KR20000025021A - Method for detecting recording/reproducing location - Google Patents

Abstract

PURPOSE: A method for detecting a recording/reproducing location is provided to prevent an error of recording and reproducing data at a faulty location by exactly searching a physical sector number corresponding to a logical sector number transferred from a host. CONSTITUTION: A method for detecting a recording/reproducing location comprises the steps of: obtaining a zone, in which a logical sector number is changed, when the logical sector number is input; obtaining an option(zone) corresponding to the obtained zone; adding a start physical sector number of a data region to the logical sector number to then add the obtained option(zone) to the added result so as to obtain a temporary physical sector number; obtaining the number of registered defective sectors, which have a value less than the temporary physical sector number, in a zone, in which the temporary physical sector number belongs; and obtaining a final physical sector number by adding the obtained number of the registered defective sectors to the temporary physical sector number.

Description

Method for detecting recording / playback position of optical record carrier

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rewritable optical recording medium system, and more particularly to finding a physical sector number (PSN) assigned to an actual optical recording medium from a logical sector number (LSN) assigned only to user data. A recording / reproducing position detection method of a recording medium.

In general, optical recording media are largely divided into three types: read-only ROM, write-once worm type, and rewritable rewritable type. Lose.

Here, the ROM type optical recording medium includes a compact disc read only memory (CD-ROM) and a digital versatile disc read only memory (DVD-ROM), and a worm type optical recording medium is written once. Recordable Compact Discs (CD-Rs) and Recordable Digital Versatile Discs (DVD-Rs).

In addition, freely and repeatedly rewritable discs include a rewritable compact disc (CD-RW) and a rewritable digital versatile disc (DVD-RAM, DVD-RW).

On the other hand, in the case of a rewritable optical recording medium, the recording / reproducing operation of information is repeatedly performed due to the use characteristics thereof, so that the mixing ratio of the mixture constituting the recording layer formed for recording information on the optical recording medium is initially mixed. It becomes different from the ratio and loses its characteristics, resulting in an error in recording / reproducing information.

This phenomenon is called deterioration, and the deteriorated area appears as a defect area when the format, recording, and reproducing command of the optical recording medium is executed.

In addition to the deterioration phenomenon, defect areas of the rewritable optical recording medium may be generated due to scratches on the surface, dust such as dust, errors in production, and the like.

Therefore, in order to prevent data from being recorded / reproduced in the defect area formed due to the above reasons, it is necessary to manage the defect area.

To this end, a general rewritable optical recording medium, that is, a rewritable optical disc, has a defect management area in a lead-in area and a lead-out area as shown in FIG. Area (hereinafter referred to as DMA) is used to manage the defective area of the optical recording medium. The data area is divided and managed by zones, and each zone is divided into a user area in which actual data is recorded and a spare area for use when a defect occurs in the user area. As shown in FIG. 2, a guard area is allocated between zones to distinguish them.

The DMA includes a PDL (Primary Defect List), which means a major defect data storage unit, and a SDL (Secondary Defect List), which means a defective data storage unit.

In general, the PDL stores entries created during the disc creation process and entries of all defective sectors identified during formatting, ie, initializing and re-initializing the disc. In addition, the SDL is listed in units of blocks, and stores entries of defect areas that occur after the format or defect areas that cannot be stored in the PDL during the format.

In such an optical disk, each sector has an LSN and a PSN, where the LSN is a value assigned only to a user area in which actual data is recorded, and the PSN is a value indicating a physical position on the disk assigned to each sector of the disk during the disc manufacturing process.

Therefore, if there are no defects in the data area at all, as shown in Fig. 3A, the PSN is given to all areas, but the LSN is given only to the user area in which actual data is recorded.

On the other hand, if there is a defect in the data area, the defective areas (i.e., defective sectors or defective blocks) in the data area are replaced with a normal area. As a replacement method, a slipping replacement method and a linear replacement method are usually performed. There is a way.

The sleeping replacement method is applied when a defective area is registered in the PDL. If a defective sector listed in the PDL exists in a user area in which actual data is recorded, as shown in FIG. The sector is skipped and instead replaced by the normal sector following the defective sector to record the data. At this time, the PSN remains in the defect sectors listed in the PDL, but there is no LSN because data is not recorded or reproduced in the defect sectors. Instead, the LSN is allocated to the spare area by the number of defective sectors. Here, the spare area to which the LSN is assigned becomes a user area by formatting.

In addition, the linear replacement method is applied when the defect area is registered in the SDL. If a defect block listed in the SDL exists in the user area or the spare area as shown in FIG. 3C, the linear replacement method is applied to the spare area. Data is recorded by being replaced with a replacement area of the allocated block unit. At this time, the PSNs allocated to the sectors of the defective block remain as they are, but the LSN moves together with the data to the replacement block.

4 is a block diagram illustrating an example of a general optical disc recording / reproducing apparatus, comprising: an optical pickup for recording and reproducing data on an optical disc, a pickup transfer unit for transferring the optical pickup, and processing input data to the optical pickup; And a data processing unit, an interface, a microcomputer for controlling them, and the like, and a host is connected to an interface of the optical disc recording / reproducing apparatus so that commands and data are transmitted to each other. Here, the host is a kind of personal computer (PC), in which the optical disc recording apparatus is supported by the PC.

When data to be recorded in FIG. 4 configured as described above is generated, the host sends a recording command to the optical disc recording apparatus. The write command includes a logical block address (LBA) that specifies a write location and a transfer length that indicates the size of the data. The host then sends the data to be recorded to the optical disc recording / reproducing apparatus. Here, LBA has the same meaning as LSN.

When the data to be recorded on the optical disk is transmitted from the host, the optical disc recording / reproducing apparatus finds the corresponding starting PSN from the starting LBA and starts recording the transmitted data. This is because the LBA is a value given only to the area where the actual data is recorded, not the actual position on the disk.

At this time, the optical disc recording / reproducing apparatus does not record data in the defective area by using the PDL and the SDL which are information indicating a defect of the optical disc.

That is, the physical sector recorded in the PDL is recorded while skipping, and the physical block recorded in the SDL is recorded by replacing with a replacement block allocated to the spare area.

In addition, if there are defective blocks or blocks with many errors that are not listed in the SDL during recording or playback, the blocks are regarded as defective blocks for data protection, and the replacement block of the spare area is found to rewrite the data of the defective blocks. The position information of the defective block is then registered in the SDL entry.

In this way, if there is a defective area at the time of data recording or reproducing, no data is recorded at that position, so that the LSN is not assigned to the defective area.

Therefore, it is very important to find the exact PSN corresponding to the LBA transmitted from the host. If the exact PSN is not found, data is recorded or played back at the wrong position.

However, if a defect exists, it is difficult to find the actual starting PSN corresponding to the starting LBA since there is no LSN at the defective position. In particular, when the spare area is divided into zones, it becomes more difficult. This is because the LSN is not allocated to the spare area and the protected area.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a recording / reproducing position detection method of an optical recording medium for accurately finding a PSN corresponding to an LSN transmitted by a host using a table. .

1 is a view showing the structure of a typical optical disk

FIG. 2 illustrates a detailed structure of the data area of FIG. 1. FIG.

3A shows the relationship between the PSN and the LSN in the absence of a defect

3b is a diagram illustrating a general sleeping replacement method and a relationship between PSN and LSN at this time

3c is a diagram illustrating a general linear replacement method and a relationship between PSN and LSN at this time

4 is a block diagram of a general optical disc recording / reproducing apparatus;

5 is an operation flowchart of a recording / reproducing position detecting method of an optical recording medium according to the present invention.

6 is a table showing a physical zone area in a recording / reproducing position detection method of an optical record carrier according to the present invention.

7 is a table for finding a zone to which a starting LSN belongs in a method for detecting a recording / reproducing position of an optical recording medium according to the present invention.

8 is an offset table for finding a PSN in a recording / reproducing position detection method of an optical recording medium according to the present invention.

9A shows the structure of a general data unit 1

FIG. 9B illustrates the structure of the data ID of FIG. 9A

In the recording / reproducing position detection method of the optical recording medium according to the present invention for achieving the above object, if the LSN is input from the host transmitting the LSN attached to the data, if the recording / reproducing of the data is required to belong to the LSN Obtaining a zone, obtaining an offset [zone] corresponding to the zone obtained in the above step, obtaining a temporary PSN by adding the starting PSN of the data area to the LSN, and then adding the offset [zone] obtained in the step; And obtaining the number of registered defective sectors having a value smaller than the temporary PSN in the zone to which the temporary PSN belongs to obtaining the final PSN in addition to the temporary PSN.

If the input LSN is a starting LSN and not a multiple of an ECC block unit, the starting LSN is a multiple of an ECC block unit.

The step of finding the zone may be a function of finding a zone to which the LSN belongs by using a table after mapping a table in advance so as to distinguish each zone according to the LSN.

The calculating of the offset [zone] may be performed by mapping the number of sectors corresponding to the spare area and the protection area to a table for each zone, and then applying the zone found in the step to the table to obtain an offset [zone].

The step of obtaining the final physical sector number is characterized in that if the starting PSN is a defective sector number registered in the PDL, the starting PSN is increased by one to be the final starting PSN.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the present invention, in order to find the starting PSN corresponding to the starting LBA transmitted by the host, the table shown in FIGS. 6 to 8 is pre-mapped.

For example, assuming that the PSN representing the physical zone is A, C, F, ... as in FIG. 2, and the user area of each zone is A, D, G, ..., FIG. 7 is a table for identifying physical zones, FIG. 7 is a table for finding a zone to which a starting LBA belongs, and FIG. 8 is an offset table for recording the number of sectors corresponding to a spare area and a protection area between zones and zones. Here, according to the specification, since the start PSN of the data area of the optical disc is 31000h, if there is no defect, the position A in Fig. 2 is PSN 31000h and LSN 00000h.

Fig. 5 is an operation flowchart of the present invention for finding the recording / reproducing position of the optical recording medium using such a table. When the data to be recorded on the optical disk is generated or the recorded contents are reproduced, the host first records or starts the LBA. It is included in the reproduction command and transmitted to the optical disc recording / reproducing apparatus (step 501).

When the start LBA is input from the host, the optical disc recording / reproducing apparatus determines whether the start LBA is a multiple of 16 (step 502). If the starting LBA is a multiple of 16, the process proceeds directly to step 504. If it is determined that the starting LBA is not a multiple of 16, the starting LBA is converted to a multiple of 16 that is not greater than the starting LBA, and the process proceeds to step 504 (step 503). For example, if the starting LBA is 33, convert it to 32.

This means that recording / playback to the optical disc is made in units of Error Correction Code (ECC) blocks, or 16 sectors, which the host does not know about and generates a starting LBA, so matching the starting LBA with the first sector number of the ECC block. To do that.

In step 504, the starting LBA, which is a multiple of 16, is applied to the table as shown in FIG. 7 to find the zone to which the starting LBA belongs.

That is, if the starting LBA (= LSN) is between 0 and L_zone [0], the starting LBA is determined to belong to zone 0, and the starting LBA (= LSN) is between L_zone [0] and L_zone [1]. Between], the starting LBA is determined to belong to zone 1.

If the zone to which the starting LBA belongs is determined by the above process, the zone is applied to the table of FIG. 8 to find an offset [zone] (step 505). This is because the spare area and the protection area between each zone are not given an LSN. If the zone determined in step 504 is determined to be zone 1, an offset value corresponding to zone 1 may be read from the table of FIG. 8. The offset [zone] value is the number of sectors corresponding to the spare area and the protection area between the zone and the zone.

When the offset value of the corresponding zone is determined in step 505, a data field number (DFN) assigned to each sector is obtained (step 506). That is, DFN can be obtained as shown in Equation 1 below.

DFN = start LBA + X

Here, X is a starting PSN value of the data area, and if there is no defect, the starting PSN of the data area is 31000h.

That is, each sector is divided into a header field, a mirror field, and a recording field, and the recording field includes a data field, and the data recorded in the data field is processed by a signal. Follow the steps to call Data Unit 1, Data Unit 2, and Data Unit 3. As shown in FIG. 9A, the data unit 1 includes a data ID area and a main data area in which actual data is recorded. The data ID is composed of data field information and DFN as shown in FIG. 9B. The DFN becomes the starting PSN value of the LSN + data region as shown in Equation 1, but like the LSN, it is not given to the spare region and the protection region.

Therefore, the DFN is not the starting PSN to record or play the actual data. That is, the number of spare areas and protected area sectors of the corresponding zone to which the DFN has not been allocated should be considered. For this purpose, in step 507, the temporary starting PSN (Pre_PSN) is added to the DFN by adding the offset value of the corresponding zone obtained in step 505. Obtain

Then, the offset_PDL is obtained (step 508), and the offset_PDL is the number of values smaller than Pre_PSN among defects in the corresponding zone by the table of FIG. 6 in the PDL list. For example, if Pre_PSN corresponds to zone 1 and its value is 45000h, and the number of defective sectors listed in the PDL is 10 in zone 1 and the number of defective sectors less than 45000h in the zone of zone 1 is offset_PDL Becomes five. If the number of defective sectors listed in the PDL in the zone 1 zone smaller than 45000h is offset_PDL is zero. That is, since the LSN is not assigned to the defective sectors listed in the PDL, but the PSN is present, the offset_PDL should also be considered in the starting PSN.

Therefore, in step 509, the start PSN is obtained by adding the offset_PDL to Pre_PSN. Then, it is determined whether the starting PSN is in the PDL (step 510).

In this case, if the starting PSN is not in the PDL, the starting PSN obtained in step 509 becomes the final starting PSN to record or play the actual data. If the starting PSN is in the PDL, data cannot be written or read in this part, so that 1 is added to the starting PSN. A final starting PSN is taken (step 511). If the starting PSN of the increased position is also in the PDL, the starting PSN is increased by one and the process is repeated until the starting PSN is not in the PDL.

As described above, according to the method of detecting the recording / reproducing position of the optical recording medium according to the present invention, a table for finding a zone corresponding to a starting LSN, a number of spare areas between each zone and the zone, and the number of sectors corresponding to the protection area are recorded. By mapping the offset table in advance and accurately finding the starting PSN corresponding to the starting LSN transmitted from the host using the tables, an error of recording or reproducing data at the wrong position does not occur. In addition, even if a spare area is allocated for each zone, the PSN can be easily found by the table.

Claims (6)

A control unit for transmitting a logical sector number assigned to the data and an optical recording medium recording / reproducing apparatus for recording or reproducing data at a physical sector number corresponding to the logical sector number transmitted by the control unit, if data recording / reproducing is necessary. In the recording / playback position detection method of the optical recording medium used, Obtaining a zone to which the logical sector number belongs when the logical sector number is input; Obtaining an offset [zone] corresponding to the zone obtained in the above step; Obtaining a temporary physical sector number by adding the starting physical sector number of the data area to the logical sector number and adding the offset [zone] obtained in the above step; Obtaining a number of registered defective sectors having a value smaller than the temporary physical sector number in the zone to which the temporary physical sector number belongs, and obtaining a final physical sector number in addition to the temporary physical sector number. Method for detecting recording / playback position of recording medium. The recording / reproducing position detection of the optical recording medium according to claim 1, wherein if the input logical sector number is a starting logical sector number and not a multiple of ECC block units, the starting logical sector number is a multiple of ECC block units. Way. The method of claim 1, wherein the step of finding the zone is And mapping a table in advance so as to distinguish each zone according to a logical sector number, and then finding a zone to which the logical sector number belongs by using the table. The method of claim 1, wherein the obtaining of the offset [zone] A method of detecting a recording / reproducing position of an optical recording medium, wherein the number of sectors corresponding to a spare area and a protection area is mapped to a table for each zone, and then an offset [zone] is obtained by applying the zone found in the step to the table. . 2. The method of claim 1, wherein obtaining the final physical sector number is And if the starting physical sector number is a registered defective sector number, the starting physical sector number is increased by one to be the final starting physical sector number. 6. A method according to claim 5, wherein the defective sector is a defective sector stored in a main defect data storage (PDL).