JP2002093025A - Magnetic disk drive and data access method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the time delay in data access. SOLUTION: This magnetic disk drive 11 is provided with a low-speed (AV) mode for reading and writing AV data in addition to a high-speed (normal) mode for reading and writing computer data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a magnetic disk drive and a data access method, and more particularly to an AV (Aud).
(io / Video) data is suitable for storage in a hard disk.

[0002]

2. Description of the Related Art In recent years, AV-compatible HDDs (hard disk drives) have become widespread. In such AV-compatible HDDs, in addition to computer data, AV data can be recorded on a hard disk.

Here, since computer data is used for processing in a computer, it is necessary that the data can be read and written as fast as possible and without errors. For this reason, in the conventional HDD, high-speed reading / writing is realized by rotating the hard disk as fast as possible (normal mode).

[0004] On the other hand, since AV data is viewed and heard by humans as video and audio, if it is transmitted at the same speed as reading and writing of computer data, the transmission speed is too high and the video is meaningless to humans. Or voice.

For this reason, in a conventional AV-compatible HDD, A
The V mode is provided to control the behavior of the HDD, buffering is performed on the host side to adjust the sending speed, and even if there is some error in the read data, dummy data is sent to the host side. Control was performed so that transfer was not interrupted.

[0006] In the conventional HDD, a power saving mode for stopping the motor of the HDD even while the device is operating is provided, thereby reducing the power consumption of a portable device having a built-in HDD.

[0007]

However, even when reading / writing AV data, rotating the hard disk at a higher speed than necessary wastes power consumption and takes time until the AV data can be accessed. There was a problem that the delay increased. In particular, in the power saving mode, it takes about several seconds for the motor to change from the OFF state to the rotation speed in the normal mode, and depending on the use situation of the user,
Since such an operation is frequently performed, the above-mentioned problem becomes more remarkable.

An object of the present invention is to provide a magnetic disk drive and a data access method capable of reducing a time delay at the time of data access.

[0009]

According to the first aspect of the present invention, there is provided a first rotation speed setting means for setting a rotation speed of a magnetic disk for accessing computer data. Second rotation speed setting means for setting the rotation speed of the magnetic disk for accessing the AV data; and a computer when the magnetic disk is rotating at the rotation speed set by the first rotation speed setting device. First access means for accessing data for use, and second access means for accessing AV data when the magnetic disk is rotating at the rotation speed set by the second rotation speed setting means. It is characterized by.

Thus, when accessing the AV data, it is possible to set the rotation speed lower than the rotation speed of the magnetic disk when accessing the computer data.
The access time can be reduced by shortening the time from the start of the motor until the rotation reaches a predetermined number of revolutions, and the power consumption can be reduced.

According to the second aspect of the present invention, there is provided a cache memory for storing data, and an allocating means for allocating all storage areas of the cache memory for writing when the AV data is written to the magnetic disk. It is further characterized by being provided.

Thus, before the motor reaches the predetermined number of revolutions, the AV data can be received ahead of schedule, and the access time can be further reduced.

According to the third aspect of the present invention, when the magnetic disk device is not used for a predetermined time, the magnetic disk is rotated at the rotation speed set by the second rotation speed setting means. (1) When the magnetic disk device is not used for a further predetermined time while the magnetic disk is being rotated at the number of revolutions set by the second number-of-rotation setting means, the power of the magnetic disk is And a second power saving means for stopping rotation.

As a result, power consumption can be reduced while immediately responding to AV data write / read requests.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a magnetic disk drive according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a schematic configuration of a magnetic disk drive according to an embodiment of the present invention. FIG.
In the magnetic disk device 11, the magnetic disk 1
2, spindle motor 13, motor driver 14, magnetic head 15, voice coil motor (VCM) 16, head IC 17, bus 18, CPU 19, RAM 20, hard disk controller (HDC) 22, buffer RA
M23, gate array 24 and read / write IC2
5 is provided and connected to the host system 26 to transmit and receive data to and from the host system 26.

The ROM 21 includes a control program for reading / writing computer data (such as personal computer programs and data) and AV data (such as moving image data and audio data), as well as the rotational speed of the spindle motor 13. , And control data for moving the magnetic head 15 to an optimum position and the like. Here, a plurality of control data for a high-speed (normal) mode and a low-speed (AV) mode are stored as control data, and control is performed such that the position of the magnetic head 15 is optimized according to the rotation speed of the spindle motor 13. Is done.

The host system 26 requests the magnetic disk device 11 to read / write computer data or AV data.

When there is a request to read computer data, the magnetic disk device 11 reads high-speed (normal) mode control data from the ROM 21. The motor driver 14 controls the rotation speed of the spindle motor 13 based on the control data, rotates the magnetic disk 12 at a high speed, and controls the magnetic head 15 by the VCM 16.
Control the position of. When the magnetic disk 12 reaches a predetermined high-speed rotation speed, the computer data read by the magnetic head 15 is amplified by the head IC 17, subjected to serial / parallel conversion by the read / write IC 25, and then transferred to the HDC 22. . The HDC 22 stores the data sent from the read / write IC 25 in a buffer R.
The data is buffered in the AM 23, and the data is transmitted in sector units requested by the host system 26.

When there is a write request for computer data, the control data for the high-speed (normal) mode is read from the ROM 21. The motor driver 14 controls the rotation speed of the spindle motor 13 based on the control data, rotates the magnetic disk 12 at a high speed,
The position of the magnetic head 15 is controlled by the VCM 16.
The HDC 22 transfers the computer data to the magnetic disk 12 via the head IC 17 and the read / write IC 25 while buffering the computer data transmitted from the host system 26 in the buffer RAM 23. Write to.

On the other hand, when there is a read request for AV data, the magnetic disk device 11
V) Read control data for the mode. The motor driver 14 controls the rotation speed of the spindle motor 13 based on the control data, rotates the magnetic disk 12 at low speed, and controls the position of the magnetic head 15 by the VCM 16. When the magnetic disk 12 reaches a predetermined low rotation speed, the AV data read by the magnetic head 15 is amplified by the head IC 17, and the read / write IC 25 performs serial / parallel conversion.
Transfer to DC22. HDC 22 is read / write I
The data sent from C25 is buffered in the buffer RAM 23, and the data is sent out in sector units requested by the host system 26.

Further, when there is a request to write AV data, it is assumed that a request to read data from the magnetic disk 12 is not made for a while, and all cache areas of the buffer RAM 23 are allocated for writing. The AV data sent from the host system 26 is forwarded to the buffer R before the magnetic disk 12 reaches a predetermined rotation speed.
Buffering to AM23.

Further, control data for the low speed (AV) mode is read from the ROM 21. The motor driver 14
Based on this control data, the rotation speed of the spindle motor 13 is controlled, the magnetic disk 12 is rotated at a low speed, and the position of the magnetic head 15 is controlled by the VCM 16. When the magnetic disk 12 reaches a predetermined low-speed rotation speed, the HDC 22 transfers the AV data buffered in the buffer RAM 23 to the magnetic head 15 via the head IC 17 and the read / write IC 25, thereby transferring the AV data. The data is written on the magnetic disk 12.

FIG. 2 is a diagram showing a change in the number of revolutions of the spindle motor according to one embodiment of the present invention. Time T1
In, if there is a request to write AV data from the host system 26 while the spindle motor 13 is stopped (for example, when recording is started with a digital video camera),
The spindle motor 13 is started immediately and the magnetic disk 1
Rotate 2.

The magnetic disk device 11 allocates all the cache areas of the buffer RAM 23 for writing, and buffers the AV data sent from the host system 26 in the buffer RAM 23 ahead of schedule.

At time T2, when the magnetic disk 12 reaches a predetermined rotation number for the AV mode, the AV data buffered in the buffer RAM 23 is transferred to the magnetic head 15, and the AV data is written to the magnetic disk 12. (Period C).

Next, at time T4, when there is a write request for computer data from the host system 26 (for example, when naming a recorded file,
In this case, the kana-kanji conversion process by the IME is necessary), the cache area of the buffer RAM 23 is returned to the normal mode, and the rotation speed of the magnetic disk 12 is shifted from the low-speed rotation to the high-speed rotation.

At time T5, when the magnetic disk 12 reaches a predetermined number of revolutions for the normal mode, the computer data buffered in the buffer RAM 23 is transferred to the magnetic head 15, and the computer data is transferred to the magnetic disk 12. (Period D).

Next, at time T6, the motor forcible OF
When there is a request for F, the rotation of the spindle motor 13 is stopped.

On the other hand, when writing the AV data only in the conventional high-speed (normal) mode, if there is a request for writing the AV data from the host system 26 while the spindle motor 13 is stopped (time T1), the magnetic data is written. Disc 1
2 reaches a predetermined number of rotations for the normal mode (at time T
3) Writing of AV data to the magnetic disk 12 is performed.

Therefore, in the conventional high-speed (normal) mode only, even if there is a request to write AV data at time T1,
Although the AV data cannot be written on the magnetic disk 12 until time T3, in the present embodiment, the provision of the low-speed (AV) mode makes it possible to shorten the write start time on the magnetic disk 12 by the time A. At the same time, power consumption can be reduced. Also, when writing the AV data, by allocating all the cache areas of the buffer RAM 23 for writing, it is possible to receive the data earlier by the time B.

In the above-described embodiment, the method of writing AV data while the spindle motor 13 is stopped has been described. However, when the magnetic disk 12 is requested to write AV data while the magnetic disk 12 is rotating at high speed in the normal mode. Alternatively, writing the AV data may be performed after the rotation speed of the magnetic disk 12 is shifted to low speed rotation. Thus, power consumption can be further reduced.

FIG. 3 is a flowchart showing the operation in the AV mode of the magnetic disk drive according to one embodiment of the present invention. In this embodiment, the HDD AUTO P
A low-speed (AV) mode is provided in addition to the POWER OFF function. In the following description, a hard disk drive (HDD) will be described as an example of the magnetic disk device 11.

In FIG. 3, when the system power is turned on, the HDD is shifted from the normal mode to the AV mode (step S1). When the HDD itself is started, it is operated in the normal mode. This is because it is necessary to read the OS from the HDD when the device is started.

Next, it is determined whether or not the HDD needs to be read / written, for example, whether or not the user has requested the writing of AV data (step S2).
If it is not necessary to read / write, it is determined whether it is the sleep start time (step S3). In the case of the sleep start time, the HDD motor is stopped (step S4), and the process returns to step S2.

On the other hand, if the read / write of the HDD is necessary, it is determined whether the HDD motor is stopped (step S5). If the HDD motor is not stopped, the read / write process of the HDD is performed (step S5). S8).

On the other hand, when the HDD motor is stopped,
The rotation speed of the HDD motor is increased to the low speed mode (step S6). Then, in the case of writing AV data, the cache allocation is all changed to write, so that a request from the host can be accepted as soon as possible (step S7).

Next, read / write processing of the HDD is performed, and the process returns to step S2.

FIG. 4 is a flowchart showing an operation in a power saving mode of the magnetic disk drive according to one embodiment of the present invention. In this embodiment, a low speed (AV) mode is used as a power saving mode.

In FIG. 4, the power saving timer for measuring the passage of time is reset (step S11).

Next, it is determined whether or not the user has used the HDD (step S12).
Is not used (step S13), the mode shifts to the low-speed rotation mode (step S14).

Next, while operating in the low-speed rotation mode, it is determined whether the user has used the HDD (step S1).
5) When the user has used the HDD, the mode is returned to the normal mode (step S18), and the user further operates the HDD for a certain period of time.
Is not used (step S16), the motor power is turned off.
FF is set (step S17).

As described above, by using the low-speed rotation mode as the power saving mode, it is possible to immediately respond to AV data write / read requests while reducing power consumption. In addition, it is possible to access the computer data write / read request in a shorter time than when the magnetic disk is normally rotated from the motor stopped state, thereby reducing the time delay in data access. It becomes possible.

In the above-described embodiment, the method of shifting to the power saving mode when the user does not access the HDD for a certain period of time has been described. You may make it transfer to a power mode.

[0045]

As described above, according to the present invention,
It is possible to reduce a time delay at the time of data access and reduce power consumption.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a schematic configuration of a magnetic disk drive according to an embodiment of the present invention.

FIG. 2 is a diagram showing a change in the rotation speed of a spindle motor according to an embodiment of the present invention.

FIG. 3 is a flowchart showing an operation in an AV mode of the magnetic disk device according to the embodiment of the present invention.

FIG. 4 is a flowchart showing an operation in a power saving mode of the magnetic disk device according to one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Magnetic disk drive 12 Magnetic disk 13 Spindle motor 14 Motor driver 15 Magnetic head 16 Voice coil motor 17 Head IC 18 Bus 19 CPU 20 RAM 21 ROM 22 HDC 23 Buffer RAM 24 Gate array 25 Read / write IC

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) H04N 5/781 F-term (Reference) 5D044 BC01 CC05 DE02 DE12 DE17 DE23 DE29 DE38 GK10 HL02 5D066 AA02 5D109 KB05 KB24

Claims (4)

[Claims] 1. A first rotation number setting means for setting a rotation number of a magnetic disk for accessing computer data, and a second rotation number setting means for setting a rotation number of a magnetic disk for accessing AV data. First access means for accessing computer data when the magnetic disk is rotating at the rotational speed set by the first rotational speed setting means; and wherein the magnetic disk is the second rotational speed setting means. And a second access unit for accessing the AV data while rotating at the number of revolutions set in (1). 2. The system according to claim 1, further comprising: a cache memory for storing data; and an allocating unit for allocating all storage areas of the cache memory for writing when the AV data is written to the magnetic disk. The magnetic disk device according to the above. A first power-saving means for rotating the magnetic disk at a rotation speed set by the second rotation-speed setting means when the magnetic disk device has not been used for a predetermined time; A second power saving unit for stopping the rotation of the magnetic disk when the magnetic disk device is not used for a further predetermined time while the magnetic disk is being rotated at the rotation speed set by the number setting unit; The magnetic disk drive according to claim 1, further comprising: 4. A normal mode for setting a rotation speed of a magnetic disk for accessing computer data, and an AV mode for setting a rotation speed of a magnetic disk for accessing AV data. Data access method.