JPH06150551A - Disk reproducing device - Google Patents

Abstract

PURPOSE:To output not only an audio reproduced from a disk but digital audio data inputted from the outside as well by converting to an analog audio signal. CONSTITUTION:A compact disk 1 is rotated by a spindle motor 3, and the regenerated data is outputted from a digital signal processing circuit 7. The outputted digital audio data 20 are recorded temporarily in a buffer RAM circuit 11 and outputted to a D/A converter circuit 12. Then, the data are converted to an analog audio signal by the D/A converter circuit to be outputted to the outside. Further, the digital audio data inputted from the outside are recorded temporarily in the buffer RAM circuit 11 to be outputted to the D/A converter circuit 12 as well. Then, the data are converted to the analog audio signal by the D/A converter circuit to be outputted to the outside.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc reproducing apparatus, particularly a CD-ROM player, for reproducing data and voice by using a disc-shaped information recording / reproducing medium.

[0002]

2. Description of the Related Art A compact disc reproducing device is shown as an example of a conventional disc reproducing device.

FIG. 3 is a block diagram showing a conventional disc reproducing apparatus, and FIG. 4 is a block diagram showing the digital signal processing circuit of FIG.

In FIG. 3, reference numeral 1 is a compact disc as a record carrier. This compact disc 1
The data recorded on the disk is rotated by the spindle motor 3 and taken out by the optical pickup 2.

Reference numeral 5 denotes a waveform shaping circuit, which shapes the analog reproduction signal output from the optical pickup 2 into a binary signal. The binarized data thus obtained is output to the digital signal processing circuit 9.

As shown in FIG. 4, the digital signal processing circuit 9 includes a synchronization detection circuit 41, a PLL circuit 42, a demodulation circuit 43, a crystal oscillation circuit 44, and a sub-coding detection circuit 4.
5, RAM (Random Access Memory) 46.

In FIG. 4, a synchronization detection circuit 41 detects frame synchronization from the binarized data output from the waveform shaping circuit 5.

PLL (Phase Locked Loop) circuit 42
Regenerates the clock from the binarized data.

The demodulation circuit 43 takes in a digital signal from the synchronization detection circuit 41 and outputs a CIRC (Cross Interleave R) signal.
An error is detected and corrected by an eed-Solomon code), and digital audio data 21 or digital data 23 demodulated by a reproduction timing signal given from a crystal oscillator circuit 44 is output.

The sub-coding detection circuit 45 reproduces the disk address information 24 and the like for performing track positioning.

The RAM 46 functions as a buffer for CIRC deinterleaving and error correction.

Further, in FIG. 3, reference numeral 10 denotes a servo circuit, which has two kinds of clocks output from the digital signal processing circuit 9 (a reference clock output from the crystal oscillation circuit 44 and a reproduction clock output from the PLL circuit 42). Control is performed so that the rotation speed of the spindle motor 3 matches the reference clock. Further, the slide motor 4 and the optical pickup 2 are controlled based on the access control signal 25 output from the access control device 8.

The access control device 8 controls the slide motor 4 and the optical pickup 2 via the servo circuit 10 based on the disk address information 24 output from the digital signal processing circuit 7 to perform track positioning.

Reference numeral 12 denotes a D / A conversion circuit, which is digital audio data 2 output from the digital signal processing circuit 7.
1 is converted into an analog voice signal 22 and output.

[0015]

The conventional CD player described above merely converts the digital audio data reproduced from the disc into an analog audio signal and outputs the analog audio signal, and inputs the digital audio data from the outside into an analog audio signal. It could not be converted and output. Therefore, for example, it has been impossible to input digital voice data from a host computer, convert it into an analog voice signal, and output it.

Further, it has been impossible to send the digital audio data reproduced from the disc to the host computer, process it, and then return it to the CD player to output it as an analog audio signal.

It is an object of the present invention to provide a disc reproducing apparatus capable of converting not only the voice reproduced from a disc but also digital voice data inputted from the outside into an analog voice signal and outputting the analog voice signal.

[0018]

In order to solve the above-mentioned problems, according to the present invention, a buffer RAM for temporarily storing digital audio data reproduced from a disk or digital audio data input from the outside, A buffer RAM control device is provided in which these digital voice data are sequentially written in the buffer RAM and the written digital voice data is read at a predetermined transfer rate.

[0019]

According to the present invention, the digital voice data inputted from the outside is once written in the buffer RAM, the written digital voice data is read out at a predetermined transfer rate, converted into an analog voice signal and outputted.

Therefore, it is possible to provide a disc reproducing apparatus capable of converting not only the voice reproduced from the disc but also the digital voice data inputted from the outside into an analog voice signal and outputting the analog voice signal.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a first embodiment of the present invention, and FIG. 2 is a block diagram showing the digital signal processing circuit of FIG. In FIG. 1, 1 is a compact disc as a record carrier. This compact disc 1
Is rotated by the spindle motor 3 at a constant linear velocity, double the linear velocity, or a constant rotational velocity. An optical pickup 2 takes out data recorded on the disc as an analog reproduction signal.

Reference numeral 5 is a waveform shaping circuit, which shapes the analog signal output from the optical pickup 2 into a binary signal. The binarized data thus obtained is output to the digital signal processing circuit 7.

The digital signal processing circuit 7 reproduces a clock from the binarized data output from the waveform shaping circuit 5, demodulates the digital data 20 and outputs it. Also,
The disk address information 24 is output. The details of the digital signal processing circuit 7 will be described later. The digital data 20 is output in synchronization with the clock reproduced from the compact disc 1.

If the digital data 20 is not digital voice data, it is output to the outside as it is. When the digital data 20 is digital voice data, it is output to the buffer RAM 11. However, even when the digital data 20 is digital voice data,
It can also be output directly to the outside.

The buffer RAM 11 temporarily stores the digital voice data 20 and outputs the digital voice data 21 at a predetermined transfer rate to the D / A conversion circuit 12. Alternatively, the digital voice data 20 input from the outside is temporarily stored in the buffer RAM 11, and then the digital voice data 21 having a predetermined transfer speed is converted into the D / A conversion circuit 1.
Output to 2.

Reference numeral 13 is a RAM controller, which is a buffer R
It controls the input / output timing and address of the AM 11. Further, the RAM control device 13 has a built-in reference clock and controls the buffer RAM 11 to output the digital audio data 21 at a predetermined transfer rate.

The D / A conversion circuit 12 includes a buffer RAM 1
The digital voice data 21 output from 1 is converted into an analog voice signal 22 and output.

The servo circuit 6 controls the rotation speed of the spindle motor 3. Further, the slide motor 4 and the optical pickup 2 are controlled based on the access control signal 25 output from the access control device 8.

The access control device 8 controls the slide motor 4 and the optical pickup 2 via the servo circuit 6 based on the disc address information 24 output from the digital signal processing circuit 7 to perform track positioning.

Details of the digital signal processing circuit 7 will be described below with reference to FIG. The digital signal processing circuit 7 includes a synchronization detection circuit 41, a PLL circuit 42, a demodulation circuit 47, a subcoding detection circuit 45, and a RAM 46.

In FIG. 2, the synchronization detection circuit 41 detects frame synchronization from the input binarized data and outputs it to the demodulation circuit 47.

The PLL circuit 42 reproduces a clock from the input binarized data and outputs it to the demodulation circuit 47.

The demodulation circuit 47 takes in a digital signal from the synchronization detection circuit 41 and uses the RAM 46 to perform CIRC.
Deinterleaving and error detection and correction by CIRC are performed. Then, the demodulated digital data 20 is output. The digital data 20 is output in synchronization with the clock reproduced by the PLL circuit 42.

The sub-coding detection circuit 45 reproduces the disc address information 24 for performing track positioning.

With the above-mentioned structure, in this embodiment,
The digital data reproduced from the disk is output to the outside, the digital audio data reproduced from the disk is passed through the buffer RAM, and then converted into an analog audio signal for output. Also, the digital audio data input from the outside is once written in the buffer RAM, the written digital audio data is read at a predetermined transfer rate, and D / A
It is sent to the conversion circuit, converted into an analog audio signal and output.

Therefore, not only the sound reproduced from the disk but also the digital sound data inputted from the outside can be converted into the analog sound signal and outputted. Also,
The digital audio data reproduced from the disc can be output to the outside, processed externally, re-input to the disc reproducing apparatus, converted into an analog audio signal and output. Further, by outputting the digital audio data reproduced from the disc to the outside and storing the digital audio data in an external storage device, the stored digital audio data is always stored regardless of the reproduction state of the disc. The voice data can be called, converted into an analog voice signal and output.

FIG. 5 is a block diagram showing a second embodiment of the present invention. The second embodiment is the same as the first embodiment except that a buffer RAM 14 and a mixing circuit 15 are added.

The buffer RAM 11 temporarily stores the digital audio data 20 reproduced from the disk, and mixes the digital audio data 21 at a predetermined transfer rate with the mixing circuit 1.
Output to 5.

The buffer RAM 14 temporarily stores the digital voice data inputted from the outside, and outputs the digital voice data 27 having a predetermined transfer rate to the mixing circuit 15.

Reference numeral 13 is a RAM controller, which is a buffer R.
It controls input / output timings and addresses of the AMs 11 and 14. Further, the RAM control device 13 has a built-in reference clock, and controls the buffer RAMs 11 and 14 to output the digital audio data 21 and 27 at a predetermined transfer rate.

The mixing circuit 15 adds 27 to the digital voice data 21 to change the output level.

FIG. 6 shows the mixing circuit 15.

Reference numeral 50 is an attenuator, which is a buffer RAM1.
It is possible to change the balance and level of the L channel and the R channel of the digital audio data 21 and 27 of the 1 and 14 outputs, respectively.

Reference numeral 51 denotes an adder, which adds L channels and R channels, outputs both channels of one-channel audio,
The L channel and the R channel can be exchanged. The mixing circuit 15 applies these processes to the input digital audio data, and then outputs it to the outside.

In FIG. 5, the D / A conversion circuit 12 converts the digital audio data output from the mixing circuit 15 into an analog audio signal 22 and outputs it.

With the above configuration, in this embodiment,
Digital audio data input from the outside can be temporarily written in the buffer RAM, added with the digital audio data reproduced from the disk, and then converted into an analog audio signal and output.

Therefore, by inputting a sound effect or the like from the outside while reproducing the sound from the disc, the added sound can be output.

In this embodiment, the case where the number of the buffer RAMs is two has been described as an example, but the number of the buffer RAMs can be one or three, and the number is not particularly limited.

FIG. 7 is a block diagram showing a third embodiment of the present invention. The third embodiment is an ADPCM processor 16
Is the same as the first embodiment except that is added. A
The DPCM processor expands compressed audio data.

The buffer RAM 11 temporarily stores the ADPCM audio data 20 reproduced from the disc, and outputs the digital audio data 21 having a predetermined transfer rate to the ADPCM processor 16. Or AD input from outside
The PCM voice data 20 is temporarily stored in the buffer RAM 11, and then the digital voice data 21 having a predetermined transfer rate is output to the ADPCM processor 16.

The ADPCM processor 16 receives the input A
The DPCM audio data is expanded and output.

The D / A conversion circuit 12 converts the digital audio data output from the ADPCM processor 16 into an analog audio signal 22 and outputs it.

With the above configuration, in this embodiment,
The ADPCM audio data reproduced from the disk is expanded by the ADPCM processor via the buffer RAM, converted into an analog audio signal, and output. The ADPCM audio data input from the outside is also expanded by the ADPCM processor via the buffer RAM, converted into an analog audio signal, and output.

Therefore, the ADPCM reproduced from the disc
In addition to voice, ADPCM voice data input from the outside can be converted into an analog voice signal and output.

Further, the ADPCM audio data reproduced from the disc can be output to the outside, processed externally, re-input to the disc reproducing apparatus, converted into an analog audio signal and output.

[0057]

Since the present invention is constructed as described above, it has the following effects.

That is, the digital audio data input from the outside is once written in the buffer RAM, and the written audio data is read out and output at a predetermined transfer rate, so that not only the audio reproduced from the disk but also the external input The generated digital voice data can also be converted into an analog voice signal and output.

Further, the digital audio data reproduced from the disc can be transferred to an external device such as a host computer, subjected to processing, and then returned to the disc reproducing device again to be converted into an analog audio signal for output.

[Brief description of drawings]

FIG. 1 is a block diagram showing a disc reproducing apparatus according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a digital signal processing circuit of the first embodiment.

FIG. 3 is a block diagram showing a conventional disc reproducing apparatus.

FIG. 4 is a block diagram showing a conventional digital signal processing circuit.

FIG. 5 is a block diagram showing a disk reproducing device of a second embodiment.

FIG. 6 is a block diagram showing a mixing circuit of a second embodiment.

FIG. 7 is a block diagram showing a disk reproducing device of a third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Compact disc, 2 ... Optical pickup, 3 ... Spindle motor, 4 ... Slide motor, 5 ... Waveform shaping circuit, 6 ... Servo circuit, 7 ... Digital signal processing circuit, 8 ... Access control device, 11 ... Buffer RAM, 12 ... D / A conversion circuit, 13 ... RAM control device.

Claims (2)

[Claims] 1. A disc reproducing apparatus for reproducing data from a signal recorded on a disc-shaped recording medium, comprising: an optical pickup, a slide motor, and a spindle motor so as to access arbitrary data on the disc-shaped recording medium. And a waveform shaping circuit that binarizes an analog signal reproduced from the disc-shaped recording medium, and a clock is reproduced from the binarized data output from the waveform shaping circuit to demodulate the data. A signal processing circuit, a buffer RAM for recording digital audio data output from the signal processing circuit or digital audio data input from the outside, and digital audio data once recorded in the buffer RAM are transferred in a predetermined manner. RAM controller for continuous output at speed, and continuous output D / A conversion circuit for converting digital audio data into an analog audio signal and outputting the analog audio signal. Not only audio data reproduced from the disk-shaped recording medium but also digital audio data input from the outside are converted into analog audio signals. A disc reproducing apparatus characterized in that it can be converted into and output. 2. The disc reproducing apparatus according to claim 1, further comprising a mixing circuit capable of adding the voice input from the outside to the voice reproduced from the disc-shaped recording medium and outputting the voice. Disc player.