JPH06242890A - Disk device - Google Patents

Abstract

PURPOSE:To remarkably shorten the time taken to make an access as compared with the conventional one regarding disk devices such as magneto-optical disk devices connected to a host computer and recording and reproducing the required data. CONSTITUTION:Instead of a driver 21 side, a host computer 2 side converts the logic block address and forms a cache memory. The data are read in the unit which can be consecutively reproduced while being decided by the physical limitation of a disk shaped recording medium 6.

Description

Detailed Description of the Invention

[0001]

[Table of Contents] The present invention will be described in the following order. Field of Industrial Application Conventional Technology (FIGS. 2 to 4) Problem to be Solved by the Invention (FIGS. 2 to 4) Means for Solving the Problem (FIG. 1) Action (FIG. 1) Example (1) Configuration of Embodiment (FIG. 1) (2) Effect of Embodiment (3) Other Embodiment Effect of Invention

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk device, and can be applied to, for example, a magneto-optical disk device which is connected to a host computer to record / reproduce desired data.

[0003]

2. Description of the Related Art Conventionally, in this type of disk device, desired data can be recorded / reproduced by connecting to a computer, and in order to simplify this connection, for example, an ISO standard is used between the computer and the host computer. SC
It is designed to be connectable via an SI (small computer system interface) interface. As a result, the user can easily install the driver, which is a disk device, in the host computer, and can easily connect the driver even when the driver is externally attached.

That is, in this type of computer system, an interface cable or the like is connected to physically connect the driver and the host computer, and then an installation program consisting of a predetermined application program is executed to connect the driver and the host computer. Connect logically. Here, in the installation program, data is stored in a predetermined area of the driver so that the host computer can recognize the connection of the driver, whereby the host computer recognizes that the disk device is connected at the time of start-up. It is designed to get you.

By executing the installation program and storing the data in a predetermined area of the driver in this way, various parameters guaranteed within the range of the SCSI interface standard can be changed in the host computer. Thus, for example, the number of write retries can be set, and the manufacturer name, model name, etc. of the drive can be detected as necessary.

In this installation program,
When storing predetermined data in such a driver, a SCSI driver program is also stored in the driver.
That is, as shown in FIG. 2, in this type of computer system 1, the installation program is supplied to the host computer 2 via a floppy disk or the like, and the CPU 3 of the host computer 2 executes the installation program. The data supplied by the floppy disk or the like is output to the driver 4.
As a result, the host computer 2 can be logically connected to the driver 4.

At this time, the host computer 2 executes a predetermined processing procedure according to the host system program stored in the read-only memory (ROM) 5 to load the SCSI driver program from the floppy disk and output it to the driver 4. To do.

In the driver 4, this SCSI driver program is recorded, for example, in a predetermined area of the magneto-optical disk 6, so that in the computer system 1, the processing of the installation program is completed. As a result, the host computer 2 accesses the driver 4 at startup and recognizes that the driver 4 is connected, and then issues a command to the CPU 7 of the driver 4 in accordance with the host system program. In response to this command, the SCSI driver program is read from the magneto-optical disk 6 and output.

In the host computer 2, the read SCSI driver program is stored in the random access memory (RAM) 8 so that the SCSI driver program can be executed as necessary, and the SCSI driver program can be executed.
The driver 4 can be driven according to the interface standard. In addition, in the computer system 1 of this type, a driver program of this type is
Some of them are pre-stored in M5.

Thus, as shown in FIGS. 3 and 4, the host computer 2 executes the SCSI driver program stored in the RAM 8 when a command is issued and data is read by the operating system which is a system program of the host computer. Then, a predetermined interface circuit 11 issues a command to the driver 4, and in response to this command, the driver 4 reads the data requested by the host computer 2 from the magneto-optical disk 6 and outputs it.

At this time, in the host computer 2, the logical block address of the data is output via the SCSI interface to specify the data to be read from the magneto-optical disk 6 and issue the command. To access the magneto-optical disk 6 by converting this logical block address into the track number and sector number of the magneto-optical disk. Further, in the driver 4, the magneto-optical disk 6 is
At the time of accessing, the corresponding data recording position is searched by referring to the defect table 9, and the sector for data reading is switched to the spare sector as required.

That is, in this type of magneto-optical disk 6, whether or not data can be correctly recorded / reproduced is checked in advance in sector units. For sectors in which data cannot be correctly recorded / reproduced, this sector is recorded. A sector is set as a fecto sector, and a spare sector is assigned in place of this sector to record / reproduce data. For this reason, in the driver 4, the correspondence relationship between the sector sectors and the spare sectors is tabulated to form the date table 9. In this sector, the characteristics different for each magneto-optical disk 6 are provided. is there.

However, if the defect table 9 is formed on the driver 4 side and the spare sector is accessed in this way, in this type of driver 4, the host computer 2 side does not judge the data sector without judging the data sector. Thus, the host computer 2 can surely record and reproduce desired data even if the drivers 4 of different manufacturers are connected. Thus, in the driver 4, when the spare sector is accessed in response to the read command to reproduce the data, the reproduced data is sent to the host computer 2.

When reproducing this data, the driver 4 applies the so-called data cache method to reproduce the data in advance and store the reproduced data in the cache memory 10. This makes it possible to shorten the access time of subsequent data. That is, in reproducing the data in this way, the driver 4 simultaneously reproduces a series of data following the data to be reproduced and stores the following series of data in the cache memory 10.

When a read command is issued for all or part of the subsequent series of data, the driver 4 accesses the cache memory 10 instead of the magneto-optical disk 6 and outputs the data. This makes it possible to shorten the data access time.

[0016]

Even if the cache memory 10 is used in this way, however, there is a problem that it takes time to access this kind of driver.

That is, this type of computer system 1
In general, the CPU on the host computer side has a higher processing capability, and when a data read command is issued to the driver 4 in the end, it takes time for the driver 4 to access the data. The host computer 2 side waits and the system as a whole cannot process data efficiently.

The present invention has been made in consideration of the above points, and an object of the present invention is to propose a disk device capable of significantly shortening the time required for access as compared with the conventional case.

[0019]

In order to solve such a problem, in the present invention, in response to a command output from the host computer 2, data is stored in a predetermined disk-shaped recording medium 6 in accordance with a predetermined interface program. In the disk device 21 that records and reproduces the data and inputs / outputs the data to / from the host computer 2, the disk device 21 is logically connected to the host computer 2 according to a predetermined installation program, and the host computer 2 according to the installation program. A cache memory area is formed in a part of the memory area, and the data specified by the host computer 2 is reproduced from the disk-shaped recording medium 6 in response to the read command of the host computer 2, and the reproduced data is stored in the host computer 2. Output it to the data specified by the host computer 2. Ku and stores the reproduced data in Kiyatsushiyumemori region of host computer 2, to select a subsequent data, the data can be continuously play determined by the physical limitations of the disk-shaped recording medium 6.

Further, in the second aspect of the present invention, the physical limitation of the disk-shaped recording medium 6 is the number of sectors per track, the position of the defect, the switching of the recording area, the position of the track jump, or the switching of the head used for reproduction. It is a fixed limit.

Further, in the third aspect of the invention, in response to a command output from the host computer 2, data is recorded / reproduced on / from a predetermined disk-shaped recording medium 6 in accordance with a predetermined interface program, and the data is recorded by the host. In the disk device 21 that inputs / outputs data to / from the computer 2, logical connection is made with the host computer 2 according to a predetermined installation program, and the host computer 2 converts at least the logical block address to at least the disk-shaped recording medium 6 Issue a read command by specifying the track number and sector number of the disk device 21.
Reproduces and outputs data from a predetermined area of the disk-shaped recording medium 6 designated by the track number and the sector number.

[0022]

When a cache memory area is formed in a part of the memory area of the host computer 2 according to the installation program, data specified by the host computer 2 is reproduced from the disk-shaped recording medium 6 and output to the host computer 2. , The data following the data designated by the host computer 2 is reproduced and stored in the cache memory area of the host computer 2, and the following data can be continuously reproduced determined by the physical limitation of the disk-shaped recording medium 6. By selecting the data that can be used, it is possible to access subsequent data in a shorter access time.

The host computer 2 converts the logical block address and specifies at least the track number and sector number of the disk-shaped recording medium 6 to issue a read command, and the disk device 21 issues a disk-shaped position specified by the track number and sector number. By reproducing and outputting the data from the predetermined area of the recording medium 6, the load on the disk device 21 side can be reduced accordingly.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

(1) Configuration of the embodiment In FIG. 1 in which parts corresponding to those in FIG. 3 are assigned the same reference numerals, 20 indicates a computer system as a whole, and in this embodiment, the installation program is installed from the magneto-optical disk 6 to the installation program. Supply. That is, in the host computer 2, when the driver 21 including a magneto-optical disk device is connected and an installation command is input, the ROM
The driver 21 is accessed according to the host system program stored in, and thereby predetermined data is output to the driver 4.

With this, in the computer system 20, the driver 21 can be recognized at the time of subsequent activation. When the driver 21 is recognized in the host computer 2 at the time of start-up, the driver program is subsequently loaded according to the start-up program recorded in a predetermined area of the magneto-optical disk 6. As a result, the driver 21 stores the driver program in the RAM 8 of the host computer 2 according to the startup program.

As a result, in the host computer 2, when a command to access the driver 21 is issued via the operation system, this driver program is executed to access the driver 21.

Further, in the driver 21, when this driver program is stored in the RAM 8, subsequently, a cache memory area is formed in a predetermined area of the RAM 8 according to the starting program, and then an address conversion table of the magneto-optical disk 6 is formed. It is formed in the RAM 8. Here, in the address conversion table, the logical block address for designating the data to be recorded / reproduced in the SCSI interface is set to the cylinder number, the track number of the magneto-optical disk 6,
It is a table for converting the sector number into the head number of the corresponding head.

As a result, in this embodiment, in the computer system 20, when the driver 21 is accessed, the conversion process of the logical block address, which is conventionally executed on the driver side, is executed on the host computer 2 side. . In this way, the host computer 2
If the logical block address conversion processing is executed on the side, the load on the driver 21 side can be reduced accordingly.

On the other hand, generally, in this type of computer system, the host computer 2 side has C
Since the PU has a high capability, the CPU on the host computer 2 side waits for the process on the drive 21 side when recording / reproducing data to / from the driver 21. Especially SCSI
In the interface, the driver 21 can be used as much as the interface system becomes highly versatile.
There is also a feature that the burden on the side is large.

Therefore, if the load on the driver 21 side is reduced and the load on the host computer 2 side is increased correspondingly as in this embodiment, the time required for processing can be shortened as a whole, and the data can be reduced. The time required for access can also be shortened. Further, by supplying this address conversion table from the drive device 21 side, the driver can be easily connected to the desired host computer 2 and, as a result, versatility can be ensured as in the case of the SCSI interface.

Further, in the driver 21, the address conversion table of the magneto-optical disk 6 is formed in the RAM 8, and then the defect table of the magneto-optical disk 6 is formed in the RAM 8. This allows the host computer 2
In the above, after converting the logical block address in the address conversion table, it is determined whether or not to access the defective sector based on the converted cylinder number, track number and sector number address. When accessing, issue an access command for the defect sector.

As a result, in the computer system 20, the host computer side executes the process of retrieving the command table and the reissue of the command table, which is conventionally executed by the driver side.
It is designed to reduce the burden on the first side. As a result, in the computer system 20, the data access time can be shortened and the versatility can be ensured and the overall processing time can be shortened, as in the case where the logical block address is converted on the host computer 2 side. it can.

In particular, when this type of search processing is executed, the time required for the search can be shortened step by step by executing it by the CPU of the host computer 2 side having high capability, and the overall processing time can be shortened accordingly. can do.

That is, after the conversion table and the like are formed in this way, a predetermined processing program is executed in the host computer 2, and when the operation system issues a data read / write command, the SCSI driver Run the program. As a result, when the read / write command of the driver 21 is formed by the format of the SCSI interface, the host computer 2 then converts the logical block address added to this read / write command by the address conversion table, and the magneto-optical disk. The command is converted by converting it to an address such as the cylinder No. 6 or a track number.

When this command is a data read command, the host computer 2 can continuously access in addition to the data actually required based on the address conversion table and the effect table. A command is issued to reproduce the magneto-optical disk 6 in data units.

That is, in this type of magneto-optical disk 6, if the head, cylinder, track and sector are switched, the data cannot be continuously reproduced, and it takes time to read the data. In other words, when the data is read in advance by applying the caching method, if the data is read in advance in such a range that the data can be continuously reproduced due to the physical limitation of the magneto-optical disk 6, the entire data can be read. As a result, the time required for access can be shortened.

In accordance with this principle, the host computer 2 reads data in units of a range in which data can be continuously reproduced by the physical limitation of the magneto-optical disk 6 with reference to the address conversion table and the date table. As described above, the logical block address is converted into an address such as a cylinder or a track number. That is, when the data required by the operation system is the data recorded in a part of the sector, the host computer 2 reproduces the data in units of this sector, whereas the data that is spread over a plurality of sectors is used. If required, the data is read in units of this sector.

On the other hand, when the sector in the middle is a defect sector, one read command is used as the read command up to this defect sector, the read command of the spare sector corresponding to the defect sector, and the defect sector. The command is issued after being decomposed into read commands from the following sectors. Further, when the command is issued in this way, the host computer 2 stores the data input from the driver 21 in the cache memory,
The necessary data is stored in a buffer memory or the like according to the operation system.

When a read command is further issued subsequently, it is judged whether or not the corresponding data is stored in the cache memory, and if a positive result is obtained here, the data is loaded from the cache memory. On the other hand, when the corresponding data does not exist in the cache memory, the host computer 2 again issues a command to the driver 21. Thus, by forming a cache memory in the host computer 2 instead of the cache memory 10 of the driver 21, the time required for access can be shortened as in the case of converting the logical block address.

Particularly in the case of this embodiment, since it is not necessary to transfer the data stored in the cache memory to the driver 21 again, the access time can be shortened accordingly, and the data can be formed in the driver 21. The capacity of the cache memory can be increased as compared with the case where it is used, and the usability can be improved accordingly. Furthermore, when transferring data to be stored in the cache memory in advance from the driver 4, by converting the logical block address and issuing the command, the time required for access can be shortened accordingly.

(2) Effects of the Embodiments According to the above configuration, the host computer side, instead of the driver side, converts the logical block address of the SCSI interface, forms a cache memory, and creates a physical disk of the magneto-optical disk. By reading the data in the unit that can continuously reproduce the data, which is determined by the physical limitation, the conventional S
The access time can be shortened in each stage as compared with the case of accessing data via the CSI interface.

(3) Other Embodiments In the above embodiments, the case where the installation program is supplied via the magneto-optical disk has been described, but the present invention is not limited to this, and the installation program is supplied separately via the floppy disk. It can be widely applied to cases.

Further, in the above-mentioned embodiment, the case where the present invention is applied to the driver composed of the magneto-optical disk device has been described. However, the present invention is not limited to this, and various disk devices such as a hard disk device can be used as a host computer. It can be widely applied when connected and used.

[0045]

As described above, according to the present invention, the logical block address is converted on the host computer side instead of the driver side, the cache memory is formed, and the continuous operation is determined by the physical limitation of the disk-shaped recording medium. Then, by reading the data in a unit that can be reproduced, it is possible to obtain a disk device in which the access time can be shortened as compared with the conventional case.

[Brief description of drawings]

FIG. 1 is a schematic diagram for explaining a computer system according to an embodiment of the present invention.

FIG. 2 is a schematic diagram for explaining a conventional computer system.

FIG. 3 is a schematic diagram for explaining the operation.

FIG. 4 is a schematic diagram for explaining the flow of data.

[Explanation of symbols]

1, 20 ... Computer system, 2 ... Host computer, 4, 21 ... Driver, 6 ... Magneto-optical disk, 8 ... RAM.

Claims (3)

[Claims] 1. In response to a command output from a host computer, data is recorded / reproduced on / from a predetermined disk-shaped recording medium according to a predetermined interface program,
A disk device that inputs and outputs the data to and from the host computer, is logically connected to the host computer according to a predetermined installation program, and is part of the memory area of the host computer according to the installation program. A cache memory area is formed on the host computer, the data specified by the host computer is reproduced from the disk-shaped recording medium in response to the read command of the host computer, and the reproduced data is output to the host computer. Data that can be played back after the data specified by the computer and stored in the cache memory area of the host computer, and the data that can be continuously played back determined by the physical limitation of the disk-shaped recording medium. It is characterized by selecting Disk device to do. 2. The physical limitation of the disk-shaped recording medium is a limitation determined by the number of sectors per track, the position of a defect, the switching of a recording area, the position of a track jump, or the switching of a head used for reproduction. The disk device according to claim 1, wherein: 3. In response to a command output from the host computer, data is recorded / reproduced on / from a predetermined disk-shaped recording medium according to a predetermined interface program,
A disk device that inputs and outputs the data to and from the host computer is logically connected to the host computer according to a predetermined installation program, and the host computer converts at least the logical block address to convert the data to at least the disk. Issue a read command by specifying the track number and the sector number of the disk-shaped recording medium, and the disk device reproduces and outputs the data from a predetermined area of the disk-shaped recording medium specified by the track number and the sector number. The disk device according to claim 1 or 2, wherein: