JPH08315519A - Recorder/player - Google Patents

Abstract

PURPOSE: To attain a stabilized reading operation by storing an area where the reading operation has been executed predetermined times or more under control of a retry control means and writing data read out therefrom into that area again. CONSTITUTION: During reproducing operation, information on a magnetooptic disk 1 is detected through an optical head 3 and fed to an RF amplifier 7. The amplifier 7 processes the information to extract a reproduction RF signal which is delivered to an encoder/decoder section 14. Error signal is sent to a servo circuit 9 while group information is sent to an address decoder 10 and demodulated. The decoded address information is sent to a system controller 11 comprising a microcomputer. The data written in a buffer memory 13 is read out at such rate as the reproduced data is transferred at a predetermined rate and sent to the encoder/decoder section 14. The data is then sent out, in the form of a reproduced voice output signal, from a terminal 16 and outputted as a voice.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing apparatus capable of recording / reproducing data such as music on a disc-shaped recording medium.

[0002]

2. Description of the Related Art There are known data rewritable magneto-optical disks on which a user can record music data and the like. Among such disk media, a disk memory having a vibration-proof function improved by using a buffer memory is known. Has been realized.

That is, at the time of reproduction, the audio data read from the magneto-optical disk is intermittently written into the buffer memory at a high speed, while the audio data is continuously read from the buffer memory at a low speed and demodulated as an audio reproduction signal. To process. At this time, a certain amount of data is always stored in the buffer memory, so even if a track jump occurs due to external vibration, etc., and the data reading from the magneto-optical disk is temporarily interrupted, the buffer memory The audio data can be continuously read from, and the reproduced audio is output without interruption. Further, at the time of recording, input data is once continuously written in a buffer memory at a low speed rate, and this is intermittently read at a high speed rate and supplied to a recording head for recording on a disk.

[0004]

By the way, if the data cannot be normally read from the disk due to the provision of such a buffer memory for some reason, the read operation (retry) is performed again for that portion. (Operation) is obtained, and this retry operation can realize an appropriate reproduction operation in response to the occurrence of a read error. Especially in the recorded data, there may be a part where a read error occurs frequently in the read operation. Even if a read error occurs in such a part, the retry operation realizes proper reproduction. To be done.

However, if the retry operation is not successful and the number of retries increases and the retry operation takes a long time, the amount of data stored in the buffer memory decreases accordingly. Needless to say, this leads to deterioration of the vibration resistance function. In addition, the retry operation is achieved only by completing within the time margin according to the amount of data accumulated in the buffer memory, so that proper reproduction is realized, and the retry operation is repeated until the data is no longer accumulated in the buffer memory. If the operation is continued, noise sound due to the read error will be output.

[0006]

The present invention has been made in view of the above problems, and a read error may occur for some reason, which is caused by recorded data rather than disturbance. It is an object of the present invention to eliminate the read error frequency when the read error frequency is high.

Therefore, when an error occurs in the read operation by the read means, the read means is provided with retry control means for executing the read operation again for the area on the recording medium in which the error has occurred, and the retry control is performed. A rewriting control in which an area on the recording medium in which the reading operation has been performed a predetermined number of times or more is stored by the control of the means, and the reproduction data from the area can be rewritten in the area by the writing means. Means should be provided.

[0008]

For example, in the area where the retry operation has been executed a predetermined number of times or more, the reading becomes unstable due to the recorded data, and it is considered that reading errors occur frequently.
By rewriting the data in the area using the data properly read from the area, a stable read operation can be realized thereafter.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the recording / reproducing apparatus of the present invention is shown in FIG.
~ It demonstrates in the following order using FIG. 1. Configuration of recording / reproducing apparatus 2. Cluster format 3. Example of rewriting operation 4. Processing example for rewriting operation

[0010] 1. Configuration of Recording / Reproducing Apparatus FIG. 1 is a block diagram of a main part of a recording / reproducing apparatus using a magneto-optical disk (mini disk) as a recording medium according to an embodiment of the present invention. The magneto-optical disk 1 is used as a medium capable of recording audio data, and is rotated by a spindle motor 2 during recording / reproduction. The optical head 3 irradiates the magneto-optical disk 1 with a laser beam at the time of recording / reproducing, thereby performing an operation as a head at the time of recording / reproducing. That is, at the time of recording, a high-level laser output for heating the recording track to the Curie temperature is provided,
Further, at the time of reproduction, a relatively low level laser output for detecting data from reflected light is produced by the magnetic Kerr effect.

For this reason, the optical head 3 is equipped with a laser diode as a laser output means, an optical system including a polarization beam splitter and an objective lens, and a detector for detecting reflected light. The objective lens 3a is 2
It is held by a shaft mechanism 4 so as to be displaceable in the disk radial direction and the direction in which it comes in and out of contact with the disk, and the entire optical head 3 is movable by a sled mechanism 5 in the disk radial direction. The magnetic head 6a is arranged at a position facing the optical head 3 with the magneto-optical disk 1 interposed therebetween. The magnetic head 6a operates to apply a magnetic field modulated by the supplied data to the magneto-optical disk 1. The magnetic head 6a is movable in the disk radial direction by the sled mechanism 5 together with the optical head 3.

By the reproducing operation, the information detected from the magneto-optical disk 1 by the optical head 3 is supplied to the RF amplifier 7. The RF amplifier 7 calculates a reproduction RF signal, a tracking error signal, a focus error signal, groove information (absolute position information recorded as a pre-groove (wobbling groove) on the magneto-optical disk 1) and the like by calculating the supplied information. Extract. Then, the extracted reproduction RF signal is supplied to the encoder / decoder unit 8. The tracking error signal and the focus error signal are supplied to the servo circuit 9, and the groove information is supplied to the address decoder 10 for demodulation. The address information decoded from the groove information and the address information recorded as data and decoded by the encoder / decoder unit 8 are supplied to the system controller 11 configured by a microcomputer.

The servo circuit 9 supplies the supplied tracking error signal and focus error signal, the track jump command and the access command from the system controller 11,
Various servo drive signals are generated based on rotational speed detection information and the like to control the biaxial mechanism 4 and the sled mechanism 5 for focus and tracking control, and to control the spindle motor 2 to a constant linear velocity (CLV).

The reproduced RF signal is sent to the encoder / decoder unit 8
At EFM demodulation, decoding processing such as CIRC is performed, and the data is temporarily written in the buffer memory 13 by the memory controller 12. The reading of data from the magneto-optical disk 1 by the optical head 3 and the reproduction data transfer from the optical head 3 to the buffer memory 13 are performed at 1.41 Mbit / sec.

The data written in the buffer memory 13 is read out at a timing when the reproduction data is transferred at 0.3 Mbit / sec, and is supplied to the encoder / decoder section 14. Then, reproduction signal processing such as decoding processing for audio compression by the modified DCT processing is performed, and the D / A converter 1
An analog signal is given by 5. Then, it is supplied as a reproduced sound output signal from the terminal 16 to a part such as a power amplifier and is outputted as sound from a speaker or the like.

Writing / reading of data to / from buffer memory 13 is performed by addressing by memory controller 12 under the control of a write pointer and a read pointer. During such playback, the write pointer (write address) is incremented at a timing of 1.41 Mbit / sec as described above, while the read pointer (read address) is incremented at a timing of 0.3 Mbit / sec. Therefore, due to the difference between the bit rates of writing and reading, a certain amount of data is stored in the buffer memory 13. When the full capacity of data is stored in the buffer memory 13, the increment of the write pointer is stopped, and the data read operation from the magneto-optical disk 1 by the optical head 3 is also stopped. However, the read pointer R
Since the increment of is continuously executed, the reproduced voice output is not interrupted.

Thereafter, only the read operation is continued from the buffer memory 13, and at some point the buffer memory 13
Assuming that the amount of data stored therein is equal to or less than the predetermined amount, the data reading operation by the optical head 3 and the increment of the write pointer are restarted again, and the data is again stored in the buffer memory 13.

By outputting the reproduced sound signal via the buffer memory 13 as described above, the reproduced sound output is not interrupted even if the tracking is missed due to disturbance or the like, and the data accumulation remains. By accessing to the correct tracking position and restarting the data reading while the operation is in progress, the operation can be continued without affecting the reproduction output. That is, the vibration resistance function can be remarkably improved. In other words, the read operation by the optical head 3 can be retried while the reproduction output is continued by the accumulated data in the buffer memory 13.

When the recording operation is performed on the magneto-optical disk 1, the audio signal input from the terminal 17 is A /
It is supplied to the D converter 18. The A / D converter 18 converts the digital data into 44.1 KHz sampling and 16-bit quantized data, and then the encoder / decoder unit 14
And is subjected to audio compression encoding processing. That is, the modified DCT processing compresses the data amount to about 1/5.

The recording data compressed in the encoder / decoder section 14 is once written in the buffer memory 13 by the memory controller 12, and is read at a predetermined timing and sent to the encoder / decoder section 8. Then, the encoder / decoder unit 8 performs encoding processing such as CIRC encoding and EFM modulation, and then supplies the magnetic head driving circuit 6.

The magnetic head drive circuit 6 supplies a magnetic head drive signal to the magnetic head 6a according to the encoded recording data. That is, the N or S magnetic field is applied to the magneto-optical disk 1 by the magnetic head 6. Further, at this time, the system controller 11 supplies a control signal to the optical head 3 so as to output a laser beam of a recording level.

The operation unit 19 is provided with a recording key, a reproduction key, a stop key, an AMS key, a search key and the like so as to be operated by the user. The display unit 20 displays various information such as the total playing time of the disc, the progress time during reproduction and recording, and various displays such as the track number, the operating state, and the operating mode under the control of the system controller 11.

RA in the system controller 11
The M11a is used as a work memory for various control calculations, and in particular, is used in this embodiment to store the address of a target area (cluster) for rewriting processing described later.

2. Cluster Format Here, a unit called a cluster will be described. The format of a cluster which is a unit of recording operation in the mini disk system is shown in FIG. As a recording track in the mini disk system, a cluster CL is used as shown in FIG.
Are continuously formed, and one cluster is the minimum unit for recording. One cluster corresponds to 2 to 3 rounds of tracks.

One cluster CL is composed of sectors S _FC ~
And 4 sector sub-data area that is S _FF, is formed from a main data area of 32 sectors indicated as sectors S ₀₀ to S _1F. One sector is a data unit formed of 2352 bytes. The 4-sector sub-data area is used as sub-data or a linking area, and the TOC data, audio data, etc. are recorded in the 32-sector main data area. The address is recorded for each sector.

The sectors are further subdivided into units called sound groups, and two sectors are divided into 11 sound groups. That is, as shown in the figure, the sound groups SG _{00 to} SG _0A are included in two consecutive sectors, an even sector such as the sector S ₀₀ and an odd sector such as the sector S ₀₁ . One sound group consists of 424 bytes,
The amount of audio data is equivalent to 11.61msec. In one sound group SG, data is recorded separately for the L channel and the R channel. For example, the sound group SG ₀₀ is composed of L channel data L0 and R channel data R0, and the sound group SG ₀₁
Is composed of L channel data L1 and R channel data R1. It should be noted that 212 bytes that are the data area of the L channel or the R channel are called a sound frame.

3. Rewriting Operation Example Here, the rewriting operation, which is a characteristic operation in the recording / reproducing apparatus of the present embodiment, will be described with an example. The rewrite operation is an operation of rewriting data after a reproduction is completed for a cluster having a portion in which a read error occurs during reproduction and appropriate data is read by several retry operations.

For example, when a read error occurs in reading a certain sector, but if proper data can be read by one or two retry operations, it is possible that the read error is caused by external vibration. high. Therefore, it can be determined that the recorded data itself has no problem. However, for example, when the data can be finally read normally by three or more retry operations, there is a high probability that the data itself has a problem rather than external vibration or the like. In such a case, there is a high possibility that a read error will occur in the same sector during the next reproduction.

Therefore, in the present embodiment, the cluster number (cluster address) of the cluster which is judged to have a problem in the data itself is stored during the reproduction, and the data of the crater is read again at the end of the reproduction to make it appropriate. When such data is read, the data is rewritten to the cluster.
In other words, the problem of the data itself, which causes the read error,
It is intended to be solved by rewriting the data.

FIG. 2 shows an operation example. Now, it is assumed that reproduction is performed on the disc 1 between addresses Ad _{1 and} Ad ₂ . When the optical head 3 is reproducing from the address Ad _{1 as} shown in the figure, a read error occurs in a read operation for a certain sector (sector Sn) in a certain cluster (cluster CLx). And Here, the system controller 11 causes the operation by the optical head 3 to execute the read retry of the sector Sn.

However, as shown in the figure, it is assumed that the first retry fails, the retry is repeated, and the third retry also fails, and the data is finally read normally by the fourth retry. At this time, the system controller 11 continues to read the subsequent sectors after the retry, but stores the address (CLx) of the cluster including the sector which has been retried three times or more.

It is assumed that the reading is continued as shown after that, and the reproduction is ended when the reproduction operation reaches the address Ad ₂ . Then, the system controller 11 causes the optical head 3 to access the head of the cluster CLx,
The data of the cluster CLx is read as indicated by. Then, it is assumed that a read error occurs again as indicated by the sector Sn, and the data in the sector Sn is normally read by performing the retry twice. After that, when the data up to the end of the cluster CLx is read and all the data of the cluster CLx is fetched in the buffer memory 13, the system controller 11 subsequently accesses the head position of the cluster CLx with the optical head 3 and the magnetic head 6a again. And the buffer memory 1 as shown in
The data read in 3 is recorded in the area of the cluster CLx.

When the recording operation on the cluster CLx is completed, the operation is completed. at this point,
As the data of the cluster CLx, the content of the data remains as it is, but since it has been newly rewritten, some problems that may have existed in the sector Sn are solved. Therefore, during the subsequent reproduction, the occurrence of a read error in the same sector Sn can be eliminated.

4. Processing Example for Rewriting Operation Processing of the system controller 11 for realizing such a rewriting operation will be described with reference to FIGS. 3 and 4. First, during the reproducing operation, the system controller 11 performs the processing shown in FIG. That is, the process proceeds from step F101 to step F102 until the reproduction operation is completed, and the reading of data from the disk 1 by the optical head 3 is executed. The read operation is intermittently performed at a high speed rate according to the storage amount of the buffer memory 13 as described above.

If no reading error occurs during the data reading process, the process proceeds from step F103 to F104, resets the retry counter RCT, and steps F101 to F1.
The procedure returns to 02 to read the next sector. When a read error occurs when reading a certain sector data, the process proceeds from step F103 to F105, and the sector data is reread, that is, the read retry operation is executed. At this time, the retry counter RCT is incremented (F10
6).

If a read error occurs again due to the read retry, the process returns from step F108 to step F105 to repeat the read retry. If the number of retries reaches 10, even if the data read by the 10th retry is an error,
Let it be valid data. That is, when a positive result is obtained in step F107, the process proceeds to step F104, the retry counter RCT is reset, and in step F102, the reading of the next sector data starts.

When normal data can be read by several retries less than 10 times, the process is started from step F108.
Go to F109 and check the retry counter RCT. If the retry counter RCT is not 3 or more, that is, if the data can be read normally by one or two retry operations, the process directly proceeds to step F104, the retry counter RCT is reset, and the next step F102 is performed. Move on to reading of sector data.

On the other hand, in step F109, the retry counter R
When CT is determined to be 3 or more, the number (cluster address) of the cluster including the sector for which the read retry is performed is stored. That is, the system controller 11
Judges that the sector that could be read by the retry operation 3 to 9 times is unstable due to some problem in the data itself, and rewrites the cluster including the sector after the end of reproduction. The cluster address for executing the operation is stored in the RAM 11a.

When the reproducing operation is completed, the process is step F1.
Proceed from 01 to F111 to start rewriting processing. This rewriting process is shown in detail in FIG. First, the system controller 11 searches the RAM 11a to obtain a cluster address to be rewritten (F201).

If no cluster address to be rewritten is stored, the rewriting operation is of course unnecessary, and the processing is ended from step F202 without doing anything. On the other hand, if there is a cluster address to be rewritten, the system controller 11 causes the optical head 3 to access the cluster address and read the data of the cluster. Also in this case, if a read error occurs, normal data is read by the retry operation (F203, F204). This processing corresponds to the operation of FIG. Regarding the retries when it is determined in step F204 that there is a read error, it is preferable to limit the number of retries in order to prevent the loop from actually becoming an infinite loop.

When the data reading is completed for the cluster and the cluster data is loaded into the buffer memory 13, the data held in the buffer memory 13 is written again in the area of the cluster address of the disk 1 (F205 ). This processing corresponds to the operation of FIG. When the rewriting operation for such a rewriting operation target cluster is completed, the RAM 11a is checked again to search for another rewriting operation target cluster, and if it exists, the rewriting operation is similarly executed. If it does not exist, the processing ends.

By the above processing, the recording / reproducing apparatus of this embodiment realizes the rewriting operation as illustrated in FIG.
As a result, even if there is a portion where the reading becomes unstable due to the data itself, it will be eliminated, and the number of read errors and the required number of read retry operations will be greatly reduced. Will be reduced. This does not unnecessarily lower the anti-vibration function of the buffer memory 13, and the performance of the device is improved.

By the way, after the rewriting operation is performed as described above, the data check may be performed by further reading the data from the cluster. Then, for example, if the number of retries is large and the data is properly read within 2-3 times, the check is OK. However, if a data read error occurs even after retrying a few times, it is considered that the error is caused by, for example, an irreparable scratch, and the area is damaged in the management information (TOC) of the disk 1. It is possible to perform processing such as registration as an area or registration as a writable free area.

In the rewriting operation of the embodiment,
After the playback is finished, the data of the target cluster is read again and the read data is written.
When the cluster is retried several times during playback, when the cluster is designated as the rewrite operation target, the data itself read at that time is also stored, and the stored data is written as it is after the playback is completed. By doing so, the processing after the end of reproduction can be completed in a short time. That is,
The operation of FIG. 2 can be eliminated. Also,
The rewrite operation target is designated as the cluster in which the retry operation is executed 3 to 9 times, but of course, various other designated conditions can be considered.

[0045]

As described above, in the recording / reproducing apparatus of the present invention, in the area where the retry operation is executed a predetermined number of times or more, the reading becomes unstable due to the recorded data, and the reading error frequently occurs. Then, the determination is made, and the data properly read from the area is used to rewrite the data in the area. Therefore, a stable read operation can be realized for the area thereafter. As a result, it is possible to obtain the effect that a stable reproducing operation is realized without impairing the vibration resistance performance.

[Brief description of drawings]

FIG. 1 is a block diagram of a recording / reproducing apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a rewriting operation of the embodiment.

FIG. 3 is a flowchart of a process for a rewriting operation of the embodiment.

FIG. 4 is a flowchart of a process for a rewriting operation of the embodiment.

FIG. 5 is an explanatory diagram of a cluster format of the mini disk system.

[Explanation of symbols]

 1 Disk 3 Optical Head 6a Magnetic Head 9 Servo Circuit 11 System Controller 11a RAM 12 Memory Controller 13 Buffer Memory

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location G11B 11/10 581 9296-5D G11B 11/10 581D 586 9296-5D 586E 19/04 501 19/04 501D 27/08

Claims (1)

[Claims] 1. A reading means capable of reading data from a recording medium, a writing means capable of writing data to a recording medium, and the reading operation when an error occurs in the reading operation by the reading means. The means for storing the area on the recording medium in which the read operation is performed a predetermined number of times or more under the control of the retry control means. The recording / reproducing apparatus is characterized by further comprising rewriting control means capable of rewriting the reproduced data from the area to the area by the writing means.