JPH11232774A - Reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform a long-time operation by greatly reducing power consumption. SOLUTION: After the start of reproducing, when the accumulated data quantity D of a buffer memory 13 reaches a maximum accumulated data quantity Dmax, reproducing data are intermittently written in the buffer memory 13. Then, when the accumulated data quantity D is maintained at a specified accumulated data quantity D1 or higher for specified time Tth or more, the operation of a data reading section 20 is completely stopped temporarily. Thus, while the operation of the data reading section is unnecessary, power consumption in the data reading section is greatly reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reproducing apparatus capable of reproducing data from a recording medium.

[0002]

2. Description of the Related Art In a reproducing apparatus capable of executing a reproducing operation of various recording media such as an optical disk, data read from a recording medium by an optical head is temporarily stored in a buffer memory so that sound output is not interrupted by disturbance such as vibration. And reads out data from a buffer memory at a predetermined timing, converts the data into a reproduced sound signal, and outputs the signal.

In such a reproducing apparatus, the bit rate for supplying data read from the optical head to the buffer memory is set higher than the bit rate for reading data from the buffer memory. In other words, by increasing the rotation speed of the spindle motor for rotating the recording medium to about twice the normal speed, and writing data to the buffer memory at a higher speed than reading data from the buffer memory, Even if data is always read out from the optical head, a certain amount of data read from the optical head is stored in the buffer memory during the reproducing operation. Thus, even if the operation of reading data from the recording medium by the optical head is temporarily disabled due to, for example, a track jump due to disturbance or the like, the reproduced sound is continuously output without interruption.

The operation of the optical head and the signal system from the optical head to the buffer memory does not supply data beyond the writable remaining capacity of the buffer memory even when writing to the buffer memory at a high rate. So that it is running intermittently. While the data is not actually supplied to the buffer memory, the optical head is controlled to a so-called pause (pause) state, and repeats the one-track jump to perform scanning on the same track to perform scanning from the next track. It waits until the data supply timing.

[0005]

However, in the above-described reproducing apparatus, although it depends on the recording capacity of the buffer memory and the setting of the write / read bit rate, the optical head and the optical head are actually transferred from the optical head to the buffer memory. In the signal system, the operation of supplying data to the buffer memory is executed only for a short period of time, and the rest of the time is in a standby state. That is, there is a problem that useless power consumption is performed for a long time in the optical head and the signal system from the optical head to the buffer memory even during the period when the data supply operation to the buffer memory is not performed.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a reproducing apparatus which eliminates useless power consumption and enables long-time operation with efficient power consumption is provided. The purpose is to provide.

In order to achieve the above object, data reading means for reading data from a recording medium, storage means for holding reproduced data read by the data reading means, and control for controlling operations of the data reading means and the storage means Means, wherein the read bit rate of the reproduced data from the storage means in the unit time is set to be lower than the write bit rate of the reproduced data to the storage means in the unit time. After the storage amount of the reproduction data in the storage unit reaches a certain storage amount, when the time during which the storage amount is kept equal to or more than the first storage amount reaches a specific time, the operation of the data reading unit is stopped, When the storage amount of the reproduced data in the step (c) becomes equal to or less than the second storage amount, the operation of the data reading means is controlled to be restarted.

[0008] The apparatus further includes data reading means for reading data from the recording medium, storage means for holding the reproduced data read by the data reading means, and control means for controlling the operations of the data reading means and the storage means. In the reproducing apparatus, the read bit rate of the reproduced data from the storage means per unit time is set smaller than the write bit rate of the reproduced data to the storage means per unit time. A history information setting means for setting history information of the situation, wherein the control means sets the time during which the storage amount of the reproduction data in the storage means reaches a certain storage amount and is maintained at or above the first storage amount for a specific time. The operation of the data reading means is stopped when the data amount reaches the storage amount, and when the storage amount of the reproduction data in the storage means becomes equal to or less than the second storage amount, the storage means is operated in accordance with the history information. Set the write bit rate of the reproduced data to, and to control so as to resume the operation of the data reading means.

The control means sets the write bit rate by setting the rotation speed of the spindle motor. Still further, the history information setting means measures an accumulation time when the reproduction data is accumulated in the storage means, and uses the measured time as history information.

According to the present invention, when the operation of the data reading means is executed, reproduced data is gradually accumulated in the storage means due to the difference between the write bit rate and the read bit rate for the storage means. . Then, the amount of data stored in the storage unit reaches a certain storage amount in the storage unit, reading of the reproduction data to the storage unit is performed intermittently, and a period during which the storage amount is to be kept equal to or more than the first storage amount is specified. When the time is reached,
The operation of the data reading means is stopped. In other words, in this case, the influence of disturbance or the like is small, and the writing of the reproduction data from the data reading means to the storage means is performed stably. Therefore, the operation of the data reading means is stopped to reduce the power consumption. So that

Further, according to the present invention, when the data storage amount in the storage means becomes equal to or less than the second storage amount, according to history information which is the storage time when the reproduction data is stored in the storage means,
By controlling the rotation speed of the spindle motor, setting the write bit rate of the reproduced data to the storage means, and restarting the operation of the data reading means, the optimum value according to the data storage amount of the storage means is obtained. Write reproduction data at the write bit rate.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a compact disk player will be described as an example of a reproducing apparatus according to an embodiment of the present invention. FIG. 1 is a block diagram showing a main part of a compact disk player according to the present embodiment. As shown in FIG. 1, a reproducing apparatus according to the present embodiment includes a data reading section 20 for reading data from an optical disc (compact disc), and a data temporary storage section for temporarily storing the read data. Roughly divided into 30,
The reproduction data read from the data temporary storage unit 30 is converted into an analog signal and supplied to a reproduction signal processing unit (not shown).

The disk 1 is, for example, an optical disk on which audio data is recorded. When loaded on a disk table, the disk 1 is driven to rotate at a constant speed (CLV) by a spindle motor 2 during a reproducing operation. Then, data stored in a pit form on the disk 1 is read by the optical head 3 and supplied to the RF amplifier 6. The output of the RF amplifier 6 is supplied to a decoder 7 and a servo circuit 8.

The optical head 3 is equipped with a laser diode as a laser output unit, an optical system including a polarizing beam splitter and an objective lens, and a detector for detecting reflected light. The objective lens 3a includes a biaxial mechanism 4
The optical head 3 is movable in the radial direction of the disk by a sled mechanism 5.

The servo circuit 8 generates various servo drive signals of focus, tracking, sled, and spindle from a focus error signal and a tracking error signal from the RF amplifier 6 and a spindle error signal from the decoder 7 and executes a servo operation. Let it.

The reproduced RF signal obtained by the RF amplifier 6 is supplied to a decoder 7, which performs EFM demodulation and CI
The data temporary storage unit 30 that has been subjected to processing such as RC decoding
Sent to That is, the data is temporarily written to the buffer memory 13 by the memory controller 12.

The reproduction data written in the buffer memory 13 is read at a predetermined timing, converted into an analog signal by a D / A converter 14, supplied to a predetermined amplification circuit from a terminal 15, and reproduced and output. You. For example,
These are output as L and R audio signals.

Here, writing / reading of data to / from the buffer memory 13 is performed by the memory controller 12 by specifying an address under the control of a write pointer and a read pointer.

FIG. 2 conceptually shows the operation of writing / reading data to / from the buffer memory 13. Assume that addresses 0 to n are set as data areas in the buffer memory 13. (Actually, in addition to the audio signal data, data for controlling the reproduction operation and the like are also stored in the buffer memory 13, so that a storage area other than the audio signal data is set).

As shown in FIG. 2A, the write pointer W and the read pointer R are sequentially incremented from address 0 to address n, and the address n
After that, control is performed in a so-called ring form in which address 0 is reset again.

Then, a reproducing operation is started, and data is read from the optical disk 1 by the data reading section 20.
When the data is supplied to the data temporary storage unit 30, FIG.
, The write pointer W is sequentially incremented, and data is written to each address accordingly. In addition, in response to the read pointer R being sequentially incremented almost simultaneously (or at a point in time when data has been accumulated to some extent), data is read from each address and output to the D / A converter 14. To go.

At some point, as shown in FIG. 2C, the address indicated by the write pointer W catches up with the address indicated by the read pointer R (when the read pointer R is at the address x, the write pointer The address of W is x-1). That is, the data is stored in the buffer memory 13 in the full capacity. At this time, the increment of the write pointer W is stopped, and the operation of reading data from the optical disk 1 by the data reading unit 20 is also stopped. However,
Since the read pointer R is continuously incremented, the reproduced audio output is not interrupted.

[0023] Thereafter, only the reading operation from the buffer memory 13 will be continued, for example, the data storage remaining D _R in the buffer memory 13 at some point as shown in FIG. 2 (d) is,
It is assumed that the amount has become equal to or less than a set predetermined amount. Here, the data reading operation by the data reading unit 20 and the increment of the write pointer W are restarted, and the process is executed again until the address of the write pointer W catches up with the address of the read pointer R. As described above, the operation of writing the reproduced data to the buffer memory 13 in the data reading unit 20 is performed intermittently.

By outputting the reproduced sound signal through the buffer memory 13 in this manner, even if tracking is lost due to disturbance or the like, the output of the reproduced sound is not interrupted, and the data storage remains. For example, by accessing the correct tracking position and restarting the data reading during the operation, the operation can be continued without affecting the reproduction output. That is, the buffer memory 13 functions as a shock-proof memory that significantly improves the vibration proof function.

The system controller 9 controls the data read / write operation in the data temporary storage unit 30 via the memory controller 12 together with the read operation of the reproduced data in the data read unit 20. When the writing of data to the buffer memory 13 is temporarily stopped as described later, the laser output of the optical head 3 of the data reading unit 20 is turned off, and at the same time, the operation of each circuit unit is temporarily completely stopped. To stop. That is, for example, the power supply to each circuit unit of the data reading unit 20 is cut off or the supply of the operation clock is stopped.

The display section 10 is constituted by, for example, a liquid crystal display.
The playback progress direction, operation state, and the like are displayed based on the control of the system controller 9. The key operation unit 11 is an operation input unit provided with keys used for user operation, and includes a reproduction key, a stop key, an AMS key, a search key, and the like.

The reproducing operation realized by the reproducing apparatus according to the present embodiment having such a configuration will be described with reference to the flowchart of FIG. 3 and the diagram showing the state of the amount of data stored in the buffer memory 13 of FIG. I will explain while. For example, when the user performs a reproduction operation with the key operation unit 11,
The reproduction operation of the optical disc 1 is started. In this case, first, the operation of the data reading unit 20 must be executed for the reproducing operation, so the system controller 9 executes the reproduction start-up process for the data reading unit 20 (S
100).

In the reproduction start-up process, for example, after the laser output of the optical head 3 is turned on, the servo circuit 8
When the two-axis mechanism 4 is driven to reach the focus pull-in area, the focus servo loop is closed and the focus servo is applied.
In addition, the rotation instruction of the spindle motor 2 is instructed, and the rotation speed is controlled to a predetermined speed (for example, the normal speed is set to the double speed in the reproducing apparatus of the present embodiment). Further, the tracking servo is turned on. When the above-described reproduction start-up processing is completed, data can be read from the optical disk 1, and a reproduction signal is extracted by the optical head 3.

Next, the system controller 9 writes the reproduced data subjected to the predetermined signal processing in the data reading section 20 to the buffer memory 13, and at the same time as the writing of the reproduced data (or to a certain extent, the data is read). Control is performed so that the reproduced data is read from the buffer memory 13 (at the time when the data is accumulated) (S101). In this case, if the rotation speed of the spindle motor 2 for rotating the disk 1 is a normal speed (double speed), the write bit rate to the buffer memory 13 is higher than the read bit rate. 13 bit rate (high speed)
The excess data due to the difference between the data and the read bit rate (low speed) is stored in the buffer memory 13.

Then, in step S102, the system controller 9 checks the amount of data stored in the buffer memory 13 via the memory controller 12, and then proceeds to step S103, in which the system controller 9 performs a check on the entire reproduction data storage area of the buffer memory 13. Whether the data has been stored in the buffer memory 13,
It is determined whether the maximum accumulated data amount Dmax of the buffer memory 13 has been reached.

Here, when it is determined that the accumulated data amount D of the buffer memory 13 has not reached the maximum accumulated data amount Dmax, the process returns to step S101 and the processing from step S101 is executed. In step S103, when the accumulated data amount D of the buffer memory 13 reaches the maximum accumulated data amount Dmax, the process proceeds to step S104.

That is, the processing in step S101 is as follows:
The operation is performed from time t1 in FIG. 4 at which the writing of the reproduction data to the buffer memory 13 is started to time t2 when the amount of data stored in the buffer memory 13 reaches the maximum stored data amount Dmax.

In step S104, the system controller 9 resets / starts a timer provided therein and proceeds to step S105. Step S
In 105, the reading of the reproduction data from the buffer memory 13 is performed continuously,
3 is controlled so as to intermittently write the reproduction data to the reproduction data 3.

That is, the amount of data stored in the buffer memory 13 reaches the maximum stored data amount Dmax,
After the time t2 in FIG. 4 where the writing of the reproduction data to the buffer memory 3 is performed intermittently, the writing of the reproduction data to the buffer memory 13 is performed intermittently.

Then, in step S106, after checking the amount D of data stored in the buffer memory 13, the process proceeds to step S107, and it is determined whether the amount D of data stored in the buffer memory 13 is equal to or greater than a predetermined amount D1.

Here, if the accumulated data amount D of the buffer memory 13 is not equal to or greater than the predetermined accumulated data amount D1, step S
Returning to step 104, the processing from step S104 is executed. If the accumulated data amount D of the buffer memory 13 is equal to or larger than the predetermined accumulated data amount D1, the process proceeds to step S108, and the timer value T that has been reset and started in step S104 is replaced with the preset predetermined timer value T
Determine if it is greater than th.

In step S108, if the timer value T is smaller than the specific timer value Tth, the process returns to step S105, and executes the processing from step S105. Such a processing operation is performed by setting the timer value T in step S108.
Is performed until it is determined that the timer value has become equal to or more than the specific timer value Tth. When the timer value T becomes equal to or more than the specific timer value Tth, the process proceeds to step S109.

In the processing in steps S107 and S108, it is determined whether or not the reproduction data has been stably written into the buffer memory 13. That is, when the reproduction data is normally written to the buffer memory 13, the write bit rate of the buffer memory 13 is higher than the read bit rate.
Is almost constant or slightly reduced.

Accordingly, the specific time Tth from the time t2 in FIG.
In the period up to the time point t3, when it is assumed that the reproduction data is stably written to the buffer memory 13 with little disturbance or the like, the data amount that should be actually stored in the buffer memory 13 is stored data. It is set in advance as the amount D1. Thus, when the accumulated data amount D actually accumulated in the buffer memory 13 has changed to be equal to or greater than the accumulated data amount D1 during the period of the time t3 after the elapse of the specific time Tth from the time t2 in FIG. 13, it can be determined that the writing of the reproduction data to the memory 13 has been performed stably.

The accumulated data amount D1 is arbitrarily set according to the time required (the ability of the servo circuit 8 and the like) from when the system controller 9 stops writing the reproduced data to when the rewriting is executed. For example, if the time required from the stop of the writing of the reproduction data to the execution of the rewriting is short, the accumulated data amount D1 ≒ the maximum accumulated data amount Dmax.

Therefore, in step S108, when the timer value T has become equal to or greater than the predetermined timer value Tth, the process proceeds to step S109, in which the system controller 9 temporarily stops writing the reproduction data to the buffer memory 13. To At this time, the system controller 9 controls the laser output of the optical head 3 of the data reading unit 20 to be turned off, for example, and at the same time, temporarily stops operation of each circuit unit completely, that is, controls so as to be in a so-called standby state. Proceed to step S110.

Then, in step S110, the storage data amount D of the buffer memory 13 is checked, and in step S111, it is determined whether the storage data amount D of the buffer memory 13 is equal to or less than a predetermined storage data amount D3. The processing in steps S110 and S111 is as follows:
The process is performed until the accumulated data amount D of the buffer memory 13 becomes equal to or smaller than the predetermined accumulated data amount D3. When it is determined that the accumulated data amount D of the buffer memory 13 becomes equal to or smaller than the predetermined accumulated data amount D3, the process returns to step S101, The writing of the reproduction data to the memory 13 is restarted. The processing described above is executed until the reproduction operation ends. In addition,
At this time, it is needless to say that the reproduction data is continuously read from the buffer memory 13.

The accumulated data amount D3 is arbitrarily set according to the time required until the system controller 9 restarts the servo circuit 8 and the like from the standby state and executes the writing of the reproduced data to the buffer memory 13. And is set to be larger than the amount of data expected to be lost at that time.

That is, since the writing of the reproduction data into the buffer memory 13 is temporarily stopped completely after the time point t3 in FIG. 4, the amount of data stored in the buffer memory 13 gradually decreases. Then, at time t4 when the accumulated data amount D of the buffer memory 13 becomes equal to or less than the predetermined data amount D3 required for performing the continuous reproduction, the data reading unit 20 is driven again to reproduce the data in the buffer memory 13. By starting the data writing, the reproduced data is accumulated in the buffer memory 13 again. Then, the operation of stopping the writing of the reproduction data to the buffer memory 13 again at the time point t5 is repeatedly performed.

FIG. 5 is a diagram showing a state of current consumption consumed by the reproducing apparatus according to the present embodiment when the above-described reproducing operation processing is executed. As shown in FIG. 5, in the period from the time t1 to the time t3 when the buffer memory 13 is used as a shock-proof memory in the same manner as in the related art, during the period when writing / reading to / from the buffer memory 13 is performed, Data readout unit 20 including head 3, data temporary storage unit 30, and data temporary storage unit 30
Since the processing system block of the data read from is driven, the current consumption is Iw1.

In the period from the time point t1 to the time point t3, during which the data supply operation to the buffer memory 13 is not executed, the data reading unit 20 is in the standby state (pause state). Becomes As a result,
The average current consumption during the period from time t1 to time t3 is IA2, and this average current consumption IA2 corresponds to the average current consumption in the conventional reproducing apparatus.

On the other hand, at the time t3 when the writing to the buffer memory 13 is temporarily stopped after the time t3.
During the period from to time point t4, the operation of each circuit unit of the data read unit 20 is temporarily stopped at all and the standby state is established, so that the current consumption is Is.

As a result, the average current consumption after the time point t3 is, for example, considering the current consumption Iw1 when the data storage amount of the buffer memory 13 becomes equal to or less than the predetermined data flow D3 and the writing of the reproduction data is restarted. This is IA1 shown in FIG. That is, the average current consumption of the reproducing apparatus according to the present embodiment is IA1.

As described above, in the reproducing apparatus according to the present embodiment, when the accumulated data amount D of the buffer memory 13 reaches the maximum accumulated data amount Dmax after the start of the reproduction, the writing of the reproduced data to the buffer memory 13 is intermittent. Do it. Then, if the accumulated data amount D is maintained for the specific time Tth or more and the predetermined accumulated data amount D1 or more, the operation of the data reading unit 20 is temporarily stopped completely. Thereafter, when the accumulated data amount D becomes equal to or less than the predetermined accumulated data amount D3, the writing to the buffer memory 13 is restarted and the reproduced data is accumulated in the buffer memory 13. Such processing is repeated until the reproduction operation is completed.

As a result, the average current consumption of the reproducing apparatus according to the present embodiment is IA1, which can be reduced as compared with the current consumption IA2 of the conventional reproducing apparatus. Therefore, the power consumption during the reproducing operation is significantly reduced. The life of a built-in battery such as a dry battery can be dramatically extended.

Next, a reproducing operation according to a second embodiment of the present invention will be described with reference to the flowchart of FIG. 6 and the state of the amount of data stored in the buffer memory 13 of FIG.

Also in this case, for example, when the user performs a reproducing operation using the key operation unit 11, the reproducing operation of the optical disk 1 is started, and the system controller 9 reproduces the data from the data reading unit 20 as described with reference to FIG. A start-up process is executed (S200).

Next, in step S201, the system controller 9 resets / starts an internally provided timer and writes / reads reproduced data to / from the buffer memory 13 at a predetermined write / read bit rate. Control.

Then, in step S202, after checking the amount of data stored in the buffer memory 13,
Proceeding to step S203, whether data has been stored in the entire reproduction data storage area of the buffer memory 13, that is, whether the accumulated data amount D of the buffer memory 13 has reached the maximum accumulated data amount Dmax of the buffer memory 13 Determine.

Here, when it is determined that the accumulated data amount D of the buffer memory 13 has not reached the maximum accumulated data amount Dmax, the process returns to step S201, and step S201 is performed.
Execute the process from. If it is determined in step S203 that the accumulated data amount D of the buffer memory 13 has reached the maximum accumulated data amount Dmax, the process proceeds to step S20.
The process proceeds to step S4, where the timer value of the timer that has been reset and started in step S201 is held as Tx, and then proceeds to step S205 to reset / start the timer again. The above-described reproduction processing operation is performed from the time point t1 in FIG. 7 at which writing of the reproduction data to the buffer memory 13 is started to the time point t2 when the accumulated data amount D of the buffer memory 13 reaches the maximum accumulated data amount Dmax. Will be.

In step S206, control is performed such that reading of the reproduction data from the buffer memory 13 is continuously performed and writing of the reproduction data to the buffer memory 13 is performed intermittently. That is, the buffer memory 1
After the time t2 in FIG. 7 in which the accumulated data amount reaches the maximum accumulated data amount Dmax and the reproduction data is intermittently written, control is performed so that the reproduction data is written intermittently to the buffer memory 13. I do.

Then, in step S207, after checking the accumulated data amount D of the buffer memory 13, the process proceeds to step S208, and it is determined whether the accumulated data amount D of the buffer memory 13 is equal to or more than a predetermined accumulated data amount D1. Here, if the accumulated data amount D of the buffer memory 13 is not equal to or more than the predetermined accumulated data amount D1, the process returns to step S205, and the processing from step S205 is executed. Also,
When the accumulated data amount D of the buffer memory 13 is equal to or larger than the predetermined accumulated data amount D1, the process proceeds to step S209, and the timer value T that has been reset and started in step S205 is
It is determined whether the value is equal to or greater than a predetermined timer value Tth.

In step S209, if the timer value T is smaller than the specific timer value Tth, the process returns to step S206, and executes the processing from step S206. Such processing operation is performed by the timer value T in step S209.
Is determined to be equal to or greater than the specific timer value Tth. If it is determined in step S209 that the timer value T is equal to or greater than the specific timer value Tth, the process proceeds to step S210.

In the processing in steps S208 and S209, as described in the processing in steps S107 and S108 in FIG. 3, it is determined whether or not the reproduction data has been stably written to the buffer memory. In the case where the accumulated data amount D actually accumulated in the buffer memory has changed to be equal to or greater than the accumulated data amount D1 during the period from the time point t2 to the time point t3 after the elapse of the specific time in FIG. It is determined that the writing of the reproduction data to the memory 13 has been performed stably. That is, it is determined that the operation state does not require storing the reproduction data in the entire reproduction data storage area of the buffer memory 13.

Therefore, when the timer value T becomes equal to or greater than the predetermined timer value Tth in step S209, the process proceeds to step S210, and the system controller 9 temporarily stops writing the reproduction data to the buffer memory 13. To At this time, the system controller 9 temporarily stops the operation of each circuit unit simultaneously with turning off the laser output of the data reading unit 20, for example, as described in the process of step S109 in FIG.
Control is performed so as to be in a so-called standby state, and the process proceeds to step S211.

After checking the amount of data stored in the buffer memory 13 in step S211,
In step S212, it is determined whether or not the accumulated data amount D of the buffer memory 13 is equal to or less than a predetermined data amount D2. The processing in steps S211 and S212 is as follows.
The process is performed until the accumulated data amount D of the buffer memory 13 becomes equal to or smaller than the predetermined accumulated data amount D2. When it is determined that the accumulated data amount D of the buffer memory 13 becomes equal to or smaller than the predetermined accumulated data amount D2, the process proceeds to step S213. At this time, it is needless to say that the reproduction data is continuously read from the buffer memory 13.

The accumulated data amount D2 is the accumulated data amount D
As in the case of 3, the time is arbitrarily set depending on the time required until the servo circuit 8 and the like are restarted and the reproduction data is written into the buffer memory 13. However,
As will be described later, in the case of the present example, the speed of rewriting the reproduced data is set to be slow, so that the margin is set so that the accumulated data amount D2> the accumulated data amount D3.

Accordingly, the amount of data stored in the buffer memory 13 after the time point t3 in FIG. 7 gradually decreases because the writing of the reproduction data to the buffer memory 13 is temporarily stopped.

Next, in step S213, it is determined whether or not the timer value Tx previously held in step S204 is smaller than a preset timer value Ts.
That is, a timer value set in advance from the time when reproduction is started (time t1 in FIG. 7) to the time when the accumulated data amount D of the buffer memory 13 reaches the maximum accumulated data amount Dmax (time t2 in FIG. 7). It is determined whether it is smaller than Ts.

Here, when it is determined that the timer value Tx is smaller than the timer value Ts, the time when the accumulated data amount D of the buffer memory 13 becomes the maximum accumulated data amount Dmax from the reproduction operation start time (time t1 in FIG. 7). At (time t2 in FIG. 7), it is determined that the reproduction data has been stably written to the buffer memory 13 with little disturbance or the like, and the process proceeds to step S214. That is, the timer value Tx held in step S204 is used as history information indicating the status of reading data from the optical disc 1 first.

In step S214, the system controller 9 drives the data reading section 20 by controlling the rotation speed of the spindle motor 2 to be 1.2 to 1.5 times faster than 1 time. That is, when it is determined from the timer value Tx used as the history information that the writing of the reproduction data to the buffer memory 13 is being performed stably, the write bit rate to the buffer memory 13 is set to be smaller than the read bit rate. The writing of the reproduction data into the buffer memory 13 is restarted at a slightly slower speed.

That is, at time t4 in FIG. 7 when the accumulated data amount D becomes equal to or less than the predetermined data amount D2, the writing of the reproduced data to the buffer memory 13 is resumed at a write bit rate lower than the normal write bit rate. Will be done.
As a result, the reproduction data is stably written in the buffer memory 13, so that the reproduction data is accumulated.

Next, in step S215, the amount of data stored in the buffer memory 13 is checked, and in step S216, it is determined whether the amount D of data stored in the buffer memory 13 is equal to or less than a predetermined data amount D3. In step S216, if the accumulated data amount D of the buffer memory 13 is not less than the predetermined accumulated data amount D3, the process proceeds to step S217.

In step S217, it is determined whether or not the accumulated data amount D of the buffer memory 13 is equal to or greater than the maximum accumulated data amount Dmax. If the accumulated data amount D of the buffer memory 13 is equal to or less than the maximum accumulated data amount Dmax, step S2 is executed.
15, the process from step S215 is performed.
If the accumulated data amount D is equal to or larger than the maximum accumulated data amount Dmax, the process returns to step S205, and the processing from step S205 is executed. In this case, the process may return to step S210 and execute the processing from step S210.

On the other hand, when it is determined in step S213 that the timer value Tx is greater than the timer value Ts, or in step S216, it is determined that the accumulated data amount D of the buffer memory 13 is equal to or less than the predetermined accumulated data amount D3. In this case, the process proceeds to step S218, where the system controller 9 drives the data reading unit 20 by controlling the rotation speed of the spindle motor 2 to the normal speed (double speed).

That is, in step S213, when it is determined that the writing of the reproduction data to the buffer memory 13 is unstable due to the influence of disturbance or the like, or in step S21.
In step 6, when it is determined that the accumulated data amount D of the buffer memory 13 has decreased to a predetermined accumulated data amount D3 or less, the write bit rate to the buffer memory 13 is increased, and the process returns to step S201. Restart the writing of the reproduction data. The processing described above is executed until the reproduction operation ends.

FIG. 8 is a diagram showing a state of current consumption consumed by the reproducing apparatus according to the second embodiment when the reproducing operation processing shown in FIG. 6 is executed. As shown in FIG. 8, the average current consumption during the period from time t1 to t3 when the buffer memory 13 is used in the same manner as in the related art is IA2 as described in FIG.

On the other hand, after the time point t3, the current consumption during the period from the time point t3 when the writing to the buffer memory 13 is temporarily stopped completely to the time point t4 is Is, and the spindle motor 2 operates at 1.2 to 1. The current consumption when reading data from the optical disk 1 at 5 × speed is Iw2.

As a result, the average current consumption after time t3 is smaller than the average current consumption IA1 shown in FIG.
A1 '. That is, the average current consumption in the reproducing apparatus according to the present embodiment is IA1 '.

As described above, in the reproducing apparatus according to the second embodiment, after starting the reproducing operation, the buffer memory 13
The time Tx until the accumulated data amount D reaches the maximum accumulated data amount Dmax is stored as history information, and the data reading unit 2
If the accumulated data amount D becomes equal to or less than the predetermined accumulated data amount D2 when the operation of the zero is temporarily stopped completely, the rotation speed of the spindle motor 2 is set according to the timer value Tx used as the history information. By doing so, the bit rate for writing to the buffer memory 13 is set, and writing to the buffer memory 13 is resumed. The following processing is repeated until the reproduction operation is completed. As a result, the power consumption during the reproducing operation is further remarkably reduced, and the life of the built-in battery such as a dry battery can be drastically increased.

In this embodiment, the case where the present invention is applied to a reproducing apparatus has been described. However, the present invention is not limited to this, and the present invention can naturally be applied to a recording / reproducing apparatus compatible with a magneto-optical disk. Further, the present invention can be applied to a playback apparatus compatible with DAT (digital audio tape). In other words, the present invention can be applied to the case where a buffer memory is provided at the subsequent stage of the data reading means and double-speed reading from, for example, a CD or DAT is performed so that a certain amount of data is always accumulated in the buffer memory. is there.

[0077]

As described above, according to the reproducing apparatus of the present invention, as the buffer memory for the reproduction output data read from the data reading means, the read bit rate of the reproduction data per unit time is set to A storage unit that is set to be smaller than the storage bit rate of the reproduction data, and a time period in which the storage amount of the reproduction data in the storage unit reaches a certain storage amount and is maintained at a first storage amount or more. When the time reaches a specific time, the operation of the data reading means is completely stopped, so that the power consumption of the data reading means can be significantly reduced during the operation unnecessary period of the data reading means.

Further, in the reproducing apparatus of the present invention, when the operation of the data reading means is restarted, the write bit rate is set by setting the rotation speed of the spindle motor according to the history information. For example, when the influence of disturbance or the like is small, the driving power of the spindle motor can be reduced by making the rotation speed of the spindle motor slower than usual (double speed), thereby further reducing power consumption. be able to. Thereby, for example, the battery life of the battery in the portable reproducing apparatus can be significantly improved.

Further, the present invention can be realized by a conventionally used control system controller without adding a special circuit or the like, and the power consumption can be automatically reduced without the user's awareness. There is also an advantage that it can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram of a main part of a playback device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a write / read operation of a buffer memory.

FIG. 3 is a flowchart of a reproducing operation according to the first embodiment.

FIG. 4 is a diagram illustrating a state of an amount of data stored in a buffer memory according to the first embodiment.

FIG. 5 is a diagram showing a state of current consumption consumed by the first embodiment.

FIG. 6 is a flowchart of a reproducing operation according to a second embodiment.

FIG. 7 is a diagram showing a state of an amount of data stored in a buffer memory according to a second embodiment.

FIG. 8 is a diagram showing a state of current consumption consumed by the second embodiment.

[Explanation of symbols]

Reference Signs List 1 optical disk 2 spindle motor, 3 optical head 7 decoder, 8 servo circuit, 9 system controller, 12 memory controller, 13 buffer memory, 20 data reading section, 30 data temporary storage section

Claims (4)

[Claims] 1. Data reading means for reading data from a recording medium, storage means for holding reproduced data read by the data reading means, and control means for controlling operations of the data reading means and the storage means. Wherein the read bit rate of read data from the storage means per unit time is set lower than the write bit rate of read data to the storage means per unit time. Stops the operation of the data reading means when the time during which the storage amount of the reproduction data in the storage means reaches a certain storage amount and the time during which the storage amount is kept equal to or more than the first storage amount reaches a specific time, When the storage amount of the reproduction data in the storage unit becomes equal to or less than the second storage amount, control is performed so that the operation of the data reading unit is restarted. . 2. Data reading means for reading data from a recording medium, storage means for holding reproduced data read by the data reading means, and control means for controlling operations of the data reading means and the storage means. Wherein the read bit rate of read data from the storage means per unit time is set lower than the write bit rate of read data to the storage means per unit time. History information setting means for setting history information of a data read status from the storage means, wherein the control means sets the storage amount of the reproduced data in the storage means to a first storage amount or more after the storage amount reaches a certain storage amount. When the held time reaches a specific time, the operation of the data reading means is stopped, and the storage amount of the reproduction data in the storage means becomes equal to or less than the second storage amount. Then, a reproduction bit rate of the reproduction data to the storage means is set according to the history information, and control is performed so as to restart the operation of the data reading means. 3. The reproducing apparatus according to claim 2, wherein the control unit sets the write bit rate by setting a rotation speed of a spindle motor. 4. The reproducing apparatus according to claim 2, wherein the history information setting means measures an accumulation time when the reproduction data is accumulated in the storage means, and uses the measured time as history information. .