JPH05119923A - Disk controller - Google Patents

Abstract

PURPOSE:To provide the disk controller which can process the read operation of data at high speed without waiting for the lapse of time until stabilizing the revolutions of a motor even when reading is requested from a host while the motor is stopped. CONSTITUTION:In the case of reading data from a disk device 5, a comparator 19 compares held address information with the address of data as a reading object so as to detect whether the data of the reading object are held in a buffer memory 13 or not. When the data are stored in the buffer memory 13, an interface controller 17 outputs the relevant data in the buffer memory 13 through a first buffer circuit 11 to the host 3 without revolving the motor in the disk device 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk control device for controlling a read operation and a write operation for a disk device capable of stopping a motor for rotating a disk plate, and more particularly to reading from a host when the motor is stopped. The present invention relates to a disk control device capable of high-speed processing when requested.

[0002]

2. Description of the Related Art FIG. 2 shows a block diagram of a conventional disk controller. The disk control device 101 controls a read operation and a write operation of a CPU (central processing unit) 3 (hereinafter referred to as a host 3) of a personal computer with respect to a disk device 5, and includes a first buffer circuit 11 and a buffer memory. 13, second buffer circuit 1
5, an interface controller 17, and a disk controller 21.

The operation of the disk control device 101 when a read command is issued from the host 3 to read the data of the disk device 5 will be described.

First, when a read command and a parameter from the host 3 are given to the interface controller 17 via the first buffer circuit 11, the interface controller 17 analyzes it. Next, the interface controller 17 checks the contents of the buffer memory 13 to determine whether or not the data in the disk device 5 needs to be read.

The interface controller 17 issues a read command to the disk controller 21 if there is no data of the cylinder designated by the host 3 in the buffer memory 13. In response to this read command, the disk controller 21 causes the disk device 5 to store the corresponding data in the buffer memory 13 via the second buffer circuit 15. When the corresponding data is stored in the buffer memory 13, the interface controller 17
Causes the data to be output to the host 3 via the first buffer circuit 11.

[0006]

A small hard disk drive used in a notebook type personal computer or the like is a battery drive type. In such a small hard disk device, in order to prolong the battery life, the motor of the disk device is stopped to save power when not in use. Then, the disk control device 10 used in such a hard disk device
In No. 1, when a read command is issued from the host 3 when the motor is stopped, the hard disk device 5 is always written not only when the contents in the hard disk device 5 are not stored in the buffer memory 13 but also when the data is stored. It was accessing and reading. For this reason,
There has been a problem that the processing time of reading becomes long by the time (about 2 seconds) until the rotation of the motor becomes stable and the reading becomes possible.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a reading request from the host when the motor is stopped without delaying the rotation of the motor. It is an object of the present invention to provide a disk controller capable of processing a data read operation at high speed.

[0008]

DISCLOSURE OF THE INVENTION The present invention provides a disk control device for controlling read and write operations to a disk device capable of stopping a motor for rotating a disk plate, the read data from the disk device or the disk. A buffer memory for holding data to be written to the device, and whether or not the data to be read is stored in the buffer memory when a command to read data from the disk device is issued while the motor is stopped. When the detection means for detecting and the data to be read are stored in the buffer memory,
An output means for outputting data from the buffer memory is provided regardless of the operating state of the motor.

With such a configuration, in the disk control device of the present invention, the data to be read is held in the buffer memory by the detection means even when the motor of the disk device is stopped during the data read operation of the disk device. It is detected whether or not the data is held, and if the data is held, the corresponding data in the buffer memory is output without accessing the disk device. Therefore, the data read operation can be performed at high speed without the time until the rotation of the motor stabilizes.

Further, the present invention provides a disk control device for controlling a read operation and a write operation for a disk device capable of stopping a motor for rotating a disk plate.
A buffer memory that stores read data from the disk device or write data to the disk device, and address information in the disk device of the data held in the buffer memory, and
While the motor is stopped, when an instruction to read data from the disk device is issued, the address of the data to be read is compared with the address information, and the data to be read is stored in the buffer memory. It is provided with a detecting means for detecting whether or not the output means outputs the data in the buffer memory regardless of the operating state of the motor when the comparison result of the detecting means coincides.

With such a configuration, in the disk control device of the present invention, at the time of the data reading operation of the disk device, even if the motor of the disk device is in the stopped state, the address held in the detecting means is detected by the detecting means. The information is compared with the address of the data to be read, and it is detected whether or not the data to be read is held in the buffer memory. If the data is held, it is stored in the buffer memory without accessing the disk device. The corresponding data of is output. Therefore, the data read operation can be performed at high speed without the time until the rotation of the motor stabilizes.

Further, in the disk control device according to the present invention, the address information may be a cylinder number in the disk device, and the buffer memory may have a capacity of at least one cylinder.

[0013]

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

FIG. 1 shows the configuration of a disk controller according to an embodiment of the present invention. The same components as those in FIG. 2 are designated by the same reference numerals.

The disk control device 1 of this embodiment comprises a first buffer circuit 11, a buffer memory 13, a second buffer circuit 15, an interface controller 17, a comparator 19 and a disk controller 21. Control the read operation and the write operation for.

The host 3 is a C of a personal computer.
It is a PU (Central Processing Unit), and the disk device 5 is an auxiliary storage device such as a magnetic disk device. Further, the disk device 5 includes a disk plate, an access arm, a head, and a control circuit for writing and reading.

The first buffer circuit 11 is a buffer circuit for commands and data between the host 3 and the disk device 5. The buffer memory 13 is a memory that stores data for several cylinders of the disk device 5. The second buffer circuit 15 is a data buffer circuit between the disk device 5 and the buffer memory 13.

The interface controller 17 receives a command from the host 3, analyzes the command, controls the buffer memory 13, and gives an instruction to the disk controller 21 to read or write data to the disk device 5. Take control.

The disk controller 21 is instructed by the interface controller 17 to transmit the disk device 5 and the buffer memory 13 via the second buffer circuit 15.
Controls the data read or write operation between and.

The comparator 19 includes a buffer memory 13
Which cylinder on the disk device 5 is stored as address information of the data currently stored therein, and is instructed by this cylinder and a read command in response to the analysis result of the interface controller 17. Cylinders are compared, and if they match, the interface controller 17 is notified that the corresponding data in the buffer memory 13 can be transferred to the host 3.

Next, the operation of reading data from the disk device 5 by the disk controller 1 of this embodiment will be described.

First, when a read command is issued from the host 3, this command is given to the interface controller 17 via the first buffer circuit 11. The interface controller 17 analyzes this command and detects the number of the designated cylinder. on the other hand,
The comparator 19 is the interface controller 1
The number of the cylinder analyzed by 7 is compared with the number of the cylinder of the data stored in the buffer memory 13, and the result is notified to the interface controller 17. The interface controller 17 receives this notification and determines whether or not it is necessary to read data from the disk device 5.

As a result of the comparison by the comparator 19, if all the data requested to be read from the host 3 are stored in the buffer memory 13, the interface controller 17 does not activate the motor of the disk device 5 and The corresponding data in the buffer memory 13 is output to the buffer 3 via the first buffer circuit 11. Therefore, in this embodiment, data can be read out at high speed.

If the data of the designated cylinder is not stored in the buffer memory 13, the interface controller 17 issues a read command to the disk controller 21. In response to this read command, the disk controller 21 activates the motor of the disk device 5, and the time until the rotation of the motor stabilizes (about 2
After waiting for more than a second), the data of the target cylinder of the disk device 5 is controlled to be stored in the buffer memory 13 via the second buffer circuit 15. The interface controller 17 causes the data stored in the buffer memory 13 to be output to the host 3 via the first buffer circuit 11 and ends the read command.

When the data of the cylinder requested to be read is stored in the buffer memory 13, the contents of the comparator 19 are updated at the same time. As a result, even when the data on the same cylinder is read next time, the data can be read at high speed. Further, since the motor of the disk device 5 remains stopped, it is possible to save labor.

Next, the write operation to the disk device 5 by the disk controller 1 of this embodiment will be described.

First, when a write command is issued from the host 3, this command is given to the interface controller 17 via the first buffer circuit 11. The interface controller 17 analyzes this command. In the case of a write command, in order to speed up the processing, the data transferred following the command from the host 3 is stored in the buffer memory 13 via the first buffer circuit 11, and the content of the comparator 19 is also updated. ..

At this point, the interface controller 17 notifies the host 3 that the write command has ended. After that, the host 3 proceeds to the next process, and the disk control device 1 side writes the data stored in the buffer memory 13 by the previous write command to the disk device 5.

That is, the interface controller 1
7 issues a write command to the disk controller 21. In response to this write command, the disk controller 21 immediately starts the writing operation when the motor of the disk device 5 is driven, but when the motor is stopped, it starts the motor of the disk device 5. ,
After waiting for a time until the rotation of the motor stabilizes (about 2 seconds or more), the data of the buffer memory 13 is controlled to be stored in the target cylinder of the disk device 5 via the second buffer circuit 15.

Even in a small hard disk device, 1
It is composed of cylinders = 32 kB (1 track = 8 kB), and most of the processing for updating data, etc. can be processed within one cylinder except when the system is started up. Can be processed.

Further, the data stored in the buffer memory 13 by the write command and the comparator 19
The cylinder information inside is retained as it is even after being written to the disk device 5, and when the data of this cylinder is read next, the read operation can be processed at high speed.

[0032]

As described above, according to the disk control device of the present invention, the data to be read is stored in the buffer memory when the data read command of the disk device is issued while the motor is stopped. It is designed to output the corresponding data in the buffer memory without accessing the disk device when the data is held, so that the rotation of the motor is stable. There is no need to wait until the operation, and there is an effect that the data reading operation when the motor is stopped can be processed at high speed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a disk control device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a conventional disk control device.

[Explanation of symbols]

 1 Disk Control Device 3 Host 5 Disk Device 11 First Buffer Circuit 13 Buffer Memory 15 Second Buffer Circuit 17 Interface Controller (Control Means) 19 Comparator (Detection Means) 21 Disk Controller

Claims (3)

[Claims] 1. A disk control device for controlling a read operation and a write operation for a disk device capable of stopping a motor for rotating a disk plate, which holds read data from the disk device or write data to the disk device. A buffer memory, a detection unit that detects whether or not the data to be read is stored in the buffer memory when a command to read the data from the disk device is issued while the motor is stopped; A disk control device comprising: output means for outputting data from the buffer memory regardless of an operating state of the motor when data to be read is stored in the memory. 2. A disk controller for controlling a read operation and a write operation for a disk device capable of stopping a motor for rotating a disk plate, wherein read data from the disk device or write data to the disk device is stored. The buffer memory and the address information of the data held in the buffer memory in the disk device are held, and the data to be read when there is a read command of the data of the disk device while the motor is stopped. When the comparison result of this detection means matches with the detection means for detecting whether or not the data to be read is stored in the buffer memory by comparing the address of the motor with the address information, In the buffer memory regardless of the operating status A disk control device comprising: an output unit that outputs data. 3. The address information is a cylinder number in the disk device, and the buffer memory is
The disk control device according to claim 2, which has a capacity of at least one cylinder or more.