JPH05298836A - Faulty sector discriminating method for optical disk - Google Patents

Abstract

PURPOSE:To check a sector which may become faulty in future by reading and judging the before/behind and right/left specific patterns of a faulty sector, deciding an alternative sector in the case of a faulty sector and recording the faulty sector information on it. CONSTITUTION:Information on a faulty sector is read, the specific pattern formed on before and behind in the circumference direction of the faulty sector and left and right in the radius direction of the faulty sector is read and it is judged whether it is a faulty sector or not from an error correcting code. If it is a faulty sector, an alternative sector is decided, the information of the faulty sector is re-recorded in the alternative sector, an operation registering the information on the faulty sector and the alternative sector is added and an alternative process is performed. Thus, suddenly unabled reading and writing operations are eliminated in an important region where reading and writing are constantly performed including a DOS's FAT region 10 and a route directory region 11 and the reliability of an optical disk is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for determining a defective sector of an optical disc.

[0002]

2. Description of the Related Art An optical disk is generally continuous in a spiral shape, and is composed of one track divided into tracks and sectors called sectors. In a 90 mm disc, one sector is divided into a header portion 1 and a recording portion 2 as shown in FIG. Since the header portion 1 of this one sector has already been embossed, only the recording portion 2 reads and writes with the optical disc drive. The actual data portion in this recording unit 2 is 512 bytes out of 639 bytes in the data field (see FIG. 2), and E for error correction is used.
CC and CRC are added. 3 shows the structure of the MO optical disk, and FIG. 4 shows the data zone 4 thereof.
It shows the contents of.

In the certify operation, in a 90 mm disc, write verification is performed with specific pattern data in the data zone 4 to check whether it corresponds to the defective sector. If it becomes a defective sector, the corresponding track and sector number are registered in PDL5. This PDL5 is an S number that does not use the registered bad sector and makes it a missing number.
Refers to the lipping method. Also, after that, REWRITABIE
Write DDS 7 which describes how to use ZONE 6. After that, data is written to and read from the REWRITABIE ZONE 6. At this time, in the write verify or read data, if there is one corresponding to the defective sector, the data which was attempted to be written or read in the defective sector is written to the replacement processing area 8 (designated by DDS7), and the defective sector is determined. The track and sector number, the track and sector number of the alternate processing area 8 are registered in the SDL 9. This SDL9 method is called Liner replacement. An address represented by such continuous tracks and sector numbers is called a physical address.
D explaining how to use WRITABIE ZONE 6
An address expressed by the DS7 excluding the alternation processing area 8 is called a logical address.

In such a configuration, the alternation processing method will be described below. The user writes the actual data in the area determined by the logical address. The user sends to the optical disk drive the first logical address to write, the sector length from it, and the matching data. As a result, the drive calculates the physical address from the logical address using the groping of the DDS7 and the information of the PDL5, confirms from the information of the SDL9 whether or not the target physical address is undergoing alternation processing, and writes the physical address to the write table. Create and write the data sent in that order. When the writing is completed, the rewritten data is read out and compared with the sent data, and if there is a sector with a prescribed error number or more, the alternation processing is performed. Of course, if a defective sector other than an error is determined during writing, replacement processing is also performed.

The cause of the error is due to insufficient writing by the drive itself, read failure, and the intention of the user.
When dust is removed, it is contained in or contained in the optical disc itself. This is because in the manufacturing process, the materials that make up the optical disc, impurities, dust, and water contained in the chemical film are entrained and adhere to the substrate or each film, or the shape is deformed or altered. Is. In this case, an error may occur immediately after manufacturing, and there are various types such as water, which takes a long time, and repeated erasing, writing, and reading.

[0006]

Generally, when a user actually records and reproduces data and the above-mentioned error exceeds a certain value as a result of the reproduction, it is registered as a defective sector. In an optical pickup, data is reproduced by traveling on a 1.6 μm track, and the reproduced data is determined by the intensity of light recorded on the optical disc. In this case, the size and the direction of the error are indefinite, so the size is not necessarily in the unit of 1.6 μm.
As a result, the intensity of the light recorded over the left and right is disturbed.
Therefore, when the disturbed signal is reproduced, the error position is not always reproduced at the same position no matter how many times it is reproduced.
Rather, there are many things that are uncertain, such as appearing or not. In addition, the cause of innately occurring in the manufacturing process, for example, the oxidation of the magnetic layer and the reflection layer, expands the oxidation range with time, which increases the error.

Therefore, once the defective sector is once determined, the probability that an error will occur in the sectors before, after, and to the left and right of the defective sector becomes the core. In the method of determining a defective sector of an optical disc, the determination process is not always performed in consideration of such a point and reliability is low.

[0008]

According to a first aspect of the present invention, information on a defective sector is read, specific patterns of sectors in the front and rear in the circumferential direction and left and right in the radial direction of the defective sector are read, and the defective sector is read from the error correction code. Determine whether or not
If it is a defective sector, a replacement sector is determined, the information of the defective sector is re-recorded in the replacement sector, and an operation of registering the information of the defective sector and the replacement sector is added to perform the replacement process.

According to a second aspect of the present invention, in the first aspect of the invention, not only the specific pattern but also various patterns written by the user are used to determine the defective sector.

According to the invention of claim 3, claim 1 or 2
In the invention described above, the time to judge whether the sectors before and after the defective sector in the circumferential direction and the left and right in the radial direction are defective sectors is one or more of the sectors in the circumferential direction before and after and in the radial direction. I did it when I read and write.

According to the fourth aspect of the invention, when attempting to certify a used or used optical disk again, the recorded defective sectors are grouped together, and the sectors in the front and rear in the circumferential direction and the sectors in the left and right in the radial direction are defective. It is determined whether the sector is a sector, and in the case of a defective sector, a simple certify operation is added to the above-described operation. ..

According to the fifth aspect of the present invention, the specific pattern is written and verified, and if a defective sector is detected, it is determined to be a defective sector, and when the information is recorded, the first defect occurs. The second specific pattern is written in and read from the sectors on the front and rear in the circumferential direction and on the left and right in the radial direction, and it is determined from the error correction code whether or not the sector is a defective sector. If the sector is a defective sector, the first and second times are determined. The alternation process is performed by performing the operation of registering the information together.

[0013]

According to the first aspect of the present invention, it is possible to eliminate the phenomenon that suddenly becomes unreadable / writable by checking the sectors that are likely to become defective in the front, back, left and right of the defective sector. ..

According to the second aspect of the present invention, it is possible to eliminate a phenomenon that suddenly becomes impossible to read and write by checking the sectors which are likely to become defective in the front, rear, left and right of the defective sector in the future. Becomes

According to the third aspect of the present invention, by checking at the time of reading or writing at least one or more of sectors which will become defective in the front, back, left and right of the defective sector, for example, DOS. It is possible to prevent sudden read / write interruptions in important read / write areas such as the FAT area and root directory area.

According to the fourth aspect of the present invention, when the optical disk used while once being certified and subjected to the alternation processing is used after being certified again, the entire PD is used.
The sum of events in which a defective sector registered in L or SDL is re-registered in PDL, and a pattern written in a sector that is likely to become defective in the front, back, left, and right of the defective sector is read and an error is corrected. If there are many,
By additionally registering as a bad sector in PDL,
Again, the time can be shortened as compared with the certifying operation of erasing, writing and verifying.

According to the fifth aspect of the present invention, sectors that are likely to become defective in the front, rear, left and right are re-certified with a pattern different from the one obtained by certifying the entire sector, so that the same qualification can be performed faster than certifying twice. It is possible to obtain the effect, and it is possible to shorten the time of the replacement process by first removing the sectors that are likely to become defective in the front, rear, left and right.

[0018]

An embodiment of the invention described in claim 1 will be described. The description of the same parts as those of the conventional example (see FIGS. 1 to 4) will be omitted, and the same reference numerals will be used for the same parts.

In the present embodiment, the structural requirements for checking the front, rear, left, and right sectors of a defective defective sector as those having a high possibility of becoming a defective sector are described. That is, the information of the defective sector is read, the specific patterns of the sectors before and after in the circumferential direction and the left and right in the radial direction of the defective sector are read, and it is judged from the error correction code whether or not the sector is a defective sector. The information of the defective sector is re-recorded in the determined replacement sector, and an operation of registering the information of the defective sector and the replacement sector is added to perform the replacement processing.

The above constituent elements will be specifically described below. When attempting to read or write to an optical disc, the physical addresses of the front, rear, left, and right sectors are calculated from the defective sectors registered in PDL5 or PDL5 and SDL9 in advance, and a specific pattern that is sequentially written is read out to cause an error. The number of events in which the correction has occurred is counted, and if the number is too large, a replacement sector is set as a defective sector, the contents of the defective sector are written to the replacement processing area 8, and the physical address thereof is registered.

Further, this does not always have to be performed, and may be performed at a certain time interval, for example, when the optical disc is inserted into the drive or conversely ejected.

Items other than error correction that result in a defective sector,
For example, even if the number of read IDs or the sector mark cannot be read, the alternation process is performed.

It is not necessary to calculate the sectors before, after, and to the left and right of the defective sector each time, and PDL5 and SDL9 are calculated.
When making the table of the list, the table of the front, back, left and right sectors may be created and referred to.

As described above, by checking the sectors which are defective and are likely to become defective in the future in the front, rear, left and right, it is possible to prevent sudden read / write failure, thereby improving the reliability of the optical disc. be able to.

Next, an embodiment of the invention described in claim 2 will be described. Here, since the specific pattern (data) written in the above-mentioned invention according to the first aspect is not necessarily used in certify, any pattern can be used. Therefore, in this embodiment, not only the specific pattern but also various patterns such as data written by the user are used to determine the defective sector.

Specifically, the number of events in which error correction has occurred is set to be strict by three or more, or the number of unreadable IDs is set to be one or less, and the number of events is set to be a bad sector. By

As described above, it is possible to eliminate the phenomenon that suddenly becomes unreadable / writable by more intensely checking the sectors that are likely to become defective in the front, back, left and right of the defective sector in the future. It is possible to improve the reliability of the optical disc. In this case, the degree of tightening may be changed between the specific pattern and other cases.

Next, an embodiment of the invention described in claim 3 will be described. In the inventions of claims 1 and 2 described above, if the monitoring is always performed, it takes a long time to execute. Therefore, in order to improve it, at least one of front, rear, left and right is read and written, and a defective sector is checked. To do. That is, in the present embodiment, the time to judge whether the sectors before and after the bad sector in the circumferential direction and the left and right in the radial direction are defective sectors is one of the sectors before and after the bad sector in the circumferential direction and left and right in the radial direction. Alternatively, it is performed when reading and writing a plurality of items.

In this case, the relevant front, rear, left and right sectors may be checked, the front and rear sectors of the bad sector near this bad sector may be included, or the front, rear, left and right sectors of all the bad sectors may be included. Good.

As described above, by checking at the time of reading or writing at least one or more of sectors which are likely to become defective in the front, back, left and right of the defective sector, for example, as shown in FIG. DOS FAT
In an important area such as the area 10 and the root directory area 11 where reading and writing are always performed, it becomes possible to prevent sudden reading and writing, thereby improving the reliability of the optical disc.

Next, an embodiment of the invention described in claim 4 will be described. When an optical disc that has been used once for certification and replacement processing is certified and used again, the certifying operation of erasing, writing, and verifying all takes time. Therefore, in the present embodiment, when attempting to certify an optical disc that is in use or has been used again, the defective sectors that have been recorded are grouped together, and the sectors before and after in the circumferential direction and the sectors to the left and right in the radial direction become defective sectors. It is determined whether or not there is a defective sector, and a simple certify operation is added to the above-described operation in the case of a defective sector.

In this way, the same effect as the certify operation can be obtained by reading the data of the sectors before and after the defective sector which has already been registered and checking the event in which the error correction has occurred. If there is a sector that has already been erased, the certification operation for that part may be performed.

As described above, when an optical disc used for certification and replacement is used again for certification, the defective sectors registered in PDL5 and SDL9 as a whole are re-registered in PDL9, and further, If a large number of events are read by reading the patterns written in sectors that are likely to be defective sectors in the front, rear, left, and right, and if there are a large number of them, then P is determined as a defective sector.
By additionally registering in DL9, the time can be shortened as compared with the certifying operation of erasing, writing and verifying again.

Next, an embodiment of the invention described in claim 5 will be described. Conventionally, certifying is performed in the same pattern over the front surface of the disc. This pattern is
Various patterns are possible. For example, what is called 8T is good at detecting relatively long errors, but can be missed in the case of small errors or more than it really is. On the other hand, what is called 3T is excellent in finding a small error, but a large error may be missed or less than the actual error. The reason is that whether or not an error occurs is due to a delicate position of a signal obtained from the optical disc, and a delicate error may be overlooked in the same pattern.

Therefore, in the present embodiment, the specific pattern is write-verified, and if a defective sector is detected, it is determined to be a defective sector, and when the information is recorded, the first defect occurs. The second specific pattern is written and read in the sectors on the front and rear in the circumferential direction and on the left and right in the radial direction, and it is determined from the error correction code whether or not the sector is a defective sector. If the sector is a defective sector, the first time and the second time are combined. The alternation process is performed by performing the operation of registering the information by using the above.

Specifically, in the first certification, the entire pattern is searched for a relatively average error to find a defective sector. In the second time, the sectors before and after and to the left and right of the defective sector are certified with a pattern for searching for a small error to search for the defective sector. There is no need to limit this pattern, and it is sufficient to select a pattern having each characteristic. In addition, the definition of a bad sector is as follows:
There is a guideline that M (sector mark) is not recognized and that the data field has a defect of 3 bytes or more is applicable.

As described above, by recertifying the sectors which become defective in the front, rear, left, and right in the future in a pattern different from the pattern obtained by certifying the whole, the same effect can be obtained earlier than certifying twice. Moreover, it is possible to shorten the time required for the replacement process by first removing the sectors that are likely to become defective in the front, rear, left and right. In this case, the definition of the defective sector may be strict.

[0038]

According to the first aspect of the present invention, the information of the defective sector is read, the specific patterns of the sectors before and after in the circumferential direction and the left and right in the radial direction of the defective sector are read, and it is judged from the error correction code whether the sector is a defective sector. , If it is a defective sector, a replacement sector is determined, the information of the defective sector is re-recorded in the replacement sector, and the replacement processing is performed by adding the operation of registering the information of the defective sector and the replacement sector. By checking the sectors which are likely to become defective in the front, back, left and right of the defective sector in this manner, sudden reading and writing cannot be stopped, and the reliability of the optical disk can be improved.

According to the invention of claim 2, in the invention of claim 1, not only the specific pattern but also various patterns written by the user are used to determine the defective sector. By more intensely checking the sectors that are likely to become defective in the front, back, left, and right of the defective sector, sudden reading and writing cannot be stopped, and the reliability of the optical disk can be improved.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the time when it is determined whether the sectors to the front and rear in the circumferential direction and to the left and right in the radial direction of the defective sector are defective sectors. Since this is done when reading or writing one or more of the sectors in the front-back direction in the circumferential direction and in the left-right direction in the radial direction, at least the sectors that are likely to become defective in the front-back and left-right directions of the defective sector in this way. By checking one or more when reading or writing, for example, it becomes possible to prevent sudden reading and writing in an important area that is always read and written, such as the DOS FAT area and root directory area, and improve the reliability of the optical disc. It is possible.

According to the fourth aspect of the present invention, when trying to certify an in-use or used optical disk again, the defective sectors that have been recorded are grouped together, and the sectors in the front and rear in the circumferential direction and the sectors on the left and right in the radial direction are defective. It is judged whether or not it is a sector, and in the case of a defective sector, a simple certify operation is added to the above-mentioned operation. Therefore, once certify and perform the alternation process, the used optical disk is certified and used again. In this case, the defective sectors registered in the PDL and SDL as a whole are re-registered in the PDL, and the patterns written in the sectors that are likely to become defective in the front, back, left, and right of the defective sector are read to correct the error. If the number of events to be recorded is large and the number is large, it can be re-registered by additionally registering it in the PDL , In which it is possible to reduce the erase, write, time reduction in comparison with the certifying operation to be verified.

According to a fifth aspect of the present invention, if a specific pattern is write-verified and a defective sector is detected, it is determined to be a defective sector, and when the information is recorded, the first defect occurs. The second specific pattern is written in and read from the sectors on the front and rear in the circumferential direction and on the left and right in the radial direction, and it is determined from the error correction code whether or not the sector is a defective sector. If the sector is a defective sector, the first and second times are determined. Since the alternation process is performed by performing the operation of registering the information together, by recertifying the sectors that will become defective in the front, back, left, and right in the future in a pattern different from the pattern in which the whole is certified,
The same effect can be obtained faster than certifying twice, and the time for the replacement process can be shortened by first removing sectors that are likely to become defective in the front, rear, left, and right in the future.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing contents created in one sector.

FIG. 2 is an explanatory diagram showing a state in a data field.

FIG. 3 is an explanatory diagram showing a relationship between the number of tracks and a radius with respect to each area in the optical disc.

FIG. 4 is an explanatory diagram showing contents in a data zone.

FIG. 5 is an explanatory diagram showing each part area in DOS.

Claims (5)

[Claims] 1. Information of a defective sector is read, specific patterns of sectors in the front and rear in the circumferential direction and left and right in the radial direction of the defective sector are read, and it is judged from the error correction code whether or not the sector is a defective sector. Determine the replacement sector,
A method for determining a defective sector of an optical disk, characterized in that the information of the defective sector is re-recorded in the alternate sector, and an alternation process is performed by adding an operation of registering information of the defective sector and the alternate sector. 2. The method of determining a defective sector of an optical disk according to claim 1, wherein not only the specific pattern but also various patterns written by the user are used to determine the defective sector. 3. The time to judge whether the sectors before and after the bad sector in the circumferential direction and the left and right in the radial direction are defective sectors is one or more of the sectors before and after the circumferential direction and the left and right in the radial direction of the bad sector. 3. The method for determining a defective sector of an optical disk according to claim 1, wherein the method is performed when reading and writing. 4. When attempting to certify a used or used optical disc again, the recorded defective sectors are collected and whether the defective sectors are located in the front and rear in the circumferential direction and in the left and right in the radial direction. Judge,
A method for determining a defective sector of an optical disk, characterized in that a simple certify operation is performed in addition to the above-mentioned operation in the case of a defective sector. 5. A write-verify of a specific pattern is performed,
If a defective sector is detected, it is determined to be a defective sector, and at the time of certifying that information is recorded, a second specific pattern is formed on the sectors in the front and rear in the circumferential direction and the sectors on the left and right in the radial direction of the first defective sector. Alternate processing is performed by writing and reading the data to determine whether or not the sector is a bad sector from the error correction code, and if the sector is a bad sector, register the information by combining the first and second times. And a method for determining a defective sector of an optical disc.