JP3151985B2 - Magneto-optical disk controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magneto-optical disk controller, and more particularly to a magneto-optical disk controller for performing high-speed substitution processing.

[0002]

2. Description of the Related Art A magneto-optical disk is a disk-shaped storage medium having a spiral storage area. The spiral storage area specifies a position by a track and a sector. A sector is the minimum unit for writing and reading data on a magneto-optical disk, and a track is composed of a plurality of sectors.
One round of the magneto-optical disk is used as a unit.

Each sector stores ID information and data information, and the ID information stores a track number and a sector number indicating its own physical address. The data information can store management information of the magneto-optical disk and data information of the user.

The magneto-optical disk controller reads and writes data in a specific sector by selecting the above-described track and sector and controlling the magneto-optical disk device. In selecting a track, control is performed to move or seek an optical head for reading and writing and to position the optical head at a target track. Further, in selecting a sector, ID information of a plurality of sectors on a specific track is sequentially read in accordance with the rotation of the magneto-optical disk, and comparison and detection with ID information of a target sector are performed. As a result, the target sector is specified, and the data information of the specified sector is read or written.

In practice, portable media such as ISO
DIS10090 has standardized a 90 mm magneto-optical disk. Hereinafter, description will be made using this standard format.

The magneto-optical disk has one surface, 10,000 tracks per surface, 25 sectors per track, and 512 bytes per sector.
It is determined to be a byte.

In this example, the total storage capacity is one surface * 1000
0 tracks * 25 sectors * 512 bytes, but in practice, all storage areas of the magneto-optical disk drive
Data cannot be stored. This is because there may be a defect in which data cannot be stored on the magneto-optical disk surface. In this case, the sector containing the defect needs to be replaced with a normal sector. Further, the data of the user cannot be stored in the area of the defect list indicating which defective sector is replaced with which normal sector.

Referring to FIG. 9, the defect list is stored in defect management areas DMA1, DMA2, DMA3 and DMA4 on the disk, and the same contents are stored in all four. The defect management areas (DMA1 to DMA4) include the definition sector DDS of the magneto-optical disk and the initial defect list PDL.
And a sub defect list SDL.

As an alternative processing method, an initial defect list PD
Two methods, a method using L and a method using the sub-defect list SDL, are standardized. Here, a slipping method using the initial defect list PDL will be described as an example. The slipping method is a method of skipping a defective sector, storing data to be stored in the defective sector in the next normal sector, and storing the data sequentially thereafter. Less than,
Unless otherwise specified, the defect list indicates the initial defect list PDL.

Referring to FIG. 10 showing the contents of the defect list, the 0th byte and the 1st byte of this defect list are identification data of the initial defect list PDL. The second and third bytes indicate the number of defects in the defect list. The fourth and subsequent bytes indicate a defective address. One defective address is 3
It consists of 4 bytes of a byte track number and a 1-byte sector number.

For example, assume that the 0th, 2nd, 4th, 5th, and 8th sectors of the 100th track are defective, as in the example of FIG. In this case, the defect list is as shown in FIG. In FIG. 5, [n, m] represents the n-th sector and the m-th sector of the track.
In the following description, it is similarly described.

Next, an alternative process of this type of conventional magneto-optical disk control device will be described.

Referring to FIG. 6, which is a block diagram of a conventional magneto-optical disk controller, a magneto-optical disk system includes a magneto-optical disk device 2 controlled by a magneto-optical disk controller 1 and an auxiliary storage device. And a host system 3 owned by the user. A magneto-optical disk (not shown) is inserted into or ejected from the magneto-optical disk device 2 as a storage medium.

The magneto-optical disk controller 1 includes a conversion unit 10 for inputting a logical block from the host system 3 and converting it to a logical address, and a conversion unit 11 for inputting a logical address and a defect list and converting it to a physical address. A write unit 12 for writing data to a sector of the magneto-optical disk indicated by a physical address, a read unit 13 for reading data from a sector of the magneto-optical disk device 2 indicated by a physical address, a write unit 12 and a read unit 13
And a storage unit 15 for storing the defect list created by the defect list creation unit 14 and the defect list read by the read unit 13 from the magneto-optical disk. Consists of The magneto-optical disk control device requires error correction means and the like in addition to the above.

FIGS. 7 and 8 show a flow relating to an alternative process of the conventional magneto-optical disk control device 1. FIG.

When a magneto-optical disk whose defect list is shown in FIG. 5A is inserted into the magneto-optical disk device 2, the magneto-optical disk control device processes the flow in FIG. 7A.
The defect list is read from the magneto-optical disk by the reading means 13 (step A11), and the defect list is stored in the storage means 15 (step A12). The stored defect list has the same configuration as the defect list of the magneto-optical disk, that is, as shown in FIG.

In a magneto-optical disk used for the first time, a defect list is created simultaneously with formatting.
The defect list is stored on the magneto-optical disk. Referring to FIG. 7B showing this flow, the magneto-optical disk is initialized by the writing means 12 (step B11), and if the ID information cannot be detected due to a defective sector, the defect list creation means 14 A list is created (steps B12 and B13). Then, by the lead means 13,
Verify, that is, whether the data is correctly written on the magneto-optical disk (Step B14), and if there is a defect, a defect list is created by the defect list creating means 14 (Steps B15 and B16). The created defect list is stored in the storage unit 15 (step B17). Finally, the defect list is stored in the magneto-optical disk by the writing means 12 (step B18).

Next, the data reading operation of the magneto-optical disk controller 1 including a defective sector will be described by taking as an example a case where reading from the first sector to the second sector of the 100th track of the logical address is performed. . the first,
The host system 3 reads the magneto-optical disk using logical blocks starting from 0 that can be accessed as a continuous storage area in order to make tracks and sectors accessible without being aware of alternative processing. Here, for simplicity, the number of bytes in one block is 512 bytes. In the example shown in FIG. 9, the next sector of the second defect management area, that is, the logical address [3, 0] is the 0th logical block.

Referring to the flow of FIG. 7C, the logical block number input from the host system 3 is converted into a logical address by the conversion means 10 (step C1).
1, C12). When the block 2426 and the logical block 2427 are input from the host system, the block number, ie, 2426, is divided by the number of sectors per track 25, and the quotient 97 is added to 3 of the start track to 10
Track 0, start sector 0 plus surplus 1 plus 1
No. sector is required. The logical block No. 2427 is similarly converted to the logical address [100, 2].

Next, the logical address is converted into a physical address by the conversion means 11 (step C13). The data is read from the magneto-optical disk by the read means 13 at the obtained physical address (step C14).

Referring to FIG. 8A showing the flow of the means for converting a logical address into a physical address, first, a physical address at which reading is started is determined. The logical address [100, 1] is temporarily assigned to the temporary address (step D11).

Subsequently, one of the defect lists shown in FIG.
The defective address [100,0] and the temporary address [10
0, 1] (step D12). In this case, since the temporary address is larger, one address is added to the temporary address (steps D13 and D14). Subsequently, the defect address [100, 2] of the second defect list and the temporary address [10
0, 2], since the values match, add one address to the temporary address (steps D12, D13, D1).
4). Subsequently, the defect address [1] in the third defect list
[00, 4] and the tentative address [100, 3], the tentative address is smaller, and the logical address / physical address conversion is completed using the tentative address as the physical address (steps D12, D13, D15). In this way, the physical address [100, 3] at which to start reading is obtained.

Next, a physical address at which reading is completed is obtained. Although it can be obtained in the same manner as the physical address at which reading is started, it will be obtained using the end state described above.
The logical address [100,2] to start reading is subtracted from the logical address [100,2] to end reading, and this value is added to the logical address [100,3] to start reading, and the temporary address is temporarily set. [100, 4] is obtained.
When the defect address [100, 4] of the third defect list is compared with the temporary address [100, 4], the values match, and thus the address is added to the temporary address. Subsequently, the defect address [100, 5] of the fourth defect list and the temporary address [1]
00, 5], the values match, so one address is added to the temporary address. Subsequently, the defect address [100, 8] and the temporary address [100, 6] of the fifth defect list
Since the temporary address is smaller than the logical address, the logical address / physical address conversion is completed using the temporary address as the physical address. In this way, the physical address [100, 6] at which the reading is completed is obtained.

As described above, the conventional magneto-optical disk controller performs logical address physical address conversion. However, in the actual read operation, the physical address [100,
3] to the physical address [100, 6], there is a defective sector, so that it is not possible to read continuously, and the read operation of the physical sector [100, 3] and the physical sector [1]
00, 6].

The above-mentioned conventional magneto-optical disk controller 1
Is a method based on successive approximation in which a physical address is obtained by comparing with a defect address in a defect list one by one, so that the time required for logical address physical address conversion is long and the response speed of the magneto-optical disk device 2 is slow. There are drawbacks.

In order to improve this drawback, various devices have hitherto been devised. Here, a method using a binary search as another conventional example will be described with reference to a flow shown in FIG. The flow shown in FIG.
The description is omitted because it is the same.

First, a logical address [100, 1] is searched from the defect list using a binary search (step D21). In this case, since there is no corresponding defective address, the next defective address, that is, the second defective address [100, 2] is indicated, and the binary search ends.
The value obtained by subtracting 1 from the position of the defect list for which the binary search has been completed, that is, one is the physical address [100,
1]. The obtained 1 is added to the logical address, and the temporary address [100, 2]
(Step D22).

The subsequent steps are the same as those in FIG.
When the second defective address is compared with the temporary address, the values match, so the address is added to the temporary address. Then 3
Comparing the defective address [100, 4] of the third defect list with the temporary address [100, 3], the temporary address is smaller, and thus the logical address / physical address conversion is completed using the temporary address as the physical address (step D12). ,
D13, D14, D15). Thus, the physical address [100, 3] at which to start reading is obtained.

Next, a physical address at which reading is completed is obtained. Similarly, when the read range is large, it is faster to use the physical address using the binary search. However, when the read range is small, the number of objects to be compared is small, so that the above-described successive approximation processing is fast.

[0030]

In the processing based on the successive approximation described above, for example, the ISO DIS10090 is compared with a maximum of 2048 defective addresses. Also, in the method using binary search, the larger the number of defect lists, the more advantageous compared to successive comparisons.
Widely known.

However, even when a binary search is used, it is necessary to perform successive comparison after the binary search. In the worst case, it is necessary to compare a maximum of 12 defective addresses in the binary search and a maximum of 2047 defective addresses in the successive approximation. For example, when 2047 sectors are consecutively registered in the defect list from the defect address [100, 0] and the defect address [100, 2], the logical address [100, 1] may be converted to a physical address. .

As described above, the conventional magneto-optical disk controller performs successive comparisons in order to convert a logical address into a physical address in the process of replacing a defective sector, and the response speed of the magneto-optical disk device is low. It has the drawback.

[0033]

The magneto-optical disk controller of the present invention creates a defect list 1 indicated by a logical address from physical address information of a defective sector obtained by performing writing and verifying on a magneto-optical disk. First means and second means for reading the defect list 2 indicated by a physical address recorded on the magneto-optical disk and then creating the defect list 1 indicated by a logical address from the defect list 2 Thus, the defect list 1 is held.

Further, the defect list 1 may be held by having third means for converting the defect list 1 indicated by a logical address into the defect list 2 indicated by a physical address.

Further, the defect list 1 created by the first means and the second means may be searched to convert a logical address to be accessed into a physical address.

[0036]

FIG. 1 is a block diagram showing a magneto-optical disk control apparatus according to a first embodiment of the present invention.
The magneto-optical disk control device 4 according to the present invention converts the defect list from a physical address to a logical address.
The configuration is the same as that of the conventional magneto-optical disk control apparatus except for a conversion unit 21 for converting a defect list from a logical address to a physical address and a conversion unit 22 for inputting a logical address and a defect list and converting them into a physical address. . The same components are denoted by the same reference numerals.

Referring to FIG. 2 and FIG. 3 showing the flow relating to the alternative processing of the magneto-optical disk control device 4 together,
When the magneto-optical disk is inserted into the magneto-optical disk device 2, the magneto-optical disk control device 4 reads a defect list from the magneto-optical disk as in the conventional example (step A1).
1). The read defect list is converted by the conversion means 20 from a physical address to a defect list composed of logical addresses, and the defect list is stored in the storage means 15 (steps A21 and A12).

In a magneto-optical disk used for the first time, formatting is performed, a defect list is created at the same time, and a physical address of the defect list is converted into a logical address.
The defect list is stored on the magneto-optical disk.

FIG. 2 shows the flow. Initializing the magneto-optical disk as in the conventional example, converting the defect list detected at the time of writing and verification into a defect list composed of logical addresses by the conversion means 20, and storing the created defect list. (Steps B21 and B21)
17). Finally, the defect list is converted into a defect list composed of physical addresses by the reverse conversion means 21 and stored on the magneto-optical disk by the writing means 12 (step B).
22, B18).

The conversion means 20 subtracts (n-1) from the n-th defective address to obtain the n-th logical defective address. The inverse conversion means 21 adds (n-1) to the n-th logical defect address to obtain the n-th logical address.

When the defect list stored in the magneto-optical disk is as shown in FIG.
It is converted as shown in FIG. The first defective address [1
[00,0] is (1-1) minus the first logical defect address [100,0]. Similarly, the second defective address [100, 1] is obtained by subtracting (2-1) from the second defective address [100, 1]. Similarly, the third defective address [100, 4] is the logical defective address [100, 2] and the fourth defective address [100, 5].
Is the logical defect address [100, 2] and the fifth defective address [100, 8] is the logical defect address [100, 4]
Respectively.

Next, as in the conventional example, as for the data reading operation of the magneto-optical disk control device 4 including the defective sector, the case where the reading from the first sector to the second sector of the 100th track of the logical address is performed. An example will be described.

The logical block number input from the host system 3 is converted into a logical address by the conversion means 10 as in the conventional example (steps C11 and C12). When the block 2426 and the logical block 2427 are input from the host system, they are converted into a logical address [100, 1] and a logical address [100, 2], respectively.

Next, the conversion means 22 converts the logical address into a physical address (step C23). The data is read from the magneto-optical disk by the read means 13 at the obtained physical address (step C14).

Referring to FIG. 3A showing a flow for converting a logical address to a physical address, first, a logical address [100,
1] (step D31). In this case, the binary search ends when the address matches the second logical defect address [100, 1]. Subsequently, when the logical address is compared with the third logical defect address [100, 2] in the next defect list, the logical address is smaller, and the comparison ends (step D32). The value of the position of the defect list for which the comparison has been completed, that is, two, is the logical address [100,
1]. The logical address at which to start reading is obtained as a physical address [100, 3] by adding the obtained 2 to the logical address.

Next, a physical address at which reading is completed is obtained. Similarly, when the read range is large, it is faster to use the physical address using the binary search, but when the read range is small, the successive approximation processing is fast. In the present embodiment, in order to understand a binary search using a defect list composed of logical addresses, the binary search is used.

When the logical address [100, 2] is searched by using a binary search, the search is terminated when the logical address matches the third logical defective address (steps D31 and D32). Subsequently, the logical address and the next item in the defect list, namely, 4
Comparing with the logical defective address [100, 2],
Since they match, the comparison is continued (steps D33 and D3).
2). If the logical address is smaller than the fifth logical defect address [100, 4], the comparison is terminated (steps D33 and D32). The value of the position of the defect list for which comparison has been completed, that is, four, is the logical address [10
0, 1]. The physical address for ending the read is obtained as a physical address [100, 6] by adding the obtained 4 to the logical address (step D34).

In the first embodiment, when the physical address obtained by the binary search is a defective sector,
Successive comparison is required as in the conventional example. In the case of the successive approximation of the conventional example, the tentative address is incremented by 1 until the tentative address becomes smaller than the defect list, and the comparison is performed. Starting from the list, if a defect list larger than the logical address is found, the process can be terminated, so that the process can be completed more quickly than in the conventional example.

However, in the worst case, the binary
A comparison with a maximum of 12 times in the search and a maximum of 2047 defect addresses in the successive comparison are required. For example, the defect address [100, 0] and the defect address [1] are added to the defect list.
When 2047 sectors are registered continuously from [00, 2], the logical address [100, 1] may be converted to a physical address. In this case, the logical address defect list includes 2047 consecutive defective addresses [100, 0] and [100, 1].

For this reason, when the physical address obtained after the binary search is a defective sector, a process of searching for a discontinuous point of a logical defective address on the defect list is performed, and a search is performed from the line at the searched position. If a value obtained by subtracting 1 is added to a logical address, it can be converted to a physical address.

In this case, depending on how to make a process for searching for a discontinuous point, if it is created by applying a binary search method to a logical address larger than or smaller than the logical address, a maximum of 12 times can be performed. Continuous points can be detected. In other words, the physical address can be obtained by a total of 24 comparisons, that is, a binary search up to 12 times and two times.

Next, a second embodiment of the present invention will be described. The second embodiment solves one of the disadvantages of the first embodiment.

In the first embodiment, when there are a plurality of identical logical defective addresses, the physical address obtained by the binary search based on the logical address may be a defective sector, and the physical address which is not the closest defective sector is determined. You need to find a sector.

In the second embodiment, a method will be described in which the physical address obtained by the binary search does not need to indicate a defective sector. The difference from the first embodiment is the conversion means and the reverse conversion means of the defect list.

In the ISO DIS10090, the number of sectors per track is determined to be 25, so that the sector numbers are 0 to 24. On the other hand, the sector number in the defect list can be represented from 0 to 255. Therefore, at the time when the defect list is converted from a physical address to a logical address, the conversion method is converted from the first embodiment to the next conversion method.

After subtracting (n-1) from the nth defect address and converting it to the nth logical defect address, the sector number is doubled and a defect list is created as a new logical defect address.

When the defect list is stored on the magneto-optical disk, the defect list indicated by the logical address is created by performing the inverse conversion in the same manner as in the first embodiment, and written to the magneto-optical disk. In the reverse conversion, the n-th logical defect address whose sector number has been doubled is multiplied by one half (n-1).
Is added and the method is used as the n-th physical defect address.

In the defect list shown in FIG.
A defect list shown in (c) is created. The first defective address [100, 0] is obtained by subtracting (1-1) and doubling the result to obtain the first logical defective address [100, 0].
Similarly, the second defective address [100, 2] is (2,
-1) is subtracted and then doubled to obtain the second logical defect address [100, 2]. Similarly, the third defective address [100, 4] is a logical defective address [100, 4],
The fourth defective address [100,5] is the logical defective address [100,4] and the fifth defective address [100,5]
8] is converted to a logical defect address [100, 8].

Next, a case where reading is performed will be described.

First, when retrieving the logical address [100, 1], a binary search is performed with a value obtained by doubling the sector number and adding 1, that is, address [100, 3]. In this case, since there is not always a matching defective address, the binary search is terminated with the third address [100, 4] (step D41). The value obtained by subtracting 1 from the value of the position of the defect list for which comparison has been completed, that is, 2
One is the value of the defective sector existing up to the logical address [100, 1]. The physical address at which reading is started is obtained as a physical address [100, 3] by adding the obtained 2 to the logical address (step D42).

Next, a physical address at which reading is completed is obtained. The logical address [100, 2] indicates that the sector number is 2
Multiply and add 1, convert to address [100,5], and search. Because there is no matching defective address,
The binary search ends with the fifth address [100, 8]. The value obtained by subtracting 1 from the value of the position of the defect list for which comparison has been completed, that is, 4 is the logical address [10
0, 2]. The physical address at which to start reading is obtained as a physical address [100, 6] by adding the obtained 4 to the logical address.

As described above, according to the second embodiment, the logical address / physical address conversion can be performed without performing the sequential comparison, which is a drawback of the first embodiment, and the high-speed magneto-optical disk controller can be used. Can be realized.

Further, a defect list is created with a physical address at the time of formatting, and the defect list is stored in the magneto-optical disk. Then, the physical address of the defect list is converted into a logical address, thereby converting the defect list into a physical address at the time of formatting. It is also possible to reduce the time without performing the conversion process.

Also, one item of the defect list is composed of 8 bytes, the physical address is stored in the lower 4 bytes, and the upper 4 bytes are converted into a logical address and stored, thereby obtaining the logical address of the upper 4 bytes. It is also possible to perform logical address / physical address conversion by performing a search using the method and reading the physical address of the lower 4 bytes.

According to the first and second embodiments, in the method of converting a logical address to a physical address when a defect list is created with a logical address, the logical address of the defect list composed of physical addresses is converted to the physical address. As with the method, it can be easily inferred by those skilled in the art that various measures can be taken.

[0066]

As described above, according to the present invention,
In the process of replacing a defective sector, the logical address to the physical address conversion process can be performed at a higher speed by using the logical address defect list as compared with the case where the physical address defect list is conventionally used. And a high-speed magneto-optical disk control device can be realized.

In addition, since a process of converting a defect list of a physical address into a defect list of a logical address is performed as preparation, the time required for inserting and formatting a magneto-optical disk is longer than in the conventional example. Also, when a defect list is stored in a magneto-optical disk, the process of converting the defect list into a physical address is performed, so that the storage time of the defect list becomes longer than in the conventional example.

However, there is a difference that the conversion of the defect list is performed when the magneto-optical disk is inserted and when the disk is formatted, whereas the conversion of the logical address to the physical address is performed by frequent operations such as reading and writing. For this reason, the present invention that speeds up frequent processing can realize a magneto-optical disk control device that operates at high speed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a magneto-optical disk control device according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing control of the magneto-optical disk control device according to the first embodiment of the present invention.

FIG. 3 is another flowchart showing the control of the magneto-optical disk control device according to the first embodiment of the present invention.

FIG. 4 is a table showing a defect status of a 100th track.

FIG. 5 is a table showing the contents of a defect list. FIG. 5 (a) is a defect list composed of physical addresses, and FIG. 5 (b) is a defect list composed of logical addresses converted according to the first embodiment. (C) is a defect list composed of logical addresses converted according to the second embodiment.

FIG. 6 is a block diagram showing a configuration of a conventional magneto-optical disk control device.

FIG. 7 is a flowchart showing control of a conventional magneto-optical disk control device.

FIG. 8 is another flowchart showing the control of the conventional magneto-optical disk control device.

FIG. 9 is a table showing defect management areas.

FIG. 10 is a table showing the contents of an initial defect list.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conventional magneto-optical disk control device 2 Magneto-optical disk device 3 Host system 4 Magneto-optical disk control device according to the present invention 10 Logical block / logical address conversion means 11, 22 Logical / physical address conversion means 12 Writing means 13 Read / verify Means 14 Defect list creation means 15 Defect list storage means 20 Defect list physical / logical conversion means 21 Defect list logical / physical reverse conversion means

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G11B 20/12 G11B 11/10 G11B 20/10 G11B 21/08

Claims (3)

(57) [Claims] In a magneto-optical disk control device for controlling a magneto-optical disk device, a defect list 1 indicated by a logical address is created from physical address information of a defective sector obtained by writing and verifying a magneto-optical disk. First means and second means for reading the defect list 2 indicated by the physical address marked on the magneto-optical disk and then creating the defect list 1 indicated by the logical address from the defect list 2 A magneto-optical disk control device having the defect list 1. 2. The magneto-optical disk control device according to claim 1, further comprising third means for converting the defect list 1 indicated by a logical address into the defect list indicated by a physical address. 3. The method according to claim 1, further comprising: searching the defect list created by the first means and the second means to convert a logical address to be accessed into a physical address. 2. The magneto-optical disk control device according to claim 1.