JP2623045B2 - Playback control circuit of disk playback device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit for reproducing information from an optical disk and, more particularly, to a circuit for promptly controlling the release from a pause state after reproduction.

[0002]

2. Description of the Related Art Nikkei Electronics December 9, 1991, pages 160 to 168, published by Nikkei McGraw-Hill Company.
The page discloses a specific configuration of a new audio recording / reproducing system called a mini-disc. This system is a system that encodes an audio signal and further compresses the data to compress the amount of recording data, and compresses the compressed data on the time axis to intermittently record the data on a small magneto-optical disk. In the case of this system, intermittent recording is performed with a recording unit of about 0.4 seconds of compressed data formed by compressing data corresponding to about 3 seconds of audio data of two channels on the left and right. It is necessary to provide a memory for storing audio data more than the recording unit (one cluster).

If the capacity of this memory is increased, re-recording is possible not only when a recording error occurs during recording, but also when a reproduction error occurs during reproduction, re-reproduction is possible. Even if the recording sound or the reproduction sound is interrupted, it can be eliminated.

[0004]

However, in the above-mentioned prior art, it is necessary to set a pause during recording or reproduction, like other recording / reproducing apparatuses. However, if the intermittent recording operation is paused simply in association with the setting of the recording pause, a disadvantage occurs that the audio information before the recording pause stored in the memory is not recorded. Therefore, it is conceivable to record only the data stored before the recording pause setting after the recording pause setting. However, since the recording is performed intermittently in recording units, it is difficult to perform data processing for the recording. Become.

When the playback pause is set, the output audio data is simply muted, and when the playback pause is released and the playback end of the recording track corresponding to the pause setting timing is searched to restart the playback, the generation of the playback audio is delayed. . Therefore, the present invention proposes a configuration in which the sound before the recording pause is set is reliably recorded, the generation of the sound is interrupted promptly with the setting of the reproduction pause, and the reproduction sound is generated without delay with the release of the reproduction pause. Is what you do.

[0006]

The present invention is characterized in that at least a read prohibition command means 82 for restricting reading from the memory in conjunction with the setting of the reproduction pause is provided.

[0007]

According to the present invention, when the reproduction pause is set, the reading of the memory is interrupted and the sound generation is immediately interrupted. At the same time as the pause release operation, the reading of the memory is started and the sound is immediately generated.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to the above-described mini disk system will be described below. FIG. 1 is a functional block diagram illustrating a schematic configuration of the present embodiment.
Input audio data sampled at the same sampling frequency as the D format is derived. The input audio data is supplied to a data compression / decompression unit 3 in a data decompression mode.
Is supplied to the data storage / reading means 4 for compression by the ATRAC method, which is about one-fifth, and is converted into compressed data for input in units of sound groups (424 bytes) and stored in the memory M. You.

The data storage and reading means 4 generates a storage address from a storage address generation circuit 40 in synchronization with the generation of the input compressed data, and causes the memory M to store the input compressed data in sound group units. The data storage and reading means 4 further includes a data amount detection circuit 41 and a read address generation circuit 42 as hardware circuits, and generates a difference between the read address and the storage address from the data amount detection circuit 41 as an accumulated data amount. At the recording timing, a read address is generated by the read address generation circuit 42 so as to read one cluster (176 sound groups = 32 sectors) of recording audio data.

The stored data amount is supplied to a microcomputer for a system controller. The microcomputer 8 for the system controller includes a recording / reproducing command means 81 constituted by software.
When the value reaches one cluster (2336 bytes) or a value close to the value, a recording command is input to the search means 6 which forms a part of the recording / reproducing means 5. The search means 6 inputs an absolute address signal called ADIP reproduced by the recording / reproducing means 5 as a tracking signal component, and causes a track jump to wait for the pickup at the absolute address of the recording start end following the previous recording end. A pulse is input to the recording / reproducing means 5 to enter a recording standby state. When a recording start is detected by the generation of a recording instruction, a recording data read instruction is supplied to the read address generating circuit 42, and the recording audio data is read from the memory M. To start.

The read recording audio data for one cluster is supplied to the recording / reproducing means 5. The recording / reproducing means 5 is encoded via a CIRC encoder and an EFM encoder and supplied to a recording magnetic head.
As a result, in the disc record, the intermittent recording track is recorded by magnetic field modulation following the previous recording track. During recording, intermittent recording is performed for each cluster by repeating the above operation.

Next, the reproducing operation of this embodiment will be described. In the case of the present embodiment, reproduction is executed in units of two sectors each composed of 11 sound groups, and storage is executed such that the memory M is always full. The recording / reproducing means 5
Supplies optical data to the recording track sequentially by a pickup, sequentially decodes the reproduced data by an EFM decoder and a CIRC decoder, and supplies reproduction audio data to the data storage / readout means 4 as an output of the recording / reproduction means 5. The storage address generating circuit 4 synchronizes with the input of the audio data for reproduction.
0 supplies a storage address to the memory M, and stores audio data for reproduction in the memory M.

The stored data is sequentially read from the memory M as output compressed audio data in accordance with the read address generated by the read address generating circuit 42 in sound group units, and is sequentially supplied to the data compression / decompression means 3.
The data amount detection circuit 41 in the data storage and reading means 4 obtains the stored data amount and supplies the value to the microcomputer 8 for the system controller. The recording / reproducing command means 81 in the microcomputer for system controller 8 supplies a reproducing command to the search means 6 when the free space of the storage data amount is two sectors or more. The search means 6 inputs a sector address given in sector units from the recording / reproducing means 5, sequentially reproduces recording tracks during a period in which a reproduction command is generated, and issues a reproduction data storage command to the storage address generation circuit. At 40, the audio data for reproduction is stored. The recording / reproducing command means 8 when the amount of stored data is almost full.
When the reproduction command is released from step 1, the search means 6 stores the sector address at the end of reproduction to put the pickup in a standby state, cancels the data storage command, and prevents generation of a storage address.

When the amount of free data becomes two or more sectors due to the reading of the output compressed data, the recording / reproducing command means 81
Generates a reproduction command, cancels the reproduction standby state of the search means 6, resumes reproduction, and stores reproduction audio data in the memory M. As a result of storing audio data for reproduction for two sectors,
When the free data amount becomes 2 sectors or less, the recording / reproducing command means 81 cancels the reproducing command. In conjunction with this release, the reproduction operation falls into a standby state, and repeats reproduction after waiting for an increase in the amount of free data.

The output compressed data sequentially read from the memory M is supplied to the data compression / decompression means 3 in the decompression mode and decompressed. The decompressed output audio data is input to the audio output means 2, converted into an analog signal, and supplied to a sound emitting device such as a speaker. The operation of the data compression / decompression means 3 among the above-mentioned means is switched according to the mode. The circuit of the EFM encoder and the decoder and the CIRC encoder and the decoder in the recording / reproduction means 5 are similarly switched by switching the operation. Shared.
Although the recording and reproduction operations described above are not entirely known, they have a normal configuration as a mini-disc system. The features of this embodiment are as follows.

In this embodiment, when the pause button of the operation input means 9 is operated during recording, a recording pause command is input to the microcomputer 8 for the system controller. The mute command means 80 constituted by software in the system microcomputer 8 generates a mute command immediately upon receiving the input of the recording pause signal.
The mute means 7 at the subsequent stage is operated for a certain period (a period corresponding to one cluster), and the input audio data is defined at the 0 level. As a result, the mute audio data is compressed and supplied to the memory M immediately after the recording pause operation. Then
When the recording pause is performed, the state of the memory M is as shown in FIG. 5 where one cluster of data is not formed and an empty area exists, but the mute audio data is stored in the empty area as shown in FIG. Thus, data of one cluster can be formed. Further, the recording re-instruction means 81 before inputting the recording pause signal limits the generation of the recording instruction after the input of the recording pause signal to one time. Then, the intermittent recording tracks for one cluster including the mute information are recorded on the disk, and the recording standby state is set. In the above-described configuration, when the recording pause state continues for a certain period or more, the power supply to the recording / reproducing means 5, the memory M, the data storage / readout means 4, and the data compression / expansion means 3 is deactivated.

When the pause is released in the recording pause state of the power supply deactivation, the power deactivation state is released, the respective units are started, and the recording operation is restarted. If the recording pause is released before the power is turned off, both address generating means 40 and 42 are reset, and storage and reading from the initial address are started. FIG. 2 shows a change in the amount of data used in the memory M before and after the recording pause described above is performed. Before the recording pause is made, the memory M
When the input compressed audio data sequentially stored in the storage unit reaches one cluster or a value close to the value as described above, the recording / reproducing means 5 as recording audio data in units of one cluster.
The operation sent to is repeated. After a pause is made at time t11, mute audio data is stored to form one cluster of data, which is recorded on the disk. After the time t12 when the recording on the disk is completed, the storage of the input compressed data in the memory M is stopped. Thereafter, after a certain period, the above-described power supply deactivation is performed. This power deactivation is effective for a portable type player driven by a battery. When the pause is released at time t13, the player is powered on again, and the memory M starts storing the input compressed data. As described above, since both address generating means 40 and 42 are reset, as can be seen from FIG. 2, the memory M can start storing the input compressed data from the state of zero memory usage.

If the power is turned off after setting the recording pause, even if the power is turned on together with the release of the pause, the response characteristics of the motor startup may be poor depending on the player, and there is a possibility that the voice recording immediately after the release of the pause may not be possible. Therefore, if the disk motor continues to be driven even during the recording pause period, the above-mentioned risk is eliminated. In the description given so far, when the recording pause is made, the memory M stores 1
If no cluster data was formed, mute audio data was stored in the empty area. However, storage of the mute audio data is not essential as described below. FIG. 6 shows the data structure of one cluster, which is a unit of recording on the disk. However, an invalid subcode frame number can be written in the control data D as shown. For example, the upper 2 bits 01 indicate that the second half of the data is invalid, 10 indicates that the first half of the data is invalid, and the lower 5 bits indicate the start or end number of the invalid subcode frame. I have. At the time of reproduction, control may be performed so as to perform reproduction in consideration of the invalid subcode frame. In this example, if the upper two bits are 00, all subcode frames are valid, and if the upper two bits are 11, all subcode frames are invalid.
In that case, the latter 5 bits may be undefined.

Next, when the pause button is operated in the playback state, a playback pause command is generated and input to the read inhibition command means 82 of the microcomputer for the system controller. The read prohibition command means 82 immediately inputs a read prohibition command to the read address generation circuit 42. As a result, the read address generation circuit 42 interrupts the subsequent data read of the sound group. As a result, the storage data amount does not decrease, the reproduction standby state of the recording / reproducing means 5 is maintained, and the storage state of the memory M is maintained as it is to form a reproduction standby state.

When the reproduction pause is released in the reproduction standby state, the read prohibition command is also released, and the reproduction sound is formed and derived immediately, and the state smoothly transitions to the normal reproduction state. FIG.
(A) and (b) show a change in the usage of the memory M when the reproduction is paused from the described reproduction. In the normal reproduction, when the empty data amount of the memory M becomes two or more sectors as described above, the operation of storing the reproduction audio data in the memory M is repeated. Time t2 in the case of FIG.
The pause in step 1 is during reading of the compressed data for output to the data compression / decompression means 3. In this case, the pause operation is performed immediately after the pause is set. During the pause, the contents stored in the memory M are maintained as they were when the pause was set. After the pause release at time t22, the data stored in the memory M is sent to the data compression / decompression means 3.

On the other hand, in FIG. 3B, the pause is set at the time point t31 when the audio data for reproduction is being stored. Playback audio data is stored in units of two sectors, but the pause is set during storage.
At time t32 when the storage of the sector data is completed, the storage state of the memory is fixed. At this time, the data amount of the memory M is almost full. Thereafter, the data stored in the memory M is maintained until the pause is released at time t33.

In the above-described embodiment, the microcomputer of the system controller is constituted by software, but it may be constituted by hardware. Further, in this embodiment, in the intermittent recording / reproducing state, the search means is always in the standby state at the start of recording / reproducing. However, it goes without saying that the search state may be set in conjunction with the recording / reproducing command.

[0023]

According to the present invention, after the pause setting operation, the reproduction data in the memory is retained without being erased, and the data is generated before the reproduction by the pickup after the pause release operation. Can be quickly resumed.

[Brief description of the drawings]

FIG. 1 is a functional block diagram showing one embodiment of the present invention.

FIG. 2 is a diagram illustrating a usage amount of a memory M when a recording pause is performed according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating a usage amount of a memory M when a reproduction pause is performed according to an embodiment of the present invention.

FIG. 4 is a diagram illustrating a state of a memory M when a recording pause is performed in one embodiment of the present invention.

FIG. 5 is a diagram illustrating a state of a memory M in which a recording pause is performed and mute information is stored in one embodiment of the present invention.

FIG. 6 is a diagram illustrating a configuration of one cluster which is a recording unit according to one embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 voice input means 2 voice output means 3 data compression / decompression means 4 data storage / readout means 5 recording / reproducing means M memory 7 mute means 80 mute command means 81 recording / reproducing means 82 read inhibit command means

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Takao Inoue 2--18 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Miyuki Okamoto 2-18 Keihanhondori, Moriguchi-shi, Osaka (56) References JP-A-5-159460 (JP, A)

Claims (1)

(57) [Claims] 1. A reproducing means (5) for reproducing a disk at high speed by a built-in pickup, a storage address generating means (40) for storing high-speed reproduced data obtained by the reproducing means in a memory (M) at a high speed; M), a read address generating means (42) for sequentially reading stored data, a data amount detecting means (41) for detecting an amount of data stored in the memory (M), and a data amount detecting means (42). Based on the output of 41), the reproducing means (5) is set in a reproduction standby state and the generation of the storage address from the storage address generating means (40) is prohibited until the data amount becomes a predetermined amount or less, and the data amount is reduced. A search means for setting the reproduction means (5) to a reproduction state and generating a storage address from a storage address generation means (40) when the predetermined amount or less is reached; In conjunction with decree was operated said search means
Leave to prohibit the generation of the read addresses from the read address generating means (42), reading prohibition command means for generating a read address from the read address generating means in conjunction with the playback pause release command (42) and (82) The playback control circuit of the disk playback device that is arranged.