JPH04172661A - Managing method for defect of memory medium - Google Patents

Abstract

PURPOSE:To easily convert to a physical address by obtaining an accumulating number corresponding to a logical address smaller than and nearest to the logical address to be converted by referring to a special table, and adding the logical address to be converted to the number to obtain the physical address. CONSTITUTION:A table in which an accumulating number of defective sectors detected at the time of initializing up to a logical address is corresponded to the logical address of next sector of the detector detected at the time of initializing, is formed. Conversion from the logical address to a physical address is conducted by referring to the table, the number corresponding to the logical address smaller than the logical address to be converted and nearest to the logical address is obtained, and the value obtained by adding the physical address to be converted to the number is set as the physical address. Thus, the logical address can be easily converted to the physical address.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a storage medium defect management method for converting a logical address into a physical address when a defect occurs in a storage medium.

Conventional technology The storage area of a storage medium such as an optical disk consists of a user area used by the user of the host system, a spare area for replacing bad sectors other than initial bad sectors that are bad sectors shipped from optical disks, and a management area for managing the replaced information. Sector slipping defect management (defect management) is used to manage these bad sectors.
Sectors! ipping Defect
management (hereinafter referred to as SDM) and linear replacement defect management (hereinafter referred to as SDM) and linear replacement defect management (hereinafter referred to as SDM).
t Management (hereinafter referred to as LDM).

SDM is a method that removes bad sectors before a user uses an optical disc for the first time, and it erases and writes certification to the trunk number and sector number that are physically managed on the optical disc. , verify or other means to detect an initial defective sector, and remove the defective sector and spare area (operation to complement the defective sector), and assign a logical number for access from the host system.

LDM is a method for removing bad sectors when they subsequently occur on an optical disk that has been subjected to SDM.

An example of such defect management will be explained using FIGS. 14 and 15.

Figures 14 and 15 are currently ISO (International Standardization Organization #1)
In this paper, we present an algorithm for defect management of full R, AM (erasable and rewriteable) optical disks, which is under consideration in Section I). FIG. 14 shows the SDMed state.

In FIG. 14, the numerical values in the areas indicated by physical track numbers and sector numbers indicate logical numbers. For example, physically track number 2. The position of sector number 1 is
Shown as 25 in logical number.

Track number 2. If sector number 2 is a bad sector (indicated by an x), no logical number is assigned to this sector and the next track number 2. Logical number 2 in sector number 3
Assign 6.゛Figure 15 shows the state of LDM. In FIG. 15, R1 of track number 5 and sector number 7, which became defective after SDM, is located in the spare area with trunk number 8. It is stored with the logical number 65 attached to the sector number O. Therefore, when accessed from the higher level system with logical number 65, track number 8. Sector number 0 will be accessed.

Next, track number 7. When allocating the bad sector of R2 with sector number 7 to the spare area, trunk number 8 of the spare area. Since sector number l is a bad sector, this sector is not used, and logical number 89 is assigned to the next track number 8 and sector number 2.

In order to carry out such defect management, it is necessary to convert a logical number (logical address) into a physical number (physical address). For this reason, conventionally when performing SDM, the defect area table shown in FIG.
When performing M, the replacement table shown in FIG. 17 is used to convert a logical address to a physical address.

FIG. 16 is a table in which the physical addresses of defective sectors that were found to be defective at initialization are arranged in ascending order, and FIG. 17 is a table that shows the physical addresses of defective sectors that were found to be defective at initialization and the spare area in which this defective sector has been replaced. This is a table in which physical addresses of alternative sectors are arranged in ascending order. To convert a logical address to a physical address using these two tables, first, when a logical address is given, compare the defect area tables starting from the first one and calculate how many defects exist up to that logical address. Search and add that value to the logical address to find the physical address. At the same time, the replacement table is also searched, taking into account whether or not the physical address has been replaced.

Problem to be Solved by the Invention In read/write operations using such a conversion method, when a start logical address and the number of transfer blocks are given, it is necessary to perform the above conversion within the range of the number of transfer blocks. . Furthermore, when the user area is divided into zones, the number of spare areas for each zone and defects existing within the spare areas must also be taken into consideration, making the conversion procedure extremely complicated.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a storage medium defect management method that easily converts a logical address into a physical address.

Means for Solving the Problems In order to achieve the above object, the storage medium defect management method of the present invention includes a data area consisting of sectors for storing data, and defects occurring in this data area after initialization after this data area. One zone is formed with a reserved I area provided with a sector replacement sector, this zone is arranged in one or more classes to form a storage area, and physical addresses are numbered in ascending order to all these sectors, A storage medium defect management method in which logical addresses are numbered in ascending order, skipping initial defective sectors and spare areas, and the logical address of the sector next to the defective sector at initialization is initialized up to that logical address. When converting a logical address to a physical address, create a list that corresponds to the cumulative number of defective sectors, and refer to the list to convert a logical address to a physical address. The cumulative number is calculated, and the value obtained by adding the logical address to be converted to the cumulative number is used as the physical address. Further, when a defect is detected in a sector of the spare area at the time of initialization, the cumulative number includes the number of the defective sector.

Effect: With the above configuration, the physical address can be obtained by referring to the table to find the cumulative number corresponding to the logical address smaller and closest to the logical address to be converted, and adding the logical address to be converted to this cumulative number. Therefore, it can be easily converted to a physical address. Furthermore, when an initialization defect is detected in a sector of the spare area, the number of defective sectors can be included in the cumulative number. Even if the number of sectors in the spare area is set to the sum of the numbers, the conversion to physical addresses after this spare area can be performed in the same way as when no defective sectors occur in the spare area. As a result, all of the planned number of sectors in this pre-m area can be used as replacement sectors assuming that no defective sectors will occur.

Example Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of a defect management table used in an embodiment of the present invention. This defect management table consists of LBA (Logical Block Add
ress: logical address) table, logical/physical conversion table, and replacement table.
Together, these blocks are called a defect management block, and these blocks are arranged in ascending order of logical addresses (LBA).

In this table, the LBA table represents the next sector of the slipped sector or the sector being replaced by a logical address.

The logical/physical conversion table represents how many defect areas are present up to the above logical address.

The replacement table is for distinguishing whether the above-mentioned logical address is a slipped sector or a replaced sector, and in the case of replacement, the replacement physical address is entered.

FIG. 2 shows a zoning table. This diagram shows the number of zones N when the user area is divided into zones, the number of user areas per zone 02 the number of spare areas per zone m
is set.

FIG. 3 shows the zone pointer table.

In this table, the block t of the defect management table corresponding to the head of the zone when the zone is divided and the last registered block distance are stored.

FIG. 4 shows a spare area table representing the usage status of the spare area. Here, the usage status (used, usable, defective) of the spare area of the first zone is expressed in bytes.

FIG. 5 shows a spare area pointer table pointing to the beginning of the spare area of the fth zone of the spare area table.

Next, as a specific example, defect management using the above table will be explained using FIG. 6.

Number of zone divisions 2. 100 user areas per zone,
The number of spare areas for each zone is 10. In addition, as shown in Figure 6, there are two swamping areas in zone 0 (sectors before logical addresses 14 and 32), two replacement areas (logical addresses 50 and 74), and a spare area in zone O. Assume that there are two slipping areas. If this situation is represented in the defect management table of FIG. 1, it will be as shown in FIG. 7. (however,
The replacement value at the time of slipping is FFFFFF. ) In Figure 6, the numbers in squares are logical addresses, the numbers in parentheses are physical addresses, × is bad sectors, R1,
R2 indicates the replaced sector, zone O
Alternative sectors for R1 at logical address 50 and R4 at logical address 74 are set in the spare area. Furthermore, as shown in the figure, there is a slipping area indicated by two x's in this spare area. The number of sectors in this spare area is 10, but since two of them are defective sectors, only eight remaining sectors can be used as alternative sectors.

Therefore, the number of sectors is set to 12, and the number of alternative sectors that can be effectively used is set to 10, which is the same number as when no defective sector occurs. As a result, the value of the logical/physical conversion address of the logical address 100 of block number 5 becomes 14, as shown in FIG. This means that the number of x's up to logical address 99 is 2, and the number of alternative sectors in the spare area is 10. The number of ×'s in the spare area is 2, making a total of 14.

FIG. 8 shows a zone pointer table, in which the first block number of zone O (00), the first block It of zone 1 (05), and the last registered block group (05) are set.

FIG. 9 shows a spare area pointer table, in which an offset value from the beginning of the spare area table is set. The offset value of zone O is 0 bytes, and the offset value of zone I is 12 bytes. This is because the spare area of zone O includes two defective sectors, so 12 sectors were taken.

FIG. 10 shows the spare area table. The spare area in zone O represents the state of the spare area in FIG.

Next, the procedure for converting a logical address to a physical address will be explained using the above table.

FIG. 11 is a flowchart of the conversion procedure. Assuming that 40 is specified as the logical address (step 1), that logical address is included in zone O (step 2).

Next, find defect management blocks O and 5 from the zone pointer table (step 3), compare the LBA table values in blocks 0 to 5 with the logical address (40), and find the nearest block floor 2 smaller than 40 (step 3). At this time, the logical/physical conversion table value 2 of block block 2 is calculated (step 7), and the logical address (
40), the physical address -40+
2-42 is determined (step 9.10), and if the specified logical address has been replaced (step 6), its physical address is determined from the replacement table (step 8).

By using the defect management table in this way, logical/physical conversion becomes possible easily.

Next, the read operation procedure will be explained using the read operation flow diagram of FIG. 12.

When the read start logical block address and transfer block are specified, the start logical address is converted into a physical address (step 11). When a swamping area is included in the transfer block from there (step 12
), set the number of sectors that can be read continuously up to the slipping area from the defect management table (
Step 13). Furthermore, the number of consecutive slippings (defects) is set (step 14). Based on this information, a physical address read is performed (step 18), that is, after reading for the sectors set in step 13, the read operation for the sectors set in step 14 is skipped. Check whether the read is finished (step 19), and if it is not finished, update the start logical address and transfer block and repeat the above operation. Similarly, if a replacement area exists (step 15), read the replacement area. Set the number of sectors that can be read continuously up to (Step 1)
6) Also, set an alternative physical address for the replace spare area from the defect management table (step 17), and repeat the above operations.

By the above procedure, the read operation can be easily performed even when a slipping area and a replacement area coexist.

Next, the write operation procedure will be explained using the write operation flow diagram of FIG.

Since the write operation is almost the same as the read operation procedure, the different points will be explained. In step 28, an alternative sector is searched for when refining to write fails (step 29). This uses the spare area pointer value corresponding to the number of zones of the sector in which writing failed to obtain the offset value from the spare area table, and searches for the position of the usable sector in the spare area table.

For example, when write verification fails in zone O and a replacement sector is searched, the spare area pointer value corresponding to zone O in FIG. 9 is 00, and The offset value will be 0.

If you search in order from there, you will find that the third usable area is 00. Therefore, the alternative physical address is
102 from the first physical address 102 of the spare area in zone 0 and this third address (counting 2 as 0, 1, 2) 2
+ 2 = 104. In addition, even if there is a slipping area in the spare area, you can easily search for it using the same procedure.
Can be converted.

Effects of the Invention As is clear from the above description, the present invention can easily convert a logical address to a physical address even when there is a defective sector by using a defect management table.

[Brief explanation of the drawing]

Figure 1 shows the format of the defect↓ control chart used in the embodiment of the present invention, Figure 2 shows the format of the zone division team 4°, Figure 3 shows the format of the zone pointer iron bull, and Figure 4 shows the space area format. ↓ Figure 5 is a diagram showing a concrete example of arranging addresses in the spare area pointer table's 6th zone area and space area, Figure 7 is a diagram showing a concrete example in the defect management table. Figure 8 is a diagram with concrete examples written in the zone pointer table, Figure 9 is a diagram with concrete examples written in the spare area pointer table, Figure 1O is a diagram with concrete examples written in the spare area table, and Figure 8 is a diagram with concrete examples written in the spare area pointer table. Figure 11 is a flow diagram of converting a logical address to a physical address, Figure 12 is a flow diagram of a read operation,
Fig. 13 is a write operation flow diagram, Figs. 14 and 15 are explanatory diagrams for processing defective sectors, Fig. 16 is an explanatory diagram of a conventional defect area table, and Fig. 17 is an explanatory diagram of a conventional replacement area table. . Name of agent: Patent attorney Akira Okaji and two others Figure 1 Tiffect Figure 2 Figure 6 Figure 4 Figure 5 Figure 6 Figure 7! @8 Figure 10 Figure 9 7'-yQ 7'-7, 11th
Figure 12 Figure 13 Figure 14 Sector direction □ × indicates a sector that is not printed. 0-177 in the user area indicates a logical number. Sector direction X in FIG. 15 indicates a non-printing sector. 0-177 in the user area indicates a logical number. R1 and R2 indicate replacement processing. Figure 16 Figure 17

Claims (2)

[Claims] (1) One zone is formed by a data area consisting of sectors that store data and a spare area that is provided with replacement sectors for defective sectors that occur in this data area after initialization after this data area. Storage media defect management that configures a storage area by arranging one or more sectors in order, assigns physical addresses to all of these sectors in ascending order, and assigns logical addresses in ascending order, skipping initial defective sectors and spare areas. In this method, a list is created in which the logical address of the sector next to the sector detected during initialization corresponds to the cumulative number of defective sectors detected during initialization up to that logical address, and the physical For conversion to an address, refer to the table above to find the cumulative number corresponding to the logical address smaller and closest to the logical address to be converted, and store the value obtained by adding the logical address to be converted to this cumulative number as a physical address. Media defect management method. (2) The storage medium defect management method according to claim 1, wherein when a defect is detected in a sector of the spare area at the time of initialization, the cumulative number also includes the number of the defective sector. .