KR100212086B1 - Demodulation and sync. detecting and inserting and protecting device for digital video disc combined with cd - Google Patents

Abstract

end. The technical field to which the invention described in the claims belongs:

Data reproducing apparatus in CD and digital video disc reproducing apparatus.

I. The technical problem the invention is trying to solve:

Digital Video Versatile (DVD) Disc and Compact Disc (CD) related data can be demodulated, synchronized interpolation, detection, and protection for each mode in the same circuit.

All. The gist of the solution of the invention:

A data reproducing apparatus in a digital video disc reproducing apparatus for a compact disc, comprising: a control unit providing a mode of a current disc for data reading and a control for intact frame synchronization, and a frame synchronization of serial data read from the current disc; A synchronization detecting unit which outputs a synchronous detection signal of the current disk mode when the frame synchronization pattern corresponding to the current disk mode is provided; and frame synchronization according to the frame synchronization period suitable for the current disk mode based on the provided disk mode. And a control unit for synchronizing detection, interpolation and protection by using an interpolator generator for outputting a frame synchronization signal for interpolation in the current disk mode and the frame detection signal for interpolation and interpolation. A control signal generator for outputting to the controller and the current disc mode And a demodulator for demodulating the serial data read from the current disk in a format suitable for the current mode.

la. Important uses of the invention:

DVD

Description

Demodulation, synchronous detection, interpolation, and protection function in CD and DVD player

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data reproducing apparatus for a CD (Compact Disc) and DVDP (Digital Video (or Versatile) Disc Player). The present invention relates to an apparatus for performing mode demodulation, synchronization interpolation, detection, and protection.

The continuous efforts to deliver information that is exploding faster and more accurately ahead of the multimedia era have come to fruition through the recent expansion of digital communication technology, the integration of high density semiconductor (VLSI) and digital signal processing (DSP) technologies. From the beginning, the video, audio, and other data, which have been heterogeneously and independently generated and processed in the past, can be processed and used in a wide variety of forms without discriminating information sources or media. In such an environment, the need for standardization of international transmission standards for digital data has emerged for the smooth transmission and sharing of information between different devices. Accordingly, H.261 of ITU-TS in 1990, JPEG (Joint Picture Expert Group) of ISO / ITU-TS for storage transmission of still pictures in 1992, and Moving Picture Expert Group (MPEG) of ISO / IEC Standardization was done.

As a result, digital data compression technology has also undergone significant advances. Especially, Moving Picture Experts Group (MPEG) 2 has a data rate of less than 10 Mbps and can reproduce the image quality that is currently received at home. In addition, in the audio field, AC-3, an audio compressor method capable of multi-channel audio playback, has been introduced, allowing high-quality audio and multi-sound to be enjoyed at home. It is expected that DVD, which appeared under this background, will play a large part in the role of existing CD-ROM as well as VTR, which is a conventional image recording / reproducing apparatus, with DVD-R (recordable) which will be introduced in the future. Such a DVD is one of the digital moving picture disc media, and is a next generation high-definition and high-quality high-end multimedia storage device that stores a digital video of MPEG2 for two hours or more.

1 is a schematic block diagram of a general DVDP. In FIG. 1, when the disk 10 is rotated, the disk motor 16 starts to rotate at a certain speed. In the optical pickup having the head 12, information reproduced from the disk 10 by the head 12 is converted into an analog high frequency (RF) signal. Is output. This signal is transmitted to the system decoder 18 and the like (as well as the digital phase-locked loop 20) as a data stream EFM shaped as a pulse waveform. The system decoder 18 inputs the data stream EFM, performs demodulation, error correction, descrambling, and outputs the same. The digital phase locked loop 20 is a phase comparator, which is composed of a voltage controlled oscillator and a divider, and generates a first clock synchronized with a signal reproduced from an arbitrary optical disc. The disc drive controller 22 controls the constant linear velocity and other disc related operations of disc rotation in consideration of the frequency servo, the phase servo, and the like according to the frame synchronization signal Sf provided by the sync detector included in the system decoder 18. The microcomputer 24 performs the overall control operation of the DVDP according to the control program. For example, when the microcomputer 24 receives the data transmission start signal from the audio / video decoder 42, 36 or the ROM decoder 32, the microcomputer 24 generates and outputs a transmission control signal. The system clock generator 26 generates a system clock PLCK as a crystal oscillator and outputs the generated system clock PLCK to the driving controller 22 and the system decoder 18.

On the other hand, the first memory 28 connected to the system decoder 18 uses a normal static RAM (SRAM) as the error correction memory, and the second memory 30 uses a dynamic RAM (DRAM) as the memory for the track buffer. The ROM decoder 32 is mainly embedded in a host (eg, a personal computer) and operates according to a command of the host, and transmits data output from the system decoder 18 to the host according to a predetermined interface method. The demultiplexer 34 is a data parser and outputs audio and video signals to the AC3 / MPEG audio decoder 42 and the MPEG2 video decoder 36, respectively. Accordingly, the video data and audio data demodulated by the video decoder 36 and the audio decoder 42, respectively, are transferred to the NTSC (or PAL) encoder 38 and the digital / analog converter 44 and output through the monitor 40 and the speaker 46, respectively.

An example of a widely used disc these days may be a CD. If the DVDP as shown in FIG. 1 is not compatible with the CD, the commerciality of the DVDP will be deteriorated. As a result, products that can be used in both DVDP and CD are being developed. In order to be able to use CDs in DVDP, CD-optic optical pickup is required, and components such as a dual data player for CD and DVD data reproduction will be required. However, in the related art, since the circuit for reproducing the CD data and the circuit for reproducing the DVD data are implemented separately when the combined data reproducing apparatus is implemented, the circuit structure of the combined data reproducing apparatus is complicated and its size is also large.

Accordingly, an object of the present invention is to provide an apparatus for reducing the circuit size and increasing the circuit reliability of a data reproducing apparatus in a DVDP that can also be used with a CD.

Another object of the present invention is to provide an apparatus for performing functions of demodulation, synchronous interpolation, detection, and protection for each mode in the same circuit of a DVD (Digital Versatile Disc) and a CD (Compact Disc).

1 is a schematic block diagram of a typical DVDP

2 is a block diagram according to an embodiment of the present invention

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the same elements in the figures are denoted by the same numerals wherever possible. In addition, detailed descriptions of well-known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

2 illustrates a block configuration for performing demodulation, synchronization detection, interpolation, and protection according to an embodiment of the present invention. The block configuration of FIG. 2 includes a demodulator 60, a synchronization detector 62, an interpolator generator 64, a control signal generator 66, a symbol clock generator 68, a synchronization interpolator 70, and a multiplexer 72, and the system decoder of FIG. It should be understood that it is included in 18. The serial data of the input sources of each block of FIG. 2 means the data stream EFM of FIG. 1, the clock signal means the system clock PLCK generated by the system clock generator 26 of FIG. 1, and the control data is the present invention. According to an embodiment of the present invention, a signal provided by the microcomputer 24 shown in FIG. 1 for distinguishing a mode (CD mode / DVD mode) and controlling synchronization interpolation.

The apparatus for performing demodulation and synchronization detection, interpolation, and protection functions shown in FIG. 2 is implemented on the same circuit, and modes are divided based on control data applied by the microcomputer 24. The data output from each unit generates various signals related to CD or DVD depending on the mode.

In Fig. 2, the synchronization detecting unit 62 detects frame synchronization in the read serial data and the frame of the current mode when the detected frame synchronization matches the frame synchronization pattern of the current mode recognized by the control data (provided by the microcomputer 24). A sync signal, i.e., CD Sync or DVD Sync, is output. The frame synchronization pattern in the CD mode is 24T (T is the system clock period), and the frame synchronization pattern in the DVD mode is 32T. On the other hand, the interpolator generator 64 generates an interpolated frame sync signal, i.e., interpolated CD Sync or interpolated DVD Sync, having a frame sync period suitable for the current mode, based on the control data provided by the microcomputer 24. The frame synchronization period of the CD mode is 588T, and the frame synchronization period of the DVD mode is 1488T. When no synchronization is detected in the synchronization detecting unit 68, an interpolation frame synchronizing signal must be inserted into the portion. The interpolation frame synchronizing signals output from the interpolation synchronizing unit 64 interpolation CD sync and interpolation DVD sync are used at that time. The frame synchronization signals CD Sync, DVD Sync, and interpolation frame synchronization signals Interpolation CD Sync and interpolation DVD Sync output from the synchronization detection unit 62 and the interpolation synchronization generation unit 64 are applied to the control signal generation unit 66.

The control signal generator 66 generates various control signals for the current mode based on the current mode (recognized by the control data) provided by the microcomputer 24. In particular, when the frame synchronization detection is not performed based on the frame synchronization signal and the interpolation frame synchronization signal output from the synchronization detector 68 and the interpolator generator 64, a control signal is generated.

In Fig. 2, the frame synchronization signals CD Sync, DVD Sync and interpolation frame synchronization signals interpolated CD Sync and interpolated DVD Sync outputted from the synchronization detector 62 and the interpolator generator 64 are also applied to the synchronization interpolator 70. The synchronization interpolation unit 70 performs interpolation for the missing synchronization by using the CD frame synchronization signal CD Sync and the CD frame synchronization signal interpolation CD Sync. In addition, interpolation of missed synchronization is performed by using the DVD frame synchronization signal DVD Sync and the DVD frame synchronization signal interpolation DVD Sync. Therefore, the frame synchronization signals CD Sync and DVD Sync output from the synchronization interpolation unit 70 become intact frame synchronization signals without missing synchronization. The frame synchronization signals CD Sync and DVD Sync output from the synchronization interpolation unit 70 are applied to the multiplexer 72. The multiplexer 72 selects and outputs one frame synchronization signal CD Sync or DVD Sync based on the control data of the microcomputer.

Meanwhile, in FIG. 2, the symbol clock generator 68 provides the demodulator 60 with a symbol clock for demodulation based on the current mode provided by the microcomputer 24. The symbol clock in the CD mode is 14T, and the symbol clock in the DVD mode is 16T.

The demodulator 60 converts the serial data input based on the current mode (provided by the control data) provided by the microcomputer 24 based on the symbol clock output from the symbol clock generator 68 to the CD data (7: 0) or DVD data. Demodulate it to (7: 0) and output it. In case of CD, 8 bits of source data are modulated to be 14 bits, and 3 bits of merging bits are provided to have strong characteristics such as noise. Therefore, in case of CD, the unit symbol serial data is composed of 17 bits. In the demodulation unit 60, in the CD mode, 3 bits of a mulching bit are extracted from the serial data, and the remaining bits (14 bits of 17 bits) are clocked by a CD symbol clock (= 17T) to demodulate the data, thereby demonstrating 8-bit data or CD data. Output (7: 0) In the case of a DVD, eight bits of source data are modulated based on eight matching demodulation tables, and 16 bits are composed of unit symbols. Therefore, in case of DVD, unit symbol serial data is composed of 16 bits. In the DVD mode, the demodulator 60 clocks serial data input using a matching table as a DVD symbol clock (= 16T) to demodulate the data and output 8-bit data, that is, CD data (7: 0).

In the above description of the present invention, specific embodiments have been described, but various modifications can be made without departing from the scope of the present invention. Therefore, the scope of the present invention should not be defined by the described embodiments, but should be defined by the equivalents of the claims and the claims.

As described above, in the present invention, since the devices for demodulation, synchronization detection, interpolation, and protection function are implemented on the same circuit, that is, one integrated circuit in each CDP DVDP, not only the circuit size is reduced but also the reliability of the circuit is further increased. There is an advantage to increase. In addition, it is easy to manufacture the set, thereby increasing the product competitiveness.

Claims (3)

A data reproducing apparatus in a digital video disc reproducing apparatus combined with a compact disc, A control unit for providing a mode of the current disc for data reading and providing control for intact frame synchronization; A synchronization detector for outputting a synchronization signal of the current disk mode when the frame synchronization of serial data read from the current disk matches the frame synchronization pattern corresponding to the current disk mode provided; An interpolator generator for outputting a frame synchronous signal for interpolation of the current disc mode according to the present frame mode based on the current frame mode; A control signal generator for outputting various control signals for synchronous detection, interpolation, and protection to the controller by using the synchronization signal of the current disk mode and the interpolation frame synchronization signal; And a demodulation unit configured to demodulate serial data read from the current disk in a format suitable for the current mode based on the provided current disk mode. The demodulation and synchronization detection, interpolation and protection function device according to claim 1, further comprising a symbol clock generation unit providing a symbol clock for demodulation according to the current disk mode to the demodulation unit. The apparatus of claim 1 or 2, wherein the demodulation and synchronization detection, interpolation, and protection function devices are implemented on the same circuit.

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