JPH04176058A - Memory medium - Google Patents

Abstract

PURPOSE:To perform the processing of a defective sector adequately when a RAM region and a ROM region are mixed by providing spare memory regions wherein the contents which are stored in a defective recording function parts occurring in a readable and writable memory region and a read-only memory region are stored. CONSTITUTION:A fan-type read-only memory region (ROM region) 2 is provided in an optical disk, and a readable and writable region (RAM region) 1 is provided in the remaining region. In the RAM region 1, two concentric partial rings are provided as spare regions 3. In the spare regions 3, the contents which are to be stored in the defective sectors of the RAM region 1 and the ROM region 2 are stored. When the RAM region 1 and the ROM region 2 are mixed in this way, writing for inspection cannot be performed in the ROM region 2. However, error correcting codes are included as the data in the sector, or code regions (parities) are included in another sectors. Therefore, the place of the sector where the error is present can be judged, and the correction can be performed. In this way, the defective sector wherein the RAM region and the ROM region are mixed can be adequately processed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a storage medium having a read/write storage area and a read-only storage area.

Conventional technology In order to provide users with inexpensive known data, manufacturers of memory such as optical disks have developed a ROM area that is read-only and cannot be rewritten, and a ROM area that is readable and rewritable.
The development of optical discs that mix A, M, and 6M areas is underway. Optical disk manufacturers store existing data in the ROMeff area when shipping optical disks, for example,
Map information Provides basic information such as the layout of one store, and is stored in a RAM area that can be rewritten by each user.
When saving updated information such as additions or changes to basic parts and saving the latest information to an optical disk, the ROM area for storing existing data and the RAM area for storing updated data are stored on one optical disk. This will streamline information management and improve the efficiency of information access and retrieval.

By the way, the area of an optical disk is a user area used by the user of the host system, and a spare area for replacing sectors that have become defective other than the initial defective sectors that are defective sectors at the time of shipment of the optical disk.

Defect management includes sector slipping, defect management, and a management area that manages the replaced information.
Management (Sector slipping De
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)
ect Management (hereinafter referred to as LDM)
There is.

SDM is a method that removes bad sectors from an optical disc before the user uses it for the first time.Certification: the entire optical disc is erased from the track numbers and sector numbers that are physically managed on the optical disc. , write, verify or other means to detect the initial bad sector and compensate for the bad sector) except for bad sectors and spare areas.
Allocates a logical number for access from the higher-level 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. 13 and 14.

Figures 13 and 14 show algorithms for defect management for full RAM (erasable and rewriteable) optical discs currently under consideration at 150 (International Organization for Standardization). FIG. 13 shows the SDMed state.

In FIG. 13, the numerical values in the 'pM area indicated by the physical track number and sector number indicate logical numbers.

For example, physically trunk number 2. The location of sector number 1 is indicated by logical number 25.

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.

FIG. 14 shows the state of the LDM. In FIG. 14, R1 of track number 5 and sector number 7, which became defective after SDM, is located at trunk number 8. It is stored with a logical number 65 attached to sector number 0. 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. Sector number 7
When allocating R2's failure rate to spare area 3, the trunk number of spare area 3 is 8. Since sector number 1 is a bad sector, this sector is not used and logical number 89 is assigned to the next trunk number 83 and sector number 2.

vRM to be solved by the invention As mentioned above, there is defect management for full RAM, but for RAM 8i area and ROM eT
There is no suitable solution for the case where J area is mixed.

The present invention has been made in view of the above problems, and
It is an object of the present invention to provide a storage medium that can perform defect management when RAM areas and ROM areas coexist.

Means for Solving the Problems In order to achieve the above object, the storage medium of the present invention has a read/write storage area, a read-only storage area, and the content to be stored in the memory function defective portion of both storage areas. It also includes a spare storage area for storing data. Furthermore, if there is a code area in the read-only storage area, logical addresses are not assigned to sectors within this code area. It also includes a readable and writable storage area, a first spare storage area that stores the contents to be stored in a memory function defective part that has occurred in the readable and writable storage area, a read-only storage area, and a read-only storage area. A second preliminary storage area is provided nearby to store the contents to be stored in the storage function defective portion that has occurred in this storage area.

By providing a spare storage area to store the contents to be stored in the defective part that occurs in the read/write storage area and the read-only storage area, the read/write storage area can be written using SDM before being used for the first time. detects an initial bad sector, slips this bad sector and assigns a logical number. Further, for a defective sector generated after this process, a logical number assigned to the defective sector is assigned to a spare storage area using the LDM, and the contents to be stored in the defective sector are stored therein. Furthermore, for read-only storage areas, initial defective sectors cannot be detected by writing or the like, and SDM cannot be used. However, since the information in the sector includes an error correction code or a code area (parity) in another sector, it is possible to determine the location of the sector where an error exists. Therefore, a read-only storage area is assigned a logical number without slipping even if it is a bad sector, and the logical number of this bad sector is assigned to a spare storage area using LDM, and the content to be stored in this bad sector is Store.

In addition, for bad sectors generated after this processing, the logical number assigned to the bad sector is assigned to the spare storage area using LDM in the same way as the read/write storage area, and the contents to be stored in the bad sector are stored here. .

Also, a code area (parity) is stored in the read-only storage area.
When an initial defective sector in that area is detected and complemented (certified), a logical number is not attached to this code area and it is slipped. By not assigning logical numbers in this way, it is possible to delete this code area or use it for another area when manufacturing becomes stable and errors no longer occur in the read-only storage area. Become.

Further, the first spare storage area stores the contents to be stored in the memory function defective part that has occurred in the readable/writable storage area,
The second spare storage area stores the contents to be stored in the memory function defective part that has occurred in the read-only storage area, thereby certifying the read-write storage area and the read-only storage area separately. becomes possible.

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

1 to 3 show a first embodiment of the present invention.

Fig. 1 shows an optical disk provided with a fan-shaped read-only storage area 2 (hereinafter referred to as ROM area) and the remaining area as readable/writable area 1 (hereinafter referred to as RAM area). , two concentric partial rings are provided as a spare area 3. This spare area 3 stores what is planned to be stored in the bad sectors of the RAM file area 1 and the ROM 6i area 2.

FIGS. 2 and 3 are explanatory diagrams that represent FIG. 1 in a two-dimensional manner and perform SDM and LDM as defect management. As shown in FIG. 1, RAM area 1 and ROM 9
When i area 2 is present, there is a problem in detecting initial bad sectors and performing certification to complement the bad sectors.Since writing cannot be written to ROM area 2 for inspection, SDM This is something that cannot be done. However, since the information in the sector includes an error correction code or a code area (parity) in another sector, the location of the sector where the error exists can be determined and correction can be performed. Therefore, in FIG. 2, only RAM iI area 1 is subjected to SDM to slip bad sectors and assigned logical numbers, while ROM area 2 is not slipped and logical numbers are also assigned to bad sectors. However, sectors ROI and RO2, which are bad sectors in ROM area 2, may become unreadable due to deterioration of the optical disk, or when a read command is received from the host system to read other code areas and rescue the bad sectors. If you do this, processing efficiency will deteriorate, so when performing certification in advance, only the bad sectors in the L ROM area 2 are transferred to the spare area 3 with the corrected data in the LDM 4.
Certification is achieved by performing such a process of performing frequent substitutions.

Figure 3 shows that the certified optical disc shown in Figure 2 has a bad sector (R
FIG. 4 is a diagram illustrating a state in which RAI and RA2 are replaced in the spare area 3 by LDM when RAI and RA2) occur.

Next, a second embodiment will be explained using FIGS. 4 and 5. FIG. 4 shows a state in which the partial ring of the spare area 3 is extended to form a complete ring in the sector-shaped ROM area 2 explained in FIG. Figure 5 is a two-dimensional display of Figure 4, showing the SDM, LD
It is an explanatory diagram of performing M. This example also received the same certification as the first example, and then the RAM
If a bad sector occurs in area 1 or ROM area 2, the LD
M allows bad sectors to be stored in the spare area 3.

Next, a third embodiment will be explained using FIGS. 6 and 7. The spare area 3 shown in FIGS. 1 and 4 is RAMq area 1 and R.
Although it was shared with the OMSi area 2, in this embodiment, as shown in FIG.
A spare area 32 for leaning the castle is provided for exclusive use. By doing this, RAM SJI
Since it becomes possible to manage area 1 and ROM area 2 separately, RAM area 1. Area 1 and ROM H area 2 can be certified separately.

For example, when a user uses the optical disc for the first time, the RAM area 1. ROM area 2
Certify together and then re-forge.
When the need for mating arises, the spare area 32 for the ROM area can be left without being erased, and only the other RAM area l can be certified. This improves the processing efficiency of reformatting (certification).
This is an explanatory diagram of a state in which certification is performed on both OM area 2, and then a bad sector occurs in RAM area 1 and LDM processing is performed.6 Next, a fourth embodiment will be described using FIGS. 4 and 8. explain. This embodiment uses the RAM area 1 in FIG. 4 explained in the second embodiment.
．． ROM area 2. In spare area 3, ROM area 2
When a code area 5 (parity) of the ROM exists in the ROM, when certifying the code area 5, the code area 5 is slipped without assigning a logical number as shown in Fig. 8. show. In this way code area 5
By processing this, when the code area 5 is no longer needed later (when the error in ROM area 2 no longer occurs), this code area 5 can be logically and physically deleted during the manufacturing of the optical disk. or can be used in other areas. If a logical number is assigned to code area 5, from the user's perspective, code area 5 will exist, indicating to the user that unnecessary data exists on the optical disc. The defect is to prevent such users from seeing unnecessary things.
It's management.

Further, a fifth embodiment will be explained. Spare area 3 in this embodiment
are the same as shown in Figure 4, and RAMq areas l and R
It is shared with OM area 2. Specific differences from the second embodiment will be explained using FIG. 9. FIG. 9 is a plan view of FIG. 4 to explain how SDM and LDM are performed. In this embodiment, as in the first embodiment, only RAM area 1 is subjected to SDM, bad sectors are slipped and logical numbers are assigned, and ROM fiJ area 2 is not slipped and logical numbers are also assigned to bad sectors. ing. Then, only the defective sector in the ROMjN area 2 is replaced with the corrected data in the spare area 3 by LDM. Here, in this embodiment, sectors in the spare area are removed by the number of bad sectors subjected to SDM in the RAM area 1, and the sectors in the ROM area 2 are
allocating bad sectors. That is, as shown in FIG. 9, ROI and RO2 are sector numbers 3 and 3 in the spare area, respectively. Track number 8 and sector number 4. It is assigned to the sector with trunk number 8. By doing so, management for each zone becomes easy.

Next, a sixth embodiment will be explained using FIG. 10 and FIG. 1I. In this embodiment, as shown in FIG. 10, a secondary spare area is provided at the outermost periphery of the storage medium. In this embodiment, as in the fifth embodiment, SDM is performed only on RAM egg area 1 to slip bad sectors and assign logical numbers.
OM 8M area 2 is LD with corrected data in spare area 3
He is being replaced by M. The difference from the fifth embodiment is that
As is clear from FIG. 11, the defective sector in the ROM wI area 2 is allocated as is in the spare area.

With this method, the logical numbers in each zone will shift by the amount of slippage, but in this embodiment, a secondary spare area is provided to allocate this shift in logical numbers.

Effects of the Invention As is clear from the above explanation, according to the present invention, RA
Even when the M area and the ROM area coexist in one storage medium 42, defective sectors can be appropriately processed.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of the first embodiment of the present invention, FIG.
FIG. 3 is a diagram showing the configuration of the first embodiment in a planar view to explain defect sector processing, FIG. 4 is a diagram showing the configuration of the second embodiment, and FIG. 5 is a diagram showing the configuration of the second embodiment in a planar view. FIG. 6 is a diagram showing the configuration of the third embodiment; FIG. 7 is a plan view of FIG. 6 to explain the processing of defective sectors; FIG. 8 is a two-dimensional diagram showing the configuration of the fourth embodiment to explain how to process a code area, and FIG. 9 is a two-dimensional diagram showing the configuration of the fifth embodiment to explain how to process a defective sector. FIG. 10 is a diagram showing the configuration of the sixth embodiment, and FIG. 11 is a diagram showing the configuration of the sixth embodiment.
The figure is a planar view of FIG. 10 to explain the process of defective sectors, and FIGS. 12 and 13 are explanatory diagrams of how to process defective sectors in the RAM area in the conventional example. 1...RAM domain area, 2...ROM area, 3...spare area, 4...user area, 5...code area . Name of agent: Patent attorney Akira Okaji and two others I! 1
■ Figure 2 Sector direction □ O-183 in the user area indicates a logical number. Figure 3 Sector direction □ 0-183 in the user area indicates a logical number. FIG. 4 FIG. 5 Sector direction □ × indicates a defective sector. 0-177 in the user area indicates a logical number. Figure 6 W! , 7 Sector direction 1. R2 indicates replacement processing. FIG. 8 Sector direction □ × indicates a defective sector. 0-174 in the user area indicates a logical number. 10 and 12 indicate bad sectors. O-177 in the user area indicates a logical number.

Claims (3)

[Claims] (1) A storage medium comprising a read/write storage area, a read-only storage area, and a spare storage area for storing content to be stored in a memory function defective portion of both storage areas. (2) The storage medium according to claim 1, wherein when the read-only storage area includes a code area, no logical address is assigned to a sector within this code area. (3) A readable and writable storage area, a first spare storage area that stores the contents to be stored in a memory function defective area that has occurred in this readable and writable storage area, a read-only storage area, and this read-only storage area 1. A storage medium comprising: a second spare storage area near the storage area for storing contents to be stored in a memory function defective portion that has occurred in the storage area.