KR100319851B1 - Test method of record carrier - Google Patents

Abstract

The present invention provides a drive test area in which an area for performing a test for determining whether recording of a disc is normally performed when recording data on a disc capable of recording and reproducing, in particular, a drive test area, is provided. Disclosed is a test method of a recording medium for recording and reproducing test data and determining whether or not recording is possible in accordance with the test results. The disc can be taken out of the recording / reproducing apparatus, so that the standard of the test method of the drive test area can be provided for the recording media that can be exchanged between different recording / reproducing apparatuses, so that the consistency of the recording / reproducing apparatus can be maintained using the same standard. In addition, it provides a standard for more objectively determining the state of the disc, and in particular, an optical recording medium capable of recording and reproducing such as a DVD-RAM can be used more stably.

Description

Test Method of Recording Media

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of optical recording and reproducing for recording and reproducing digital data on a disc. In particular, the present invention relates to recording data on a recording medium capable of repeating and reproducing, such as a digital versatile disc random access memory (DVD-RAM). It relates to a test method for determining whether stable recording is possible.

According to the DVD Specifications for Rewritable Disc (Part 1 Physical Specifications Version 1.0) published in July 1997, the DVD-RAM has a drive test area (Lead in and Lead out areas). Drive Test Zone). This drive test area is suitable for the drive test area that is not used by the user in the DVD-RAM recorder after the disc is inserted into the drive and after the disc recognition process is completed. Is an area for judging whether data is normally recorded and reproduced by performing a test for recording and reproducing.

That is, according to the DVD-RAM specification, the drive test area is an area for testing in the recording / reproducing apparatus. In addition, in the appendix of the specification, when data is recorded in the drive test area as a reference information and normal recording is not performed (No good), no operation other than reading recorded data is performed.

However, the specification does not describe a criterion for judging what should be done in the drive test area and what criteria are not normally recorded.

That is, from the standpoint of designing a recording / reproducing apparatus using a disk as a medium, there is a problem that there is no standard for judging which state is good and which state is bad by recording and reproducing data in the drive test area on what basis. will be.

According to the standard, the standard is changed by the designer who designs the recording and reproducing apparatus, and the standard for determining whether the disc is good or bad is changed according to the product. From the consumer's point of view, the same disc may be good according to the recording and reproducing apparatus. Problems that can also be defective products may arise, and test methods and judgment criteria have not been proposed to solve them.

In order to solve the above problems, an object of the present invention is to test whether a disc is good or bad in a drive test area provided on a recording medium capable of repeating recording and reproducing, such as a digital versatile disc random access memory (DVD-RAM). There is provided a test method of a recording medium for recording data and determining whether data can be recorded on a disc from the test data to be reproduced.

In order to achieve the above object, the test method of the recording medium according to the present invention provides a predetermined interval of data of a predetermined length or more in a drive test area respectively located in a lead in area and a lead out area on a disc. It is characterized in that the recording is performed a plurality of times at an abnormally separated position, and after determining the good or bad of the data from the number of errors included in the reproduced data, it is determined whether to record on the disc based on the measured number of errors.

1 is a view schematically showing a data structure of a disc according to the DVD-RAM standard.

Fig. 2 is a diagram showing a rough recording position on a disc by the test method of the present invention.

3 is a flowchart according to an embodiment of a test method for a recording medium according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a test method of a recording medium for recording and reproducing data for testing a disc in a drive test area according to the present invention with reference to the accompanying drawings, and determining the good or bad of the disc based on the test results. Will be described.

Fig. 1 schematically shows the structure of a disc according to the DVD-RAM standard. DVD-RAM discs are largely divided into a lead-in area, a lead-out area and a data area. In addition, a rewritable data zone capable of recording according to physical characteristics, an embossed data zone in which recording is not possible and the data is in the shape of a pit, and a mirror area that serves to connect the two areas It can be divided into (Mirror zone).

The lead-in area is divided into an embossed data area, a mirror area, and a rewritable area according to physical properties, and information on the physical properties of the disc is recorded in the embossed area. In addition, the rewritable area is a guard track zone that acts as a buffer again, a disc test zone used by a disc manufacturer to evaluate a disc, and a recording / playback characteristic of a drive in a recording / reproducing apparatus. The drive test zone is divided into a drive test zone, a disc identification zone used to determine the type of disc, and a defect management information zone (DMA1 & DMA2) for recording defect management information.

The lead-out area is composed of a rewritable area in a 2.6 GB (giga byte) DVD-RAM disc, which is a rewritable area of the lead-in area arranged in reverse order. That is, the defect management information area, the disc recognition area, the guard track area, the drive test area, the disc test area, and the guard track area are in this order. The rewritable area in the lead-in area is capable of recording 17 sectors per track, and the record-out area is capable of recording 40 sectors per track.

2 shows a schematic recording position of data by the test method of the present invention. In Fig. 2, the drive test area exists in the lead-in area, that is, the innermost part of the recording area on the disc and the lead-out area, that is, the outermost part of the recording area on the disc, respectively. For reference, the length of the drive test area corresponds to the length of 112 error correction blocks, respectively. One error correction block has a length of 32 KB (kilo byte) of user data. Further, in each drive test area, at least four test positions for recording and reproducing data are configured, and each test position has a position of the leading sectors recorded between adjacent test positions of 79 degrees or more and 101 degrees or less. Away from the disk.

According to the DVD-RAM standard version 1.0, the number of sectors that can be recorded in one track during a single rotation of the disc in the recordable lead-in area is 17, where the area on the track occupied by one sector is calculated in degrees. It is about 21 degrees. In order to record the data with the lowest position correlation in four places on the circumference, four pieces of data can be arranged at 90 degrees each. That is, since the area occupied by one sector is 21 degrees with respect to the position 90 degrees apart, the distance of the leading sector is actually located between at least 79 degrees and at most 101 degrees.

In the drive test area of the lead-out area, since the number of recordable sectors per track is 40 sectors, the circumferential angle occupied by one sector is 9 degrees, so that the starting position of the actual test position can be closer to 90 degrees. In addition, in the case where the actual recording density is increased, the length on the physical track occupied by one sector becomes shorter, and when converted to an angle, it becomes narrower and can be arranged closer to 90 degrees.

When the disc is inserted into the recording / reproducing apparatus, first, the information in the lead-in area is read to determine the type of the disc and the required physical characteristics. If the disc is a DVD-RAM disc, the test data is recorded in four or more different positions separated from each other by the predetermined positions described above in the drive test regions located in the lead-in area and the lead-out area. At this time, the data to be recorded can mainly use a random pattern. A method for generating such a random signal is a general technique well known to those skilled in the art, and detailed description thereof is omitted herein.

The number of errors occurred is detected from a block (normal error correction decoder) of the recording / reproducing apparatus which reads the recorded data and detects the error correction block and the physical sector number. If an error occurs that exceeds a given criterion, the test position is determined to be no good. Such a test is performed at at least eight positions, including at least four positions for the drive test region of the lead-in area and at least four positions for the drive test region of the lead-out area.

In this case, the reason for determining a defect only for a sector is that one error correction block is composed of 16 sectors, while a track is recorded in a lead-in area, i.e., one track along the disc in the innermost part of the disc. This is because the number of sectors is 17 sectors, so that one error correction block is almost one rotation of the disk.

Therefore, if a physical defect occurs that can be tolerated by the specification in a particular place, the defect will affect multiple tracks because the size is usually much larger than the width of the track. If it is determined to be a defective block due to a defect, the probability of being determined to be a defective block is increased because the adjacent tracks are affected almost the same.

That is, even if the recording start position of the test data is shifted by 90 degrees on the disc, since one error correction block spans almost one revolution of the track, each block is affected by physical defects such as scratching of the disc. Evaluation becomes hard.

In addition, the main purpose of the drive test area is to determine the degree of recording failure due to defects or deterioration of recording characteristics over the entire disk, rather than to determine whether the disk is defective or not due to local defects. By evaluating as small a unit of data as possible over a large number of regions, it is possible to prevent errors in which the entire disc is judged to be defective by local defects in a specific area.

Therefore, it is desirable to evaluate whether or not a defect occurs in one test position based on the sector within a range in which the sector disposed on the circumference of the disk does not exceed one quarter of the circumference.

The DVD-RAM standard describes a criterion for determining whether recorded data is defective. These regulations provide criteria for replacing defective sectors as part of the method of managing defects. The standard indicates the degree of error of data that must be replaced by a defect.

Section 5.6 of the specification assumes, for example, that a sector is damaged and replaced by defect management when the following conditions exist:

The criteria for determining that these sectors are defective are described in Annex K of the specification.

The criteria for generating an error that requires a slipping replacement for a sector are as follows.

(1) When there are three or more errors in the physical sector number (PID) in the sector.

(2) When the error (ECC error) due to an error correction block is four lines or more in each sector.

(3) The number of lines where an error occurs in each error correction block is 6 or more lines.

In addition, the criteria for generating an error that requires linear replacement of the error correction block is as follows.

(1) The sector includes one or more sectors in which at least three physical sector number (PID) errors are included in the error correction block.

(2) The number of lines where an error occurred in each error correction block is 8 or more

Among the criteria for each error, the slipping substitution is for a sector that is processed on a sector-by-sector basis when initializing the disc, which means that if the sector contains errors above the threshold, the slipping substitution should be performed. If the number of errors occurring during the operation is larger than the reference, it means that a defective error correction block should be replaced with an intact error correction block in a spare area.

Such a criterion is proposed as a criterion for determining whether a specific portion in which data is recorded on the disk is defective.

In the present invention, as shown in FIG. 1 and FIG. 2, predetermined data is recorded at a plurality of physically different defined positions separated by a predetermined distance from two drive test regions located in the lead-in area and the lead-out area. The length of the recorded data is limited to at least one error correction block. This is because in DVD-RAM, the minimum unit of writing at one time is an error correction block unit.

The criteria for judging whether or not the data recorded on the disc may be read by reading the data recorded in this manner is normal when no one is found at each test position that is determined to be defective according to the defect determination criteria of the sector according to the defect management criteria. If the disc is judged to be normal, the data is recorded normally, and if it is found that there is a defect even at one test position, it is more likely to be caused by a local defect of the disc. Record using the verification method. If a defect is found in two or more places at a predetermined test position, writing data to the disc is considered insecure, preventing the recording operation, and informing the user that the disc is in a bad state. It is starting.

On the other hand, in the process of testing the disc, the test can be performed while changing various recording and reproducing conditions. In other words, even if a defect sector occurs as a result of performing the recording / reproducing test on the first disk test area and the condition for recording user data on the disk is not satisfied, the test can be performed several times while changing the recording / reproducing condition. . In such a case, determination is made based on the result of having the minimum defective sector, that is, finally determined as the most optimal recording and reproduction condition among various recording and reproduction conditions.

It is desirable to determine the result under the recording and reproducing conditions where the error is minimal because the optimum recording conditions may vary depending on the disc condition.

Therefore, the present invention eliminates the difference between the respective recording and reproducing apparatus by making a reference not only in the general situation of reading or writing a disc, but also in the case of determining whether or not the data may be recorded on the disc by recording and reproducing the test data in the drive test area. There is an advantage that can prevent user confusion.

3 is a flow chart according to an embodiment of a test method for a recording medium according to the present invention, which describes a process of recording test data in a drive test area and determining whether there is a defect since the disc is inserted into a recording / playback apparatus. .

First, when the disc is inserted, information on the physical standard of the disc in the embossed data area of the lead-in area is read to check information such as whether the disc is a normal disc and which disc is it (step S101).

Next, conditions necessary for recording and reproducing are set from the physical information identified in step S101 (step S102). When the recording / reproducing condition is set, test data having a predetermined random pattern is recorded in a plurality of predetermined test positions set in each drive test area of the lead-in area and the lead-out area as described above (step S103). Reading the data recorded in the plurality of test positions to evaluate the error occurred in the process of error correction data (step S104).

It is determined whether or not there is a test position having a defective sector according to the evaluated error (step S105), and if there is no defect, normal recording is set (step S106). If there is a defect in step S105, it is determined whether or not to set the recording / reproducing condition again (step S107). When the recording / reproducing condition is set again, steps S102 to S105 are repeated.

If it is determined that the error continues to occur and it is not necessary to repeat it, it is determined how many sectors contain the defect (step S108), and when the defect occurs only a predetermined point or less (one in the embodiment), recording is performed. Set the data to be recorded using a write with verification method of verifying and recording the data at step S109. If a defective sector occurs more than a predetermined position in step S109, write protection is set to prevent writing (step S110).

The test method of the present invention may further include informing the user of the disk defect information indicating that a defective sector has occurred at a predetermined position or more and cannot record.

Disclosure of Invention The present invention discloses a criterion for determining whether it is safe to record user data on a disc that can be recorded and reproduced, particularly a DVD-RAM using a drive test area, and a test method thereof, according to the standards. If the playback device and disc are made, the same result can be obtained if the different playback devices satisfy the standard, so that there is an advantage of maintaining the consistency between each record player and disc using the disc as a medium.

Claims (13)

A method of testing a recording medium having a test area capable of testing the recording and reproduction characteristics of the recording medium at a specific position on the recording medium capable of recording and reproducing; (a) recording predetermined test data in the test area according to a predetermined procedure; And (b) determining whether or not data of the recording medium can be recorded according to a predetermined criterion according to the test data to be reproduced. The method of claim 1, wherein the predetermined procedure selects a plurality of test positions that are physically separated from each other in a drive test area of the recording medium so as to meet a predetermined condition, and each test position is equal to or greater than the length of the error correction block. A test method of a recording medium, characterized by recording test data. 3. The predetermined condition according to claim 2, wherein the predetermined condition is that in each drive test area of the lead-in area and the lead-out area of the recording medium, the positions of the start sectors between the test positions located in the same disk test area and adjacent to each other are 79 degrees on the circumference. And at least 101 degrees apart from each other. 4. The method of claim 3, wherein each drive test area has at least four test locations. The predetermined criterion according to claim 1, wherein the predetermined criterion is to record data normally when no one is found at each test position according to the defect management determination criteria, and is determined to be a defect even at a predetermined number of test positions. Write with verification, and if it is determined that the defect is at a test position exceeding a predetermined number, recording of data on the recording medium is prevented. 6. The recording medium according to claim 5, wherein the determination of a defect in the one test position is made based on this sector within a range in which no sector disposed on the circumference of the recording medium exceeds 1/4. Test Methods. The method of claim 1, further comprising reading information in a lead-in area when the recording medium is inserted to confirm the state of the recording medium. The method of claim 7, wherein step (b), (b1) determining whether there is a defective sector among the sectors recorded at each test position; and (b2) allowing the user data to be recorded if a result of the determination in step (b1) is not found in each test position. According to claim 8, wherein step (b) is, (b3) (b1) to (b) while changing the recording / reproducing condition of step (d) so that a minimum error is detected when a defective sector among the sectors recorded in each test position is determined as the result determined in step (b1). repeating step b3); And (b4) further comprising the step of allowing recording when a predetermined number of defective sectors are detected even under optimal recording and reproduction conditions after performing step (b3), and verifying the recorded data. 10. The method of claim 9, wherein the optimal recording and reproducing condition is based on a result having a minimum defective sector. 10. The method of claim 9, wherein the predetermined number is " 1. " The method of claim 9, wherein step (b) comprises: (b5) testing of the recording medium comprising the step of prohibiting the data from being recorded on the recording medium if the defective number of sectors is detected beyond the predetermined number despite the optimal recording and reproducing condition after the step (b3). Way. The method of claim 12, wherein step (b) comprises: and (b6) informing the user of recording medium defect information indicating that data cannot be recorded on the recording medium after performing step (b5).