JP2004127368A - Disk drive, disk drive control method and disk drive control program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a disk drive capable of getting out from a lead-in area in a short time, and to provide a disk drive control method and a disk drive control program. <P>SOLUTION: This disk drive is provided with a lead-in area access means for accessing to the lead-in area in the disk, a time information acquisition means for acquiring the final time information of the lead-in area, and an access recovering means (S404) for making the recovery to the desired access position by using the final time information acquired in the time information acquisition means when run into the re ad-in area from the outside of the lead-in area. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a disk drive device, a disk drive control method, and a disk drive control program.
[0002]
[Prior art]
A CD (Compact Disk) has areas such as a lead-in area and a program area. Of these, for example, when accessing the program area, if the user accidentally accesses the lead-in area due to vibration or the like and only obtains a valid relative time within the lead-in area, the original access position is returned. Since it is not possible to obtain information on how many tracks should be moved to return, the user has to move every 100 tracks to escape from the lead-in area and return to the original access position. It should be noted that a document relating to such processing could not be found.
[0003]
[Problems to be solved by the invention]
However, in the above-described method, it takes a long time to move the track at least once until the track escapes from the lead-in area. Then, even if the user escapes from the lead-in area, it takes more time to reseek the original access position from the escape position.
[0004]
An object of the present invention is to provide a disk drive device, a disk drive control method, and a disk drive control program that can escape from a lead-in area in a short time in view of such a problem.
[0005]
[Means for Solving the Problems]
According to the present invention, in the disk drive device (10), a lead-in area access means (S302) for accessing a lead-in area in the disk, and time information for obtaining final time information of the lead-in area. Acquiring means (S304); and an access returning means for returning to a desired access position using the last time information acquired by the time information acquiring means when the vehicle enters the lead-in area from outside the lead-in area. (S404).
[0006]
According to the first aspect, it is possible to provide a disk drive device that can escape from the lead-in area in a short time.
[0007]
In the invention according to claim 2, the time information acquisition unit updates the time information while sequentially reading the lead-in area from a point in time when the lead-in area is accessed to a point outside the lead-in area. (S303).
[0008]
According to the second aspect, from the point of accessing the lead-in area to the point outside the lead-in area, the time information recorded in the lead area is updated while sequentially reading, thereby obtaining the final time information. A disk drive device capable of performing the above can be provided.
[0009]
The invention according to claim 3 is characterized in that the time information obtaining means obtains the last time information when the disk is started.
[0010]
According to a third aspect of the present invention, there is provided a disk drive device capable of recovering even when the disk enters the lead-in area during operation such as disk reproduction, in order to acquire the last time information when starting the disk. Can be.
[0011]
According to a fourth aspect of the present invention, the access return means acquires an absolute position of the entry position on the disk based on the time information at the entry position and the acquired final time information (S403). ) To return to a desired access position.
[0012]
According to the fourth aspect, it is possible to provide a disk drive device capable of acquiring an absolute position from the time information at the entry position based on the acquired final time information.
[0013]
According to a fifth aspect of the present invention, in the disk drive device control method, a lead-in area access step (S302) for accessing a lead-in area in the disk and time information obtaining for obtaining final time information of the lead-in area. A step (S304) and an access returning step (S404) of returning to a desired access position using the time information acquired by the time information acquiring means when the vehicle enters the lead-in area from outside the lead-in area. It is characterized by having.
[0014]
According to the fifth aspect, it is possible to provide a disk drive device control method that can escape from the lead-in area in a short time.
[0015]
The invention according to claim 6 provides a computer with a lead-in area access procedure for accessing a lead-in area in a disc (S302) and a time information acquisition procedure for acquiring last time information of the lead-in area (S304). And an access return procedure (S404) for returning to a desired access position using the time information obtained by the time information obtaining means when the vehicle enters the lead-in area from outside the lead-in area. Disk drive device control program.
[0016]
According to the sixth aspect, it is possible to provide a disk drive device control program that can escape from the lead-in area in a short time.
[0017]
Note that the reference numerals are only examples, and the present invention is not limited to these reference numerals.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0019]
A disk drive according to an embodiment of the present invention will be described with reference to FIG. The disk drive device 10 shown in FIG. 1 includes an MCU (Micro Computer Unit) 11, a focus control circuit 12, a tracking control circuit 13, a head amplifier 14, a data detection unit 15, a motor control circuit 16, It has a head drive motor 17, an optical head 24, a laser control circuit 18, a spindle motor 20, a motor control circuit 19, an FG sensor 22, and an interface 23.
[0020]
The MCU 11 controls the entire disk drive device 10. The focus control circuit 12 is a servo mechanism for keeping the distance between the disk 21 and the optical head 24 constant. The tracking control circuit 13 controls the optical head 24 to follow the pitch of the disk 21. The head amplifier 14 amplifies data read by the optical head 24. The data is detected by the data detection unit 15. The motor control circuit 16 controls the optical head 24 with the optical head drive motor 17. The laser control circuit 18 controls the laser output from the optical head 24. The motor control circuit 19 controls the spindle motor 20 that rotates the disk 21. The FG sensor 22 outputs a signal from a Hall sensor attached to the spindle motor 20. The interface 23 performs an interface between the disk drive device 10 and another device.
[0021]
Next, the MCU 11 will be described with reference to FIG. The MCU 11 includes a CPU (Central Processing Unit) 30, a ROM (Read Only Memory) 31, and a RAM (Random Access Memory) 32, which are connected by a bus. The ROM 91 stores firmware that the CPU 90 executes. The firmware includes an OS (Operating System), a program for controlling registers and peripheral devices, and other programs for controlling a disk drive. The CPU 90 executes the program using the RAM 32 or the like. Note that the ROM 91 may be a nonvolatile storage device, such as a flash memory. In that case, it is possible to add a function or correct a defect later.
[0022]
The configuration of the disk drive device 10 has been described above. Next, the processing of the MCU 11 from the time when the disk 21 is set in the disk drive device 10 until the time when the data recorded on the disk 21 is read will be described with reference to the flowchart of FIG. It will be described using FIG.
[0023]
First, in step S101, the MCU 11 detects that the disk 21 has been set, for example, that the disk tray has been closed. Next, in step S102, the MCU 11 performs a process of determining the presence or absence of a disk and a size determination process. The determination of the presence or absence of a disk is a determination of whether the disk 21 is set on the disk tray. The determination of the size is a determination of the size of the disk 21 such as whether the size of the disk 21 is 8 cm or 12 cm.
[0024]
In the next step S104, the MCU 11 performs a servo adjustment process. This process includes, for example, a process of determining how much power the laser should output by the reflection of the disk 21 on the laser. Next, in step S105, the MCU 11 performs a process on an LIA (Lead In Area) in which information on the disk 21 is recorded. Then, in step S106, the MCU 11 performs a process of detecting the vibration of the disk drive device 10 accompanying the rotation of the disk 21.
[0025]
When the steps S101 to S106 are completed, the MCU 11 starts reading the disk 21 in a step S107. Then, during the reading process, the MCU 11 performs a rotation speed measurement process of the disk 21 in step S108, and controls the disk drive device 10 at an appropriate rotation speed.
[0026]
The description of the flowchart of FIG. 3 has been completed above. Next, the disk presence / absence and size determination processing in step S102, the LIA processing in step S105, the vibration detection processing in step S106, and the rotation speed measurement processing in step S108 will be sequentially described.
[0027]
First, the disc presence / absence and size determination processing in step S102 in FIG. 3 will be described. This process is a process in which the spindle motor 20 is rotated from a state in which the spindle motor 20 is not rotating, and after a certain period of time, the presence / absence and size of the disk are simultaneously determined.
[0028]
The graph shown in FIG. 4 is a graph having the elapsed time after rotating the spindle motor 20 on the horizontal axis and the rotation speed of the spindle motor 20 on the vertical axis. The straight line, the one-dot broken line, and the broken line in the graph show the graphs when there is no disk, when the disk is 8 cm, and when the disk is 12 cm. The rotation speed of the spindle motor 20 can be obtained by measuring the period of an FG output signal output from an FG sensor 22 described later.
[0029]
As shown in the graph of FIG. 4, when there is no disk, the number of rotations immediately rises because the spindle motor 20 is rotated. In the case of an 8 cm disk, the rotation becomes slightly heavier, so that the number of rotations is lower than in the case of no disk. In the case of a 12 cm disk, the rotation speed is further reduced because the disk becomes heavier.
[0030]
As described above, the number of rotations after the elapse of the predetermined time differs depending on the presence or absence and type of the disk. Therefore, for example, the presence or absence and type of the disk can be determined based on the number of rotations measured by “T” on the horizontal axis. By the way, in the case of this graph, the discriminating method is such that when the rotation speed detected at “T” is smaller than A, the disc is judged to be 12 cm, and when the rotation speed is not less than A and smaller than B, the disc is judged to be 8 cm disc. When the rotation speed is greater than B, it is determined that there is no disk.
[0031]
This determination processing will be described with reference to the flowchart of FIG. First, the MCU 11 rotates the spindle motor 20 in step S201. Next, in step S202, the MCU 11 measures the number of rotations of the spindle motor 20 after a lapse of a predetermined time from the rotation. This corresponds to the measurement of the rotation speed at "T" in FIG.
[0032]
In the next step S203, the process branches depending on the measured rotation speed. If the rotation speed is smaller than A, the MCU 11 determines that the disk is a 12 cm disk in step S204, and ends the processing. If the rotation speed is equal to or higher than A, the MCU 11 determines in step S205 whether the rotation speed is smaller than B (> A). If the rotation speed is smaller than B, the MCU 11 determines that the disc is an 8-cm disc in step S206, and ends the process.
[0033]
If the rotation speed is equal to or higher than B, the MCU 11 determines that there is no disk in step S207, and ends the processing.
[0034]
This concludes the description of the disc presence / absence and size determination processing, and then describes the LIA processing in step S105 in FIG.
[0035]
The LIA, which is a lead-in area, is a recording area on the disc that indicates the start of a session. In a music CD or CD-ROM, session data is recorded in the form of a lead-in area, a program area, and a lead-out area from the inner periphery of the disc. In a multi-session, sets of the lead-in area, the program area, and the lead-out area are recorded by the number of sessions.
[0036]
Further, in the lead-in area, TOC (Table Of Contents) in which various kinds of information about the session such as track information in the session are recorded is written.
[0037]
A process for returning to the original access destination when the access destination of the optical head 24 erroneously enters the lead-in area due to, for example, vibration will be described below.
[0038]
FIG. 6 is a flowchart showing details of the LIA processing in step S105 of FIG. In step S301, the MCU 11 moves the optical head 24 to the vicinity of the innermost circumference of the disk 21 and accesses the same. Then, in step S302, the MCU 11 intentionally moves the optical head 24 into the LIA to access the LIA. Next, the MCU 11 reads the LIA while acquiring the relative time information obtained from the LIA. By continuing to read the LIA as it is, the access destination is eventually changed from the LIA to the program area. In step S304, the MCU 11 sets the last relative time in the LIA obtained at that time as the last relative time in the LIA. In the multi-session disc, the MCU 11 performs the process of acquiring the final relative time for the number of LIAs. In the next step S305, the MCU 11 advances the process to step S302 until the process is completed for all the LIAs. When the processing is completed for all the LIAs, the LIA processing ends.
[0039]
Next, processing when the optical head 24 actually enters the LIA will be described with reference to the flowchart of FIG. When the optical head 24 enters the LIA in step S401, the MCU 11 reads the relative time information of the LIA in step S402.
[0040]
Next, the process of step S403, which is a process for obtaining information for returning to the original access destination from the last relative time of the LIA obtained earlier, will be briefly described. Let the final relative time of the LIA be t, and let the relative time of the entry position be v. Further, assuming that the absolute time of the position accessed before entering the vehicle is u, in step S404, the optical head is shifted from the current position by (t−v) + u, so that the access destination is changed to the original access destination by one. It is possible to return by moving once.
[0041]
By doing so, even if the optical head 24 erroneously enters the LIA, it is possible to prevent the useless time caused by temporarily moving the optical head every 100 tracks as in the related art.
[0042]
Conventionally, when the LIA is accessed at around 0: 0.0 as the target access destination, the LIA is escaped by a jump of 100 tracks, and the LIA is accessed again at around 0: 0.0 as the target access destination. However, according to the above-described method, it can be understood that the convergence is quickly achieved when the target of access is around 0: 0.0.
[0043]
Next, the vibration detection processing in step S106 in FIG. 3 will be described. Here, the vibration refers to a vibration generated by the bias of the disk itself. Hereinafter, the vibration detection processing will be described with reference to the drawings.
[0044]
FIG. 8 is a diagram illustrating a pulse of the FG output signal output by the FG sensor 22. As shown in FIG. 8, in this vibration detection processing, first, numbers are assigned from 0 to 7 to the pulses generated each time the disk makes one rotation. Then, a pulse number, which is a timing value, is acquired at a timing at which an error signal, which is a signal when the level exceeds a predetermined level, is detected from among the tracking error signals obtained from the tracking control circuit 13. From the obtained pulse numbers, a moving average of the pulse numbers at which the vibration occurs is obtained as shown in FIG.
[0045]
FIG. 9 is a table showing pulse numbers when vibration occurs and their moving averages. Note that the moving average is obtained for each pulse number obtained three consecutive times. Then, the obtained value is described below the last pulse number among the pulse numbers obtained three times in a row, as shown in “correspondence between pulse number and moving average” in the figure.
[0046]
In the case of FIG. 9, since the moving average value is gathered in the vicinity of 4, it is considered that the bias occurs at the position of the pulse number 4. Thus, when the occurrence of the tracking error is biased toward a specific pulse number, it can be determined that the disk is a vibrating disk.
[0047]
The above-described vibration detection processing will be described with reference to the flowchart of FIG. When recognizing that the vibration has occurred by the tracking error signal exceeding the predetermined level in step S501, the MCU 11 acquires the pulse number at that time in step S502. Then, in step S503, the MCU 11 obtains a moving average as shown in FIG. Since this moving average is not usually an integer, it is determined in advance that, for example, if the moving average value X falls within M ≦ X <M + 1 (M: an integer), it is set to M. The purpose of converting X to an integer is not to identify a position having a bias, but to detect that there is a bias at a certain position.
[0048]
By doing so, it is possible to prevent vibration even if there is a bias due to the disk.
[0049]
In the above description, the pulse numbers from 0 to 7 have been used. However, the number of pulses is not limited to eight, and may be other than 0 to 7.
[0050]
Next, measurement of the number of rotations of the disk will be described. The measurement of the disk rotation speed is performed using the pulse of the FG output signal described with reference to FIG. Specifically, as shown in FIG. 11, the rotation speed is measured by measuring the period of the FG output signal (T seconds in FIG. 11). Therefore, if the period is short, the rotation speed is high, and if the period is long, the rotation speed is low.
[0051]
Therefore, a method of avoiding that the cycle is shortened due to the noise 33 as shown in FIG.
[0052]
Noise 33 as shown in FIG. 12 may be generated and an erroneous determination may be made when noise occurs between a state change in a true pulse and a state change due to the next true pulse. is there. Therefore, erroneous determination can be avoided by regarding a state change that has occurred between a state change in a true pulse and a state change due to the next true pulse as noise.
[0053]
Therefore, it takes at least (T / 2) seconds or more from the occurrence of a state change due to a true pulse to the occurrence of the next state change, as can be seen from the pulse in FIG. This indicates that if there is a state change in a time shorter than (T / 2) seconds, it may be regarded as noise.
[0054]
From this, if the cycle at the highest rotation speed is Tmin seconds and half of Tmin / 2 is t, the state change that occurs within t seconds after the state change occurs is treated as noise. Can be. Next, a flowchart of the processing will be described with reference to FIG.
[0055]
The MCU 11 detects that the state of the FG output signal has changed in step S601. At the same time, the MCU 11 starts measuring time in step S602. Then, in step S603, the MCU 11 detects a state change, and determines whether the state change is noise based on whether t seconds have elapsed in step S604. If t seconds have not elapsed, it is determined to be noise, and the process ends. If t seconds have elapsed, the MCU 11 sets a valid FG output signal in step S605, and ends the processing. Then, in the case of an effective FG output signal, the period is measured and the number of revolutions is measured as in the conventional case.
[0056]
This makes it possible to accurately measure the number of revolutions without being affected by noise.
[0057]
【The invention's effect】
As described above, a disk drive device, a disk drive control method, and a disk drive control program that can escape from the lead-in area in a short time can be obtained.
[Brief description of the drawings]
FIG. 1 is a block diagram of a disk drive device.
FIG. 2 is a block diagram of an MCU.
FIG. 3 is a flowchart showing processing of an MCU when a disc tray is closed.
FIG. 4 is a diagram showing the correspondence between the number of rotations of a spindle motor and elapsed time.
FIG. 5 is a flowchart illustrating a process of determining the presence / absence and size of a disk.
FIG. 6 is a flowchart illustrating LIA processing.
FIG. 7 is a flowchart showing an access destination return process.
FIG. 8 is a diagram showing pulses of an FG output signal.
FIG. 9 is a diagram showing a pulse number and a moving average when vibration occurs.
FIG. 10 is a flowchart illustrating a vibration detection process.
FIG. 11 is a diagram illustrating a cycle of an FG output signal.
FIG. 12 is a diagram illustrating a case where noise occurs in the FG output signal.
FIG. 13 is a diagram illustrating noise determination processing.
[Explanation of symbols]
10: Disk drive device 11: MCU
12 Focus control circuit 13 Tracking control circuit 14 Head amplifier 15 Data detectors 16 and 19 Motor control circuit 17 Optical head drive motor 18 Laser control circuit 20 Spindle motor 21 Disk 22 FG sensor 23 Interface 24 Optical head 30 CPU
31… ROM
32 ... RAM
33 ... Noise

Claims (6)

In a disk drive device,
A lead-in area access means for accessing a lead-in area in the disc;
Time information acquisition means for acquiring the last time information of the lead-in area,
When the vehicle enters the lead-in area from outside the lead-in area, an access return unit that returns to a desired access position using the last time information acquired by the time information acquisition unit is provided. Disk drive device. 2. The time information acquiring unit updates the time information while sequentially reading the lead-in area from when the lead-in area is accessed until the time information reaches the outside of the lead-in area. A disk drive device according to claim 1. The disk drive device according to claim 1, wherein the time information obtaining unit obtains the final time information when starting the disk. The access return unit uses the time information at the entry position and the acquired final time information to acquire the absolute position of the entry position on the disk, thereby returning to the desired access position. 4. The disk drive device according to claim 1, wherein: In the disk drive device control method,
A lead-in area access step for accessing a lead-in area in the disc;
A time information acquisition step of acquiring last time information of the lead-in area,
An access return step of returning to a desired access position using the time information acquired by the time information acquisition means when the vehicle enters the lead-in area from outside the lead-in area. Device control method. On the computer,
A lead-in area access procedure for accessing the lead-in area in the disc,
A time information acquisition procedure for acquiring the last time information of the lead-in area,
A disk drive device control for executing an access return procedure for returning to a desired access position using the time information acquired by the time information acquisition means when the vehicle enters the lead-in area from outside the lead-in area. program.

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