JPH0430332A - Detecting system for stain in optical disk device - Google Patents

Abstract

PURPOSE:To accurately decide the necessity of cleaning by counting the number of all defect sectors present in a prescribed range with the retrieval of an alternate map and outputting a cleaning requirement when a counted number exceeds a prescribed value. CONSTITUTION:An alternate map generating means 101 allocates a selector of a user area 101b of an optical disk when a correction disable error takes place in the area 101b to the alternate area 101c of the optical disk medium, writes sequentially the address of a defect sector and a sector address allocated to the area 101c to an alternate map area 101a to generate an alternate map. A range setting means 102 sets a prescribed range adjacent to the defect sector of the area 101b causing a correction disable error. A counting means 103 retrieves an alternate map to count the number of all defect sectors present within a prescribed range set by the means 102 and a comparator means 104 compares the counted number with a prescribed value to request cleaning when the counted number exceeds the prescribed value. Thus, the cost of the device is reduced without need for a special device to discriminate the stain of a disk medium.

Description

[Detailed Description of the Invention] [Summary] Regarding a dirt detection method for an optical disk device that detects dirt on the optical disk medium or optical head of the optical disk device and issues a cleaning request, a special sensor mechanism is not used to determine dirt. The purpose is to detect dirt on optical disk media and optical heads and accurately determine the need for cleaning.When an uncorrectable error occurs in the user area of the optical disk medium or the user area used, the user Creating a replacement map that allocates sectors of the area to a replacement area of the optical disk medium and sequentially writes the address of the bad sector that has caused an uncorrectable error in the user area and the allocated sector address of the replacement area to the replacement map area of the optical disk medium. means, range setting means for setting a predetermined range adjacent to the bad sector in the user area in which an uncorrectable error has occurred, and changing the number of all bad sectors existing in the predetermined range set by the range setting means. It has a counting means for searching and counting the map, and a comparison means for comparing the count counted by the counting means with a predetermined value and detecting dirt and issuing a cleaning request when the predetermined value is exceeded. do.

[Industrial application field]

The present invention relates to a dirt detection method for an optical disk device, and more particularly to a dirt detection method for an optical disk device that detects dirt on an optical disk medium or an optical head of the optical disk device and issues a cleaning request.

Since optical disk devices use laser light, data errors are likely to occur due to dirt on the optical disk medium or optical head, and it is essential to clean the optical disk medium and optical head to improve data reliability.

[Conventional technology]

In the conventional cleaning method for optical disk devices, the first method is to write data in sector units, then read this data and write an error correction code (ECC: HRROR).
Check using C0RRECT C0DE),
Alternatively, an ECC check is performed on the read data during reading, and a sector in which an uncorrectable error occurs is determined to be a bad sector, and if this bad sector occurs more than a predetermined number of times,
It was determined that the optical disk medium was dirty and requested cleaning.

As a second method, a complicated mechanism such as a sensor function is provided to detect dirt, and the sensor checks the optical disc medium of the optical disc device to detect dirt.

[Invention or problem to be solved]

With the conventional first method, even if there is dirt in the same place,
Each time this dirty part is accessed, the number of bad sectors occurring in that dirty part increases, and there is a problem in that there is a high possibility that a cleaning request will be made even though cleaning is not necessary.

In the second method, a mechanism for determining dirt is built into the device itself, which is not suitable for reducing the size and weight of the device and increases costs.

The present invention has been made in view of the above points, and the present invention detects dirt on an optical disc medium or optical head without using a special sensor mechanism to determine dirt, and accurately determines the need for cleaning. The purpose is to provide a detection method.

[Means to solve the problem]

FIG. 1 is a diagram explaining the principle of the present invention.

In the same figure, when an uncorrectable error occurs in the user area 101b used by the user of the optical disc, the replacement map creating means 101 stores the user area 101b in which the uncorrectable error has occurred.
The sector 1b is allocated to the replacement area 101c of the optical disk medium, and the address of the bad sector that has generated an uncorrectable error in the user area 101b and the allocated sector address of the replacement area 101c are sequentially written to the replacement map area 101a of the optical disk medium, and the replacement is performed. Create a map.

The range setting means 102 sets a predetermined range adjacent to the bad sector of the user area 101b where an uncorrectable error has occurred.

Counting means 103 searches the replacement map and counts the number of all bad sectors existing in a predetermined range set by range setting means 102.

Comparing means 104 compares the count counted by counting means 103 with a predetermined value, and requests cleaning when the predetermined value is exceeded.

[Effect]

In the present invention, when an uncorrectable error occurs in the user area 1 of an optical disk medium, the number of bad sectors within a predetermined range adjacent to this bad sector is counted, and if the counted number is large within the predetermined range, that is, If many bad sectors are distributed in a predetermined range, it is determined that there is dirt on the optical disc medium, and cleaning of the optical disc medium and optical head is requested.

Therefore, as in the first conventional method, an ECC check is performed to count the sectors in which uncorrectable errors have occurred.
Since dirt is not determined based on the count alone, even if dirt is present in a single area and this area is repeatedly accessed, no cleaning request is made, and no cleaning request is issued if it is unnecessary.

Further, unlike the second conventional method, there is no need to incorporate a mechanism for determining dirt into the device itself, and the method can be carried out within the existing device.

〔Example〕

FIG. 2 shows a configuration diagram of an embodiment of the system of the present invention.

In the figure, 30 is an optical disc control device, and a control circuit 3
1. Dirt detection processing mechanism 32, data buffer 33, EC
It is composed of a C circuit 34.

Reference numeral 35 denotes an optical disk device, which is composed of a control circuit 36, an erasure circuit 37, a modulation circuit 38, a demodulation circuit 39, and an optical head 40. 41 is an optical disk medium.

The data buffer 33 of the optical disk control device 30 is connected to the terminal 4.
2, and is connected to the host device via the force control circuit 3.
1 is connected to the control circuit 36 of the optical disc device 35 via a control line 43. Further, the data buffer 33 is connected to the control circuit 36 of the optical disc device 35 via a data bus, and the data buffer 33 is connected to the control circuit 36 of the optical disc device 35 via a data bus.
5 is supplied to the ECC circuit 34, where the EC
A C check will be performed. When an uncorrectable error occurs, the ECC circuit 34 notifies the control circuit 31 via a control line.

When the uncorrectable error occurs, the contamination detection processing 32 of the control circuit 31 is supplied with a replacement map area of the optical disk medium, which will be described later, from the data buffer 33 and performs the contamination detection processing. The optical disc device 35 receives control of erasing, writing, and reading from the optical disc medium 41 from the control circuit 31 of the optical disc control device 30 to the control circuit 36. In the case of erasing, the optical disc device 35 uses the optical head 40 to control the erasing, writing, and reading from the optical disc medium 41. 41, and in the case of writing, the data to be written modulated by the modulation circuit 38 is sent to the optical head 4.
0 to the optical disk medium 41, and in the case of reading, the optical head 40 reads the data stored on the optical disk medium 41, and the demodulation circuit 39 demodulates the data.

The optical disk medium 41 has the structure shown in FIG. 3(A). For example, each track has 16 sectors and the tracks are numbered 1 to N. User area 1, which is used by the user, and the sector in which an uncorrectable error has occurred are allocated. It consists of a spare area 2 and a spare map area 3 that stores a spare map consisting of defective sector addresses and spare addresses. The first sector 4 of the replacement map area 3 is as shown in FIG. 3(B).
The start address of the replacement map and the count number of the replacement map are stored, indicating the size of the replacement map. Further, this sector 4 can be composed of the start address of the replacement map and the last address of the replacement map, as shown in FIG. 3(D).

FIG. 3(C) shows the elements constituting the replacement map in the replacement map area 3 on the optical disc medium 41. FIG. If user area 1 is accessed and an uncorrectable error occurs in the ECC check, the sector address where the uncorrectable error occurred in user area 1 is set as the bad sector address, and the sector where the uncorrectable error occurred is set in replacement area 2. allocation,
For allocation, the sector address of the previous spare area 2 is used as a spare address, and a spare map consisting of a bad sector address and a spare address is created and stored in the spare master/knob area 3 as shown in FIG. 3(C). do.

FIG. 4 shows a flowchart of an embodiment of the stain detection process according to the present invention. This process is performed on the third
The process starts when an uncorrectable error occurs in the user area shown in FIG. First, a bad sector in which an uncorrectable error has occurred is allocated to a spare area 2 (step 61).

After replacement, the defective sector distribution range in the user area 1 of the optical disk medium 41 is set as shown in FIG. 5(A) (step 62).

User area 1 of the optical disk medium 41 where an uncorrectable error has occurred due to the data check of the ECC circuit 34 shown in FIG.
In FIG. 5A, defective sectors are indicated by "D", and defective sectors that have already been replaced are indicated by "x". The bad sector distribution range is set, for example, to a range of ±2 tracks and ±2 sectors adjacent to the bad sector D in which the uncorrectable error has occurred.

In this case, the track width of the bad sector distribution range is 5 tracks and the sector width is 5 sectors.

Thereafter, the replacement map area 3 is searched to count the number of replaced bad sectors that are either at the bad sector address of the replacement map or within the bad sector distribution range (step 63).

Next, the count value is compared with a predetermined value (step 64).

For example, if the predetermined value is lO, if the count value of replaced bad sectors is less than the predetermined value as shown in FIG. 5(B), no cleaning request is made and the process ends. If the number is greater than a predetermined value as shown in FIG. 5(C), a cleaning request is issued (step 65), and the process is terminated.

FIG. 6 shows a configuration diagram of an embodiment of a cleaning system to which the method of the present invention is applied. In this figure, the same parts as in FIG. 2 are designated by the same reference numerals, and their explanations will be omitted. In FIG. 6, the optical disk control device 30 detects dirt on the optical disk medium 41 as described above, and when it is determined that cleaning is necessary, issues a cleaning request to the optical disk device 35. When the optical disk device 35 receives the cleaning request, it lights up the cleaning request display lamp 70. Next, the optical disk medium 41 that has been ejected manually is put into the medium cleaning device 71 to clean the optical disk medium 41. Next, the head cleaning disk 72 is attached to the optical disk device 3.
5 to clean the optical head 40.

When the cleaning of the optical head 40 in the optical disk device 35 is completed, the cleaning request display lamp 70 goes out, the head cleaning disk 72 is ejected, and the cleaning process ends.

In this way, when an uncorrectable error occurs in the user area 1 of the optical disk medium 41, the number of bad sectors adjacent to this bad sector within the bad sector distribution range is counted, and the counted number is calculated within the bad sector distribution range. If there are many,
That is, if many bad sectors are distributed within the bad sector distribution range, it is determined that there is dirt on the optical disk medium 41, and cleaning of the optical disk medium 41 and the optical head 40 is requested.

Therefore, as in the first conventional method, an FCC check is performed to count the sectors in which an uncorrectable error has occurred, and even if there is dirt in a single part, this part is not considered dirty. Since a cleaning request is not issued even if accessed repeatedly, the number of cleaning operations can be reduced. In addition, unlike the second conventional method, there is no need to incorporate a mechanism for detecting dirt into the device itself.
Performed within existing equipment.

〔Effect of the invention〕

As described above, according to the present invention, there is no need for a special device for determining dirt on a disk medium, and it can be easily realized with an existing device, reducing the cost of the device, and a device for detecting dirt on a disk medium. Since it does not have a built-in device, the optical disc device can be lightweight and compact. Furthermore, since the cleaning request is made by counting the distribution of bad sectors, unnecessary searches are not performed and the number of times of cleaning can be kept to a minimum, which is useful for improving the performance of the device.

[Brief explanation of drawings]

Fig. 1 is a diagram explaining the principle of the present invention, Fig. 2 is a block diagram of an embodiment of the method of the present invention, Fig. 3 is a disk format of an embodiment of the method of the present invention, and Fig. 4 is a diagram of the method of the present invention. FIG. 5 is a flowchart of an embodiment of dirt detection processing; FIG. 5 is a diagram showing a bad sector distribution range of an embodiment of the method of the present invention; FIG. 6 is a configuration diagram of an embodiment of a cleaning system to which the method of the present invention is applied. be. In the figure, 0 indicates an optical disk control device, 2 indicates a dirt detection process, 4 indicates an FCC circuit, 5 indicates an optical disk device, 1 indicates an optical disk medium, 0 indicates a bad sector, 1 indicates a replacement method bad sector, and 2 indicates a bad sector distribution range. .

Claims (1)

[Scope of Claims] In a dirt detection method for an optical disk device that detects dirt on a disk medium or an optical head of an optical disk device and determines a cleaning request, a user area (101) used by a user of an optical disk medium is provided.
When an uncorrectable error occurs in b), the sector of the user area (101b) where the uncorrectable error occurred is allocated to the spare area (101c) of the optical disk medium, and the uncorrectable error of the user area (101b) occurs. The address of the defective sector and the sector address assigned to the replacement area (101c) are stored in the replacement map area (101c) of the optical disk medium.
Replacement map creation means (101) that sequentially writes to 01a)
and a range setting means (102) for setting a predetermined range adjacent to the bad sector of the user area (101b) in which an uncorrectable error has occurred, and everything existing in the predetermined range set by the range setting means (102). a counting means (103) for searching the replacement map and counting the number of bad sectors; and comparing the count counted by the counting means (103) with a predetermined value and detecting dirt when the predetermined value is exceeded. and a comparison means (104) for issuing a request for cleaning.