JPH0684283A - Transfer method for magneto-optical disk data - Google Patents

Abstract

PURPOSE:To prevent the reading speed of magnetic disk data from being reduced too much even when the number of defective sectors is increased. CONSTITUTION:An alternating processing sector table 3 is provided inside a magneto-optical disk device 2, data relating to the defective sectors to which alternating processing is performed are stored in the table 3 and the data to which the alternating processing is performed are read first by referring to the table 3 to be stored in a controller buffer 7. Thus, the moving distance of a head is reduced and a transfer speed is accelerated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data transfer method in a magneto-optical disk device having a function of replacing a defective sector with another normal sector.

[0002]

2. Description of the Related Art Generally, data is read from a magneto-optical disk device by a host computer by instructing the magneto-optical disk device of a head sector number and the number of consecutive sectors to be read. A controller that interfaces between the host computer and the magneto-optical disk device normally stores sector data in the controller buffer in order of sector number from the magneto-optical disk device. In the magneto-optical disk device, a defective sector is replaced with a sector in a replacement area secured in a specific area. The controller employs the following method, for example, in order to store the replacement sector in the controller buffer in the order of the sector number when there is a replacement sector in the continuously read sectors. That is, the magnetic disk device reads continuous sectors up to immediately before the replaced sector, but if there is a defective and replaced sector,
Each time, the optical head is sought to the normal sector which is the replacement destination, and the data of the normal sector is read. After that, the head is returned to the normal sector immediately after the replaced sector, and the same operation is repeated.

FIG. 4 is a flow chart showing the above operation in detail. That is, when the magneto-optical disk device receives a predetermined command including the starting sector number and the number of sectors to be read / written from the host computer in step S1, it checks the start address and the number of sectors in step S2, and in step S3 the controller buffer. A pointer is set to determine an empty area (simply referred to as a buffer). Then, in step S4, it is determined whether or not the final sector is closer than the next replacement sector. If not close (N), the process proceeds to step S5, and if close (Y), the process proceeds to step S8. In step S5, the number of sectors up to the next replacement sector is calculated. In step S6, the normal sector data is read, and in step S7, the replacement sector data is read. In step S8, the number of sectors up to the final sector is calculated, and in step S9, the data of the normal sector is read.

[0004]

However, in the above-described read method, the seek operation of the head occurs with respect to the normal sector of the replacement destination every time there is a defective sector, so that the data read speed becomes slow. There is. In particular, when the continuous sectors to be read include two or more defective sectors, the optical head reciprocates between the normal sector and the replacement sector area by the number of defective sectors. As a result, the larger the number of defective sectors, the slower the data read speed. Therefore, an object of the present invention is to prevent the data reading speed from being lowered so much even if the number of defective sectors increases.

[0005]

In order to solve such a problem, the present invention reads data from a magnetic disk by a magneto-optical disk device having a function of replacing a defective sector with another normal sector. When transferring the data to the controller buffer, the sector data of the area where the data of the sector which is defective and has undergone the replacement process is stored is read out, first stored in the corresponding position of the controller buffer, and then the regular data is stored. It is characterized in that only normal sector data is read from the data area and stored in the corresponding position of the controller buffer.

[0006]

When the data is read from the magneto-optical disk device, the moving distance of the optical head is reduced by reading the data of all defective sectors in the read range first.
Improve data transfer speed.

[0007]

1 is a flowchart showing an embodiment of the present invention, and FIG. 2 is a system configuration diagram to which the present invention is applied. First, FIG. 2 will be described. 1 is a host computer (CPU), 2 is a magneto-optical disk device, 3 is a replacement processing sector table, 4 is a controller control unit, 5 is a host interface unit, 6 is a buffer manager, 7 is a controller buffer, and 8 is a disk drive. Are shown respectively. The host computer (CPU) 1 is connected to the magneto-optical disk device 2 via the host interface unit 5, and gives a command such as a leading sector number to read / write, a sector number, and the like. At the time of writing, write data is sent to the magneto-optical disk device 2 following the command, and at the time of reading, sector data is received from the magneto-optical disk device 2. It should be noted that the exchange of commands and data between the host computer 1 and the magneto-optical disk device 2 is performed by, for example, a handshake method for each byte.

The replacement processing sector table 3 is a part particularly added according to the present invention. That is, conventionally, the disk drive 8 reads data in the order of the information series including the replacement sector and stores the read data in the controller buffer 7 in the same order. On the other hand, according to the present invention, the replacement processing sector table 3 is referred to, the address information of the sector replaced within the read range is obtained thereby, and these data are read first, and these data are stored in the controller buffer 7. Store so that the correct information sequence is stored in. Next, the data in the normal sector is read and stored in the same manner. Finally, the data is transferred to the host computer 1 in the order of the address of the controller buffer 7 so that the order of the information series is established.

This processing operation is shown in FIG. 1, which is characterized in that a step for referring to the replacement processing sector table 3 is added as shown in step S3. That is, when the magneto-optical disk device 2 receives a predetermined command from the host computer 1 (step S1), the magneto-optical disk device 2 checks its start address and the number of sectors by its controller control unit 4 (step S1).
2) Referring to the replacement processing sector table 3, it is determined whether there is a replaced sector within the read range (step S3).

As a result, if there is a sector that has been replaced, when the total number is known (step S4), a seek is made to the replacement sector area, and the data of the normal sector corresponding to the defective sector is transferred to the controller buffer. 7
It is stored in the corresponding position (step S6). At this time, similarly to the case of FIG. 4, the buffer pointer is set (step S5). Finally, the normal data area is sought, and the data of the sectors other than the replaced sectors in the area to be read is stored in the corresponding position of the controller buffer 7 (step S8).
At this time, the buffer pointer is reset to secure the regular data area (step S7). If the replacement sector does not exist as a result of the determination in step S4, the buffer pointer is reset in step S7, and the seek to the replacement sector is not performed and the seek operation is performed directly on the regular data area. Data is stored based on the reset pointer of 7.

Here, with respect to the magnetic disk as shown in FIG. 3A, the command from the host computer 1 specifies to read the data from the sectors 1 to 12 of the magnetic disk in this order. The operation when there are two defective sectors 4 and 7 and these are replaced by 4'and 7 ', respectively, will be described. in this case,
By setting the buffer pointer, the area of the controller buffer 7 in which the read data should be stored is secured from (1) to (12) as shown in FIG. Further, by referring to the replacement processing sector table 3 in step S3, it can be seen that there is a defective sector. Therefore, the data of the replacement sectors 4'and 7'is read out first, and this is read in the corresponding areas 4 and 7 of the controller buffer 7. To store. Then, seeking is performed on the regular data area, and the data of the sectors other than the exchanged sectors 4 and 7 of the sectors 1 to 12 are transferred to the corresponding areas 1 to 3, 5, 6, 8 of the controller buffer 7.
Stored in ~ 12. In FIG. 3B, the first stored data is shown on the left side of the shaded portion, and the regular stored data is shown on the right side.

[0012]

According to the present invention, it is possible to determine whether or not there is a replaced sector within the number of sectors to be read from the head sector designated by the command from the host computer by using the replacement sector table. Check and, if there is a replacement sector, store only that data in the corresponding position in the controller buffer first, and then store only the data in the normal sector from the normal data area in the corresponding position in the controller buffer. Since it is stored in the memory, it is possible to minimize the movement (seek) of the optical head, which takes time to operate, and as a result, it is possible to increase the data transfer rate. The more noticeable it becomes.

[Brief description of drawings]

FIG. 1 is a flow chart showing an embodiment of the present invention.

FIG. 2 is a block diagram showing an apparatus to which the present invention is applied.

FIG. 3 is an explanatory diagram for specifically explaining the operation of the present invention.

FIG. 4 is a flowchart for explaining the operation of the conventional example.

[Explanation of symbols]

1 ... Host computer (CPU), 2 ... Magneto-optical disk device, 3 ... Alternate processing sector table, 4 ... Controller control unit, 5 ... Host interface unit, 6 ... Buffer manager, 7 ... Controller buffer, 8 ... Disk drive.

Claims (1)

[Claims] 1. A magneto-optical disk device having a function of replacing a defective sector with another normal sector reads data from a magnetic disk and transfers the data to its controller buffer. The sector data of the area in which the data of the specified sector is stored is first stored in the corresponding position of the controller buffer, and then only the data of the normal sector is read from the normal data area and the corresponding data of the controller buffer is read. A method for transferring magneto-optical disk data, characterized by storing in a position.