JPH11134829A - Head controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a head controller which enables minimization of the time required for operation of writing and reading information to and from an information recordable area when a disk unit for recording and reproducing a information to and from a recording medium is actuated. SOLUTION: In a disk unit A, a first head save area 10 and a second head save area 12 are provided on both sides of a disk location area 5 where a disk is located. The frequency of access to the outer peripheral side in a recordable area of the disk and the frequency of access to the inner peripheral side are compared with each other. At the time of power disconnection, a head is saved in the head save area on the side of the higher frequency of access. For example, if the frequency of access to the outer peripheral side is higher, the head is saved in the first head save area 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a head control device for information, and more particularly, to a head control device for magnetically and / or optically recording information on a disk and reproducing the recorded information. It concerns control.

[0002]

2. Description of the Related Art Conventionally, in a recording / reproducing apparatus for recording information magnetically and / or optically, when the recording / reproducing apparatus is not activated, in order to protect a disk,
The head of the recording / reproducing apparatus is held in a specific area in the recording / reproducing apparatus, that is, in a retreat area. In other words, a retract area is provided outside the information recordable area of the disc when the disc is set in the recording / reproducing apparatus, and the head is retracted in this retract area, so that the recording / reproducing apparatus is carried and the head is impacted. In such a case, the information recordable area of the disk is not damaged even when the disk receives vibration or vibration. Also, instead of providing a save area outside the information recordable area of the disc, a save area may be provided inside the information recordable area of the disc, and the head may be saved in the save area.

[0003]

However, as in the prior art described above, a retract area is provided on either the outside or inside of the information recordable area of the disk, and the head is held in the retract area. In some cases, it takes time to write or read information to or from the information recordable area after the disk is started. That is, for example, in the case where the head is always held outside the information recordable area of the disc, after the recording / reproducing apparatus is started, the operation of writing or reading information to or from a predetermined area on the inner peripheral side of the information recordable area of the disc is performed. When performing an operation, it is necessary to move the head to the inner peripheral side of the information recordable area, and a predetermined time is required when performing a write operation or a read operation.

On the other hand, when the head is always held inside the information recordable area of the disc, after the recording / reproducing apparatus is started, the operation of writing or reading information to or from a predetermined area on the outer periphery of the information recordable area of the disc is performed. When performing an operation, it is necessary to move the head to the outer peripheral side of the information recordable area, and a predetermined time is required when performing a write operation or a read operation. Therefore, an object of the present invention is to provide a head control device capable of minimizing the time required for writing and reading information to and from an information recordable area when the recording / reproducing device is started. Things.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and firstly, is for recording and / or reproducing predetermined information on a recording medium. A head control device for controlling a head, comprising: a plurality of head save areas for saving a head for recording and / or reproducing information in a predetermined case; and a selection for selecting any one of the plurality of save areas. And selecting means having the following. In the head control device of the first configuration, a plurality of head retreat areas for retreating the head are provided, and the selection means selects one of the retreat areas. Therefore, if the head is retracted to a position closer to the next access position of the head, the access position of the recording medium can be quickly accessed, and the time required for information writing and reading operations can be reduced. Can be.

Secondly, in the first configuration, the selection means predicts an access position to the recording medium after the head is retracted, and performs selection in accordance with the prediction. Therefore, the access position to be accessed next is predicted and saved, so that the time required for the information write operation and the information read operation can be reduced. Thirdly, in the first or second aspect, the selection means performs selection in accordance with access information regarding the frequency of access positions of the recording medium during recording and / or reproduction. Therefore, the selection is performed according to the access information relating to the frequency of the access position, so that the probability of the evacuation in the evacuation area close to the next access position to be accessed is increased, and the time required for the information write operation and the read operation can be reduced. it can.

Fourthly, in any of the first to third configurations, a first head retreat area provided on the outer peripheral side of the recording medium placement position in the head control device, And a second head retreat area provided on the side. Therefore, selection is made between the first head retreat area on the outer peripheral side and the second head retreat area on the inner peripheral side. Fifth, the fourth
In the configuration of (1), the information recordable area of the recording medium is divided into a first information recordable area on the outer periphery side and a second information recordable area on the inner periphery side, and the selecting means sets the information recordable area on the first information recordable area. According to the access information having the access frequency of the first information recordable area and the access frequency to the second information recordable area, the access frequency to the first information recordable area is compared with the access frequency to the second information recordable area. And selecting one of the first head retreat area and the second head retreat area. Therefore, the selection is performed according to the access information having the frequency of access to the first information recordable area and the frequency of access to the second information recordable area. Therefore, the time required for the information writing operation and the information reading operation can be reduced. Sixth, in the fourth configuration, the information recordable area of the recording medium is divided into a first information recordable area on an outer peripheral side and a second information recordable area on an inner peripheral side, Detects access information as to whether the position of the head at the time of selecting the head retreat area is in the first information recordable area or the second information recordable area, and according to the detection result, the first head retreat area And the second head retreat area is selected. Therefore, the selection is performed according to the access information as to whether the position of the head at the time of selecting the head retreat area is either the first information recordable area or the second information recordable area, and is close to the next access position to be accessed. The probability of evacuation in the evacuation area is higher,
The time required for the operation of writing or reading information can be reduced.

In a seventh aspect, in any of the third to sixth configurations, the head control device reads the access information stored in the recording medium, and reads the access information based on the access information obtained thereafter. The updated access information is updated, and selection is performed according to the updated access information. Therefore, the access information is read from the recording medium, the access information is updated with the access information obtained by the steady operation such as the recording operation and the reproduction operation, and the selection is performed based on the updated access information. The head can be retracted to the head retraction area closer to the access position. Eighthly, in any one of the third to seventh configurations, access information is recorded on a recording medium when a head retraction area is selected. Therefore, the access information can be cumulatively written by writing the updated access information each time.

Ninth, in any one of the first to eighth configurations, when power supply to a head control device in which the head control device is mounted is stopped,
A head retreat area is selected. Also,
Tenthly, in any one of the fourth to ninth configurations, the recording medium includes a first initial information recording area provided on an outer peripheral side and a second initial information recording area provided on an inner peripheral side. When power is supplied to the head control device while the recording medium is set in the head control device, when the head is retracted to the first head retraction region, It is characterized in that the initial information is read from the first initial information recording area, while the initial information is read from the second initial information recording area when the head is retracted to the second head retraction area. Therefore, since the initial information recording area near the side where the head is retracted is accessed, the time for reading the initial information can be shortened.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. When the structure of a disk device A as a head control device according to the present invention is shown in a plan view, as shown in FIG. 1, a disk placement position 5 where a disk is set, a first head retreat area 10, and a second head retreat area An area 12 is provided, a voice coil motor 34a and an actuator 14 are provided, and a head 24 is provided at a tip of the actuator 14. This disk device A is a recording / reproducing device for recording / reproducing information.

Here, the first head retreat area 10 is
An area for retreating a head provided in a first retreat area outside the information recordable area of the disc as the recording medium when the disc is set, and the second head retreat area 12 This is an area for retracting the head provided in the second retreat area inside the information recordable area of the disc when the disc is set.
The first evacuation area is provided so as to be in contact with the outside of the recordable area of the disk 50 when viewed in plan, while the second evacuation area is provided so as to be in contact with the inside of the recordable area of the disk 50 when viewed in plan. Have been. The information recordable area is an area where information such as video and audio information can be recorded. The voice coil motor 34a is a motor for driving the head 24,
The actuator 14 is for positioning the head 24 on a predetermined track.

FIG. 2 shows a functional configuration of the disk device A. As shown in FIG.
A magnetic head drive circuit 22, a head 24, a reproduction signal processing unit 28, a memory 30, an external instruction unit 32, a servo unit 34, a spindle motor 36, an access information extraction unit 38, and a CPU 40. I have. The head 24 includes a magnetic head 25 and an optical head 26.

Here, the recording signal processing unit 20 processes a signal to be recorded on the disk 50, and performs addition of an error correction code, digital modulation, and the like to the recording signal. Further, the magnetic head drive circuit 22 drives the magnetic head 25 according to a signal input from the recording signal processing unit 20. The magnetic head 25 is used for recording data, and magnetizes the recording film of the disk 50. The disk 50 here is a magneto-optical disk. Also,
The optical head 26 has a semiconductor laser, and has a pickup for receiving laser light emitted from the semiconductor laser to the disk 50. The reproduction signal processing unit 28 reproduces a signal from the optical head 26, and specifically performs clock reproduction, digital demodulation, error correction, and the like. The memory 30 stores initial information and the like. This initial information includes access information described later.

The external instruction section 32 transmits an external instruction to the CPU 40. For example, the external instruction section 32 transmits the instruction content from the operation section to the CPU 40. The servo unit 34 has a voice coil motor 34a, and controls the voice coil motor 34a and the head 24. The spindle motor 36 is connected to the disk 50
Is rotated at a predetermined number of revolutions. The access information extracting section 38 extracts access information of the head 24. Specifically, the access information extracting section 38 fetches information of an address accessed by the head 24 at the time of recording or reproduction and sets this address as a predetermined reference value. The first in the disc in comparison
It is determined whether the access is to the recordable area or to the second recordable area, and the number of each access is counted and held as access information.

The CPU 40 controls the operation of each unit of the disk device A. In particular, FIG.
Each unit is controlled so as to perform the operation shown in the flowchart shown in FIG. The program for performing the operations shown in the flowcharts of FIGS.
0, or one of the CPUs 40 or a plurality of components in them.

In this embodiment, initial information recording areas for recording initial information are provided on the outer peripheral side and the inner peripheral side of the disk 50, and the same initial information is recorded in each initial information recording area. . Here, the initial information recording area on the outer peripheral side of the disk 50 is defined as a first initial information recording area, and the initial information recording area on the inner peripheral side is defined as a second initial information recording area. Here, the initial information indicates a logical structure of information necessary for accessing arbitrary information recorded on the disc 50. For example, the initial information is necessary for recording and reproducing video and audio information. Control information.

The operation of the disk device A having the above configuration will be described. First, the operation when the power is turned off will be described with reference to the flowchart shown in FIG. If there is a power-off operation, an interrupt processing request is issued to the CPU 40 (S10). The disk device A holds information on the address accessed during reproduction and recording of the disk 50 as access information. Specifically, at the time of reproduction and recording, the address (logical address) accessed by the head 24 is managed by the CPU 40. Therefore, the address held by the CPU 40 is sampled at predetermined intervals, and the access information extracting unit 38
Send to The access information extraction unit 38 compares the address with a predetermined reference value to determine whether the address is on the inner side or the outer side. Here, the inner peripheral side divides the recordable area of the disc 50 into two parts, and points to a first recordable area outside the same, and the outer peripheral side refers to an inner second recordable area. Then, the access information extraction unit 38 determines the number of accesses to the outer periphery (hereinafter referred to as “the number of accesses to the outer periphery”)
And the number of accesses to the inner circumference (hereinafter referred to as the “number of accesses to the inner circumference”
Is counted), and CPU information is used as access information.
Output to 40. That is, the access information includes information on the number of accesses on the outer circumference side and information on the number of accesses on the inner circumference side. The CPU 40 stores the access information in the memory 30. If a plurality of recording operations and reproduction operations are performed before the power-off operation, the access information is accumulated. That is, the outer-peripheral side access number and the inner-peripheral side access number are added.

If there is a power-off operation, search for access information is performed (S11). That is, when the voltage disconnection operation is performed, a signal indicating that the operation is performed is sent from the external instruction unit 32 to the CPU 40. Then, the CPU 40
According to the access information stored in the memory 30,
It is determined whether the number of accesses on the outer peripheral side is larger (S1).
2). If the number of accesses on the outer periphery is larger,
The head 24 is retracted to the first head retraction area 10 (S1
3) On the other hand, when the outer access number is equal to or less than the inner access number, the head 24 is retracted to the second head retreat area 12 (S14). That is, the CPU 40 controls the servo unit 34 to retreat to one of the head retreat areas. According to the flowchart of FIG. 3, when the number of accesses on the outer circumference side and the number of accesses on the inner circumference side are the same, the data is retreated to the second head retraction area 12. You may make it retreat to the head retraction area 10. In this embodiment, the time when the power-off operation is performed is the time when the head retreat area is selected. First as above
When the retreat to one of the head retreat area 10 and the second head retreat area 12 is completed, the power is turned off.

When the voltage disconnection operation is performed as described above, a process of writing the access information to the disk 50 is performed. That is, the access information is recorded in the initial information recording area of the disk 50. That is, the access information is recorded in both the first initial information recording area and the second initial information recording area. Specifically, the CPU 40 reads the access information from the memory 30, and the CPU 40
The access information is recorded on the disk 50 via the recording signal processing unit 20, the magnetic head drive circuit 22, and the like.

As described above, in the disk device of this embodiment, the first head save area 10 and the second head save area 12 are provided, and the save area is selected according to the access information of the disk set immediately before. Writing and reading time can be reduced. That is, since the save area is selected in accordance with the access frequency on the inner circumference side and the outer circumference side of the disk used immediately before, if the power is turned off while the disk is inserted and then the power is turned on, the access frequency is high. It can be said that there is a high possibility of accessing the side, and since it is saved in a save area near the side with a high access frequency, the time for writing and reading can be shortened.

According to the flowchart of FIG. 3, when the power is turned off after the disk is removed from the disk device A, the head retraction area is selected in accordance with the access information held in the memory 30. You may do so. Also, when removing the disk,
The access information held at 0 is recorded in the initial information recordable area of the disc.

Next, the operation when the disk device A is started, that is, when the power of the disk device A is turned on will be described with reference to FIG.
This will be described using. In this case, it is assumed that the disk is set in the disk device A when the power is turned on. Also, in the loaded disc,
It is assumed that the same initial information is recorded in both the first initial information recording area and the second initial information recording information.

When the power is turned on, the retreat area of the head 24 is determined (S20, S21). When the head 24 has been retracted to the first head retraction area 10, the first information is read by accessing the first initial information recording area of the disk 50, while the head 24 is moved to the second head retraction area. 12 has been saved, the second initial information recording area of the disc 50 is accessed,
Initial information is read.

That is, when the power is turned on, the fact is transmitted from the external instruction unit 32 to the CPU 40, and the CPU 40 controls the servo unit 34 to read out the initial information. The read initial information is transmitted to the reproduction signal processing unit 2
At 8, the reproduction process is performed and stored in the memory 30. At the time of reading the initial information, the disk 5
The access information in 0 will also be read.

As described above, in the reading of the initial information, since the initial information recording area near the side where the head 24 is retracted is accessed, the reading time of the initial information can be shortened. Thereafter, a steady operation is performed with reference to the initial information. That is, information is written to or read from a predetermined area of the recordable area of the disk 50.

The access information read at the time of startup is updated by the access information obtained in the normal operation. For example, the access information read at the time of startup is updated by access information obtained in a reproducing operation or a recording operation performed after startup, and the outer-side count number and the inner-side count number are added. When the power is turned off while the disk 50 is set, a head retraction area is selected based on the updated access information. For example, in the access information read from the disk 50, the outer side count number is n and the inner side count number is m, and the outer side access number detected in the current steady operation is a. Assuming that the number of inner accesses is b, the access information is updated to m + a for the outer accesses and n + b for the inner accesses.

As described above, since the access information for a certain disk is updated and the selection is made in accordance with the updated access information, the probability of the disk being saved to a save area near the next access position to be accessed increases. In addition, the time required for information writing and reading operations can be further reduced.

In the above description, the case where the disk 50 is started while the disk 50 is set is described. However, when the disk is set or the disk is replaced after the start, the initial information of the newly set disk is set. Is read when the disc is set, and is overwritten in the memory 30. Therefore, as the operation at the time of turning off the power when the disk is replaced, the head save area is selected based on the access information read from the newly set disk. However, when the access information is updated by the steady operation, the head retreat area is naturally selected based on the updated access information.

In the above description, the head save area is selected based on the access information having the outer access number and the inner access number. However, when the head save area is selected, that is, when the power is turned off. When the operation is performed, it is determined whether the head 24 is in the first recordable area or the second recordable area of the disk 50. If the head 24 is in the first recordable area, the first head retreat area 10 is determined. May be retracted to the second head retraction area 12 when the recording area is in the second recordable area.
In this case, position information indicating whether the head 24 was in the first recordable area or the second recordable area of the disk 50 is written to the disk 50 at the time of selection as access information. When the disk device A is activated, the disk is set while power is supplied, or when the disk device A is activated while the disk is set, the access information is read. Then, the access information is updated when the head save area is selected. For example, if the contents of the read access information are p times in the first recordable area and q times in the second recordable area, and the current head position is the first recordable area, the first The recordable area is recorded on the disc 50 as p + 1 times and the second recordable area is set as q times.

In the above description, the access information has been described as being composed of the number of accesses to the outer periphery and the number of accesses to the inner periphery. However, the present invention is not limited to this. Can be identified as long as it can be identified.
For example, a value obtained by subtracting the inner access number from the outer access number may be used as the access information.

In the above description, the head retreat area is composed of the first head retreat area 10 and the second head retreat area 12.
However, the present invention is not limited to this, and a plurality may be used. Further, in the above description, the disk device for the magneto-optical disk has been described. However, the disk device is not limited to this, and the disk 50 may be a disk other than the magneto-optical disk.
Any device having a function of retracting the head from the information recordable area of the recording medium is optional.

[0032]

According to the head control device of the present invention, the time required for writing and reading information to and from the information recordable area when the disk device is started can be reduced. In particular, according to the head control device of the tenth aspect, since the initial information recording area near the side where the head is retracted is accessed, the time for reading the initial information can be shortened.

[Brief description of the drawings]

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

FIG. 2 is a block diagram showing a configuration of a disk device according to an embodiment of the present invention.

FIG. 3 is a flowchart for explaining the operation of the disk device.

FIG. 4 is a flowchart for explaining the operation of the disk device.

[Explanation of symbols]

 Reference Signs List A Disk device 5 Disk arrangement position 10 First head retreat area 12 Second head retreat area 14 Actuator 20 Recording signal processing unit 22 Magnetic head drive circuit 24 Head 25 Magnetic head 26 Optical head 28 Reproduction signal processing unit 30 Memory 32 External instruction unit 34 Servo unit 34a Voice coil motor 38 Access information extraction unit

Claims (10)

[Claims] 1. A head control device for controlling a head for recording and / or reproducing predetermined information on a recording medium, wherein the head for recording and / or reproducing information in a predetermined case is retracted. A head control device comprising: a plurality of head retraction areas; and a selection unit having a selection unit for selecting one of the plurality of retraction areas. 2. The head control device according to claim 1, wherein the selection unit predicts an access position to the recording medium after the head is retracted, and performs selection according to the prediction. 3. The head control device according to claim 1, wherein the selection unit performs the selection in accordance with the access information on the frequency of the access position of the recording medium during recording and / or reproduction. 4. A disk drive according to claim 1, wherein a first head retracting area is provided on an outer peripheral side of an arrangement position of a recording medium in the disk device, and a second head retracting area is provided on an inner peripheral side. The head control device according to claim 1, 2 or 3, wherein 5. The information recordable area of the recording medium is divided into a first information recordable area on an outer peripheral side and a second information recordable area on an inner peripheral side. According to the access information having the access frequency to the first information recordable area and the access frequency to the second information recordable area, the access frequency to the first information recordable area is compared with the access frequency to the second information recordable area. 5. The head control device according to claim 4, wherein one of the first head retreat area and the second head retreat area is selected. 6. The information recordable area of the recording medium is divided into a first information recordable area on an outer peripheral side and a second information recordable area on an inner peripheral side, and the selecting means selects a head retreat area when the head retreat area is selected. The position of the head is between the first information recordable area and the second information recordable area.
5. The information processing apparatus according to claim 4, wherein access information as to whether the information is in any of the information recordable areas is detected, and one of the first head evacuation area and the second head evacuation area is selected according to the detection result. Head control device. 7. The method according to claim 1, wherein the head control device reads the access information stored in the recording medium, updates the read access information with the obtained access information, and makes a selection according to the updated access information. The head control device according to claim 3, 4, 5, or 6. 8. The head control device according to claim 3, wherein access information is recorded on a recording medium when a head retraction area is selected. 9. A head retraction area is selected when power supply to a head control device on which the head control device is mounted is stopped. Or the head control device according to 6 or 7 or 8. 10. The recording medium has a first initial information recording area provided on an outer peripheral side and a second initial information recording area provided on an inner peripheral side. When power is supplied to the head control device in the state where the head is set to
An initial information is read from the first initial information recording area, and when the head is retreated to the second head retraction area, the initial information is read from the second initial information recording area. Item 10. The head control device according to item 4 or 5 or 6 or 7 or 8 or 9.