KR100618993B1 - Method of verifying defect management area information of optical disc and test apparatus for performing the same - Google Patents

Abstract

The present invention discloses a method for confirming defect management area (DMA) information of an optical disc and a test apparatus for performing the same. The DMA verification method of the present invention selects one of a plurality of DMA information verification test modes for verifying DMA information, sets a test criterion according to the selected mode, and records / plays to be tested according to the selected verification test mode. The device generates test information from the generated / modified DMA information and executes a test mode for verifying the test information using the test criteria, instead of the disk having the actual defect according to the DMA information verification test mode. A test disc using a mirror file having predetermined defect information not related to the actual defect can be used to easily check whether the recording / reproducing apparatus can correctly decode and process the defect information.

Description

Method of verifying defect management area information of optical disc and test apparatus for performing the same}

1 is an embodiment of a test apparatus for performing a method for confirming defect management area information of an optical disc according to the present invention.

FIG. 2 is a state diagram of test discs used in the test apparatus shown in FIG. 1.

3 is a flowchart according to an embodiment of a method for checking defect management area information of an optical disc according to the present invention.

The present invention relates to the field of recording / reproducing optical discs, and more particularly, to a method for confirming defect management area information of an optical disc capable of recording / reproducing, and a test apparatus for performing the same.

Digital Versatile Disc Random Access Memory (DVD-RAM) discs have a function that can replace defects on a disc with a normal recording area. Such a function is called defect management, and information necessary for defect management is a defect management area on a disc. It is stored in a place called Defect Management Area (DMA). In the DMA, four pieces of information are repeatedly recorded at two positions in the lead-in area and the lead-out area on the disk. The DMA information is further divided into a Disc Defintion Structure (DDS), a Primary Defect List (PDL), and a Secondary Defect List (SDL).

This DMA information includes not only information about defects detected during initialization or use of the disk, but also information on free space and the start logical sector number for each zone. It contains important information.

The information contained in the DMA can be read and used immediately, but it also includes information that changes depending on the location and number of defects on the disk. This information is based on complex calculations based on algorithms based on the defect information registered in the DMA. There are also things that can be obtained. This corresponds to the starting logical sector number or position information of the first logical sector number of each region.

Such DMA information is closely related to the physical recording position of the data, so that a disk on which one DMA information is created or revised can be used by another recording / reproducing device, that is, moving like an optical disk. Possible recording mediums have a problem of compatibility between recording / reproducing apparatus when the DMA information is wrong. To solve this problem, there is a need for a means and method for verifying that the recording / reproducing apparatus correctly decodes the DMA information from the disc and correctly records the DMA information on the disc.

Accordingly, it is an object of the present invention to detect defects on a disc through an optical disc recording / reproducing apparatus and to confirm whether or not DMA information on the disc is correctly generated / modified in recording information on the defect in the defect management area (DMA). To provide a method for doing so.

It is another object of the present invention to detect defects on a disc through a DVD-RAM recording / reproducing apparatus capable of repeating recording / playback a plurality of times, and in generating DMA information on defects, the DMA information on the disc is accurately generated / modified. It is to provide a way to check if there is.

It is still another object of the present invention to provide a test disc using predetermined defect information not related to the actual defect, and to maintain the same condition without being affected by the actual state of the disc in which the defect information is formed in the optical disc recording / reproducing apparatus. The purpose is to provide a method for verifying that defect information can be correctly decrypted and processed.

It is still another object of the present invention to detect defects on a disc through an optical disc recording / reproducing apparatus and to confirm whether or not DMA information on the disc is correctly generated / modified in recording the information on the defect in the defect management area (DMA). To provide a test apparatus for

It is still another object of the present invention to use a test disc that uses predetermined defect information not related to an actual defect, so that the recording / playback apparatus is properly affected under the same conditions at all times without being affected by the actual state of the disc on which the defect information is formed. The present invention provides a device for testing whether defect information can be decrypted and processed.

In order to achieve the above objects, the method for confirming defect management area information of an optical disc according to the present invention is to properly generate / modify DMA information in a recording / reproducing apparatus for recording / reproducing an optical disc having defect management area (DMA) information. A method of confirming whether or not: a method of selecting one of a plurality of DMA information verification test modes for verifying DMA information, setting a test criterion according to the selected mode, and a record / test to be tested according to the selected verification test mode And generating test information from the DMA information generated / modified by the playback device and executing a test mode for checking the test information by using the test criteria.

The test apparatus for confirming the defect management area information of the optical disc according to the present invention is capable of recording / reproducing, and the DMA information is properly recorded in the recording / reproducing apparatus for recording / reproducing the optical disc having the defect management area (DMA) information. A device for testing whether to be created / modified: A test disk in which a DMA mirror file of a selected mode is recorded among a plurality of DMA information verification test modes for verifying DMA information is executed after executing a selected mode in a recording / reproducing apparatus. A retrofit drive device that generates DMA information generated / modified from the disc as test information, and a checker for comparing the test information with predetermined test information of a selected mode and confirming a test result is included.

Hereinafter, a method of confirming defect management area information of an optical disc and a test apparatus for performing the same according to the present invention will be described with reference to the accompanying drawings.

The optical disk used in the present invention is for a DVD-RAM of a phase change recording method having a capacity of 4.7 GB (Giga Bytes). DVD-RAM refers to a disc defined in the DVD specification for Rewritable disc version 2.0.

1 is a block diagram of a test apparatus for performing a method for confirming defect management area information of an optical disc according to the present invention.

The first test type disc (hereinafter referred to as C-1 disc: 10) is a disc having only physical defects knowingly in a predetermined position on the blank disc. Drive to be tested (20) generates DMA information by performing initialization or certification without certification on C-1 disk 10, C-1 The DMA information generated on the disc 10 is recorded. A disc with a DMA provided from the drive 20 to be tested (Disc with DMA) 30 is mounted in a modified drive 40 capable of reading DMA information.

Retrofit drive 40 may be referred to as a reference drive as a test-only drive manufactured by the manufacturer. The retrofit drive 40 reads only the DMA information recorded on the disk 30 having the DMA and generates the read DMA information as a DMA mirror file 50 on a file system. In addition, the drive 20 to be tested is, for example, a DVD-RAM recording / reproducing apparatus, and cannot generate DMA information into a mirror file.

The recording / reproducing system of the DVD-RAM recording / reproducing apparatus may include a file system layer, a host interface layer connecting the host computer and the recording / reproducing apparatus, a physical drive layer for recording / reproducing a physical signal, and When divided into recording media layers, etc., recording and decryption of DMA information are performed because the physical sector number of the disk is assigned by the recording medium and the physical drive, and the logical sector number of the disk is assigned by the host interface and file system. Is done below the physical drive hierarchy.

In general, in the case of recording data on a recording medium through a computer, a position to record is determined by using a logical sector number through a file system. The location of the file determined by the logical sector number is logical relative position information, and the process of converting the physical sector number to actual physical data to be recorded in accordance with the physical condition of the disk such as a defect when performing a write operation on the drive. This is necessary. However, when recording user data in an actual file system, only the logical sector number is used to transfer user data to the recording / reproducing apparatus, and the recording / reproducing apparatus transmits the logical sector number to the physical sector number where the actual data should be recorded. The defect management information is used during the conversion. Therefore, when the defect management information is incorrectly read and recorded incorrectly by one recording / reproducing apparatus, there is a problem that the correct data cannot be read or written by the other recording / reproducing apparatus.

In addition, in the case of DVD-RAM discs, all defect management is handled by the drive, so the file system or host interface can record / play back files without knowing this physical defect management, so that most drives write or play in the defect management area. Not only is it impossible to reproduce, but there are no standard commands for recording / reproducing in this defect management area. However, in order to determine whether the information in the defect management area is properly formed, it is necessary to make the data readable on a computer that can analyze it in any form. It should be recordable. To do this effectively, the retrofit drive is adapted to record / reproduce information in the defect management area. The design or modification of such a retrofit drive is easily described by those skilled in the art, and thus the description thereof is omitted.

The identifier 60 is previously stored with a DMA mirror file 50 for the C-1 disk 10 created on the drive 20 to be tested and read by the retrofit drive 40 or not shown in the figures. The manufacturer / user can compare the reference DMA mirror file for the C-1 disk 10 provided from the outside (controller for generating the DMA mirror file) in the application and test the results of whether the DMA information according to the initialization has been properly generated. Notify Here, the DMA mirror file may be referred to as test information, and the reference DMA mirror file may be referred to as predetermined test information.

The identifier 60 is not only a reference DMA mirror file for the C-1 disk 10 but also a reference DMA mirror file and a third test type disk C for a second test type disk (referred to as C-2 disc: 11). -3 disk: a reference DMA mirror file for 12) and a reference DMA mirror file for a fourth test type disk (called C-4 disk: 13) are stored or provided from outside.

On the other hand, the adder 70 adds the reference DMA mirror file 1 for the C-2 disk on the C-1 disk 10 and provides the converted drive 40 to the retrofit drive 40. Provide (11). Here, the adder 70 is provided outside the retrofit drive 40 to aid in the understanding of the present invention, but in practice, the adder 70 is preferably embedded in the retrofit drive 40. That is, it means to write the reference DMA mirror file for the C-2 disc on the C-1 disc 10 by using the retrofit drive 40.

The characteristic of the reference DMA mirror file 1 for the C-2 disk has a predetermined content of DMA regardless of the defect status of the disk on which the C-2 mirror file is to be written, and the Supplementary Spare Area (SSA). This is not full.

The drive 20 to be tested has one of three reinitialization modes, that is, a reinitialization with certification mode and an SDL list conversion when the C-2 disk 11 is mounted. Perform reinitialization with SDL list conversion mode or Reinitialization with clearing G2 list and SDL mode to generate / modify DMA information and generate / modify by the reinitialization mode performed. A disk 30 having revised DMA information is provided. When the disk 30 having the DMA information generated / modified by reinitialization is mounted, the reconstructing drive 40 generates only the DMA information as a mirror file and provides the DMA mirror file 50 to the identifier 60.

Here, the reinitialization with certification mode is a mode for initializing a disk by maintaining only the P list. The reinitialization with certification mode maintains the P list as it is and cleans up the old G1 list, the old G2 list and the SDL before reinitialization. Defects discovered by verification of all sectors upon disposition and reinitialization are registered in the new G1 list, where the new G2 list and the new SDL are null, but the defects found during verification of all sectors If the registered new G1 list is in an overflow state, it can be registered in the new SDL.

Here, the defect sectors inspected at the factory are called P lists, the defect sectors generated at the time of user verification are called G1 lists, and when reinitialization, the old SDL converted before reinitialization is called G2 list. P list, G1 list and G2 list belong to PDL.

Reinitialization with SDL list conversion mode eliminates SDL items processed by a linear replacement algorithm, and 16 ressigned sectors included in the defective block in the SDL items. Mode to replace PDL items (i.e., G2 lists) processed by a skipping replacement algorithm, where the P list and old G1 list remain intact, and the old G2 list and old SDL items remain in the new G2 list. The new SDL is empty. However, if the converted G2 list overflows, that is, exceeds the maximum number of items that can be registered in the PDL, the remaining SDL items may be registered in the new SDL.

Reinitialization with clearing G2 list and SDL mode allows the disk to be initialized using only the P list while using the disk or removed from the reallocated sectors for linear replacement to return to the latest verified state. In this mode, the G2 list and the SDL of the PDL are disposed, and the revised PDL includes the P list and the G1 list. The three reinitialization modes described above are defined in the DVD specification for Rewritable disc version 2.0.

Therefore, it is preferable that the C-2 disc 11 for the reinitialization test contains all the defect types of P, G1, and G2. In particular, you must have enough SDL items to test the list conversion. In other words, to test the overflow status of list conversion, it is preferable to have as many PDL items as overflow occurs after list conversion. That is, when the old PDL item is m and the old SDL item is n, the maximum number of new PDL items is determined to be 7679 after the SDL list is converted to the G2 list by reinitialization. To test, you must have enough n SDL entries before reinitialization to meet the condition (m + n * 16> 7679).                     

In addition, the position of the defect on the C-2 disk is the most suitable position for judging whether the position of the starting logical sector number and the first logical sector number of each region, which are determined relatively by the position and number of defects, are formed correctly. To improve the effectiveness of the test, for example, by placing defect sectors intensively before and after the location where logical sector number 0 should be, or by placing defects at special locations such as treating the start and end sectors of each region as defects. Place the defect so that it can.

The identifier 60 compares the DMA mirror file 50 for the C-2 disk with the reference DMA mirror file for the C-2 disk in an application to see if the DMA information generated by the reinitialization mode has been properly generated / modified. Inform the manufacturer / user of the test results that they indicate.

The adder 70 adds the reference DMA mirror file 2 for the C-3 disk on the C-1 disk 10 and provides the converted drive 40 to the retrofit drive 40. ). The characteristic of the reference DMA mirror file 2 for the C-3 disk has a predetermined content of DMA regardless of the state of the physical defect on the actual disk of the disk on which the C-3 mirror file is to be written, and the additional free space is full. You have enough SDL defects.

When the drive 20 to be tested has a C-3 disk 11 installed, the drive 20 can test whether the user is properly determined that the Supplementary Spare Area (SSA) of the disk is full and informs the user. When the expansion of the additional free space is performed in the full spare area (SSA), the C-3 disk 11 has the disk 30 having the revised DMA information according to the additional free space expansion. Becomes When the disk 30 having the DMA information revised by the additional free space expansion is mounted, the reconstructing drive 40 generates only the DMA information as a mirror file and provides the DMA mirror file 50 to the identifier 60.

Here, the state that the additional free space is full does not carry information about the expansion of the additional free space, but only the information that can determine the size and location of the additional free space is changed, and after the additional free space is expanded Will change the information without adding more free space. Therefore, it is preferable to use a reference DMA mirror file when there is no reference information because it is difficult to determine whether the corresponding drive has normally extended additional free space.

In addition, when the free space pool flags included in the PDL and SDL of the reference DMA mirror file provided as the above-mentioned reference information are recorded to correspond to the state that the free space is full, the free space pool flag is further extended. After the processing, it may be set to check whether the initial free space is kept full and the additional free space is changed to not full.

In addition, the free space on the disk for defect management is divided into a primary spare area, a secondary spare area, and a supplementary spare area, and are defined as follows.

The primary free space is the first free space to be allocated when a disk is initialized for defective replacement, and is used first for skip replacement. The remaining free space can be used as a secondary free space for linear replacement. Secondary free space is a space for linear replacement of a defect occurring during the use of a disk, and refers to free space remaining or separately allocated free space used by a skip replacement among the first free spaces at the time of initialization. The additional free space is a free space for linearly replacing a defect that occurs while using a disk, and means additional free space allocated during use after initialization.

After initializing, if there is not enough free space for linear replacement while the disk is in use, the additional free space for linear replacement is allocated by gradually increasing the free space from the rear end of the logical volume space on the file system by a certain amount. For linear substitution, the reverse order is used from the very end of the logical file space.

On the other hand, the verifier 60 compares the DMA mirror file 50 for the C-3 disk with the reference DMA mirror file for the C-3 disk in the application to produce a test result of whether the additional free space is properly expanded. Notify the vendor / user. When testing the C-3 disk, additional free space is allocated from the rear of the logical volume space of the file system, so it is preferable to check whether the file system conforms to the specified standard by using the file system checker although not shown in the drawing.

The adder 70 adds the reference DMA mirror file 3 for the C-4 disk on the C-1 test disk 10 and provides the converted drive 40 to the retrofit drive 40. 13) to provide. Here, the characteristic of the reference DMA mirror file for the C-4 disk has DMA information of a predetermined content regardless of the defect state of the disk on which the C-4 mirror file is to be written, and the starting logical sector number of each region is intentionally recorded incorrectly. It is.

The drive 20 to be tested performs a recording operation when the C-4 disk 11 is mounted. In this case, a process of generating the DMA mirror file 50 by mounting the disk 30 having the DMA to the reconstructed drive 40 is performed. Provides the checker 60 with the result of performing the recording operation without going through. The drive 20 to be tested must be able to distinguish wrong starting logical sector numbers, be able to read data based on prestored DMA information, and not record any user data on the disk.

This means that if the starting logical sector number of each previously recorded area is recorded incorrectly, the previous drive is judged to be correct and the recorded situation is wrong. Therefore, the drive that recorded the previous information will not read the wrong logical sector number information recorded in the DMA. Because data is recorded using the disk, new data recorded or revised on this disk can cause serious damage to the previous data. It is desirable to read the data.

The checker 60 preferably does not perform the write operation even when the write operation is performed when the disc having the wrong starting logical sector number for each region is mounted in the drive 20 to be tested. If the recording operation is not performed when the recording operation is performed on the C-4 disc 13, the drive 20 to be tested is properly operated. If the recording operation is performed, the drive 20 to be tested is properly operated. Notify you that you are not doing it.

In addition, the test for the disc in which such a starting logical sector number is recorded incorrectly can also be performed by manual operation and judgment by a testing technician.

FIG. 2 is a state diagram of a test disk used in the test apparatus shown in FIG. 1, and when known physical defects are made in the blank reference disk 100, the C-1 disk 101 becomes C-1. The recording of the C-2 mirror file on the disk 101 results in the C-2 disk 102, and the recording of the C-3 mirror file on the C-1 disk 101 results in the recording of the C-3 disk 103. When the C-4 mirror file is recorded on the C-1 disk 101, the C-4 disk 104 is obtained. When the DMA information recorded on the C-2 disk 102, the C-3 disk 103, and the C-4 disk 104 generated in this way is erased, the state of the C-1 disk 105 is returned.

Here, the characteristic of the C-2 mirror file is that a DMA having a predetermined content is recorded regardless of a defective state of a disk on which the C-2 mirror file is to be written, and the additional free space is not full. A characteristic of the C-3 mirror file is that predetermined DMA contents are recorded, and the additional free space is full, regardless of the defective state of the disk on which the C-3 mirror file is to be recorded. A characteristic of the C-4 mirror file is that the starting logical sector number of each region is deliberately erroneously recorded among the predetermined DMA contents regardless of the defect state of the disk on which the C-4 mirror file is to be recorded.

The reason for creating a test disc using a mirror file is that it is difficult to create thousands of real defects at predetermined defect locations. In addition, even if a defect is made at a predetermined position, a defect occurs at an undesired position, and thus, when a DMA is formed through a normal process of such a disk, defect information due to physical characteristics of each disk is different. In particular, the C-2 disk is difficult to manage or provide as a standard disk because the DMA information is revised by re-initialization once used, making the disk unusable for C-2 disk testing. As a result, a test disk can be created from a mirror file, since standardized DMA content and a modified drive that can write it can always be created and tested with the same conditions.

In FIG. 3, which is a flowchart according to an embodiment of a method for confirming defect management area information of an optical disk according to the present invention, a DMA confirm test mode is set through a confirm menu or a key (step S101). Verification test mode displayed when DMA verification test mode is set (first verification test mode: initialization mode with verification, initialization without verification mode, second verification test mode: reinitialization mode with verification, reinitialization mode with list conversion , A re-initialization mode for clearing the defect list, a third verification test mode for confirming whether the additional free space is expanded, and a fourth verification test mode for confirming whether or not to record by the wrong DMA) (step S102). The DMA mirror file according to the selected verification test mode is selected (step S103).

The selected verification test mode is executed using the selected DMA mirror file (step S104). That is, if the selected verification test mode is the initialization mode without verification, the C-1 disk is used to check whether the DMA structure is followed by the test apparatus shown in FIG. 1 and the starting logical sector number of each region. In the initialization mode with verification, a C-1 disk is used to check whether the DMA structure is followed by the test apparatus shown in FIG. 1, a list of defects for known defects of the C-1 disk, and the starting logic of each region. Check the sector number. In the reinitialization mode with verification, a C-2 disk is used to check whether the DMA structure is followed by the test apparatus shown in FIG. 1, to check if the P list is maintained, and to check for a known defect of the disk ( Check the defect list, and check the starting logical sector number of each region. The reinitialization mode with list conversion checks whether the DMA structure is maintained by the test apparatus shown in FIG. 1 using a C-2 disk, checks whether the P and G1 lists are maintained, and the PDL and SDL for list conversion. Check the number and start logical sector number of each region. The reinitialization mode with clearing uses a C-2 disc to check whether the DMA structure is followed by the test apparatus shown in FIG. 1, whether the P and G1 lists are maintained, and whether the G2 list and SDL are cleared. Check the start logical sector number of each region. The third verification test mode for confirming the expansion of the additional free space checks whether the DMA structure is followed by the test apparatus shown in FIG. 1 using a C-3 disk, and checks whether the file system is followed by the file system checker. do. The fourth verification test mode for testing the starting logical sector number checks whether a wrong starting logical sector number is discriminated by the test apparatus as shown in Fig. 1 using a C-4 disk, and does not record user data on the disk. Check it.                     

 After the confirmation mode selected in step S104 is executed, the test result of the confirmation mode executed is displayed (step S105), and the process ends. Although not shown in FIG. 3, the process proceeds to step S102 to perform another step S103, S104, S105 to select another confirmation mode, and the above-described process may be repeated until the end mode is set.

As described above, the present invention correctly decodes defect information in a recording / reproducing apparatus by using a test disc using a mirror file having predetermined defect information not related to the actual defect, instead of the disc having the actual defect according to the test type. There is an effect of easily checking whether it can be processed and a simple and inexpensive test device.

Claims (41)

A method for confirming that DMA information is properly generated / modified in a recording / reproducing apparatus for recording / reproducing an optical disk having defect management area (DMA) information: (a) selecting one of a plurality of DMA information verification test modes for confirming DMA information and setting a test criterion according to the selected mode; (b) generating test information from the DMA information generated / modified by the recording / reproducing apparatus to be tested according to the selected confirmation test mode; And (c) executing a test mode of verifying the test information using the test criteria. The method of claim 1, wherein the test information is configured in the form of a DMA mirror file, and the test information is read directly from the DMA area of the disk used for the test. delete The method of claim 1 wherein the method is and (d) displaying the test results of the confirmation test mode executed in step (c). The method of claim 1, wherein the plurality of DMA information verification test modes comprise a first verification test mode for testing generation of DMA information according to an initialization mode with verification and an initialization mode without verification, a reinitialization mode with verification, and list conversion. A second verification test mode for testing the generation / revision of DMA information according to a reinitialization mode having a reinitialization mode, a reinitialization mode for clearing a defect list, a third verification test mode for verifying whether or not additional free space is expanded, invalid DMA information And a fourth verifying test mode for confirming whether or not to perform recording by the test. 6. The method of claim 5, wherein in the step (b), if the confirmation test mode selected in the step (a) is the second confirmation test mode, the DMA having a predetermined content is recorded and the first free space is not full. Select the mirror file, and if the third verification test mode, the predetermined DMA contents are recorded, the additional free space is selected, the second mirror file having a full state, and if the fourth verification test mode, each region of the predetermined DMA contents Selecting a third mirror file whose start logical sector number is intentionally incorrectly recorded. 6. The method of claim 5, wherein said first verification test mode uses a first test disk having a known physical defect on a blank disk. delete delete 8. The method of claim 7, wherein in the second verification test mode, a second test disk on which the DMA of predetermined contents is recorded on the first test disk, and the first mirror file in which the additional free space is not full is recorded. Confirmation method characterized by using. delete delete delete delete delete delete delete delete delete A method for confirming that DMA information is properly generated / modified in a recording / reproducing apparatus for recording / reproducing an optical disk having defect management area (DMA) information: (a) generating test information from the DMA information generated / modified by the recording / reproducing apparatus to be tested according to a predetermined DMA confirming test mode; And (b) verifying the test information using test criteria for verifying DMA information. delete delete delete delete In an apparatus for testing whether or not DMA information is properly generated / modified in a recording / reproducing apparatus capable of recording / reproducing and recording / reproducing an optical disc having defect management area (DMA) information: Checking the DMA information for confirming the DMA information The test disk in which the DMA mirror file of the selected mode is recorded among the test modes is executed in the recording / reproducing apparatus. A retrofit drive device that generates test information; And And a verifier for comparing the test information with predetermined test information of a selected mode to confirm a test result. The test apparatus according to claim 25, wherein the test information is configured in the form of a DMA mirror file. 26. The test apparatus of claim 25, wherein the retrofit drive apparatus reads the test information from a DMA area of the test disc and provides the test information to the verifier. 27. The method of claim 25, wherein the plurality of DMA information verification test modes comprise a first verification test mode for testing generation of DMA information according to an initialization mode with verification and an initialization mode without verification, a reinitialization mode with verification, and list conversion. A second verification test mode for testing the generation / revision of DMA information according to a reinitialization mode having a reinitialization mode, a reinitialization mode for clearing a defect list, a third verification test mode for verifying whether or not additional free space is expanded, invalid DMA information And a fourth confirming test mode for confirming whether or not recording is performed by the test apparatus. 29. The test apparatus of claim 28, wherein the first test verification mode uses a first test disk having a known physical defect on a blank disk. delete delete 30. The method of claim 29, wherein in the second test confirming mode, a second test disc on which the DMA having a predetermined content is written on the first test disc, and the first mirror file in which the additional free space is not full, is recorded. Test apparatus, characterized in that the use. delete delete delete delete delete delete delete delete delete

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