JP2003173662A - Signal processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shorten a reading time in the case of reproduction by retaining TOC (table of contents) information also in a sleep mode. <P>SOLUTION: This processor has a signal processing part 20 which is supplied with a reproduction signal outputted from a reproducing amplifier, a volatile memory means 30 which has a shock proof function for storing the reproduction signal supplied via this signal processing part and which needs any-time write and read storage holding operation, a control part 40 comprising a microcomputer for controlling the signal processing part and the memory means, and a switching means 50 for switching a status signal from the signal processing part and the control part. Reproduction TOC information is stored in the memory means to control the supplying state of an operation power source so as to be in the sleep mode except for the control part and the memory means in a stopping mode, and the memory means is controlled to be in a self refresh mode with status signals CRAS, CCAS and WE from the control part. Thus, the TOC information can be retained also in the sleep mode and time until starting of reading TOC information is shorten. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal processing apparatus suitable for application to an electronic device using an optical disk such as an MD player. Specifically, when the TOC information already reproduced from the optical disk is stored in the volatile memory means by using the self-refresh mode, when the reproduction mode is selected from the state of transition to the low power consumption mode. However, it is possible to immediately play back music and the like.

[0002]

2. Description of the Related Art A battery-driven electronic device using an optical disk, such as an MD player, is equipped with a function capable of transitioning to a low power consumption mode (low power consumption function, so-called sleep function) in order to extend battery life. There is something.

This is to reduce the power consumption when the operation such as the stop mode is not being executed even when the operation is in progress. For example, in the MD player or the like, the operation is restored when the reproduction mode is switched to the stop mode. The normal operating power supply is supplied only to the minimum circuit system necessary for the above, and the supply of the power is stopped or the minimum voltage is applied to other circuits. In many cases, the circuit system other than the control unit, which is usually constituted by a microcomputer, is controlled so that even the memory means for holding data is in the sleep mode.

[0004]

In the signal processing device equipped with the function capable of transitioning to such a low power consumption mode,
When returning from the stop mode to the reproduction mode, there is a problem that the reproduced sound is not immediately output.

Describing with reference to the MD player, when the optical disc is loaded into the main body of the apparatus, TOC (Table of Contents) information recorded in the lead-in area of the optical disc is read out and stored in the memory means. Move the optical pickup means by referring to the saved TOC information,
Playback processing corresponding to the operation key is performed from the optical disc.

Since this TOC information is normally stored in the memory means described above, when the sleep mode is entered by the stop operation, this TOC information is also lost.

Therefore, since the TOC information to be referred to does not exist even when the mode is changed to the reproduction mode, the control unit again controls the TOC.
The process for reading information is started. Then, this TOC information is read out, stored in the memory means, and then the optical pickup means is further moved to the designated position, and then the reproduction signal is read out.

For these reasons, it takes a considerable time (6 to 8 seconds in some cases) until the reproduced sound is actually output even when the reproduction mode is selected. During that time, the user cannot listen to music or the like, which may lead to misunderstanding that an operation error has occurred. It can also cause irritation. In order to solve these problems, it is preferable that the waiting time until the music or the like is reproduced be as short as possible. If possible, it is preferable that music or the like be played at the same time when the play key is operated.

Therefore, the present invention solves the conventional problems as described above, and proposes a signal processing device which allows music or the like to be reproduced as quickly as possible, especially when a transition is made to the reproduction mode. To do.

[0010]

In order to solve the above problems, in the signal processing apparatus according to the present invention as set forth in claim 1, a signal processing unit to which a reproduction signal reproduced from an optical disk is supplied, and this signal processing unit. Volatile memory means having a shock-proof function for storing the reproduction signal supplied through the processing section and requiring an occasional write and read storage holding operation, and at least the optical disk, the signal processing section, and the volatile memory A TOC reproduced from the optical disc, which has a control unit composed of a microcomputer for controlling the means, and a switching unit for switching status signals to the volatile memory means supplied from the signal processing unit and the control unit. Information is stored in the volatile memory means, and when the stop mode is selected, the control unit and the volatile memory are The supply state of the operating power is controlled so as to be in the sleep mode in which the power supply is not performed except for the stage, and the status signal from the signal processing unit is switched to the status signal from the control unit by the switching unit. It is characterized in that the volatile memory means is controlled to a self-refresh mode for holding data.

In the present invention, in order to prevent skipping of the reproduction signal from the optical disk, the memory means used for temporarily storing the reproduction signal to realize the shock proof function is also used as the memory means for the TOC information. To do.

Since this memory means normally uses a volatile memory means such as a DRAM which requires a write and read storage holding operation at any time, the volatile memory means is in an operating state even when transitioning to the sleep mode. Controlled as. Then, the self-refresh function of the volatile memory means is used to hold the data in the sleep mode.

Since the data in the volatile memory means can be held even in the sleep mode, the TOC information held in the volatile memory means is immediately referred to when the optical disk is read when the stop mode is changed to the reproduction mode by a key operation. Can be played. As a result, it is possible to avoid the problem that the reproduced sound is not output for a long time after the reproduction mode is entered. The waiting time can be shortened to less than half of the conventional one. This is to save the time for reading the TOC information again.

Information of the read address of the memory means in the stop mode and address information of the optical pickup means on the optical disc are respectively stored, and a so-called resume function is added so that the address can be used for reproduction. In such a case, the data held in the memory means of the shock proof function can be immediately utilized for reproduction, and in this case, the reproduction sound can be heard at the same time when the reproduction mode is selected. In other words, the waiting time until the playback sound is heard can be reduced to almost zero.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of a signal processing device according to the present invention will be described in detail with reference to the drawings.
In the present invention, an MD player is exemplified as an electronic device using an optical disc. FIG. 1 is a system diagram of a main part of a signal processing device 10 showing a reproducing system in an MD player to which the present invention is applied.

The optical disk 12 is rotationally driven by a spindle motor 14 so as to have a predetermined rotational speed. An optical pickup means 16 is arranged directly below the optical disk 12 so as to be slidable in the radial direction, and the return light obtained by irradiating a laser from the optical pickup means 16 is converted into an electric signal (reproduction signal). This reproduction signal is supplied to the signal processing unit 20 via the reproduction amplifier 18.

As the signal processing unit 20, a DSP is used in this example.
(Digital Signal Processor) is used. As will be described in detail later, this includes volatile memory means 30.
Are connected, the compressed reproduction signal is temporarily stored in the volatile memory means 30, and the reproduction signal is sequentially read from the time when a predetermined amount is stored, and the signal processing unit 20 is connected.
Decompression and demodulation processing is performed in the
The conversion circuit 32 restores the analog signal. The reproduction signal converted into the analog signal is supplied to the output amplifier 34 and the speaker 36, and the signal such as music is reproduced.

Since the signal reading process for the optical disk 12 and the signal reproducing process can be separated by interposing the volatile memory means 30, no sound skip occurs even if there is a disturbance or the like. That is, the shock proof operation can be realized by using the volatile memory means 30.

The key input information from the key operation unit 38 is supplied to a control unit 40 which is composed of a microcomputer and controls the entire apparatus, and an operation mode corresponding to the key operation is executed.
Further, various servo signals (rotation servo signal, tracking control signal, focus control signal, etc., which are generated based on the reproduction signal) output from the signal processing unit 20 are supplied to the motor driver 42 and the optical pickup means 16. Then, drive control for the spindle motor 14 and tracking control for the optical pickup means 16 are executed.

As the above-mentioned volatile memory means 30,
A memory means, such as a DRAM, which requires write and read storage holding operation at any time is used. As the volatile memory means 30, one having a self-refresh function is particularly used. By using the self-refresh function, the stored data can be retained without being lost even in the sleep mode.

To realize the self-refresh function,
In the normal case, it is necessary to perform preprocessing immediately after the start of the self-refresh mode and post-processing immediately after the end of the self-refresh mode. Normal refresh mode DSP
This is performed by the status signal generated by the signal processing unit 20 of the configuration. Here, the status signal is a signal including at least a row address strobe signal CAS, a column address strobe signal RAS, and a write enable signal WE.

On the other hand, when the device is driven in the low power consumption mode (sleep mode), the operating power is supplied only to the minimum necessary circuit system, and the power supply to the other circuit systems is stopped so that the circuit system is stopped. Power supply is controlled. Therefore, in this invention, when transitioning to the sleep mode,
In addition to the control unit 40 composed of a microcomputer, only the above-mentioned volatile memory means 30 is supplied to the operating power supply to realize the above-mentioned low power consumption mode.

When such control is performed, in the low power consumption mode, the signal processing unit 20 also enters the sleep mode, so that the signal processing unit 20 for controlling the operating state of the volatile memory means 30 operates. The status signal is also interrupted, so that the volatile memory means 30 cannot transition to the self-refresh mode at the stage of entering the sleep mode, and the information stored in the volatile memory means 30 is retained during the sleep mode. I can't keep it.

Therefore, in the present invention, a status signal switching means 50 is further provided between the signal processing section 20 and the control section 40 and the volatile memory means 30 described above. The switching unit 50 supplies the status signal generated by the control unit 40 to the volatile memory unit 30 and executes the self-refresh mode only when the sleep mode starts and ends.

FIG. 2 is an embodiment showing the details.
The signal processing unit 20 will be described first. The signal processing unit 20 is configured by the DSP as described above, and the one configured so as to realize at least the functions described below is used inside thereof.

First, the information recorded on the optical disk 12 is compressed information, and is an ATRAC (Adaptive Trans
Information compression processing is performed using a compression technique called form acoustic coding. Therefore, the decoder 2 for that purpose
2 is provided in the signal processing unit 20.

A portable electronic device such as an MD player has a shock proof function in order to prevent the sound skipping caused by an external impact. This shock proof function is performed by using the volatile memory means 30. The reproduction signal from the optical disk 12 is temporarily stored in the volatile memory means 30, and the stored reproduction signal is expanded and demodulated to obtain an analog reproduction signal. ing. Therefore, a controller 24 is provided for performing decompression and demodulation processing and generating various status signals to be given to the volatile memory means 30.

As the status signal, a row address strobe signal CAS (DCAS), a column address strobe signal RAS (DRAS) and a write enable signal W are used.
E (DWE) is shown.

In addition to these signal processing systems, the signal processing section 20 controls the drive state of the optical disk 12 and the focus control and tracking control of the optical pickup means 16 based on the reproduction signal. A servo controller 26 for generating is built in.

Also in the control unit 40, status signals used by the volatile memory means 30, especially status signals used for pre-processing and post-processing in the self refresh mode (row address strobe signal CAS (CRAS) and column). Address strobe signal RAS (CCAS))
And a switching signal B for controlling the switching means 50.
A signal generating means for generating UP is provided, but its details are omitted. The signal processor 20 is controlled by the controller 40.

Further, in the control unit 40, memory means (RAM or the like) for storing calculation data related to TOC information.
42 are provided. This operation data is check data used to check whether the TOC information to be saved has been destroyed during the sleep mode.

Therefore, the TOC information stored in the volatile memory means 30 is read and the read TOC information is supplied to the control section 40 via the signal processing section 20 before the pre-processing in the self-refresh mode. Control unit 40
Then, a 2-byte operation output (operation data) obtained by adding a part or all of the digital data forming the TOC information is stored in the memory means 42 as check data.

Then, at the stage where the post-processing in the self-refresh mode is performed, the TOC information stored in the volatile memory means 30 is read again, and the same arithmetic processing is performed, and the result obtained is stored in the memory means 42. Compare with the check data. As a result, when they match, the TOC information stored in the volatile memory means 30 is regarded as correct and this TOC information is continuously used.

On the other hand, when they do not match, it is considered that the TOC information stored in the volatile memory means 30 is not accurate. Therefore, in this case, the TOC information is read again from the optical disk 12 and the TOC information is read. The process of storing in the volatile memory means 30 is performed.

This check data is information (actual data such as music information) stored in the volatile memory means 30.
However, it can also be used as data to check whether it has been destroyed during the sleep mode. TO
This is because when the C information is destroyed, it is considered that there is a high probability that the actual data is also destroyed.

When the stop key is further operated, the memory means 42 stores the address information of the reproduction signal immediately before that. TOC information is used as this address information. In this case, the stop address at the time of operating the stop key and the final address written in the shockproof volatile memory means 30 are the memory means 4 described above.
Stored in 2.

By storing the address information in this way, when the next reproduction mode is entered, reproduction can be started from the stop address. Such a function is called a resume function. When the reproduction mode is selected by the resume function, it is possible to shorten the time from the stopped position until the music or the like is reproduced.

Referring again to FIG. 2, the data from the signal processing unit 20 is directly supplied to the volatile memory means 30, and the status signals DRAS, DCAS, DWE from the signal processing unit 20 are switched. Means 50
Is supplied to the corresponding terminal a. Similarly, the above-mentioned status signals CRAS, CCAS generated by the control unit 40 are generated.
Is also supplied to the corresponding terminal b of the switching means 50. However, since the write enable signal WE is not output from the control unit 40, the corresponding terminal b is pulled up to the power supply voltage VDD. The status signal extracted from the switching means 50 is supplied to the corresponding input terminal of the volatile memory means 30.

When the sleep mode is selected,
The switching unit 50 is switched and controlled by the switching signal BUP so that the status signal on the control unit 40 side is output.

Now, the above-mentioned processing can be summarized as shown in FIG. This will be described with reference to FIG. In FIG. 3, the reproduction mode operation, the stop mode operation, and the reproduction mode operation are described in time series.

When the normal reproduction mode is changed to the stop mode (FIG. 3A), the reading of the actual data from the volatile memory means 30 is stopped, and the check data calculation mode is set immediately after the stop key is operated, and the volatile memory is reached. The TOC information is read from the means 30 and the addition processing of the data is performed (FIG. 3G). The check data obtained by the addition processing is stored in the memory means 42 of the control unit 40 (FIG. 3H).

When the check data calculation mode ends,
The status signal on the control unit 40 side is switched by the switching signal BUP (FIG. 3C). As a result, the pre-processing mode of the self refresh mode is set. The pre-processing mode is a refresh process for all the memory cells, and in the case of a 4 Mbit DRAM, the refresh process is performed 1024 times by the column address strobe signal RAS (CRAS) (FIG. 3D).

At this time, the row address strobe signal CA
S (CCAS) is controlled to a low level and the write enable signal WE is controlled to a high level (pull-up level) (FIGS. 3E and 3F). After this pre-processing is completed, the volatile memory means 30 starts self-refresh,
The device transits to the original sleep mode in the state where data retention is secured.

When the reproduction key is operated while the sleep mode continues (FIG. 3B), the self-refreshing post-processing mode is entered. In the post-processing mode as in the pre-processing, all memory cells are refreshed by the column address strobe signal RAS (CRAS) and the row address strobe signal CAS from the control unit 40.
(CCAS) and the pull-up write enable signal WE (FIG. 3D, E, F).

When the post-processing is completed, the switching signal BUP
By this, the status signal is switched to the signal processing unit 20 side, and at the same time as this switching, the status signal transits to the TOC information check mode. In this check mode, TOC information is read from the volatile memory means 30 and addition processing is performed. A comparison process is performed between the result of the addition process and the operation data stored in the memory means 42 (FIG. 3I).

As a result of the comparison, when the data match is found, the mode is changed to the reproduction mode in which the TOC information stored in the volatile memory means 30 is used as it is. In the stop mode, the optical pickup means 16 is at the position at the time of stop and stores the position of the address to be reproduced by the resume function. Therefore, at the same time when the reproduction key is operated,
Music or the like is played using the data from the volatile memory means 30. That is, upon transition to the reproduction mode, the next reproduction sound can be heard immediately from the position set to the stop mode.

When the data do not match, it is considered that the TOC information is destroyed for some reason after entering the sleep mode. In this case, the optical pickup means 16 is moved to read the TOC information from the optical disk 12. It is stored in the volatile memory means 30. And
The reproduction process is executed from the beginning by using the read TOC information.

Therefore, in this case, since the music and the like are reproduced at the stage where the information so far is initialized and the TOC information read processing is completed, the music and the like from the first music is slightly delayed from the transition to the reproduction mode. Will be played.

FIGS. 4 and 5 are flowcharts showing an example of the processing procedure for realizing the above operation. First, referring to FIG. 4, an operation mode corresponding to the operation key is executed (step 60), and during the process, for example, when the stop key is operated during a transition to the reproduction mode (step 61), volatilization is performed. The actual data reading in the local memory means 30 is stopped (step 6
2) The mode is changed to the check data calculation mode, the TOC information read from the volatile memory means 30 is processed, and the result is stored in the memory means 42 (step 6).
3, 64).

Next, the status signal is switched to the control section 40 side to execute the pre-process of the self-refresh mode, and then the self-refresh mode is entered (step 6).
5, 66). When the reproduction key is pressed in this state (step 67), post-processing of the self-refresh mode is executed to cancel the self-refresh mode (step 68).

When the self-refresh mode is released, the status signal is switched to the signal processing section 20 as shown in the flowchart of FIG. 5, and the mode is changed to the check mode to execute the TOC information reading and the arithmetic processing. (Steps 71, 72).

This calculation result is compared with the stored check data, and if they match, the TOC information stored in the volatile memory means 30 is used to determine the actual data in the volatile memory means 30. Is resumed and the reproduction process is performed (steps 73 and 74). If they do not match, the TOC information is read again from the optical disk 12 and used for reproduction processing (steps 73 and 75).

As described above, according to the present invention, TOC information can be stored even in the sleep mode.
Since the time for re-reading the information can be shortened, the time between the transition to the reproduction mode and the output of music or the like can be shortened to less than half of the conventional time.

Further, by stopping the reading of the actual data along with the stop operation and restarting the reading of the actual data along with the reproducing operation, the time until the music or the like is output is further shortened, and the mode is changed to the reproducing mode. Music and the like can be reproduced and output almost at the same time as the transition of. That is, the waiting time can be reduced to almost zero.

In addition to such a function, when the TOC information check mode is added, even if the TOC information is destroyed at the time of transition to the self-refresh mode, it is possible to appropriately deal with it. In the above-mentioned embodiment, the DRAM is exemplified as the volatile memory means 30, but the present invention is not limited to this. The electronic device to be applied is not limited to the MD player.

[0056]

As described above, according to the present invention, in the signal processing device of the electronic equipment in which the low power consumption mode is incorporated, the TOC information can be stored even when the low power consumption mode is entered. Since it is possible to immediately output the reproduced sound when transitioning from the to the reproduction mode, there is an effect that the time until the reproduced sound is output can be significantly shortened as compared with the conventional case.

As the memory means for storing the TOC information, the volatile memory means used for the shockproof function can be used, so that the cost is not increased. TOC
When the information check function is provided, there is a feature that it is possible to surely avoid a mistake such as performing a reproduction process based on incorrect TOC information. Therefore, the present invention is extremely suitable when applied to a signal processing device of a portable electronic device such as an MD player.

[Brief description of drawings]

FIG. 1 is a system diagram of essential parts showing an embodiment when a signal processing device according to the present invention is applied to an MD player.

FIG. 2 is a detailed system diagram of a part thereof.

FIG. 3 is a waveform diagram for explaining the operation.

FIG. 4 is a flowchart showing an embodiment for realizing a reproduction process following the self-refresh mode (No. 1).

FIG. 5 is a flowchart showing an embodiment for realizing a reproduction process following the self-refresh mode (No. 2).

[Explanation of symbols]

10 Signal processing device 12 Optical disc 16 Optical pickup means 20 Signal processing unit (DSP)) 30 Volatile memory means 40 control unit 50 switching means RAS, CAS, WE status signal BUP switching signal

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 5D044 BC03 BC06 CC06 DE54 DE91                       EF03 EF05 FG10 FG18 GK12                 5D077 AA30 BA05 BA19 CA02 DC08                       DE13 DF03 EA08 EA34                 5D110 AA17 AA19 AA27 BB01 DA01                       DA12 DB08 DC06 DE01 EA06                       EA17

Claims (7)

[Claims] 1. A signal processing unit to which a reproduction signal reproduced from an optical disk is supplied, and a write-on / write-out memory holding function having a shock-proof function for storing the reproduction signal supplied via the signal processing unit. Volatile memory means that needs to operate, a control section that is composed of at least the optical disk, the signal processing section, and a microcomputer that controls the volatile memory section, and the signal processing section and the control section that respectively supply the above. Switching means for switching status signals to the volatile memory means, TOC information reproduced from the optical disc is stored in the volatile memory means, and when the stop mode is selected, the control unit and the volatile memory means If the operating power supply state is controlled so that it goes into the sleep mode where power is not supplied except for In addition, the status signal from the signal processing unit is switched to the status signal from the control unit by the switching unit to control the volatile memory unit in a self-refresh mode for storing and holding. Signal processing device. 2. The signal processing device according to claim 1, wherein the status signal includes at least a row address strobe signal and a column address strobe signal. 3. The signal processing apparatus according to claim 1, wherein the self-refresh mode includes a pre-processing mode and a post-processing mode for self-refreshing. 4. The memory means provided in the control section stores the address of the reproduction signal when the stop mode is selected and the final address of the reproduction signals stored in the volatile memory means. 2. The signal processing apparatus according to claim 1, wherein the resume operation is performed. 5. Just before the stop mode is selected and transitions to the pre-processing mode of the self-refresh mode,
2. The signal processing apparatus according to claim 1, wherein the control unit is provided with a storage unit for storing a calculation output obtained by reading the TOC information from the volatile memory unit. 6. When a reproduction mode is selected during the self-refresh mode, when the post-processing mode ends, the TOC information is read out and stored in the storage means. The control unit is provided with a data check processing function for comparing the calculated output with the calculated output, and the TOC information stored in the volatile memory means is used only when the calculated outputs match each other. The signal processing device according to claim 5. 7. The signal processing apparatus according to claim 6, wherein reading of the reproduction signal from the volatile memory means is stopped in the sleep mode.