JPH0896537A - Access mechanism transfer method, reproducing apparatus, and recording apparatus - Google Patents

Abstract

(57) [Abstract] [Purpose] To suppress the occurrence of gear noise in the sled mechanism driven at high speed due to access operations during reproduction and recording as much as possible so as not to interfere with music listening. [Structure] In the access operation during reproduction, when the amount of data stored in the buffer RAM 13 is equal to or larger than a predetermined value Th (FIG. 7A), low speed drive of the sled motor or low speed access by track jump is performed. When the data storage amount is equal to or less than the predetermined value Th (FIG. 7B), the high speed access is performed by the high speed drive of the sled motor. Further, in the access operation at the time of recording, when the data storage amount is equal to or less than the predetermined value set corresponding to the recording, the low speed access is performed, and when the data storage amount is equal to or more than the predetermined value, the high speed access is performed. .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reproducing device for a disc-shaped recording medium, a recording device, and a method for transferring an access mechanism in these devices.

[0002]

2. Description of the Related Art Disc rewritable disc-shaped recording media on which a user can record music data and the like are known. In such disc media, there are already recorded areas such as music and other areas. Data area for managing recording area (user TOC, UT
OC) is provided, and this management data is also rewritable according to operations such as recording, editing, and erasing.

When recording a certain piece of music, for example, the recording device searches the U-TOC for an unrecorded area on the disc and records the audio data there. . Further, in the reproducing apparatus, the area in which the music (track) to be reproduced is recorded is U
-From the TOC, the area is accessed and the reproducing operation is performed.

By the way, in recordable disc media such as magneto-optical discs (MO discs), DA
Random access is extremely easy as compared with tape-shaped recording media such as T and compact cassette tapes, and therefore, recording is performed in order from the first track to the n-th track from the inner circumference side to the outer circumference side on the disk. No need. That is, even if each music piece is physically recorded at different positions on the disc, the first track to the nth track are recorded.
As long as the recorded address of each music up to the track is managed, the music can be reproduced in the correct music order.

Further, for example, one track (song) does not necessarily have to be recorded in continuous parts (a part means a part in which physically continuous data is recorded). There is no problem even if the data is discretely recorded on a disc and divided into a plurality of parts. Especially, the data read from the magneto-optical disk is temporarily stored in the buffer RAM at a high speed,
In a system that reads data at a low speed from the device and demodulates it as an audio reproduction signal, even if data reading from the magneto-optical disk is temporarily interrupted due to access between parts, the reproduced audio will not be interrupted. Can be output.

Therefore, if the recording / reproducing operation in the part and the access operation (the access operation which is completed within the reproducible time due to the amount of data accumulation caused by the difference between the write rate and the read rate of the buffer RAM) are repeated, 1 Even if the track of one music is divided into a plurality of parts and physically divided, it is possible to prevent the recording / playback of the music from being hindered.

[0007] For example the first piece of music part M ₁ as shown in FIG. 19, the second piece of music is physically continuously recorded on one part as part M _2, 4th music, 5 songs As shown in parts M _{4 (1) to} M _{4 (4)} and M _{5 (1) to} M _{5 (2)} , it is also possible to record the data by dividing it into a plurality of parts on the disc. (Note that FIG. 19 is a schematic illustration only, and in reality, one part often covers several to several hundreds of tracks or more.)

When recording or erasing music on a magneto-optical disk is repeated, vacant areas on the tracks are irregularly generated due to the difference in the playing time of the recorded music or the playing time of the erased music. By executing the discrete recording in this way, it becomes possible to record, for example, a music longer than the erased music by utilizing the erased portion, and by repeating recording / erasing, the data recording area Waste is eliminated. It should be noted that what is recorded is not necessarily a “song”, and any sound signal is included, but in the present specification, a song is recorded as one unit of data (track) that is continuous in terms of content. Will be explained.

Of course, for such a disc,
During recording, recording must be continued while accessing a plurality of unrecorded parts, and during reproduction, the parts must be accessed so that one music piece can be correctly and continuously reproduced. Data for connecting parts (for example, M _{4 (1) to} M _{4 (4)} ) in one music necessary for this purpose and data indicating an unrecorded area are recorded or erased as described above. U-TOC rewritten every operation
It is stored as information, and the recording / reproducing apparatus uses this U-
By reading the TOC information and accessing the head, the recording / reproducing operation is controlled appropriately.

As an access mechanism for accessing the head, an objective lens of the optical head is driven by a tracking error signal obtained from track guide information such as a pit row and a groove to track an optical spot, for example. In addition to the biaxial mechanism for controlling, a sled mechanism for displacing the relative position between the entire optical head and the disc surface in the disc radial direction is provided.

As the sled mechanism, there are known a sled mechanism that moves the entire optical head with respect to the disc and a sled mechanism that moves the turntable on which the disc is mounted with respect to the positionally fixed optical head. Actually, a gear mechanism is provided between the sled motor and the optical head or the turntable, and the optical head or the turntable is transferred by controlling the rotation of the sled motor.

When the head access operation is performed during reproduction or recording of the optical disk, for example, when the number of jump tracks increases, not only the movement of the objective lens by the biaxial mechanism but also the optical head or turn by the sled mechanism is performed. Control such as moving the table following the table is performed.

[0013]

By the way, during the access operation as described above, the thread is usually arranged so that the optical head reaches the next access position as quickly as possible regardless of the data storage state of the buffer RAM. I try to rotate the motor as fast as possible. However, when the sled motor is rotationally driven at a high speed in this way, the noise generated by the gears accompanying it becomes so large that it cannot be ignored. Therefore, if, for example, the parts are accessed while actually listening to a song while simultaneously playing back the disc or monitoring the source being recorded, this gear noise will be annoying to the user. There is a problem that comes. Especially, in music such as classical music where a relatively large number of quiet parts appear in the music, gear noise becomes so noticeable that the user cannot enjoy the music without being immersed in it.

[0014]

Therefore, in order to solve the above-mentioned problems, the present invention suppresses the occurrence of gear noise of the thread mechanism due to the access operation at the time of reproduction and recording as much as possible to prevent the music from being listened to. The purpose is not to become.

Therefore, a disk-shaped reproducing device having a reading head part for reading data from the disk-shaped recording medium and a memory part for temporarily storing the data read by the reading head part and outputting it as reproduced data. As a transfer method of an access mechanism for accessing the read head unit to a desired access target position of the recording medium,
The transfer speed at the time of access is changed based on the amount of data stored in the memory unit and / or the time required for the reading head unit to move to the access target position. And, as the constitution of the reproducing apparatus which realizes the above-mentioned transfer method of the access mechanism,
Based on the determination result of the amount of data stored in the memory unit, the control unit that changes the transfer speed of the access mechanism is provided. Alternatively, a control unit for varying the transfer speed of the access mechanism is provided based on the result of calculating the time required for the read head unit to move to the access target position. Alternatively, a control unit for varying the transfer speed of the access mechanism is provided based on the determination result of the data storage amount of the memory unit and the calculation result of the time required for the read head unit to move to the access target position. I decided.

Further, as the access mechanism, a first access mechanism for displacing the relative position between the objective lens of the read head section and the disk-shaped recording medium, and an objective lens and disk-shaped recording larger than the first access mechanism. A second access mechanism capable of displacing the relative position with respect to the medium is provided, and the control unit includes the first access mechanism and the second access mechanism.
By changing the access mechanism, the transfer speed at the time of access can be changed. Alternatively, the control unit changes the driving voltage level and / or the driving time for operating the second access mechanism to change the transfer speed at the time of access.

Further, there is provided a memory section for temporarily storing the input data and outputting it as recording data, and a recording head section capable of recording the recording data output from the memory section on a disc-shaped recording medium. As a transfer method of an access mechanism for accessing the recording head unit to a desired access target position of a disk-shaped recording medium in a recording apparatus, a data storage amount of a memory unit and / or the recording head unit is moved to an access target position. Based on the time required for the transfer, the transfer speed at the time of access is made variable. As a configuration of the recording apparatus that realizes the above-described access mechanism transfer method, a control unit that changes the transfer speed of the access mechanism based on the determination result of the data storage amount of the memory unit is provided. Alternatively, control means for varying the transfer speed of the access mechanism is provided based on the result of calculation of the time required for the recording head unit to move to the access target position. Alternatively, control means is provided for varying the transfer speed of the access mechanism based on the result of determination of the amount of data stored in the memory section and the result of calculating the time required for the recording head section to move to the access target position. I decided.

Further, as the access mechanism, first access means for displacing the relative position between the objective lens of the recording head section and the disc-shaped recording medium, and the objective lens and the disc-shaped recording medium larger than the first access mechanism are provided. And a second access mechanism capable of displacing the relative position between the first access mechanism and the second access mechanism.
By changing the access mechanism, the transfer speed at the time of access can be changed. Alternatively, the control unit changes the drive voltage level and / or the drive time for operating the second access mechanism to change the transfer speed at the time of access.

[0019]

According to the above construction, in the reproducing apparatus, the data in the memory is stored based on the amount of data stored in the memory, the time required to move to the access target position, and the information obtained by comparing the two information. As long as there is enough storage capacity, the thread mechanism is driven at a low speed at the time of access as much as possible, or a low-speed access is performed by performing an access operation by a track jump. Further, in the recording device, based on the same information as above, as long as there is a free space in the memory data, it is controlled so as to be as slow as possible access, but this is caused to move the thread mechanism at high speed. Gear noise can be reduced.

[0020]

EXAMPLES As examples of the present invention, a recording / reproducing apparatus corresponding to a magneto-optical disk as a recording medium will be described below, and the description will be made in the following order. 1. Configuration of recording / reproducing apparatus 2. P-TOC sector 3. U-TOC sector 4. Area structure of disc 5. Access operation during reproduction (first to fourth embodiments) 6. Access operation during recording (fifth to seventh embodiments)

<1. Configuration of Recording / Reproducing Apparatus> FIG. 1 is a block diagram of a main part of the recording / reproducing apparatus of the embodiment. In FIG. 1, reference numeral 1 denotes a magneto-optical disc on which audio data is recorded, for example, and schematically shows a state in which it is loaded from the disc insertion portion 32. The magneto-optical disk 1 is rotationally driven by a spindle motor 2. Reference numeral 3 denotes an optical head for irradiating the magneto-optical disk 1 with laser light at the time of recording / reproducing, which provides a high level laser output for heating the recording track to the Curie temperature at the time of recording,
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.

Therefore, the optical head 3 is equipped with a laser diode as a laser output means, an optical system including a deflecting beam splitter, an objective lens and the like, and a detector for detecting reflected light. The objective lens 3a is held by the biaxial mechanism 4 so as to be displaceable in the disc radial direction and the direction in which the disc moves toward and away from the disc.

Reference numeral 6a denotes a magnetic head for applying a magnetic field modulated by the supplied data to the magneto-optical disk, which is arranged at a position facing the optical head 3 with the magneto-optical disk 1 interposed therebetween. The optical head 3 is movable in the disk radial direction by a sled mechanism 5.

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 the supplied RF signal, tracking error signal, focus error signal, absolute position information (absolute position information recorded as pre-groove (wobbling groove) on the magneto-optical disc 1) by processing the supplied information. To 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 absolute position information is supplied to the address decoder 10.

The servo circuit 9 generates various servo drive signals based on the supplied tracking error signal, focus error signal, track jump command, seek (access) command, rotation speed detection information of the spindle motor 2, etc. from the system controller 11. Then, the biaxial mechanism 4 and the sled mechanism 5 are controlled to perform focus, tracking, access control, etc., and the spindle motor 2 is controlled to a constant angular velocity (CAV) or a constant linear velocity (CLV). For example, for the sled mechanism 5, the servo circuit 9
The sled drive voltage SD for rotating the sled motor is further supplied, and the tracking drive signal TD for displacing and driving the objective lens 3a is supplied to the biaxial mechanism 4.

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

The data written in the buffer RAM 13 is read out at the timing when the reproduction data is transferred at 0.3 Mbit / sec, and is supplied to the encoder / decoder section 14. Then, a reproduction signal process such as a decoding process for the audio compression process is performed to obtain an output digital signal.

The output digital signal is converted into an analog signal by the D / A converter 15, and the analog line output terminal 1
6A is supplied. Alternatively, it is directly supplied to the digital output terminal 16D without being converted to analog.

Here, writing / reading of data to / from the buffer RAM 13 is performed by being addressed by the memory controller 12 under the control of the write pointer and the read pointer. The write pointer (write address) has been described above. As described above, the read pointer (read address) is incremented at a timing of 1.41 Mbit / sec, while the read pointer (read address) is 0.3 Mbit / se.
Since it is incremented at the timing of c, due to the difference between the bit rates of writing and reading, the buffer RA
A certain amount of data is stored in M13.
When the full capacity of data is accumulated in the buffer RAM 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, since the read pointer R is continuously incremented, the reproduced voice output is not interrupted.

Thereafter, only the read operation is continued from the buffer RAM 13, and at some point the buffer RAM 13
Assuming that the amount of data stored therein is equal to or less than a 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 RAM 13.

By outputting the reproduced sound signal via the buffer RAM 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 the correct tracking position and restarting the data reading, the operation can be continued without affecting the reproduction output. That is, the seismic resistance function can be significantly improved.

In FIG. 1, address information output from the address decoder 10 and subcode data used for control operation are supplied to a system controller 11 composed of a microcomputer via an encoder / decoder section 8 and various kinds of data are supplied. Used for control operation. Further, a PL for generating a bit clock for recording / reproducing operation
The lock detection signal of the L circuit and the monitor signal of the missing state of the frame synchronization signal of the reproduction data (L and R channels) are also supplied to the system controller 11.

When the recording operation is performed on the magneto-optical disk 1, the analog code is connected to the analog input terminal 17A from another device by an audio cord connected to the analog input terminal 17A or an audio optical cable connected to the digital input terminal 17D. Alternatively, a digital audio signal is supplied.

Digital data with digital input terminal 17D
The audio signal sent to is directly supplied to the encoder / decoder unit 14. The analog audio signal input from the analog input terminal 17A is converted into digital data by the A / D converter 18 and then supplied to the encoder / decoder unit 14.

The encoder / decoder section 14 performs audio compression encoding processing on the input digital audio signal. The recording data compressed by the encoder / decoder unit 14 is once written in the buffer RAM 13 by the memory controller 12, is also read at a predetermined timing, and is sent to the encoder / decoder unit 8. Then, the encoder / decoder unit 8 performs CIRC encoding,
It is supplied to the magnetic head drive circuit 6 after being subjected to encoding processing such as EFM modulation.

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 magnetic head 6a applies an N or S magnetic field to the magneto-optical disk 1. At this time, the system controller 11 also supplies a control signal to the optical head so as to output a laser beam of a recording level.

Reference numeral 19 denotes an operation input section provided with keys used for user operation, which includes playback / fast forward / fast rewind / AM.
There are provided operation keys for S search / stop / recording, operation keys for setting various operation modes, and operation keys for performing various editing processes. Reference numeral 20 denotes a display unit such as a liquid crystal panel, which displays the operating state, mode state, reproduction progress time, recording progress time, track number, etc. under the control of the system controller 11.

By the way, when the recording / reproducing operation is performed on the disc 1, the management information recorded on the disc 1, that is, P-TOC (pre-mastered TOC), U-.
The TOC (user TOC) is read out, and the system controller 11 determines the address of the part to be recorded on the disc 1 and the address of the part to be reproduced according to the management information. It is held in the buffer RAM 13. Therefore, the buffer RAM
In the area 13, the recording data / playback data buffer area and the area for holding the management information are divided and set.

Then, the system controller 11 reads out these management information by executing a reproducing operation on the innermost circumference side of the disc on which the management information is recorded when the disc 1 is loaded, and stores it in the buffer RAM 13. It is possible to refer to the recording / reproducing operation for the disc 1 thereafter.

The U-TOC is edited and rewritten according to the recording and erasing of data, but the system controller 11 stores this editing process in the buffer RAM 13 every time the recording / erasing operation is performed. The TOC information is written and the U-TOC area of the disc 1 is rewritten at a predetermined timing according to the rewriting operation.

<2. P-TOC Sector> Now, as the audio data sector recorded in the sector data form on the disc 1, and the management information for managing the recording / reproducing operation of the audio data, the P-TOC sector will be described first. As the P-TOC information, area designation such as a recordable area (recordable user area) of the disc and management of the U-TOC area are performed. When the disc 1 is a premastered disc which is a read-only optical disc, it is possible to manage the music recorded in the ROM by the P-TOC.

The format of the P-TOC is shown in FIG.
FIG. 2 shows P-recorded repeatedly in an area for P-TOC (for example, ROM area on the innermost side of the disc).
One sector (sector 0) of TOC information is shown. It should be noted that the description of the P-TOC format sector 1 and subsequent sectors will be omitted.

The data area of the sector of P-TOC (4 bytes x 588, 2352 bytes) has all 0s at the head position.
Alternatively, a synchronization pattern composed of all-byte 1-byte data is provided. Next, 4 bytes of an address indicating a cluster address and a sector address are added to form a header.

Further, an identification ID by an ASCII code corresponding to the character "MINI" is added at a predetermined address position following the header, indicating that it is a P-TOC area. Furthermore, the disc type, recording level, song number of the first song recorded (First TNO), song number of the last song (Last TNO), lead-out start address LO _A , power cal area start address P.
C _A, start address UST _A of U-TOC (data area of U-TOC sector 0 in FIG. 3 to be described later), a start address RST _A, etc. recordable area (recordable user area) is recorded.

Next, there is prepared a correspondence table instruction data section having table pointers (P-TNO1 to P-TNO255) for associating recorded music pieces and the like with a parts table in a management table section described later.

Then, in the area subsequent to the correspondence table instruction data portion, (01h) to (FF) corresponding to the table pointers (P-TNO1 to P-TNO255) in the correspondence table instruction data portion.
A management table section provided with up to 255 parts tables up to (h) is prepared (herein, "h"
Numerical values with are so-called hexadecimal notation). In each part table, the start address, the end address, and
And mode information (track mode) of the parts (tracks) can be recorded. The parts mean track portions in which temporally continuous data are recorded physically continuously, for example, M ₁ and M in FIG.
It is the track portion shown as _{4 (4)} .

The mode information of the track in each parts table records, for example, information as to whether the part is set to overwrite inhibition or data copy inhibition, whether it is audio information, or monaural / stereo type. Has been done.

In each part table from (01h) to (FFh) in the management table section, the contents of the part are indicated by the table pointers (P-TNO1 to P-TNO255) in the corresponding table instruction data section. That is, for the first piece of music, a certain parts table (for example, (01h) is used as the table pointer P-TNO1. However, the table pointer is actually the byte position in the P-TOC sector 0 by the predetermined arithmetic processing. Is recorded), in which case the start address of the parts table (01h) is the start address of the recording position of the first piece of music, and similarly the end address is The end address is the position where the first piece of music is recorded. Further, the track mode information becomes information about the first music piece.

Similarly, for the second piece of music, the parts table indicated by the table pointer P-TNO2 (eg (02h))
The start address, end address, and track mode information of the recording position of the second tune are recorded in.

Similarly, since the table pointers up to P-TNO255 are prepared, it is possible to manage up to the 255th song on the P-TOC. And like this P-T
By forming the OC sector 0, it is possible to access and reproduce a predetermined music, for example, during reproduction.

In the case of a recordable / reproducible magneto-optical disk, since there is no so-called pre-mastered music area, the above-mentioned correspondence table instruction data section and management table section are not used (these are U-described later). TO
(It is managed by C), so each byte is all "00h". However, for pre-mastered type discs in which all songs are recorded in ROM form (pit form), and hybrid type discs having both ROM area and magneto-optical area as areas for recording songs, etc., The correspondence table instruction data section and the management table section are used to manage the music in the ROM area.

<3. U-TOC sector> followed by UT
The OC will be explained. FIG. 3 shows a format of one sector (sector 0) of the U-TOC, and mainly records management information about a song recorded by the user and an unrecorded area (free area) in which a new song can be recorded. Data area. The description of the U-TOC will be omitted after sector 1. For example, when trying to record a certain piece of music on the disc 1, the system controller 11 can search for a free area on the disc from the U-TOC and record audio data there. ing. Further, at the time of reproduction, the area in which the music to be reproduced is recorded is discriminated from the U-TOC, and that area is accessed to perform the reproduction operation.

As in the P-TOC, the U-TOC sector (sector 0) shown in FIG. 3 is provided with a header first, and then, at a predetermined address position, a manufacturer code, a model code, and a song number of the first music piece. (First TNO), song number (Last TNO) of the last song, sector usage, disc serial number, disc ID, and other data are recorded. Various table pointers (P-DFA, P-EMPTY, P-
An area for recording FRA, P-TNO1 to P-TNO255) is prepared.

Then, the table pointer (P-DFA to P-TNO25
As the management table section that will correspond to (5) (01h)
Up to (FFh) 255 parts tables are provided. Each of the parts tables has the PT shown in FIG.
Similar to OC sector 0, a start address as a starting point, an end address as an ending point, and mode information (track mode) of the part are recorded for a certain part. Further, in the case of this U-TOC sector 0, the parts shown in each parts table may be connected to other parts in succession, so the start and end addresses of the connected parts are recorded in the parts table. The link information indicating is recorded.

In this type of recording / reproducing apparatus, as described above with reference to FIG. 19, the data of one music piece is physically discontinuous, that is, even if a plurality of parts are recorded, they are reproduced while accessing between the parts. By doing so, there is no hindrance to the playback operation. Therefore, a music piece or the like to be recorded by the user may be recorded in a plurality of parts for the purpose of efficiently using the recordable area. Therefore, link information is provided, for example, numbers (01h) to (FFh) given to each parts table (actually indicated by a numerical value which is a byte position in the U-TOC sector 0 by a predetermined calculation process). The parts tables can be connected by specifying the parts table to be connected. Incidentally, since the music recorded in advance in the pit form is not usually divided into parts, all the link information in the P-TOC sector 0 is "(00h)" as shown in FIG.

That is, in the management table section in the U-TOC sector 0, one part table represents one part, and, for example, a music piece formed by connecting three parts is linked by link information. The position of the parts is managed by the three parts tables.

Each of the parts tables (01h) to (FFh) in the management table section of the U-TOC sector 0 has a table pointer (P-DF) in the corresponding table instruction data section.
A, P-EMPTY, P-FRA, P-TNO1 to P-TNO255)
The contents of the part are shown as follows.

The table pointer P-DFA is shown attached to the defective area on the magneto-optical disk 1, and is one part table or a plurality of parts tables in which a track portion (= part) which becomes a defective area due to a scratch or the like is shown. The top parts table in is specified. In other words, if there is a defective part, (01h) ~
Either (FFh) is recorded, and the defective parts are indicated by the start and end addresses in the corresponding parts table. If another defective part exists, another part table is designated as the link information in the part table, and the defective part is also shown in the part table. If there is no other defective part, the link information is, for example, "(0
0h) ”and no link after that.

The table pointer P-EMPTY indicates the top part table of one or a plurality of unused part tables in the management table section. If there is an unused part table, the table pointer P-EMPTY is used as the table pointer P-EMPTY. , (01h) to (FFh) is recorded.
If there are multiple unused part tables, the part tables specified by the table pointer P-EMPTY are used to sequentially specify the part tables by link information, and all the unused part tables are linked on the management table section. To be done.

The table pointer P-FRA indicates the writable free area (including the erased area) on the magneto-optical disk 1, and 1 or the track portion (= part) which is the free area is indicated. The first part table in multiple part tables is specified. That is,
Table pointer P-FRA when free area exists
In (01h) ~ (FFh) is recorded,
In the corresponding parts table, parts that are free areas are indicated by start and end addresses. Also, if there are multiple such parts, that is, if there are multiple parts tables, the link information
Part tables with link information of "(00h)" are specified in sequence.

FIG. 4 schematically shows the management state of the parts which are the free area by using the parts table. This is when the parts (03h) (18h) (1Fh) (2Bh) (E3h) are set as the free area, this state continues to the corresponding table instruction data P-FRA and the parts table (03h) (18h) (1Fh). It shows the state represented by the link (2Bh) (E3h). The defective area and the unused parts table management mode described above are the same.

By the way, in the case of a magneto-optical disk in which no audio data such as music is recorded and there is no defect,
Parts table (01h) by table pointer P-FRA
Is designated, which indicates that the entire recordable user area of the disc is an unrecorded area (free area). And it remains in this case (02h) ~ (FFh)
Since the parts table of will not be used,
The part table (02h) is specified by the above-mentioned table pointer P-EMPTY, the part table (03h) is specified as the link information of the part table (02h), and the part table is specified as the link information of the part table (03h).
(04h) is specified, and so on.Parts table (FFh)
Are linked up to. In this case, the link information of the parts table (FFh) is set to "(00h)" indicating that there is no connection thereafter. At this time, in the parts table (01h), the start address of the recordable user area is recorded as the start address, and the address immediately before the lead-out start address is recorded as the end address.

Table pointers P-TNO1 to P-TNO255 indicate music pieces recorded by the user on the magneto-optical disk 1. For example, in the table pointer P-TNO1, one or a plurality of pieces of data in which the first music piece is recorded are recorded. The parts table that indicates the temporally first part of the parts is specified.

For example, when the first music piece is recorded on the disc without dividing tracks (that is, in one part), the recording area of the first music piece is the part indicated by the table pointer P-TNO1. It is recorded as the start and end addresses in the table.

Further, for example, when the second music piece is discretely recorded in a plurality of parts on the disc,
Each part is designated in chronological order to indicate the recording position of the music. That is, the table pointer P-TNO2
From the parts table specified in, the other parts tables are sequentially specified by the link information according to the temporal order, and the parts table in which the link information is "(00h)" is linked (as in FIG. 4, above). Form). In this way, for example, all the parts in which the data constituting the second song is recorded are sequentially designated and recorded, so that the data of the U-TOC sector 0 is used to reproduce the second song or the second song. When overwriting the area (1), the optical head 3 and the magnetic head 6 can be accessed to take out continuous music information from discrete parts, and recording can be performed efficiently using the recording area.

As described above, the area management on the disk is P
-Music recorded by the TOC and recorded in the recordable user area, free areas, etc.
Performed by OC. These TOC information are read into the buffer RAM 13 so that the system controller 11 can refer to them.

<4. Area Structure of Disc> Here, the area structure of the disc will be described. FIG. 5 schematically shows the area structure of the disk in the radial direction. In the case of a magneto-optical disk, an area in which data is recorded by embossed pits (pre-mastered area) and a groove area provided as a so-called magneto-optical area are roughly divided into pit areas shown in FIG. It is divided into

Here, as the pit area, the above-mentioned P-
The TOC is repeatedly recorded. As described above, in this P-TOC, the U-TOC position is indicated as the U-TOC start address UST _A , the lead-out start address LO _A , and the recordable user area start address. Each address position shown in FIG. 5 is shown such as RST _A and power cal area start address PC _A.

A groove area is formed following the innermost pit area of this disc. The area up to the address indicated as the lead-out start address LO _A in the P-TOC is formed in this groove area. It is a recordable area that can be recorded, and is a lead-out area thereafter.

Of the recordable areas, the recordable user area in which data is actually recorded is the recordable user area start address RS.
From T _A to the position immediately before the lead-out start address LO _A.

The area before the recordable user area start address RST _A in the groove area is used as a management area for recording / reproducing operation, the above-mentioned U-TOC and the like are recorded, and the power cal area starts. One cluster from the position indicated as the address PC _A is provided as a laser power calibration area.

The U-TOC is the U-TOC start address UST in the management area for this recording / reproducing operation.
Three clusters (1 cluster = 36 sectors) are continuously recorded from the position indicated by _A.

Then, the actual voice data is recorded in the recordable user area as shown in FIG. 5, for example. For example, in this case, the music M ₁ ~M ₄ four tracks, the address A ₀ to A ₁ part music M ₁ of the first piece of music is recorded, also music M ₂ of the second track address A ₂ to A ₃ It is recorded in the parts. Further, the third piece of music M ₃ is recorded in the parts of addresses A _{4 to} A ₅ , and the fourth piece of music M ₄ is recorded in the parts of addresses A _{6 to} A ₇ . In this state, the free area that has not yet been recorded piece of music becomes a part of the address A ₈ ~A _9. For example, such a recording state is managed in the U-TOC by the table pointers P-TNO1 to P-TNO4, P-FRA and the parts table connected thereto as described above.

<5. Access operation during playback> a. Outline Next, an outline of an access operation at the time of reproduction of the recording / reproducing apparatus of the present embodiment will be described with reference to FIGS. 6 and 7. FIG. 6 shows an example of the content of audio data recorded in the recordable user area of the disc (see FIG. 5). And in this case, as can be seen from the figure, M
_1, music three songs of M _2, M ₃ are assumed to be recorded, further, the first track M ₁ is the time part M ₁ sequentially recorded in the address A ₆ to A _{7 (1),} the address A ₀ to a ₁ part M _{1 (2),} and the address a ₁₂ to a ₁₃ parts M _{1 (3)} of the are discretely recorded. The two music M ₂ is also an address A ₄ to A ₅ parts M _{2 (1),} the address A ₂ to A ₃ parts M _{2 (2),} and the address A ₁₀ parts to A ₁₁ M
It is recorded discretely in _{2 (3)} . The third piece of music M ₃ is continuously recorded in the parts of addresses A _{14 to} A ₁₅ . Further, each part of the address A ₈ to A _9, and the address A ₁₆ to A ₁₇ is a free area.

If the disc having the recorded contents shown in FIG. 6 is reproduced from the beginning, the optical head 3 starts reading data from the part M _{1 (1)} of the first music M _1. Part M while performing the post-access operation
Read the data of _{1 (2)} → M _{1 (3)} . Next, the operation is such that the part M _{2 (1) of the} second song → the part M _{2 (2)} → the part M _{2 (3)} is read out, and the part M _{3 of the} third song is accessed to read the data.

In the present embodiment, when the amount of data currently stored in the buffer RAM 13 is equal to or larger than a predetermined amount at the stage when there is a request for access to the next part during the read operation as described above. In order to avoid the gear noise of the sled mechanism caused by the high speed driving of the sled motor, the access speed is controlled to be slow. On the other hand, if the amount of data is less than a predetermined value, the thread mechanism 5
The transfer speed is set to a high speed for quick access so that the data of the next part is read out as soon as possible to ensure the data accumulation in the buffer RAM 13 and prevent the reproduction signal from being interrupted.

For example, as specifically shown by the optical head 3 shown in FIG.
_{2 (2)} data reading is completed, and the next part, M
It is assumed that there is a request for access to _{2 (3)} . The data storage state of the buffer RAM 13 at this point is schematically shown in FIGS. In this figure, the memory area is shown by five columns, and writing is shown as data being transferred from the right side of the uppermost column, serial data is sent in as shown by the arrow in the figure, and read from the left side of the lowermost column. There is. Also, this buffer RAM 13
If the data corresponding to three columns or more is stored, the data amount is set to the predetermined value Th or more, and if the data for less than three columns is stored, the data amount is set to the predetermined value Th or less.

For example, in FIG. 7 (a), data from the first part M _{1 (1)} of the first music piece to the part M _{2 (2)} which is considered to be read out is accumulated, and is currently stored. Shows the state in which the data of the content of the part M _{1 ( 1)} is being read. In this case, as shown in the figure, the data amount of the buffer RAM 13 is stored at a predetermined value Th (shown by the broken line) or more. Is in a state. In such a case, in the present embodiment, in the case where the next part (in this case, M _{2 (3)} ) is accessed and the reproduction data is not read from the disc, the buffer RA
It is assumed that the M13 has a sufficient data storage amount such that the reproduction signal is not interrupted by the read data, and the control is performed so that the M13 is accessed at a low speed.

On the other hand, in the case of FIG. 7B, the buffer R
In the AM 13, the data up to the part M _{2 (2)} for which the reading of the disk data has been completed is accumulated, but here, the data of the content of the first part M _{1 (1)} of the first music has already been read. Since the data of the content of the next part M _{1 (2)} is currently being read out, the data storage amount of the buffer RAM 13 is the predetermined value T as shown in the figure.
It is less than h. In such a case, in this embodiment, the amount of data stored in the buffer RAM 13 is insufficient,
The amount of data in the buffer RAM 13 is empty during access (EM
It is considered that there is a possibility that the reproduction signal may be interrupted due to PTY), and for example, the thread motor is rotated at a high speed so that the next part can be quickly accessed.

That is, in the present embodiment, the access operation during reproduction is performed at a low moving speed of the optical head by the sled mechanism, except for a state where the data storage amount of the buffer RAM 13 has no margin. Is.
This reduces the chances of driving the sled mechanism at high speed, and thus reduces gear noise. For example, when the device of this embodiment is of a stationary type in which it is difficult to assume that a particularly large disturbance will be applied to the device, it is possible to always obtain a state in which data is relatively stably accumulated in the buffer RAM 13. Therefore, it is possible and effective to move the thread mechanism at a low speed during most accesses.

B. First Embodiment Next, as a first embodiment, a specific example for realizing the above-described access operation during reproduction will be described with reference to FIGS.
And FIG. 10 will be described. In the first embodiment, in order to change the access speed as described above, for example, the sled drive voltage SD applied to the sled motor of the sled mechanism 5 from the servo circuit 9 is changed. As a result, the rotation speed of the sled motor changes, and the speed at which the optical head 3 is transported by the sled mechanism 5 is switched.

FIG. 8A shows a waveform diagram of the thread drive voltage in the case where the access is performed corresponding to the case where the data storage amount of the buffer RAM 13 is the predetermined value Th or less as shown in FIG. 7B, for example. ing. Here, as shown in the figure, the sled drive voltage at the level indicated by V ₁ is applied to the sled motor for a period corresponding to the access movement amount, and high speed rotation is performed. As a result, the sled mechanism 5 makes access while moving the optical head 3 at high speed.

On the other hand, as shown in the state of FIG. 7A, in the case where the data of the predetermined value Th or less is accumulated in the buffer RAM 13, the figure is shown until the next part is accessed. As shown in the waveform diagram of FIG. 8B, the voltage V lower than the voltage level V ₁ of FIG.
_The sled motor is driven by the sled drive voltage SD of ₂ . As a result, the sled motor rotates at a lower speed than in the case of FIG. 8A, so that the sled mechanism 5 transfers the optical head 3 at a low speed for access. Alternatively, as shown in the waveform diagram of FIG. 8C, a sled drive that outputs intermittently during a period in which the voltage level remains V ₁ and the area is the same as that of the waveform of FIG. 8A, for example. Even with the voltage, the sled movement can be slowed.

Further, when the sled drive voltage is based on the PWM waveform, for example, the waveform of the pulse duty shown in FIG. 9A corresponds to the state where the data below the predetermined value Th is accumulated in the buffer RAM 13. Then, if the thread motor is rotated at high speed, the buffer RA
When the data storage amount of M13 is equal to or larger than the predetermined value Th, as shown in FIG. 9B, a PWM waveform having a smaller pulse width than the waveform of FIG. 9A is formed and applied as the sled drive voltage. This slows the sled movement.

FIG. 10 shows the processing operation of the system controller 11 for executing the switching of the sled drive voltage. In this routine, first step F1
In 01, it is determined whether or not there is a request for access to the next part, and if there is no request here, the process returns to the original routine. On the other hand, for example, in addition to the completion of reading the current part,
If it is determined that there is a request for access to the next part by performing operations such as fast-forward / fast-reverse and song search, the process proceeds to step F102 and the current buffer RA is reached.
Whether or not the data amount of M13 is accumulated at a predetermined value or more is determined based on the information from the memory controller 12, for example. Here, when the data storage amount is equal to or larger than the predetermined value, the process proceeds to step F103, and the process is executed so that the thread is moved at a low speed. That is, with respect to the sled motor, FIG.
In the case of (c) or the PWM waveform, the servo circuit 9 is controlled so that the sled drive voltage as shown in FIG. 9B is applied, and the original routine is returned to. On the other hand, if it is determined in step F102 that the data storage amount is less than or equal to the predetermined value,
In step F104, the thread drive voltage as shown in FIG. 8A or FIG. 9A is output from the servo circuit 9 to return to the original routine so that the thread can be moved at high speed. Become.

B. Second Example Next, a second example will be described with reference to FIGS. 11 to 13. In the second embodiment, when changing the access speed during reproduction, in the case of high speed, as in the first embodiment, the sled mechanism 5 moves the optical head 3 itself at high speed. By "Move", the next part is accessed. On the other hand, in the case of low-speed access, the objective lens 3a is driven mainly by driving the biaxial mechanism 4.
Access is made by a "track jump" that displaces.

FIG. 11A shows a waveform of the sled drive voltage output when the sled is moved at the time of high-speed access in the second embodiment, and such a voltage of a predetermined level is used for the access movement. By being applied to the sled motor for a period corresponding to the amount, the optical head 3 is moved at high speed by the sled mechanism 5 in this embodiment. FIG. 11B shows a tracking error signal, and during the period when the sled drive voltage is applied and the sled is moving, the traverse signal is obtained by the light spot crossing the track as shown in the figure.

FIG. 12 is a waveform diagram showing a tracking drive signal for performing track jump control during low speed access. For example, if the access operation by the track jump is started at time T _{1 in} this figure,
From this point in time, the tracking servo system and the sled servo system are made into an open loop, and as shown in FIG. 12A, an acceleration pulse is applied as a tracking drive signal TD to the biaxial drive unit that drives the biaxial mechanism 4. 12
In the tracking error signal of (b), a traverse signal is obtained because the light spot crosses the track during the jump.

It is possible to detect how many tracks are currently jumped during the track jump by counting the traverse signal. For example, at the time point when half the jump to the target track is completed (T ₂ ), the deceleration pulse is sent to the biaxial drive section. Is applied. This is to apply a voltage in the opposite direction to brake the objective lens 3a in order to close the tracking servo loop when the moving speed of the objective lens of the optical head becomes zero. And
When the speed of the objective lens 3a becomes near zero (T ₃ ).
Ends the track jump operation, closes the tracking servo loop, and closes the thread servo loop. Although a waveform diagram is not shown here, depending on the displacement state of the objective lens 3a, a sled drive voltage is applied to the sled motor to move the sled mechanism 5 to follow the track jump operation. Is.

Then, the track jump operation such as the above T _{1 to} T ₃ period is thereafter executed as shown in the T _{4 to} T ₅ period and the T _{6 to} T ₇ period until the access to the next part is completed. By doing so, in this case, the objective lens 3a is made to reach the track of the address to be accessed next, and thus the low speed access is executed.

Next, the processing operation of the system controller 11 for switching between the high speed access and the low speed access in the second embodiment is shown in the flowchart of FIG. In this routine, first, in step F201, it is determined whether or not there is a request for access to the next part. If there is no request here, the process returns to the original routine. On the other hand, if it is determined that there is a request for access to the next part, the process proceeds to step F202, and it is determined whether or not the current amount of data in the buffer RAM 13 is accumulated over a predetermined value. If the data storage amount is equal to or larger than the predetermined value, the process proceeds to step F203 to control the servo circuit 9 so that the access by the track jump operation described with reference to FIG. Return to. If it is determined in step F202 that the data storage amount is less than or equal to the predetermined value,
By proceeding to step F204 and performing the thread movement described with reference to FIG. 11, control is performed so that high-speed access is executed, and the process returns to the original routine.

C. Third Embodiment Next, a third embodiment will be described. In each of the above embodiments, the high speed / low speed access is switched based on the information of the data storage amount of the buffer RAM 13 at the time of reproduction, but in this embodiment, it is necessary to access the actual next part. The high speed / low speed access is determined based on the time information. Therefore, the access operation in the third embodiment will be described with reference to the flowchart showing the processing operation of the system controller 11 in FIG.

In this routine, first, in step F301, it is determined whether or not there is an access request to the next part. If there is no request here, the routine returns to the original routine, but there is an access request to the next part. If it is determined that it has been determined, the process proceeds to step F302 to calculate the distance to the part to be accessed next. This can be obtained by subtracting the end address of the current part from the start address of the part to be accessed next. For example, in the case of FIG. 6, the part M to be accessed next
The start address of _{2 (3)} is A ₁₀ , and the current part M
Since the end address of the _{2 (2)} A _3, (A ₁₀ -
It is sufficient to calculate A ₃ ). Then, the system controller 11 proceeds to step F303 to perform calculation for obtaining the required time T _A required to actually access the next part from the calculation result in step F302. Specifically, for example, the time A required to access from the innermost circumference to the outermost circumference of the disk is obtained in advance, and the total number of addresses from the innermost circumference to the outermost circumference of the disk is set to B, and calculated in step F302. If the distance between the created parts is C, the required time T _A required for access can be calculated as T _A = A × C / B. For example, in the case of FIG. 6, the difference between the start address A ₁₀ parts M _{2 (2)} the end address A ₃ part M _{2 (3)} from (A ₁₀ -A ₃₎
Based on the above, the required time T _A for actually accessing the part M _{2 (3)} from the part M _{2 (2)} is obtained.

When the required access time T _A is calculated in step F303, it is determined whether or not T _A <T _B for the required access time T _A and a predetermined fixed value T _B. . It should be noted that the comparison value T _B becomes empty (0) when data is no longer written to the buffer RAM 13 with respect to the average data storage amount of the buffer RAM 13 during reproduction, for example. It should be set based on the time required for. When it is determined in this step that T _A <T _B , the access required time T _A calculated in step F303 is the buffer RA during the access.
It is considered that the amount of data in M13 is obviously shorter than the time length expected to be empty, and control is performed so that the thread is moved at a low speed (F305). On the other hand, T
_If it is determined that _A <T _B is not satisfied, the required time T _A is considerably long, and the buffer RAM is
It is considered that the data amount of 13 may be insufficient, and the thread is moved at high speed (F306). The processing in steps F305 and F306 may be the same as the control described in steps F103 and F104 in FIG. Also, here, the variable access speed is controlled by switching the speed of sled movement.
Processing operations in the second embodiment (steps in FIG. 13)
(F203, F204), it may be configured to be performed by low-speed access by track jump and high-speed access by thread movement.

D. Fourth Embodiment Next, a fourth embodiment will be described. In this embodiment, high speed / low speed access is performed based on the information of the time required for accessing the next part T _A calculated in the third embodiment and the information obtained by time-converting the data storage amount of the buffer RAM 13. You will be asked to make a decision. The access operation in the fourth embodiment will be described with reference to the flowchart showing the processing operation of the system controller 11 in FIG.

In this routine, steps F401 to F4
The processing up to 03 is shown in FIG.
Since the processing is the same as the processing of steps F301 to F303, description thereof will be omitted. Then, in the next step F404, the current data storage amount of the buffer RAM 13 is obtained, and until the data storage amount becomes empty (EMPTY) under the condition that the writing is stopped in this current data storage amount. The continuation T _{C at} which the read operation is possible is calculated. This can be calculated based on the current data storage amount and the number of read bits in a predetermined unit time, for example. Next, the system controller 11 proceeds to step F405, and the required access time T _A calculated in step F403 and the above time T _C.
For and, it is determined whether or not T _C >> T _A. That is, during reproduction, writing of data to the buffer RAM 13 is stopped and only reading is performed while the next part is accessed, but even during this access period, the amount of data accumulated in the buffer RAM 13 is obviously A judgment is made as to whether or not there is sufficient time to allow the voice output to be uninterrupted. Where T _C >> T
If it is determined to be _A, it is determined that the current data storage amount has a sufficient margin, the process proceeds to step F406, and control is performed so that the thread is moved at a low speed, and T _C >> T
If it is determined that it is not _A, it is determined that there is no margin in the current data storage amount, the process proceeds to step F407, and control is performed so that the thread is moved at high speed. Actually, the access distance (time required) at each access operation
And the amount of accumulated data is different, the current data is accumulated by obtaining and comparing both data without using a fixed value each time there is an access request as in the fourth embodiment. The sled movement can be determined to be switched between high speed and low speed more appropriately depending on the state. In this embodiment as well, the access speed may be variable by switching the operation between track jump and sled movement.

<6. Access operation during recording> a. Although the access operation during reproduction of the recording / reproducing apparatus of the embodiment has been described so far, access is performed according to the data accumulation state of the buffer RAM 13 and the access time required when an access request is made even during recording. It is configured to switch between high speed and low speed. When the access is performed during recording, for example, the writing to the currently recordable free area part is completed, and the head portion (the magnetic head 6a and the optical head 3) is attached to the free area part where the data is to be written next. It may be moved. For example, in the case of FIG. 6, the writing to the free areas of the addresses A _{16 to} A ₁₇ is now completed, and the address A to be written next is
_This corresponds to the operation of accessing the free area consisting of _{8 to} A ₉ . Also, during playback, the buffer R
The access speed was switched in consideration of preventing the accumulation state of the data in the AM 13 from becoming empty during the access period. However, at the time of recording, in order to prevent the read data from overflowing during the access period, The access speed is changed based on whether or not there is enough free space in the memory.

B. Fifth Embodiment Therefore, first, a case in which the access speed is switched based on the amount of data stored in the buffer RAM 13 during recording will be described as a fifth embodiment with reference to the flowchart of FIG. The processing operation of the fifth embodiment is
This corresponds to the first embodiment at the time of reproduction shown in FIG. In this routine, first, in step F501, it is determined whether or not there is a request for access to the next part. If there is no request here, the process returns to the original routine. On the other hand, for example, if it is determined that there is a request for access to the next part in the free area, the process proceeds to step F502 to determine whether the current data storage amount in the buffer RAM 13 is less than or equal to a predetermined value set corresponding to the recording. Make a decision about whether. If it is determined that the data storage amount is less than or equal to the predetermined value, it is considered that the buffer RAM 13 has sufficient free space so as not to overflow during the access period, the process proceeds to step F503, and the thread is moved at a low speed. Control to return to the original routine. If it is determined that it is not less than the predetermined value, it is determined that the free area of the buffer RAM 13 is insufficient, and the process proceeds to step F504, where the thread is moved at a high speed, so that the parts in the next free area can be rapidly written. After it is started, it returns to the original routine.

Although the variable access speed is controlled here by changing the speed of thread movement, the processing operation of the second embodiment at the time of reproduction shown in FIG. 13 (steps F203 and F204). ), If the amount of data storage is less than or equal to a predetermined value, the processing operation is to perform low-speed access by a track jump in step F503. It may be configured to be executed.

C. Sixth Embodiment Next, a sixth embodiment will be described with reference to the flowchart in FIG. The processing operation of the sixth embodiment corresponds to the processing operation of the third embodiment during reproduction shown in FIG. In this routine, step F6
The processing operations of 01 to F603 are steps F301 to F3 in FIG.
Since the processing is the same as that of 03, the description is omitted. However, in this case, since recording is performed, in the case of FIG. 6, for example, from the end address A _{17 of the} current free area part to the start address A ₈ of the next free area part to be accessed. Time required to access T
_A is calculated.

[0102] When the access required time T _A is calculated in step F603, this access required time T _A and T _B is a predetermined fixed value _(R), is T _A <T B _(R) Determine whether or not. The comparison value T _{B (R)} here is, for example, the buffer R at the time of recording.
In the average data storage amount of AM13, the buffer R
If only the recording data is written to the AM 13, it is set based on the time required for the data amount to become full (FULL) and overflow.

In this step, if it is determined that T _A <T _{B (R)} , the access required time T _A calculated in the above step F603 is obviously the buffer R during the access.
It is considered that there is enough free space to the extent that the data amount of the AM 13 does not overflow, and control is performed so that the thread is moved at a low speed (F605). On the other hand, T _A <T
_If it is determined that it is not _{B (R),} it is considered that the required time T _A is long enough that the free space of the buffer RAM 13 may become insufficient during the access period, and the thread is moved at high speed ( F606). Even in this case, the access speed may be variable by switching the operation between track jump and sled movement.

C. Seventh Example Next, a seventh example will be described with reference to the flowchart in FIG. The processing operation of the seventh embodiment corresponds to the processing operation of the fourth embodiment at the time of reproduction shown in FIG. In this routine, step F7
The processing from 01 to F703 is the same as the processing from step F601 to F603 shown in FIG. 17 described above as the sixth embodiment, and the description thereof will be omitted. In the next step F704, regarding the current data storage amount in the buffer RAM 13, if only the write data is written, the buffer RAM 13
The time T _{C (R)} until 13 overflows is calculated, and the flow advances to step F705 to determine whether the access required time T _A and the time T _{C (R)} are T _{C (R)} >> T _A. Determine whether In other words, it is determined whether or not the current data free space has a sufficient margin so that the buffer RAM 13 is obviously not overflowed within the time required to access the next part. .

If it is determined that T _{C (R)} >> T _A, it is determined that the current data free space is sufficiently large, and the flow advances to step F706 to move the thread at a low speed. If it is determined that T _{C (R)} >> T _A is not satisfied, it is determined that there is not enough free space in the current data, and the process proceeds to step F707 to perform high-speed thread movement. I do. Also in this case, the processing operations of steps F706 and F707 may be configured such that the low-speed access by the track jump and the access processing by the high-speed thread movement are respectively performed.

Although the recording / reproducing apparatus corresponding to the magneto-optical disk has been described as the embodiment of the present invention, it is naturally applicable to the reproducing apparatus or recording apparatus corresponding to other disc-shaped recording medium. is there. For example, in a reproducing device such as a CD player, if the present invention is applied to a so-called shuffle reproduction mode in which the track reproduction order is random, the access speed is changed at the time of an access operation between songs, which occurs at this time. Gear noise can be reduced. Further, although cases have been described with the above embodiments where the access speed can be switched between two stages, the access required time information, the data storage amount information of the buffer memory, the time information obtained from the data storage amount, and the like described above. It is also possible to perform the speed switching in multiple stages in accordance with the judgment result based on the above. Further, the access speed can be continuously varied corresponding to these information. Conceivable. Also, instead of the sled mechanism, there is also one that displaces the relative position between the optical head and the disc by sliding a turntable on which the disc is mounted. In this case, the access speed by the sliding mechanism is changed. The present invention may be applied.

[0106]

As described above, according to the present invention, it is considered that the data storage amount of the buffer RAM has a sufficient margin at the time of access at the time of access, and the data free space has a sufficient margin at the time of recording. As long as it is configured to access at low speed, it is possible to reduce the generation of unpleasant gear noise that occurs when the sled mechanism is driven at high speed. As a result, there is an effect that gear noise does not hinder the listening of music or the like when the disc is reproduced or the source is monitored during recording.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram of a P-TOC sector on a disc.

FIG. 3 is an explanatory diagram of a U-TOC sector on the disc.

FIG. 4 is an explanatory diagram of a link structure of U-TOC sectors in the disc.

FIG. 5 is an explanatory diagram of an area structure of a disc.

FIG. 6 is an explanatory diagram showing a recording state of the disc in the example.

FIG. 7 is an explanatory diagram conceptually showing the data accumulation state of the buffer RAM during reproduction in the embodiment.

FIG. 8 is a waveform diagram showing a sled drive voltage according to the first embodiment.

FIG. 9 is a waveform diagram showing a sled drive voltage according to the first embodiment.

FIG. 10 is a flowchart of processing of an access operation according to the first embodiment.

FIG. 11 is a waveform diagram showing a sled drive voltage according to the second embodiment.

FIG. 12 is a waveform diagram showing a track jump operation of the second embodiment.

FIG. 13 is a flowchart of processing of an access operation according to the second embodiment.

FIG. 14 is a flowchart of a process of an access operation according to the third embodiment.

FIG. 15 is a flowchart of a process of an access operation according to the fourth embodiment.

FIG. 16 is a flowchart of a process of an access operation according to the fifth embodiment (during recording).

FIG. 17 is a flowchart of processing of an access operation according to the sixth embodiment (during recording).

FIG. 18 is a flowchart of a process of an access operation according to a seventh embodiment (during recording).

FIG. 19 is an explanatory diagram of a recording form of a disc.

[Explanation of symbols]

 1 Disk 3 Optical Head 3a Objective Lens 5 Thread Mechanism 6a Magnetic Head 8 Encoder / Decoder Section 9 Servo Circuit 11 System Controller 12 Memory Controller 13 Buffer RAM 14 Encoder / Decoder Section 15 D / A Converter 18 A / D Converter

Claims (12)

[Claims] 1. A disk-shaped recording medium in a reproducing apparatus, comprising: a reading unit that reads data from a disk-shaped recording medium; and a storage unit that temporarily stores the data read by the reading unit and outputs the data as reproduction data. As a method of transferring the access mechanism to access the reading means to the required access destination position, the amount of data accumulated in the storage means and / or the time required for the reading means to move to the access destination position Based on the above, the transfer method of the access mechanism is characterized in that the transfer speed at the time of access is made variable. 2. A reading means for reading data from a disc-shaped recording medium, a storage means for temporarily storing the data read by the reading means and outputting it as reproduced data, and a required access target position of the disc-shaped recording medium. In the reproducing apparatus including an access unit that accesses the reading unit, a control unit that changes the transfer speed of the access unit based on the determination result of the data storage amount of the storage unit is provided. Playback device. 3. A reading means for reading data from a disc-shaped recording medium, a storage means for temporarily storing the data read by the reading means and outputting it as reproduced data, and a required access target position of the disc-shaped recording medium. A reproducing device having access means for accessing the reading means, the transfer speed of the access means based on the result of calculating the time required for the reading means to move to the access target position. A reproducing apparatus, characterized in that a control means for changing the is provided. 4. A reading means for reading data from a disc-shaped recording medium, a storage means for temporarily storing the data read by the reading means and outputting it as reproduced data, and a required access target position of the disc-shaped recording medium. In a reproducing apparatus including an access unit that accesses the reading unit, a determination result of a data storage amount of the storage unit and a time required for the reading unit to move to an access target position are calculated. A reproducing apparatus comprising control means for varying the transfer speed of the access means based on the result. 5. The first access means for displacing the relative position between the objective lens of the reading means and the disk-shaped recording medium; and the objective lens and the disk-shaped recording larger than the first access means. A second access unit capable of displacing the relative position with respect to the medium is provided, and the control unit changes the transfer speed at the time of access by switching between the first access unit and the second access unit. The reproducing apparatus according to claim 2, 3 or 4, wherein the reproducing apparatus is configured to: 6. The access means comprises first access means for displacing the relative position between the objective lens of the reading means and the disk-shaped recording medium, and the objective lens and disk-shaped recording larger than the first access means. A second access unit capable of displacing a relative position with respect to the medium, wherein the control unit changes the drive voltage level and / or the drive time for operating the second access unit, The reproducing apparatus according to claim 2, 3 or 4, wherein the reproducing speed is variable. 7. A recording comprising a storage means for temporarily storing input data and outputting it as recording data, and a recording means capable of recording the recording data output from the storage means on a disc-shaped recording medium. As a method of transferring an access mechanism for accessing the recording unit to a desired access target position of the disk-shaped recording medium in the apparatus, the data storage amount of the storage unit and / or the recording unit is moved to the access target position. A transfer method of an access mechanism, wherein a transfer speed at the time of access is varied based on the time required for the access. 8. A storage unit for temporarily storing input data and outputting it as record data, a recording unit capable of recording the record data output from the storage unit on a disc-shaped recording medium, and the disc-shaped recording medium. In a recording apparatus including an access unit that accesses the recording unit for a desired access position of a recording medium, a transfer speed of the access unit is changed based on a determination result of a data storage amount of the storage unit. A recording apparatus provided with a control means. 9. A storage unit for temporarily storing input data and outputting it as recording data, a recording unit capable of recording the recording data output from the storage unit on a disk-shaped recording medium, and the disk-shaped recording medium. In a recording apparatus including an access unit that causes the recording unit to access a required access destination position of a recording medium, based on a result of calculating a time required for the recording unit to move to the access destination position. And a control means for varying the transfer speed of the access means. 10. Storage means for temporarily storing input data and outputting it as recording data, recording means capable of recording the recording data output from the storage means on a disc-shaped recording medium, and the disc-shaped recording medium. In a recording apparatus including an access unit that accesses the recording unit to a required access destination position of a recording medium, a determination result of a data storage amount of the storage unit and the recording unit moves to the access destination position. A recording apparatus comprising a control means for varying a transfer speed of the access means based on a result of calculating a time required for the recording. 11. The access means comprises: first access means for displacing the relative position between the objective lens of the recording means and the disk-shaped recording medium; and the objective lens and disk-shaped recording larger than the first access means. A second access unit capable of displacing the relative position with respect to the medium is provided, and the control unit changes the transfer speed at the time of access by switching between the first access unit and the second access unit. The recording device according to claim 8, 9 or 10, wherein the recording device is configured to: 12. The access means comprises first access means for displacing the relative position between the objective lens of the recording means and the disk-shaped recording medium, and the objective lens and disk-shaped recording larger than the first access means. A second access unit capable of displacing a relative position with respect to the medium, wherein the control unit changes the drive voltage level and / or the drive time for operating the second access unit, The recording apparatus according to claim 8, 9 or 10, wherein the recording speed is variable.