contained due to disk defects. <P>SOLUTION: The optical disk has the address information given to each first recording area set up on the track and records and reproduces the data in the units of second recording areas consisting of a plurality of the first recording areas. The optical disk unit counts the number of the addresses discriminated to be normal in the address information given to each of the plurality of the first recording areas composing the second recording area, and has a control means to perform control of recording and reproducing of the data on the optical disk by comparing the number thus obtained with the predetermined threshold. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an optical disk device that performs recording or reproduction on an optical disk and a control method thereof.
[0002]
[Prior art]
CD (Compact Disk) standards such as a data write-once type (Write Once) CD-R and a rewritable type (ReWritable) CD-RW are one of the standards of an optical disk capable of recording / reproducing using a laser beam. There is. In recent years, the diffusion rate of CD-R and CD-RW discs has been expanding along with the price reduction, and they have been widely used.
[0003]
In an optical disk (CD standard medium) conforming to the physical format of the CD standard capable of recording / reproducing, a pre-groove (guide groove) forming a track is wobbled in accordance with a waveform FM-modulated based on absolute time information or the like. Meandering). By demodulating the wobbling frequency from this pre-groove, an absolute time in pregroove (ATIP) address, which is absolute time information, can be obtained. The ATIP address is used as information for managing a recording / reproducing position of data on the CD standard medium in an optical disc apparatus that records / reproduces data using the logical format of the CD standard. .
[0004]
By the way, the recording capacity of CD-R and CD-RW discs is about 650 Mbytes or 700 Mbytes as standard. In recent years, there has been a high demand for an optical disc medium to have a larger capacity for video recording and the like, and the standard recording capacities of CD-R and CD-RW discs cannot meet such needs.
[0005]
For this reason, an ATIP address is obtained from an existing CD standard medium such as a CD-R and a CD-RW, and a high-density recording address converted based on the obtained ATIP address is used to convert the CD-R medium to a CD standard medium. A mechanism for realizing high-density recording has been proposed (for example, see Patent Document 1 shown below). Note that the high-density recording address is assigned to each of the divided areas (sectors) when a recording area corresponding to a section of two adjacent ATIP addresses is logically divided by a predetermined number (magnification of recording density). Address.
[0006]
An optical disk device having the above-described mechanism (conventional optical disk device) records ID (Identification Data) information associated with a high-density recording address together with actual data in the above-described partitioned area. The object is to convert the above-mentioned ID information optically read from a CD standard medium into an address for high-density recording, and to use the converted address for high-density recording to determine the position of the above-mentioned sectioned area. Is to identify.
[0007]
Further, in a conventional optical disk device, a technique for recording and reproducing data on a CD standard medium based on a logical format conforming to a DVD (Digital Versatile Disk) standard has been proposed. In a logical format conforming to the DVD standard, one ECC (Error Correction Code) block is used as a recording / reproducing unit. Normally, one ECC block of data is recorded in a recording area corresponding to 8 ATIP sections. Become.
[0008]
[Patent Document 1]
JP-A-2002-56617
[0009]
[Problems to be solved by the invention]
By the way, in a conventional optical disk device, as a process before recording / reproducing data from a target track position on a CD standard medium, an optical head is moved in a direction along a track, and a light spot is irradiated on the target track position. A seek operation for positioning at a place is performed. In the process of the seek operation, the optical disc apparatus traces a segmented area (sector) from the seek start position to the seek target position by using a light spot. Then, based on the reflected light of the light spot, the ID information recorded in the segmented area (sector) is read, and by referring to the high-density recording address converted from the ID information, the current light on the track is read. The position of the spot will be identified.
[0010]
However, due to defects in the CD standard medium itself, such as dust and dirt on the CD standard medium, scratches, and eccentricity of the disc, optical information is not normally read from the CD standard medium. The read ID information and the high-density recording address converted from the ID information may be incorrect information. In this case, an incorrect high-density recording address is referred to in the course of the seek operation, so that the positioning accuracy in the seek operation is reduced, and data recording / reproduction from the target track position is not performed normally. The problem occurs.
[0011]
Also, after the seek operation is normally performed, in the process of recording and reproducing data from the target track position, the above-described optical information reading is not performed normally, and during the recording or reproduction of data. An address for high-density recording corresponding to a certain track position becomes incorrect information, and data recording / reproduction may not be performed normally. In particular, when data recording is not performed normally, data is recorded at an undesired track position, and there is a problem that the recording area of the CD standard medium is wasted.
[0012]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem, and has as its object to provide an optical disk device with improved reliability and a control method thereof.
[0013]
[Means for Solving the Problems]
A main aspect of the present invention for solving the above-mentioned problem is that an optical disc having address information assigned to each first recording area set on a track includes a plurality of the first recording areas. In an optical disc device that records or reproduces data on or from the optical disc in units of a second recording area, the address information assigned to each of the plurality of first recording areas constituting the second recording area Among them, there is provided control means for performing control relating to recording or reproduction of data on the optical disc based on the result of comparing the number of the address information identified as normal with a predetermined threshold value.
[0014]
Preferably, as a second aspect according to the present invention, the control means includes the number of the address information identified as normal among the address information included in the second recording area, the threshold value, In contrast to the above, a threshold determining means for determining whether the number of the address information is greater than or less than the threshold is provided.
The “first recording area” is, for example, “1 ATIP section” described later, and the “address information” is, for example, “ATIP address” described later. The “second recording area” is, for example, “1 ECC block” described later. Further, the above-mentioned “control means” is, for example, a “system control microcomputer” described later, and the “threshold determination means” is, for example, a means provided in a “system control microcomputer” described later.
Here, optical information is not normally read from the optical disk due to a defect of the optical disk itself, such as dust on the optical disk, scratches, eccentricity of the disk, etc., and the optical disk is normal (or not normal). There is a possibility that the number of pieces of address information is likely to be larger or smaller than a predetermined threshold.
In the present invention, by taking the above-described mechanism in consideration of such an event, the second recording area that is not normal, that is, the number of normal (or abnormal) address information is greater than or less than a predetermined threshold value. Can be identified. Then, in the control relating to the recording or reproduction of data on the optical disk, the reliability of the optical disk device can be improved by effectively utilizing the above-described mechanism for identifying an abnormal second recording area.
[0015]
As a third aspect according to the present invention, when a seek operation for moving a light spot irradiated on the optical disc from a seek start position to a seek target position is performed, the control unit performs the seek operation from the seek start position. Control for stopping the seek operation is performed for at least one of the second recording areas included up to the target position, based on the determination result of the threshold value determination unit.
The above-mentioned "stop seek operation" means, for example, that the "control means" controls the slide mechanism (not shown) by the optical head servo circuit and the recording data by the encoder for the high-density recording mode. This is to stop encoding processing, decoding processing of reproduced data by a decoder for high-density recording mode, a PLL, or the like.
According to the present invention, by having the above-described mechanism, it is highly likely that an abnormal second recording area is identified during the seek operation, that is, the optical reading from the optical disc is not normally performed. In this case, the seek operation is stopped. This improves the reliability of the seek operation. In particular, in the case of a seek operation before data recording, data is not recorded at an erroneous seek target position, so that it is possible to suppress wasteful consumption of a recording area of the optical disc.
[0016]
As a fourth aspect according to the present invention, when a seek operation for moving a light spot irradiated on the optical disc from a seek start position to a seek target position is performed, the control unit performs the seek operation from the seek start position. For at least one of the second recording areas included up to a target position, control for retrying the seek operation with a predetermined number of times as an upper limit is performed based on a determination result of the threshold value determination unit.
According to the present invention, by having the above-described mechanism, it is highly likely that an abnormal second recording area is identified during the seek operation, that is, the optical reading from the optical disc is not normally performed. In this case, the seek operation is retried. This improves the reliability of the seek operation. In particular, in the case of a seek operation before data recording, data is not recorded at an erroneous seek target position, so that it is possible to suppress wasteful consumption of a recording area of the optical disc.
[0017]
As a fifth aspect according to the present invention, the control unit performs the second recording on the second recording area in a state where data is being recorded or reproduced based on a result of the determination by the threshold value determining unit. Control for stopping recording or reproduction of data in the area is performed.
The "stop of the data recording / reproducing process" means, for example, that the "control means" controls the slide mechanism (not shown) by the optical head servo circuit and the encoder for the high-density recording mode. This is to stop recording data encoding processing, reproduction data decoding processing by a high-density recording mode decoder, PLL, or the like.
According to the present invention, by employing the above-described mechanism, when an abnormal second recording area is identified while data is being recorded or reproduced after a seek operation is completed, that is, optical reading from the optical disc is performed. If there is a high possibility that the data has not been correctly written, the process of recording / reproducing data to / from the optical disc is stopped. This improves the reliability of the data recording / reproducing process. In particular, in the case of data recording processing, it is possible to suppress wasteful consumption of the recording area of the optical disc.
[0018]
As a sixth aspect according to the present invention, the optical disc has the address information and address check information for checking the address information in association with the wobbling information of the track. Receiving the wobbling information read from the optical disc, receiving the wobbling information read from the optical disc, and address generation means for generating the address information corresponding to the received wobbling information; Address information checking means for checking the address information generated by the address generating means based on the address checking information corresponding to the received wobbling information.
The above-mentioned “information for address check” is, for example, “CRC data” to be described later, and the above-mentioned “address generation means” and “address information check means” are, for example, “ATIP decoder” to be described later. ".
[0019]
As a seventh aspect according to the present invention, the control means receives address check result information indicating a check result of the address information from the address information check means, and the received address check result information indicates the checked address. When the information indicates that the information is normal, the information processing apparatus further includes a parameter value updating unit that updates a predetermined parameter value, and the threshold value determining unit compares the updated parameter value with the threshold value, and It is determined whether or not the number of the pieces of address information identified as normal among the pieces of address information included in the recording area is greater than or less than the threshold.
The “parameter value updating unit” described above is, for example, a unit included in a “system control microcomputer” described later.
[0020]
As an eighth aspect according to the present invention, for an optical disc having address information assigned to each first recording area set on a track, an optical disc having a plurality of first recording areas is provided. In a control method of an optical disc apparatus for recording or reproducing data on or from the optical disc in units of two recording areas, the address information assigned to each of the plurality of first recording areas constituting the second recording area Among them, control relating to recording or reproduction of data on the optical disc is performed based on the result of comparing the number of the address information identified as normal with a predetermined threshold.
According to the present invention, the second recording area that is not normal, that is, the second recording area in which the number of normal (or abnormal) address information is greater than or less than a predetermined threshold value by having the above-described mechanism. Can be identified. In the control relating to the recording or reproduction of data on or from the optical disc, the reliability of the control method of the optical disc apparatus can be improved by effectively utilizing the above-described mechanism for identifying an abnormal second recording area. It becomes possible.
Other features of the present invention will be apparent from the accompanying drawings and the description of the present specification.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
=== Example ===
Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.
<System configuration>
First, a schematic configuration of a system including an optical disk device 100 according to an embodiment of the present invention will be described with reference to FIG. Here, the optical disc device 100 shown in FIG. 1 uses an address for high-density recording on an optical disc (CD standard medium) 200 conforming to a physical format of the existing CD standard such as CD-R and CD-RW. Recording and playback are possible. The physical format defines the dimensions of the optical disc 200, a recording / reproducing method, a sector configuration, and the like.
In consideration of user's convenience, it is preferable to support recording / reproduction on a CD standard medium in a standard recording mode conforming to the logical format of the CD standard. Further, the optical disk device 100 is capable of operating the optical disk 200 (DVD standard medium) based on the physical format of the DVD (Digital Versatile Disk) standard such as DVD-ROM, DVD-R, and DVD-RW / + RW. Recording / reproduction in a standard recording mode conforming to the format may be supported. Note that the logical format defines a mechanism of a data structure such as a file, a directory, and a volume.
[0022]
Hereinafter, for convenience of explanation, the optical disc 200 is a CD standard medium. In this CD standard medium, a pre-groove (guide groove) forming a track is wobbling (meandering) in accordance with an FM-modulated waveform based on absolute time information or the like. By demodulating the wobbling frequency from the pre-groove, an absolute time in pregroove (ATIP) address, which is absolute time information, can be obtained.
[0023]
Also, the optical disc apparatus 100 supports only a high-density recording mode using a high-density recording address or the like as a logical format used for recording / reproducing processing on the optical disc (CD standard medium) 200.
[0024]
As shown in FIG. 1, the optical disc apparatus 100 includes an optical head 1, a front end processing unit 2, an optical head servo circuit 3, a WBL detection unit 4, an ATIP decoder ("address generation means", "address information inspection means") 5, PSN decoder 6, PLL circuit 7, high-density recording mode decoder 8, high-density recording mode encoder 9, interface unit 10, RAM 11, system control microcomputer ("control means") 12, laser output control circuit 13, laser drive circuit 14, a spindle motor 15, a motor drive circuit 16, and a motor control circuit 17.
[0025]
The optical head 1 receives an objective lens (not shown), a laser element 1a that emits a laser beam B to the optical disc 200 through the objective lens, and receives reflected light based on a light spot irradiated on the optical disc 200. And a light receiving element (not shown). The optical head 1 has a slide mechanism for performing a seek operation, that is, moving the optical head 1 in a direction along a track and positioning the optical head 1 at a position where a light spot is irradiated on a target track position. A tracking mechanism for performing control (tracking control) for causing the laser beam B emitted to the optical disc 200 to follow a target track to be recorded / reproduced, and control for correcting the defocus of the laser beam B emitted to the optical disc 200 (focus control) ) Is incorporated (both are not shown).
[0026]
The front end processing unit 2 is a tracking error signal based on an RF amplifier including a matrix operation circuit, an amplification circuit, a waveform shaping circuit (equalizer), a three-beam method, a push-pull method, a DPD (Differential Phase Detection) method, or the like. A generation circuit, a focus error signal generation circuit based on an astigmatism method, a Foucault method, and the like are provided (all are not shown).
[0027]
The RF amplifier outputs an RF signal (radio frequency signal) for determining the presence or absence of a pit on a track based on an electric signal generated by a light receiving element (not shown) of the optical head 1 according to the amount of received light. Generate. Note that this RF signal is binarized. Further, the RF signal includes a wobbling frequency component for acquiring an ATIP address. Further, when the optical disc 200 is recorded at a high density in advance, the RF signal includes ID information described later.
[0028]
The tracking error signal generation circuit controls the tracking control mechanism of the optical head 1 based on an electric signal generated by the light receiving element (not shown) of the optical head 1 according to the amount of received light, similarly to the above-described RF amplifier. Generate a tracking error signal for servo control. Similarly, the focus error signal generation circuit generates a focus error signal for servo-controlling the focus control mechanism of the optical head 1 based on the electric signal of the light receiving element (not shown).
[0029]
The optical head servo circuit 3 is a servo mechanism (tracking servo mechanism or focus servo mechanism) incorporated in the optical head 1 based on various error signals (tracking error signal, focus error signal, etc.) generated by the front end processing unit 2. A servo control signal for driving the mechanism. Then, the servo control of the servo mechanism is performed based on the servo control signal.
[0030]
The WBL detection unit 4 includes a BPF (Band Pass Filter) circuit, a comparator, and the like. In this configuration, the BPF circuit receives the RF signal generated by the front-end processing unit 2 and extracts a wobbling frequency component (center frequency 22.05 kHz) from the received RF signal. By comparing the wobbling frequency component with a reference voltage using a comparator, a WBL (Wobble) signal (“wobbling information”) as binary data is transmitted to the ATIP decoder 5 and the motor control circuit 17.
[0031]
The ATIP decoder 5 decodes an ATIP address based on a WBL signal per ATIP section (described later) received from the WBL detection unit 4. Here, a WBL signal per ATIP section includes a pattern for synchronization detection, an identifier assigned to a recording area where the WBL signal is recorded, wobbling information including an ATIP address, and a CRC (CRC) for error detection. Cyclic Redundancy Code) data (“information for address inspection”) is included (see FIG. 2).
[0032]
The ATIP decoder 5 has a CRC check circuit (“address information checking means”) 5a. The CRC check circuit 5a performs a CRC check based on the above-mentioned CRC data in order to determine whether or not the ATIP address has been correctly decoded from the WBL signal per ATIP section. Note that the determination of the decoding result of the ATIP address is not limited to the above-described CRC check. For example, a parity check method using horizontal / vertical parity bits (“information for address check”) or an ECC (Error) Other error correction / detection schemes such as an ECC check scheme using Correcting Code (“address inspection information”) may be employed.
[0033]
The processing content of the PSN decoder 6 differs between the case where the optical disc 200 is in an unrecorded state and the case where the optical disc 200 is in a state where high-density recording is performed using a PSN (Physical Sector Number) address as a high-density recording address.
First, a process when the optical disc 200 is in an unrecorded state will be described. In this case, upon receiving the ATIP address decoded by the ATIP decoder 5, the PSN decoder 6 decodes the PSN address as a high-density recording address based on the received ATIP address.
[0034]
Next, a process when the optical disc 200 is in a state of high-density recording using a PSN address as a high-density recording address will be described. In this case, in a recording area (partition area) logically divided by the PSN address, ID (Identification Data) information associated with the PSN address is recorded together with the actual data (see FIG. 3). . This ID information serves as information for the optical disc apparatus 100 to identify the above-described sectioned area. Further, in the above-described partitioned area, a parity bit for checking a bit error or the like of data including ID information is also recorded (see FIG. 3). Note that the PSN address itself may be recorded in the above-described section area.
[0035]
That is, the PSN decoder 6 receives the ID information included in the RF signal generated by the front-end processing unit 2, and decodes the PSN address based on the received ID information. At the time of decoding, the parity bit is received together with the ID information, and the parity check of the ID information is performed based on the received parity bit.
[0036]
The PLL circuit 7 includes a phase comparator, a charge pump, an LPF, a VCO, a frequency divider, and the like (all not shown). In this configuration, the PLL circuit 7 generates a clock signal as a timing signal used in a decoding process according to the standard of the optical disc 200, based on the WBL signal received from the WBL detection unit 4.
[0037]
The high-density recording mode decoder 8 performs a decoding process according to a logical format adopted for a reproduction process on the optical disc 200 in the high-density recording mode. In the present invention, a decoding process according to a logical format defined by the DVD standard is adopted. In the DVD standard, EFM-plus is used as a modulation code, and RS (Reed Solomon) Product-Code is used as an error correction code. Therefore, the high-density recording mode decoder 8 outputs these signals based on the clock signal generated by the PLL circuit 7 and the RF signal generated by the front-end processing unit 2 (the input line of the RF signal is not shown). It is assumed that decoding processing based on the modulation code and the error correction code is performed.
[0038]
The high-density recording mode encoder 9 performs an encoding process on recording data input from an information processing device (not shown) such as a personal computer via the interface unit 14 in accordance with a logical format adopted in the high-density recording mode.
In the present invention, an encoding process according to a logical format defined by the DVD standard is employed in connection with the high-density recording mode decoder 8. The encoding process includes a process for forming an ECC block which is an error correction unit at the time of recording / reproducing, an EFM-plus modulation process, a scrambling process, and the like. The modulation signal is transmitted to the laser output control circuit 13.
[0039]
The interface unit 10 controls transmission and reception of recording / reproducing data between the optical disc device 100 and an information processing device (not shown) such as a personal computer.
[0040]
When a reproduction request is received from the information processing apparatus (not shown) via the interface unit 10, the RAM 11 temporarily stores intermediate data being decoded by the high-density recording mode decoder 8 and reproduction data after the decoding processing. I do. The temporarily stored reproduction data is transmitted to the information processing device (not shown) via the interface unit 10.
Further, the RAM 11 temporarily stores the recording data when the recording data as a target of the recording request is received from the information processing device (not shown) via the interface unit 10. The temporarily stored recording data is accessed at the time of the encoding process in the high-density recording mode encoder 9.
[0041]
The system control microcomputer 12 controls the overall system control of the optical disc device 100 related to recording and reproduction of the optical disc 200. In the present invention, the system control microcomputer 12 has a mechanism for executing the following interrupt processing for the ATIP decoder 5 and the PSN decoder 6.
[0042]
First, as an interrupt process for the ATIP decoder 5, the CRC check circuit 5a of the ATIP decoder 5 performs a CRC check on an ATIP address for each ATIP section constituting a recording area for one ECC (Error Correction Code) block which is a recording / reproducing unit. In this case, a mechanism for acquiring information on the CRC check result (hereinafter, referred to as CRC check result information) is adopted.
On the other hand, as an interrupt process for the PSN decoder 6, when the PSN decoder 6 decodes the PSN address for the first ATIP section in the recording area for one ECC block, the PSN decoder 6 acquires the decoded PSN address.
[0043]
The system control microcomputer 12 has a CRC check result determination unit 12a and an access control unit 12b in addition to the above-described mechanism.
The CRC check result determination unit 12a counts the value of the predetermined parameter K when the CRC check result information obtained by the above-described interrupt processing is information indicating that the decoded ATIP address is not normal. It is updated by incrementing or decrementing ("first parameter value updating means"). Note that the value of the parameter K is reset to an initial value every time CRC check result information is obtained for all ATIP sections (8 ATIP sections) constituting a recording area for one ECC block.
[0044]
By the way, when the CRC check result information acquired by the above-described interrupt processing is information indicating that the decoded ATIP address is normal, the CRC check result determination unit 12a determines whether the predetermined AT The value may be updated ("second parameter value updating means"), but in the following description, updating is performed by the above-mentioned "first parameter value updating means".
[0045]
Further, the CRC check result determination unit 12a compares the predetermined threshold value A (0 ≦ A ≦ 8) with the updated value of the parameter K, and assigns the value to the 8 ATIP sections constituting the recording area for one ECC block. For each of the ATIP addresses determined, it is determined whether or not the number of ATIP addresses identified as abnormal is greater than or less than threshold A ("first threshold determination means").
[0046]
Note that the CRC check result determination unit 12a determines that the number of ATIP addresses identified as normal for each of the ATIP addresses assigned to the eight ATIP sections constituting the recording area for one ECC block is smaller than the threshold value A by the above-described control. It may be determined whether it is greater or less (“second threshold value determining means”), but in the following description, the determination by the above-mentioned “first threshold value determining means” is performed. .
[0047]
The access control unit 12b controls access to the optical disc 200, that is, data recording / reproducing processing, using the PSN address obtained by the interrupt processing for the PSN decoder 6.
For example, in the case of a seek operation, the access control unit 12b updates the obtained PSN address to a PSN address corresponding to a target track position to be recorded / reproduced specified by the information processing device (not shown). The updated PSN address is transmitted to the optical head servo circuit 3. The optical head servo circuit 3 controls a slide mechanism (not shown) of the optical head 1 to move the optical head 1 based on the PSN address received from the access control unit 12b, so that the light spot moves to the target track position. Servo control is performed to position the optical head 1 at a location where light is irradiated.
[0048]
When data is actually recorded from the target track position after the seek operation, the access control unit 12b sets the RAM 11 in the recording area (8 ATIP sections) for one ECC block specified by the PSN address of the target track position. The encoder 9 for the high-density recording mode and the like are controlled in order to start the encoding process of the recording data temporarily stored in.
[0049]
Similarly, when data is actually reproduced from the target track position after the seek operation, the access control unit 12b sets the reproduction data from the recording area (8 ATIP section) for one ECC block specified by the PSN address of the target track position. The high-density recording mode decoder 8 and the PLL circuit 7 are controlled in order to start the decoding processing of the.
[0050]
The laser output control circuit 13 generates a pulse signal for driving the laser element 1a to emit laser light based on the recording modulation signal received from the high-density recording mode encoder 13. This pulse signal is transmitted to the laser drive circuit 14. The laser output control circuit 13 determines the characteristics of the recording layer of the optical disc 200 and the spot shape of the laser beam B under the control of the system control microcomputer 12, and optimizes the laser beam B emitted from the laser element 1a. Processing for setting the output level is also performed.
[0051]
The laser drive circuit 14 drives the laser element 1a to emit laser light at the time of data recording based on the pulse signal received from the laser output control circuit 13. As a result, the laser beam B is emitted from the laser element 1a, and pits corresponding to the recording modulation signal output from the encoder 9 for the high-density recording mode are formed on the track of the optical disk. During data reproduction, the laser element 1a is driven to emit laser light under the control of an APC (Automatic Power Control) circuit (not shown) provided inside or outside the front end processing unit 2. The optical head 1 is provided with a detector (not shown) for detecting the power of the laser beam B emitted from the laser element 1a, and the APC circuit is provided with a laser beam detected by the detector. While monitoring the power of B, control is performed so that the power of the laser beam B emitted from the laser element 1a becomes constant.
[0052]
The spindle motor 15 is a motor that drives the optical disc 200 to rotate, and the motor drive circuit 16 is a circuit that drives the spindle motor 15 to rotate. The motor control circuit 17 is a circuit for controlling the rotation drive of the spindle motor 15 in a constant linear velocity method according to the CD standard using information on the wobbling frequency based on the WBL signal received from the WBL detection unit 4. Alternatively, the rotation drive of the spindle motor 15 may be controlled by a constant angular velocity method using a pulse signal generated according to the rotation of the spindle motor 15.
[0053]
<Data structure of high-density recording mode>
The high-density recording mode as a logical format adopted by the optical disc apparatus 100 for recording / reproducing processing on the optical disc 200 which is a CD standard medium such as a CD-R or a CD-RW will be described in detail.
[0054]
First, the data structure in the standard recording mode will be described with reference to FIG.
As shown in the figure, the minimum unit of data recorded on a CD standard medium is one EFM frame based on the EFM (Eight to Fourteen Modulation) modulation method of the CD standard. Then, one frame of 588 bits is constituted by the 98 EFM frame. Also, one frame generates subcode data (including a track number, index information, an absolute / relative address, etc.) composed of “P, Q, R,..., W”.
[0055]
Further, an absolute address corresponding to the wobbling information of the track is provided from the inner track to the outer track of the CD standard medium. This absolute address corresponds to an ATIP address as absolute time information. The ATIP address is usually composed of 24 bits of data, with the upper 8 bits indicating “minute”, the subsequent 8 bits indicating “second”, and the lower 8 bits indicating “frame”. In addition, each data of "minute", "second", and "frame" is represented by a binary-coded decimal number (BCD).
[0056]
The number of frames per second is “75” (00 to 74 frames). Here, a recording area set by an ATIP address corresponding to “1/75” second (hereinafter, referred to as one ATIP section; “first recording area”) is one sector treated as a recording / reproducing unit in the optical disc apparatus 100. It becomes. The recording area for one sector is usually composed of 2 kbytes, and records a sync pattern, an identifier, wobbling information, CRC data and the like as described above.
[0057]
FIG. 3 shows a data structure in the high-density recording mode. In this high-density recording mode, for example, a recording density 2.0 times that of the standard recording mode is realized. In this case, in one ATIP section, data of two sectors, that is, 4 kbytes of data is recorded. In this case, in the recording area for one sector, ID information associated with the PSN address, recording data, ID information, parity bits for checking the recording data, and the like are recorded.
[0058]
Further, as described above, in the high-density recording mode, since the modulation / demodulation method conforming to the DVD standard is adopted, the recording / reproducing unit in the optical disc device 100 is one ECC (Error Correction Code) block. The data for one ECC block is recorded in a recording area (“second recording area”) corresponding to 8 ATIP sections. That is, data of 16 sectors (32 kbytes) is recorded in the recording area of one ECC block.
[0059]
<Relationship between ATIP address and PSN address>
=== Physical format ===
The physical format of the optical disc 200 adopted in the high-density recording mode will be described.
The physical format of the optical disc 200 is, for example, as shown in the upper part of FIG. As shown in the figure, the format area, PCA (Power Calibration Area), PMA (Program Memory Area), TOC (Table Of Contents) area, TOC (Table Of Contents) area, program area, and readout from the inner circumference to the outer circumference of the optical disc 200. An area is provided.
[0060]
In the format area, predetermined data (for example, all “0”) is recorded when the format processing of the optical disc 200 is performed in the high-density recording mode. The PCA is provided with a test area for performing test writing as setting control of the recording power of the laser element 1a, and a counter area for storing an address in the test area where the test writing is performed and the number of times of test writing.
The PMA is used as an area for temporarily recording recording mode information, recording start and end time information, etc. every time recording is performed on a track. After all the planned tracks are recorded, TOC information generated based on the information recorded in the PMA is recorded in the TOC area.
The program area is a user-usable area for recording and reproducing actual data. The lead-out area is an area for identifying the end position of recording and reproduction of the optical disc 200.
With the above configuration, the physical format adopted in the high-density recording mode has no pre-gap area compared to the physical format conforming to the existing CD standard, and high-density recording is possible.
[0061]
=== ATIP address ===
The ATIP address will be described in detail.
The middle part of FIG. 4 shows ATIP address setting information obtained by the optical disc apparatus 100 decoding physical wobbling information of the pre-groove of the optical disc 200. The ATIP address has one side as a physical address assigned to a track of the optical disc 200 and one side as a logical address used by the optical disc apparatus 100 to control recording or reproduction on the optical disc 200.
[0062]
The ATIP address corresponding to the innermost side of the program area (hereinafter, referred to as a first reference ATIP address) is “00 (minute): 00 (second): 00 (frame)”. Then, in the recording area from the innermost side to the outermost side of the program area (hereinafter referred to as the outer peripheral side recording area), the first reference ATIP address is calculated by converting "1 second = 75 frames". Are simply increased in units of one frame. In the present invention, the maximum value of the ATIP address in the outer recording area is set to “89 (minute): 59 (second): 74 (frame)”.
[0063]
On the other hand, a recording area on the inner side of the first reference ATIP address (hereinafter referred to as an inner recording area) is a reserved area such as PCA or PMA which cannot be used by the user. An ATIP address is also assigned to this inner recording area. In the present invention, for example, the minimum value of the ATIP address in the inner recording area (hereinafter, referred to as a second reference ATIP address) is set to “90 (minute): 0:00 (second): 00 (frame)”. . Then, in the inner recording area, similarly to the outer recording area, an ATIP address which is obtained by simply increasing the second reference ATIP address by one frame in terms of “1 second = 75 frames” is assigned. Is done.
[0064]
=== PSN address ===
The PSN address will be described in detail.
The lower part of FIG. 4 shows PSN address setting information used as a logical address when the optical disc apparatus 100 performs recording or reproduction on the optical disc 200 in the high-density recording mode.
[0065]
Here, the PSN address indicates an address (y) for high-density recording calculated by “y = n × (x−m) + m” when an absolute address as the ATIP address is “x”. . Here, “n” is the magnification for the recording density (the magnification in the standard recording mode is 1), and if the recording density is 2.0 times, “n = 2.0”. “M” is a reference address.
[0066]
That is, according to the logical format of the high-density recording mode, the PSN address is obtained by multiplying the recording area (1 ATIP section) corresponding to a unit time (“1/75” second) based on the absolute address “x” by the recording density magnification (n). This is assigned to a logically divided area of one ATIP section divided by. By this high-density recording using the PSN address, n times data is recorded in one ATIP section, and as a result, the recording density of the optical disc 200 becomes n times.
[0067]
In the present invention, the magnification (n) of the recording density is "2", and the PSN address (m) on the innermost side of the program area is "30000H (Hexadecimal: hexadecimal)". In this case, the PSN address (y) associated with the ATIP address of the outer recording area is calculated as “y = 2 × (x (hexadecimal) −30000H) + 30000H”. For example, the PSN address corresponding to the ATIP address of “00 (minute): 00 (second): 01 (frame)” is “30002H = 2 × (30001H−30000H) + 30000H”.
[0068]
<Operation of system control microcomputer>
Hereinafter, the operation of the system control microcomputer 12 which is responsible for the characteristic processing in the present invention will be described in detail.
[0069]
=== Setting of CRC_NG flag value ===
FIG. 5 is a flowchart illustrating a process in which the system control microcomputer 12, particularly the CRC check result determination unit 12a, sets a CRC_NG flag value for each ECC block.
[0070]
First, the system control microcomputer 12 obtains an ATIP address, CRC check result information, and a PSN address for the first one ATIP section constituting a recording area for one ECC block by interrupt processing for the ATIP decoder 5 and the PSN decoder 6 ( S500).
The CRC check result determination unit 12a determines whether the CRC check result information acquired in S500 is information that has been identified as not normal (S501). Here, when the CRC check result information acquired in S500 indicates that the information is not normal (S501: YES), the value of the predetermined parameter K is increased by +1 unit from the initial value (for example, “0”). Is counted up (S502). On the other hand, if the CRC check result information acquired in S500 indicates that the information has been identified as normal (S501: NO), the parameter K is left as it is.
[0071]
Incidentally, the recording area of one ECC block corresponds to 16 sectors. Therefore, the PSN address assigned to the first sector of the recording area for one ECC block is updated by 16 PSN addresses, so that the least significant four bits are “0”.
Therefore, in order to execute the above-described process of counting the value of the parameter K for each of the 8 ATIP sections constituting the recording area for one ECC block, the least significant four bits of the PSN address acquired in S500 are set to “0”. Is determined (S503).
[0072]
As a result of the determination in S503, when the least significant 4 bits are not “0” (S503: NO), the CRC check result information is transmitted from the ATIP decoder 5 to the next 1 ATIP section constituting the recording area for one ECC block. It acquires (S504), and executes the steps from S501 to S503 again. In step S504, every time the system control microcomputer 12 acquires the CRC check result information of all the ATIP addresses assigned to the 8 ATIP sections constituting the recording area for one ECC block, the system control microcomputer 12 executes the interrupt processing to the PSN decoder 6 to execute the processing. The PSN address corresponding to the first ATIP section of one ECC block is obtained.
[0073]
On the other hand, as a result of the determination in S503, when the least significant 4 bits are “0” (S503: YES), the parameter K of the above-described parameter K is set for all the 1 ATIP sections constituting the recording area for one ECC block. This means that the value has been counted. Then, the CRC check result determination unit 12a compares the counted value of the parameter K with a preset threshold A to determine whether the value of the parameter K is larger than the threshold A (S505).
[0074]
Here, when the value of the parameter K is larger than the threshold value A (S505: YES), a predetermined CRC_NG flag value is set to "1" indicating that the recording area for the one ECC block is not normal (S506). On the other hand, if the value of the parameter K is equal to or smaller than the threshold A (S505: NO), the CRC_NG flag value is set to “0” indicating that the recording area for the one ECC block is normal (S507).
In this manner, the CRC_NG flag value is set for each ECC block by the CRC check result determination unit 12a of the system control microcomputer 12.
[0075]
In the above-described embodiment, the number of pieces of CRC check result information indicating that the ATIP address is not normal among all the ATIP addresses assigned to the recording areas for a plurality of (two or more) ECC blocks is described. The CRC_NG flag value may be set to “0 (normal)” or “1 (abnormal)” by counting and comparing the count value with (the number of ECC blocks × threshold value A).
[0076]
Further, in the above-described embodiment, when the CRC check result information acquired in S500 indicates that the state is not normal (S501: YES), the value of the parameter K is set to an initial value (for example, “8”). The countdown may be performed in units of -1 from. In this case, when the value of the parameter K is larger than the threshold A, the CRC_NG flag value is set to “0 (normal)”, and when the value of the parameter K is equal to or smaller than the threshold A, it is set to “1 (abnormal)”. Set.
[0077]
=== Seek operation according to CRC_NG flag value ===
For example, as shown in FIG. 6, the optical disc apparatus 100 performs a seek start position (PSN) on a track based on the current position of the optical head 1 as a pre-process for starting data recording / reproducing processing on the optical disc 200. From the address “30000H” and the ATIP address “0: 0: 0”), the seek target position (PSN address “30040H”, ATIP address “0: 0”) on the track specified by the information processing device (not shown). Until 32 ″), a seek operation for moving the optical head 1 by a slide mechanism (not shown) is performed.
Note that the seek operation mode includes a mode in which the optical head 1 (that is, a light spot) is moved in units of a plurality of ECC blocks, and a mode in which the optical head 1 is moved in units of one ECC block.
[0078]
Hereinafter, a processing flow in which the system control microcomputer 12 controls the seek operation according to the CRC_NG flag value will be described with reference to the flowchart in FIG. In the following description, the seek operation mode is a mode in which the optical head 1 is moved in units of 1 ECC block, and the seek start position and the seek target position are included in the first 1 ATIP section of the recording area for the 1 ECC block. Shall be. The following processing is executed by the system control microcomputer 12 unless otherwise specified.
[0079]
First, the system control microcomputer 12 acquires the ATIP address and the CRC check result information from the ATIP decoder 5 and the PSN address from the PSN decoder 6 for one ATIP section including the seek start position (S700).
[0080]
Then, the CRC check result determination unit 12a counts information indicating that the ATIP address is identified as not normal in the CRC check result information acquired in S700, and further counts the count value and the threshold value A. Is set, the CRC_NG flag value is set in units of one ECC block (S701). It is assumed that the set CRC_NG flag value is stored in an appropriate storage unit (not shown) in association with information on each ECC block.
[0081]
Here, the system control microcomputer 12 determines whether or not the PSN address acquired in S700 is a PSN address for one ATIP section including the seek target position (S702). In S702, if the acquired PSN address is not determined to be the PSN address for the 1 ATIP section including the seek target position (S702: NO), the state is in the seek operation, and the light spot is in the next 1 ATIP section. Will be moved to the track corresponding to.
[0082]
Then, the system control microcomputer 12 acquires the CRC check result information from the ATIP decoder 5 for the ATIP address decoded from the pre-groove of the track on which the light spot is currently irradiated (S703), and executes the processing of S701 again. .
[0083]
In step S703, each time the system control microcomputer 12 acquires the CRC check result information of all the ATIP addresses assigned to the 8 ATIP sections constituting the recording area for one ECC block, the system control microcomputer 12 executes an interrupt process to the PSN decoder 6 to execute the process. The PSN address corresponding to the first ATIP section of one ECC block is obtained.
[0084]
On the other hand, if it is determined in S702 that the PSN address corresponds to one ATIP section including the seek target position (S702: YES), it means that the optical head 1 has reached the seek target position. In this case, the system control microcomputer 12 determines whether or not all the CRC_NG flag values set for each recording area of one ECC block from the seek start position to the seek target position are set to “0”. (S704).
[0085]
If it is determined in S704 that the CRC_NG flag values are all set to “0” (S704: YES), it is determined that the seek operation has been normally performed, and the recording area of one ECC block including the seek target position is determined. The recording / reproducing process of the data is started (S705).
[0086]
On the other hand, if it is determined in S704 that the CRC_NG flag value has been set to "1" at least once or more (S704: YES), whether to execute a sea retry with a preset maximum number of retries as an upper limit is determined. It is determined whether or not it is (S706).
[0087]
Here, when the seek retry is executed (S706: YES), if the current number of times of seek retry is not the maximum number of times of retry (S707: NO), S700 is performed together with the seek retry from the seek start position to the seek target position. Steps S704 to S704 are executed again.
[0088]
If the seek retry is not executed (S706: NO), or if the current number of retries is the maximum number of retries (S707: YES), the seek operation is determined to have not ended normally and the seek operation is stopped. That is, the data recording or reproducing process for the recording area of one ECC block including the seek target position is stopped (S708). Then, the system control microcomputer 12 transmits an error code indicating that the seek operation has not been normally completed to the information processing device (not shown) via the interface unit 10.
[0089]
In the above-described seek retry, for example, the system control microcomputer 12 stores the PSN address of the seek start position, and transmits the stored PSN address to the optical head servo circuit 3. Then, based on the PSN address of the seek start position received from the system control microcomputer 12, the optical head servo circuit 3 positions the optical head 1 at a place where the light spot is irradiated on the seek start position, and then the same operation is performed again. Is to perform the servo control for the seek operation of (1).
[0090]
The above-described stop of the seek operation means that, for example, the system control microcomputer 12 controls the slide mechanism (not shown) by the optical head servo circuit 3, and encodes the recording data by the high density recording mode encoder 9. Processing, such as stopping decoding of reproduced data by the decoder 8 for high-density recording mode, the PLL circuit 7, and the like.
[0091]
As described above, the optical disc device 100 performs the CRC check of the ATIP address for each ATIP section constituting the recording area for one ECC block, together with the seek operation. Then, if the number of ATIP addresses identified as not normal (or normal) is greater than or less than a predetermined threshold A, the seek operation is stopped or retried.
[0092]
By the way, optical information is not normally read from the optical disc 200 due to a defect of the optical disc 200 itself, such as dust or dust on the optical disc 200, a flaw, eccentricity of the disc, or the like. And) the likelihood that the ATIP address will be greater than or less than threshold A.
[0093]
In such a case, the above-described processing functions effectively, so that it is possible to provide an optical disk device with improved reliability of a seek operation and a control method thereof. In particular, in the case of a seek operation before data recording, data is not recorded at an erroneous seek target position, so that useless consumption of a recording area of the optical disc 200 can be suppressed.
[0094]
=== Recording / reproducing operation according to CRC_NG flag value ===
As shown in FIG. 6, when the seek operation is normally completed, the optical disc device 100 reads data from a recording area of one ECC block including a seek target position (PSN address “30040H”, ATIP address “0: 0: 32”). The recording / playback process is started.
[0095]
Therefore, a processing flow in which the system control microcomputer 12 controls the data recording / reproduction processing according to the CRC_NG flag value after the end of the seek operation will be described below with reference to the flowchart of FIG. The following processing is executed by the system control microcomputer 12 unless otherwise specified.
[0096]
First, the system control microcomputer 12 obtains an ATIP address, CRC check result information, and a PSN address for the first one ATIP section constituting the recording area for the one ECC block by interrupt processing for the ATIP decoder 5 and the PSN decoder 6. (S800).
[0097]
The CRC check result determination unit 12a determines whether the CRC check result information acquired in S800 is information that has been identified as not normal (S801). Here, in S801, when it is determined that the information is not normal (S801: NO), the value of the predetermined parameter K is counted up from an initial value (for example, “0”) by +1 unit (S802).
[0098]
On the other hand, if it is determined that the information is normal (S801: YES), the value of the parameter K is left as it is. It is assumed that the value of the parameter K is reset to the initial value when the process of determining the CRC check result information for all ATIP addresses assigned to the 8 ATIP sections ends.
[0099]
Next, the CRC check result determination unit 12a compares the counted value of the parameter K with a preset threshold A to determine whether the value of the parameter K is larger than the threshold A (S803). . Here, when it is determined that the value of the parameter K is equal to or less than the threshold value A (S803: NO), it means that the ATIP address decoding processing for the one ATIP section has been performed normally, Perform recording and playback as usual. Subsequently, CRC check result information of the ATIP address for the next one ATIP section is obtained (S804), and the process of S801 is executed again.
[0100]
On the other hand, when it is determined that the value of the parameter K is larger than the threshold value A (S803: YES), the optical disc device 100 transmits the data from the information processing device (not shown) to the recording area of one abnormal ECC block. It is determined whether the command data for permitting the recording / reproducing process has been received (S804).
[0101]
Here, in S804, when the above-described command data is received (S804: YES), the system control microcomputer 12 executes a data recording / reproducing process for the one ATIP section. In this case, in the data recording process, the recording data specified by the information processing device (not shown) may be recorded as it is in the 1 ATIP section, or the preset meaningless data may be recorded. (For example, all “0”) may be recorded.
[0102]
If the above-described command data is not received in S804 (S804: NO), the system control microcomputer 12 performs control for stopping the data recording / reproducing process for the one ATIP section. Then, the system control microcomputer 12 transmits, via the interface unit 10, an error code indicating that the recording / playback processing has not been normally completed to the information processing apparatus (not shown).
[0103]
As described above, the optical disk device 100 performs the CRC check of the ATIP address for each 1 ATIP section constituting the recording area for one ECC block even during recording / reproducing of data. Then, when the number of ATIP addresses identified as abnormal is greater than or less than the predetermined threshold A, the data recording / reproducing process is stopped.
[0104]
The above-described stop of the data recording / reproducing processing is performed, for example, by the system control microcomputer 12 controlling the slide mechanism (not shown) by the optical head servo circuit 3 and the high-density recording mode encoder 9. This is to stop recording data encoding processing, reproduction data decoding processing by the high-density recording mode decoder 8 and the PLL circuit 7, and the like.
[0105]
By the way, optical information is not normally read from the optical disk 200 due to a defect of the optical disk 200 itself, such as dust or dust on the optical disk 200, a scratch, and eccentricity of the disk, and the optical information is not normal (or normal). 3.) It is more likely that the ATIP address will be greater than or less than threshold A.
[0106]
In such a case, the above-described processing functions effectively, so that it is possible to provide an optical disk apparatus with improved reliability in data recording / reproducing processing and a control method thereof. In particular, in the case of data recording processing, a recording area in which the ATIP address has not been decoded properly can be quickly detected, and the recording processing of data in the recording area can be stopped. Wasteful consumption can be suppressed.
[0107]
As described above, the embodiment of the present invention has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and can be variously changed without departing from the gist thereof.
[0108]
【The invention's effect】
According to the present invention, it is possible to provide an optical disk device with improved reliability and a control method thereof.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a system including an optical disk device according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating a logical format in a standard recording mode.
FIG. 3 is a diagram illustrating a logical format in a high-density recording mode.
FIG. 4 is a diagram for explaining a relationship between a physical format of an optical disc, an ATIP address, and a PSN address.
FIG. 5 is a flowchart illustrating a processing flow of a system control microcomputer according to an embodiment of the present invention.
FIG. 6 is a diagram showing an ATIP address and a PSN address which the optical disk device according to one embodiment of the present invention refers to during a seek operation and during data recording / reproduction.
FIG. 7 is a flowchart illustrating a processing flow of a system control microcomputer according to an embodiment of the present invention.
FIG. 8 is a flowchart illustrating a processing flow of a system control microcomputer according to an embodiment of the present invention.
[Explanation of symbols]
1 Optical head
1a Laser element
2 Front-end processing unit
3 Optical head servo circuit
4 WBL detector
5 ATIP decoder
5a CRC check circuit
6 PSN decoder
7 PLL
8 High density recording mode decoder
9 High density recording mode encoder
10 Interface section
11 RAM
12 System control microcomputer
12a CRC check result judgment unit
12b access control unit
13 Laser output controller
14 Laser drive circuit
15 Spindle motor
16 Motor drive circuit
17 Motor control circuit

Claims (8)

For an optical disc having address information assigned to each first recording area set in a track, the optical disc is transferred to the optical disc in units of a second recording area composed of a plurality of the first recording areas. In an optical disc device for recording or reproducing data,
Based on the result of comparing the number of the address information identified as normal among the address information assigned to each of the plurality of first recording areas constituting the second recording area with a predetermined threshold value An optical disc device comprising control means for controlling data recording or reproduction on the optical disc. The control means,
Comparing the number of the address information identified as normal among the address information included in the second recording area with the threshold, and the number of the address information is greater than or less than the threshold 2. The optical disk device according to claim 1, further comprising a threshold value determination unit that determines whether or not the optical disk device is in the optical disk. The control means,
When a seek operation for moving a light spot irradiated on the optical disc from a seek start position to a seek target position is performed, at least one of the second recording areas included from the seek start position to the seek target position 3. The optical disk device according to claim 2, wherein control for stopping the seek operation is performed based on a determination result of the threshold determination unit. The control means,
When a seek operation for moving a light spot irradiated on the optical disc from a seek start position to a seek target position is performed, at least one of the second recording areas included from the seek start position to the seek target position 4. The optical disk device according to claim 2, wherein control for retrying the seek operation with a predetermined number of times as an upper limit is performed based on a determination result of the threshold value determination unit. The control means,
For the second recording area in a state where data is being recorded or reproduced, control for stopping recording or reproduction of data in the second recording area is performed based on the determination result of the threshold value determining unit. The optical disk device according to any one of claims 2 to 4, wherein the operation is performed. The optical disc is
The address information and address inspection information for inspecting the address information are associated with the wobbling information of the track, and
The optical disc device,
Address generation means for receiving the wobbling information read from the optical disc and generating the address information corresponding to the received wobbling information;
An address information check for receiving the wobbling information read from the optical disc and for checking the address information generated by the address generating means based on the address check information corresponding to the received wobbling information. Means,
The optical disk device according to claim 1, further comprising: The control means,
Receiving address check result information indicating a check result of the address information from the address information checking means, and determining that the received address check result information indicates that the checked address information is normal; Parameter value updating means for updating the parameter value of
The threshold determination means,
By comparing the updated parameter value with the threshold, the number of pieces of address information identified as normal among the pieces of address information of the second recording area is greater than or equal to the threshold. 7. The optical disk device according to claim 6, wherein it is determined whether or not: For an optical disc having address information assigned to each first recording area set in a track, the optical disc is transferred to the optical disc in units of a second recording area composed of a plurality of the first recording areas. In a control method of an optical disc apparatus for recording or reproducing data,
Of the address information assigned to each of the plurality of first recording areas constituting the second recording area, a result of comparing the number of the address information identified as normal with a predetermined threshold value A control method for recording or reproducing data on or from the optical disk based on the control method.

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