JPH03214465A - Data reproducing method for disk device - Google Patents

Abstract

PURPOSE:To enable the reproducing of normal data even under the using circumstance of a large vibration and to prevent a data error by forming one track amt. out of data of one tack reproduced N times at a disk rotating speed of N times as fast as a prescribed speed. CONSTITUTION:The data of one track from a disk via a terminal 10 is repeated ly reproduced N times at the speed of N times as fast as the prescribed speed. This reproduced data is demodulated by a demodulation circuit 7 and then stored in a buffer circuit 8. When a servo deviation is detected by a disturbance detector 14, the storing of the data in the buffer circuit 8 is stopped. When it is detected by the circuit 14 that a servo control is accurately operated, the data is stored in the circuit 8. As a result, the data reproduced under the normal operation of the servo control is stored, and the data of one track amt. is thus formed.

Description

[Detailed Description of the Invention] A. INDUSTRIAL APPLICATION FIELD The present invention relates to a data reproducing method for a disk device, and particularly to a data reproducing method for a disk device that is resistant to vibrations and the like. B. Summary of the Invention The present invention reproduces the data of one track recorded on a disk N times using a disk rotation speed corresponding to N times a predetermined data transfer rate, and reproduces data from the reproduced data reproduced N times. By forming one toranoku worth of data and transmitting the formed data at a predetermined data transfer rate, it is possible to perform data reproduction that is resistant to vibrations and the like.

In addition, 1 tora nok of data recorded on the disk is reproduced N times using a disk rotation speed corresponding to N times the predetermined data transfer rate. By forming data for minutes and sending the formed data at a predetermined data transfer rate,
It is resistant to vibrations and allows data playback with fewer data errors. For example, one trunk's worth of data recorded on a disk is reproduced using a disk rotation speed that is N times the predetermined data transfer rate. The data for one trunk is stored in the buffer memory, and the data is sent out at a predetermined data transfer rate. Further, for example, data of one track recorded on a disk is reproduced N times using a disk rotation speed corresponding to N times a predetermined data transfer rate, and the reproduced data is stored in a buffer memory for N trunks, Data processing is performed on the stored data for N tracks to form data for one track, and the formed data is sent out at a predetermined data transfer rate. C. Conventional technology disc devices, e.g. C for playing compact discs
In a D player, the disk is moved at a constant linear velocity (CLV) by a spindle motor.
A laser beam is irradiated along a spiral track formed on the disk, and the music program (digital data) recorded as a pinot train on the disk is irradiated with a laser beam. Regeneration is performed by detecting changes in intensity.

Furthermore, the error rate when reproducing data in a CD player can be, for example, about 10-S, and error detection codes and error correction codes are used to correct some errors, and in normal usage environments. This has been done so that there are no problems.

By the way, in the case of car-mounted CD players and portable CD players, unlike stationary type CD players used at home, very large vibrations are applied, for example, the optical head that scans the track may come off the trunk, etc. The control may not operate properly (the servo may come off), and normal data playback may not be possible. In this case, even if the error detection code and error correction code described above were used, the error could not be corrected, and playback of the music program was hindered. D. Problems to be Solved by the Invention The present invention has been made in view of the above-mentioned circumstances, and it is an object of the present invention to obtain normal playback data with a disk device, especially in an environment where vibrations are relatively large, such as in a vehicle or a portable device. The purpose is to make it possible to reduce the occurrence of data errors.

E. Means for Solving the Problems In order to solve the above problems, in a data reproducing method for a disk device according to the present invention, one
The data of the track is reproduced N times using a disk rotation speed corresponding to N times the predetermined data transfer rate, the data for one track is formed from the reproduced data of the N times, and the data of the formed data is is sent at the specified data transfer rate above. In addition, the data of one track recorded on the disk is reproduced N times using a disk rotation speed corresponding to N times the predetermined data transfer rate. , and transmits the formed data at the predetermined data transfer rate.Also, the data of one track recorded on the disk is transmitted using a disk rotation speed corresponding to N times the predetermined data transfer rate. The error-free data out of the reproduced data reproduced N times is stored in one track of vanofer memory to form one trunk's worth of data, and the formed data is sent out at the predetermined data transfer rate. Also, the data reproduced N times by reproducing the data of the l trunk recorded on the disk using a disk rotation speed corresponding to N times the predetermined data transfer rate is stored in the bathophore memory for N tracks; Data processing is performed on the stored data for N tracks to form data for one trunk, and the formed data is sent out at the predetermined data transfer rate.

F. Function: The data reproduction method for a disk device according to the present invention reproduces the data of one track recorded on a disk N times using a disk rotation speed corresponding to N times the predetermined data transfer rate, and reproduces data for one trunk. data at a predetermined data transfer rate. Also, the l recorded on the disc
The data on the track is reproduced N times using a disk rotation speed corresponding to N times the predetermined data transfer rate, and after data processing is performed, the data for one track is sent out at the predetermined data transfer rate. Also, the data of one track recorded on the disk is played back N times using a disk rotation speed corresponding to N times the predetermined data transfer speed, and the data without errors is stored in the buffer memory for one track. , sends l tracks worth of data at a predetermined data transfer rate. In addition, the data of one track recorded on the disk is played back N times using a disk rotation speed corresponding to N times the predetermined data transfer speed, stored in a buffer memory for N tracks, and subjected to data processing. After that, data for one track is sent out at a predetermined data transfer rate. G. Embodiment Hereinafter, an embodiment of a data reproducing method for a disk device according to the present invention will be described with reference to the drawings. FIG. 1 is a block circuit diagram of a disk device to which the present invention is applied. In FIG. 1, a disk l is rotated by a spindle motor 2 at a constant linear velocity, for example, which corresponds to N times the prescribed data transfer rate. The disk 1 is, for example, a CD.
This is a disc for use in music programs, and on disc L, music programs are recorded with frame synchronization signals, sub-coding consisting of control bits, address bits, etc., and cyclic codes (CRC).
:Cyclic Redundancy Code) and other redundant focuses are recorded along the track as pit rows.

The optical head 3 includes, for example, optical components such as a laser diode, a collimator lens, an objective lens, a beam splitter, and a cylindrical lens, and a photodetector divided into predetermined positions, and directs a laser beam onto the recording surface of the disk l. irradiation, and detect the intensity change of the reflected light by the pits together with the RF amplifier 4 having a matrix configuration, and also detect a focus error signal by, for example, a so-called astigmatism method, and detect a tracking error signal by, for example, a so-called bush-pull method. It looks like this. The RF amplifier 4 binarizes the reproduced signal from the optical head 3 and supplies it to a phase locked loop (hereinafter referred to as PLL) 5, and also outputs the focus error signal.
A tracking error signal is supplied to a focus servo control circuit 11A and a tracking servo control circuit 11B of the servo control circuit 11, respectively. The focus servo control circuit 11A drives the objective lens of the optical head 3 in the optical axis direction so that the focus error signal from the RF amplifier 4 becomes zero. Further, the tracking servo control circuit 11B is configured to control the RF
The objective lens of the optical henode 3 is driven in the disk radial direction so that the tracking error signal from the amplifier 4 becomes zero. The PLL 5 reproduces the cross signal recorded on the disk from the binarized signal from the R'F amplifier 4. The synchronization detection circuit 6 detects a frame synchronization signal from the reproduced signal using the clock signal of the PLL 5 and pulls in frame synchronization, and also detects when the frame synchronization signal cannot be detected due to the influence of drop-out or ginota, and the frame synchronization is lost. Perform synchronization protection to prevent.

On the other hand, the spindle motor servo control circuit 12
Using the cross signal from LL5 and the frame synchronization signal from the same month detection circuit 6, the spindle motor 2 is rotationally controlled so that the P L L5 clocks.

The demodulation circuit 7 converts the binarized signal mentioned above into, for example, E F
M (Eight to fourteen) demodulation is performed and converted to I sonbol 8-bit data.

The bumper circuit 8 is composed of a memory that stores, for example, one trasock's worth of reproduced data, and temporarily stores the reproduced data from the demodulation circuit Is7, as will be described later.

The error correction circuit 9 is, for example, a so-called CIRC (Cross
s Interleave Reed Solomon
Code) A decoding circuit that corrects errors in the playback data stored in the buffer circuit 8, plays back the original music program data, and outputs it to the terminal IO via the buffer circuit 8 at a specified data transfer rate. do. CPU
For example, when the optical head 3 performs a track jump, the servo control circuit l3 calculates the current track position and the number of tracks to the jump destination from the sub-coding address data demodulated by the demodulation circuit 7.
A control signal is supplied to the thread node servo control circuit IIIC of No. 1.

The above thread servo control circuit + IC is connected to the CPU 1
3, the servo is turned off and the optical head 3 is moved in the disk radial direction. The disturbance detection circuit 14 detects when each servo control from the servo control circuit l1 does not operate normally due to, for example, vibration.
The above-mentioned bath sofa circuit 8 is controlled as described below.

Next, we will explain the operation. One trunk's worth of data from disk I is repeatedly played back N times at a speed N times the speed at which data is sent via terminal IO, and after this played data is demodulated in demodulation circuit 7, it is sent to bumper circuit 8. is memorized. By the way, when the data cannot be reproduced correctly during the data reproduction due to external vibrations, that is, when servo disconnection is detected in the disturbance detection circuit 14, storing the data in the buffer 7 circuit 8 is stopped. do. and,
When the disturbance detection circuit l4 again detects that the servo control has operated correctly, the reproduced data is stored in the bathophone circuit 8. As a result, the data that was reproduced when the servo control was lost is discarded, and the data that was reproduced when the servo control was operating normally is stored in the buffer circuit 18, forming data for one track. It will be done. In this way, in this embodiment, one track of data recorded on a disk is repeatedly played back N times using a predetermined disk rotation speed N times, and one track is read from the N times of data that has been played back. By forming the data of
This enables data reproduction that is resistant to disturbances such as vibrations.

In addition, as mentioned above, by performing data processing such as discarding the data reproduced when the servo control is not operating correctly, data reproduction that is resistant to disturbances such as vibration becomes possible. By storing data reproduced when the servo control is operating correctly in the buffer circuit 8 that stores data for one track to form data for one track, it is possible to prevent disturbances such as vibrations. Enables strong data playback. Incidentally, in the above embodiment, the buffer circuit 8 is constituted by a memory that stores data for summer and winter tracks, but it may also be configured by a memory that stores reproduction data for N tracks. That is, as shown in FIG. 2, for example, the disk 1 is rotated at a rotational speed equivalent to four times the data transfer speed, data on one track is repeatedly reproduced four times, and the data reproduced each time is directly buffered. Store in circuit 8. Then, for example, by taking a majority vote of the data that has been reproduced four times, data for the ■ track is formed. Specifically, as shown in Figure 2, the second word is 16 when played the first time.
If it is played back as ``26J'' in hexadecimal notation, and then played back as ``50'' in hexadecimal notation on the second and subsequent playbacks,
Make "50" in hexadecimal representation the correct playback data. Furthermore, when the reproduced data differs each time the data is reproduced, such as the fourth word, this data is not used.

In this way, data obtained by reproducing N times is stored as is in the bathophone circuit 8, and data for one track is formed by, for example, taking a majority vote of the stored data, thereby reducing the occurrence of data errors. This enables data reproduction that is resistant to disturbances such as vibrations. Note that the above-mentioned majority vote may be performed after error correction. Further, when the above N is not an integer, that is, when the data playback speed from the disk is not an integral multiple of the data transfer speed, the buffer circuit 8 is configured to store data for the minimum integer number larger than N, and the final The data stored during playback will be limited to the middle of one trunk's worth of memory. It should be noted that the present invention is not limited to the above embodiments, and can of course be applied to, for example, a so-called CD-ROM, a write-once optical disk device, a rewritable magneto-optical disk device, a magnetic disk device, etc. . Further, the present invention can be applied to a disk device that uses a disk that rotates at a constant angular velocity (CAV). Further, the buffer circuit 8 may be provided before the demodulation circuit 7.

H. Effects of the Invention As is clear from the above explanation, according to the method of the present invention, one track of data recorded on a disk can be repeatedly reproduced N times using a predetermined disk rotation speed N times. By forming one trunk's worth of data from the data reproduced N times, it is possible to perform normal data reproduction even in a usage environment where vibrations are relatively large, such as in a vehicle.

Furthermore, in the method of the present invention, the occurrence of data errors can be reduced by performing data processing on the reproduced data that has been reproduced N times to form data for one track.

For example, in a bathofa that stores data for one trasok,
Data reproduced when the servo control is operating correctly can be stored to form error-free data for one track.

For example, by storing the data obtained by reproducing N times as is in the vanofa, it becomes possible to form data for one track by taking a majority vote of the stored data, thereby preventing the occurrence of data errors. It can be less.

In other words, even in operating environments with relatively large vibrations, It is possible to reproduce data with high reliability.

[Brief explanation of drawings]

FIG. 1 is a block circuit diagram of a disk device to which the present invention is applied, and FIG. 2 is a diagram showing data stored in a buffer circuit. Disk spindle motor buffer circuit servo control circuit Spindle motor servo control circuit Disturbance detection circuit

Claims (4)

[Claims] (1) One track of data recorded on the disk is played back N times using a disk rotation speed that is N times the predetermined data transfer speed, and one track is recorded from the N times of playback data. 1. A data reproducing method for a disk device, comprising: forming data, and transmitting the formed data at the predetermined data transfer rate. (2) Data of one track recorded on the disk is reproduced N times using a disk rotation speed corresponding to N times the predetermined data transfer rate. Data processing is performed on the reproduced data for one track. 2. The data reproducing method for a disk device according to claim 1, further comprising the step of: forming a data reproducing method. (3) Data of one track recorded on the disk is reproduced using a disk rotation speed corresponding to N times the predetermined data transfer rate. Among the reproduced data N times, error-free data is collected for one track. 3. The data reproducing method for a disk device according to claim 2, wherein data for one track is formed by storing data in a buffer memory. (4) storing data reproduced N times by reproducing one track of data recorded on a disk using a disk rotation speed corresponding to N times a predetermined data transfer rate in a buffer memory for N tracks; 3. The data reproducing method for a disk device according to claim 2, wherein data processing is performed on the stored data for N tracks to form data for one track.