CN1214500A - CD player system with synchronous and anti-vibration functions - Google Patents

Abstract

A CD playing system with vibration-proof function is composed of a data signal processor, a storage and time controller for obtaining the frame being written in the playing data from the storage and time controller when the servo unit finds that the optical pick-up head is in focusing and/or jumping-off tracking state, and a controller for commanding the storage and time controller to discard the frame not being written and for commanding the servo unit to carry out focusing and/tracking again for returning the optical pick-up head to the frame before the frame is written before the focusing and/or jumping-off tracking is lost and for linking data after the pick-up head returns to normal tracking and focusing.

Description

CD player system with synchronous and anti-vibration functions

The present invention relates to a CD playback system with anti-vibration function, and in particular to a CD playback system with anti-vibration capability, which can be connected with the original data stream completely synchronously when the playback data is interrupted for some reason. In order to avoid interruption of CD program playback.

CD (Compact Disc), and various standards derived from the original CD, have become a standard recording medium for multimedia programs including dynamic music and animation images, as well as static mass data storage. As a data storage medium, CD discs have different operational requirements for static file access (file access) such as computer file data, and dynamic program playback (program playback) such as music or movie programs.

Typically, when using a recording medium as a computer data file, the key point required by an optical disc drive for reading a CD is to quickly read data from the disc. In contrast, when used as a recording medium such as a music program, the CD player's requirement for reading the CD disc focuses on the continuous and uninterrupted feeding out of the program data bit stream.

On the other hand, due to factors such as the surface contamination of the CD disc or the vibration of the disc player body, the reading of the disc data may encounter the loss of focusing (focusing) and tracking (tracking) of the data pickup head. escape problem. As far as the static computer file data reading situation is concerned, the interruption of data flow will not cause too much problem, because once the system restores correct focus and/or tracking, the data flow will resume correctly where it was originally interrupted. connect them. The phenomenon of loss of focus and track jump caused by vibration and other conditions, as well as the interruption and delay of data flow, basically has no effect on the purpose of data reading, but the data access time will be longer.

However, in the case of music or video CDs, the phenomenon of loss of focus and track jumping caused by factors such as the vibration of the CD player body has completely different consequences. This is because, if the data bit stream of the music program is interrupted due to the loss of focus or tracking jump of the data reading head, even if the system can stabilize after the vibration phenomenon and restore the correct focus and tracking, it is often impossible. It will cause the interruption of the music playing of the music program. The interruption of this kind of program is really a disturbing trouble for serious music program appreciation. This situation is especially likely to occur in mobile CD systems (mobile CD systems) such as those installed in automobiles. In such mobile applications, where vibration is an unavoidable phenomenon, this interruption of music playback is particularly annoying.

In the prior art, for the interruption of the data flow caused by the loss of focus and tracking jump of the data pickup head, there is a CD player system using a memory buffer to seek to avoid the interruption of the music data flow. This type of system reads a section of data of a certain length before the music data is played immediately, and stores it in a buffer memory. When there is a situation of losing focus or tracking jumping, the system can use the leading and pre-buffered music data stored in the buffer memory to continue the music program while seeking to restore correct focus and tracking based on the current situation data. to avoid interruption of the program.

For example, a basic circuit block diagram of a typical CD playback system is shown in FIG. 1, which shows that the system includes a spin motor (spmdle motor) 20, which can drive the optical disc 10 to rotate at a specified speed, and is driven by an optical pick-up head ( 1aser pickup head) 30 reads the data from the optical disc 10. The data signal picked up by the optical reading head is amplified by the RF amplifier 40, and then sent to the servo circuit 50 on the one hand so as to use a feedback method to adjust and control the rotation motor. 20 rotation speed, and mechanical actions such as focusing and tracking control of the optical pickup head 30 .

On the other hand, the RF signal amplified by the RF amplifier 40 also undergoes necessary processing through the data processor (dataprocessor) 60, such processing includes eight-to-fourteen modulation codes (eight-to-fourteen modulation encoding, EFM ) demodulation, subcode (subcode) acquisition, error detection and correction (error correction and detection, EDC), etc. After these necessary data processing, the music signal can be stored and taken out from the read signal, and finally the obtained digital pure music data is sent to the digital-to-analog converter (D/A) 80, After being converted into an analog music signal, the speaker 100 can be driven by the amplifier 90 to emit sound. In the system of FIG. 1 , the microcontroller 70 is responsible for monitoring and controlling the state of the system, and can receive external instructions to perform selective manipulation actions such as jumping into song selection, etc., during music data access and playback.

In the system of FIG. 1 , the optical pick-up head 30 is part of the mechanical structure, and is easily affected by external mechanical actions. Vibration of the system chassis, etc., may cause the read head 30 to lose focus, or jump off the correct track, resulting in interruption of the music data signal flow between the data processor 60 and the digital-to-analog converter 80 . This phenomenon will cause intermittent music playback, which is more common in car-mounted CD playback systems.

In order to avoid the interruption of playback caused by such vibration, Renyou suggested the system architecture shown in Figure 2. FIG. 2 shows a circuit block diagram of a CD playback system for avoiding playback interruption in the prior art. The main difference between this architecture and the basic system in FIG. 1 in terms of hardware architecture is that it has an additional memory 110 such as random access memory (RAM).

In the architecture of FIG. 2 , after the data processor 60 processes the data output from the RF amplifier 40 , it first stores the processing result in the memory 110 . When the digital-to-analog converter 80 is interrupted due to the loss of correct focus or correct tracking caused by vibration, for example, when the continuous feeding of data is required, the data is read from the memory 110, And sent to the digital to analog converter 80, in order to maintain the continuity of the data, so that it will not be interrupted. Microcontroller 70 uses control servo 50 to adjust the rotational speed of rotation motor 20, so as to accelerate or slow down the speed of taking out data from the optical disc, so that the amount of data stored in memory 110 is kept as full as possible, but will not overflow (overflow) degree.

In the system of Fig. 2, if the CD player causes the optical pick-up head to lose correct focus or even cause track jumping due to factors such as mechanical vibration, at this time, as long as the microcontroller 70 runs out of data in the memory 110 Therefore, the server 50 can be controlled first to continue the data stream interrupted by the vibration, so that the music playback will not be interrupted because the digital-to-analog converter 80 has no data.

However, due to the storage method of data on the disk in the CD standard (IEC 908), how to make the music playback connect to the point where even one byte is not wrong after the mechanical vibration occurs constitutes an important problem. . U.S. Patent No. 5,379,284 to D G. King entitled "Compact disk player having an intermediate memory storage device" ("Compact disk player having an intermediate memory storage device"), which discloses a device that can be read by vibration. When the head loses focus or tracking, the CD player uses the pre-stored data in the register so that the playback of music will not be interrupted. On the other hand, in the U.S. Patent No. 5,148,417 case entitled "Trackingjump compensator for optical disc reproducing apparatus" by A. Wong et al. Compensators for head jumps utilize a similar arrangement to maintain uninterrupted music playback in the event of interruptions in data flow due to loss of focus and/or track jumps such as vibrations. However, neither of these two U.S. patents considered a fully synchronous, perfect connection that is not bad by a single byte.

In I.Kimura et al. entitled "Disk reproducing apparatus and method for reproducing an audio signal and subcode at N times normal speed from a disc" "Disk reproducing apparatus and method for reproducing an audio signal and subcode at N times normal speed from a disk” in U.S. Patent No. 5,615,194, the device disclosed hopes to achieve its so-called one-to-one correspondence (one-to-one correspondence), which is used to achieve synchronous connection of its music, mainly The subcode (subcode) and the data itself of the music data are all stored in the temporary buffer memory, and at the same time, the subcode in the EFM data is always monitored, so that the connection can be carried out immediately when necessary. On the one hand, because the temporary buffer memory also stores subcodes, the storage space is wasted, and on the other hand, the hardware architecture for implementing this method is relatively complicated.

The manner in which the music data is stored on the CD disk is as shown in FIG. 3A. After each synchronization data (SYNC) 200, the subcode (SUBCODE) 210 is immediately followed by music data. The subcode 210 is composed of eight channels from P, Q, R, ... to W, and only 98 subcodes form a complete data frame.

As shown in FIG. 3B, the subcodes in a data frame start with special data S0 and S1. Among the subcodes in the data frame, its Q channel content is as shown in Figure 3C, in which the time (Min:Sec:Frame) and the time (A_MIN:A_SEC: A_FRAME) data. Based on these data, it is possible to achieve a data connection of not less than one byte after the music loses focus or tracks due to vibration.

However, in this type of buffer storage system, the architecture used for music synchronization either cannot achieve complete synchronization with no deviation in every byte, or the system architecture is too complex and the cost is too high. In prior art CD playback systems which employ buffer memory in an attempt to avoid playback interruptions, the joins of the data streams are not perfectly synchronous. In other words, there are systems where the data link is actually a link error of several bytes. This kind of connection still has its shortcomings in the playback of music, and sometimes it will cause abnormal sounds that can be heard by human ears.

Therefore, an object of the present invention is to provide a CD playback system with anti-vibration capability, which can completely synchronously connect with the original data stream when the playback data is interrupted, so as to avoid the interruption of CD program playback.

To achieve the aforementioned object, the present invention provides a CD playback system with synchronous and anti-vibration functions, which includes a control device that can control the actions of the entire CD playback system; a servo device that is connected to the control device and controlled to control the CD. The rotation speed of the CD disc rotation motor of the playback system and the tracking of the optical pickup head; a memory that can store the data in the CD disc; and a data signal processing device with a radio frequency signal input terminal that can accept the optical pickup head from the CD The radio frequency signal read on the optical disc and amplified by a radio frequency amplifier is used for signal processing, and has a playback data output port, which can output the digital playback signal of the processing result to the playback device of the CD playback system, so as to send out the Play sound, wherein the data signal processing device further includes a storage and time control device, when the servo device finds that the optical pick-up head loses focus and/or jumps out of the tracking state, it will notify the control device, and the control device will start from the storage and time control device. The control device acquires the frame of data currently being written to play the frame in the data; on the one hand, the control device instructs the storage and time controller to discard data frames that have not been completely written into the memory, and on the other hand, instructs the servo device to perform optical The focusing and/or tracking action of the read head, so that the optical read head returns to the previous frame of the data frame being written before losing focus and/or jumping off the track, and when the read head resumes After normal tracking and focusing, connect the playback data.

In order to achieve the aforementioned object, the present invention also provides a method for synchronous connection of playing data of a CD playing system with synchronous and anti-vibration functions, wherein the CD playing system includes a control device for controlling the actions of the entire CD playing system; The control device is controlled to control the rotation speed of the CD disc rotation motor of the CD player system and the tracking of the optical pickup head; a memory that can store data in the CD disc; and a data signal processing device, including a memory And the time control device, which also has a radio frequency signal input terminal, which can accept the radio frequency signal read by the optical pickup head from the CD disc and amplified by a radio frequency amplifier for signal processing, and has a playback data output terminal , the digital playback signal of the processing result can be output to the playback device of the CD playback system, so as to emit the playback sound, wherein the steps of the method include: when the servo device finds that the optical pickup head loses focus and/or jumps off the track state, that is, notify the control device; the control device obtains from the storage and time control device that the data frame currently being written is the frame in the playback data; Data frame; the control device commands the servo device to re-focus and/or track the optical pickup head, so that the optical pickup head returns to the data frame that was being written before losing focus and/or jumping off the track On the previous frame; and after the reading head resumes normal tracking and focusing, the playback data is connected.

In order to make the above and other objects, features and advantages of the present invention more comprehensible, preferred embodiments are described in detail below with accompanying drawings.

Brief description of the drawings:

Figure 1 shows a basic circuit block diagram of a typical CD playback system;

Fig. 2 shows the circuit block diagram of a kind of CD playback system that conventional technology avoids playback interruption;

Fig. 3A shows the storage mode of music data in CD disk;

Figure 3B shows the data channel structure of each subcode in a data frame;

Figure 3C shows the content of the Q channel among the subcodes;

Fig. 4 shows the synchronous connection according to the present invention-preferred embodiment, the circuit block diagram of the CD playback system that can withstand vibration;

FIG. 5 shows the circuit in FIG. 4 according to the embodiment of the vibration-resistant synchronous CD playback system of the present invention, and the timing relationship among the relevant signals when the system is in operation.

Detailed Description of the Preferred Embodiment

FIG. 4 shows a circuit block diagram of a vibration-resistant synchro CD playback system according to a preferred embodiment of the present invention. The architecture of the present invention shown in FIG. 4 is basically a server 600, a microcontroller (microcontroller) 400, a memory 500, and a data signal processing represented by a block indicated by reference numeral 300. circuit. Of course, the microcontroller 400 can also be replaced by a microprocessor (microprocessor), depending on the needs.

Of course, this kind of circuit structure must also cooperate with the RF amplifier connected to the signal input line 310 of the data signal processing circuit 300, so as to amplify the data accessed by the optical pickup head on the optical disc driven by the rotary motor. , and connected to the signal output line 440 of the data signal processing circuit 300, the digital-to-analog converter at the back end and the connected amplifier and speaker can play music. Although the embodiment circuit block diagram of Fig. 4 does not show the rotary motor at the front end, the optical pick-up head, the radio frequency amplifier, and the digital-to-analog converter, the amplifier and the speaker at the rear end, but as can be understood by those skilled in the art Or, it should be included in a complete optical disc player playback system.

The data signal processing circuit 300 itself includes an EFM (eight-to-fourteen modulation encoding) demodulator 320, a CIRC (cross-interleave Reed-Solomon code, interleaved Liz-Solomon code) decoder 350, a storage and time control device (RAM & timecontroller 370), an address generator (address generator) 390, an output buffer (outputbuffer) 460, and a series of output (serial output) 430. The EFM demodulator 320 receives the radio frequency data signal transmitted by the radio frequency amplifier shown in the figure, and is directly accessed by the optical head of the system on the optical disc for demodulation. The EFM demodulator 320 is bidirectionally connected with the microcontroller 400 through the lines 330 and 340 to perform its demodulation operation under the control of the microcontroller 400 .

The demodulation output of the EFM demodulator 320 is sent to the back-end CIRC decoder 350 via the line 325, so as to perform the CIRC code decoding operation of the data signal accessed from the optical disc. The CIRC decoder 350 receives the control signal from the microcontroller 400 through the line 340 , and is connected with the storage and time controller 370 through the bidirectional lines 360 and 380 to perform the CIRC code decoding operation.

The decoded output of the CIRC decoder 350 is sent to a memory 500 other than the data signal processing circuit 300 through the line 410 serving as a data bus, and then sent to the output buffer 460 . As will be explained later, the system relies on Data is read from the memory 500 to the output buffer 460 to provide continuous and smooth music data signal output. On the other hand, once the radio frequency data flow is interrupted, the memory 500 still utilizes its stored data to continuously supply data to the output buffer 460 during the period when the mechanism attempts to restore normal focus and/or track, so as to maintain the data Continuous output on output line 440 to avoid interruption of the music signal. Of course, the gist of the present invention is how to keep the data stored in the memory 500 completely coherent and without deviation of a single byte when the mechanical structure of the optical pickup head returns to the correct focus and data track. The correctness of the music data is connected.

The storage and time controller 370 is connected with the microcontroller 400 through lines 382 and 384 so as to direct the decoding operation performed by the CIRC decoder under the control of the microcontroller 400 . On the other hand, the storage and timing controller 370 also controls the action of the output buffer 460 feeding data to the serial output 430 .

The microcontroller 400 monitors and controls the actions of the entire system, and it is connected bidirectionally with the server 600 so that through the server 600, according to what is not shown in FIG. 4 (but shown in FIG. 1 or 2 ) , the feedback control mode of the radio frequency amplifier, and control the mechanical action part of the optical disc drive system, that is, the mechanical action of the optical disc rotation motor and the optical pick-up head.

On the other hand, the microcontroller 400 also controls the entire data signal processing circuit 300, so as to process the radio frequency signal input through the line 310 and read from the optical disc. Its processing system includes the necessary processing such as EFM demodulation and CIRC code decoding in succession, so that the music signal can be converted and restored from its original storage coded format, and the signal output by line 440 can be directly driven by the analog amplifier to produce music. .

During this process, when the optical pickup head loses focus and/or loses tracking due to factors such as vibration, the data signal processing circuit 300 also performs the data connection operation of the present invention. In order to achieve uninterrupted perfect synchronization of data, the microcontroller 400 cooperates with the data signal processing circuit 300 and an external memory 500 to perform its operations. Generally speaking, the operation mode of the system in FIG. 4 is that the radio frequency amplifier (RF AMP, not shown in FIG. 4 ) sends the radio frequency signal RF to the EFM demodulator 320 through the line 310, and is decoded by the EFM demodulator 320. The Q code in the subcode is sent to the microcontroller 400 via the line 330 . When the microcontroller 400 receives the required Q code, it sends an operation signal OPERATION to the EFM demodulator 320 and the CIRC decoder 350 via the line 340 .

When the OPERATION signal on line 340 is not asserted, EFM demodulator 320 does not send data to CIRC decoder 350 . However, once the operation signal OPERATION on the line 340 becomes a logic high level, the EFM demodulator 320 will wait until the next data frame with subcode S0 before starting to transmit data to the CIRC decoder 350 .

Whenever the CIRC decoder 350 decodes the music data, it will notify the storage and time controller 370 on the line 360 with a ready signal READY. Memory and time controller 370 notifies CIRC decoder 350 with read signal READ on line 380 that data has been removed. The storage and timing controller 370 simultaneously controls the address generator 390 to generate an address for the memory 500 to write data into the memory 500 via the data bus 410 .

The storage and time controller 370 notifies the output buffer 460 with a write signal WRITE on the line 420 to read data from the data bus 410 at the same time and at a fixed frequency while the system is playing music. The data of the output buffer 460 is converted into a serial data stream by the serial output (SERIAL OUTPUT) 430, and transmitted to the digital-to-analog converter not shown in FIG. 4 by the line 440, for subsequent amplification and playback use.

When the server 600 receives a signal notifying that vibration has occurred to cause loss of focus and/or track jumping, it notifies the microcontroller 400 via the line 450 . Microcontroller 400 just pulls down the action signal OPERATION on the line 340 to a logic low state, because storage and time controller 370 knows which frame the data frame being written at present is, and microcontroller 400 is controlled by storage and time The device 370 obtains the information of which frame the current data frame is for. On the one hand, the microcontroller 400 instructs the storage and time controller to discard unfinished data frames; to the previous frame of the data frame being written before the vibration. After the read head is reset, the operation signal OPERATION on the line 340 is restarted, so that the music data can be connected.

In the system of the present invention, the storage and time controller 370 does not need to monitor the subcode of the EFM demodulator 320 all the time, but only when discontinuity occurs in the radio frequency signal RF on the line 310, the The controller 400 notifies that the next incoming data is a new start, and notifies the subcode of the new data. Henceforth, the storage and time controller 370 records how much data has been read in by the CIRC decoder 350 by itself. Every time the data of a data frame is read (according to the IEC 908 standard, the music data of a frame has a total of 98×24=2352 bytes), the Q code in the subcode will be increased by one, so that it can be automatically recorded Next, the data of the current CIRC decoder 350 belongs to which frame.

In addition to providing the Q code of the data being written into the memory 500 , the memory and time controller 370 also provides the fullness of the data in the memory 500 to the microcontroller 400 . The microcontroller 400 can make the server 600 control the reading speed of the data read out from the CD disc according to the overflow level data of the memory, so that the data in the storage 500 will not be too empty and rare, but it will not be too much to be full. to leak out.

In Fig. 4, the circuit of the vibration-resistant synchronous CD playing embodiment of the present invention is shown in Fig. 5 as shown in Fig. 5 when the system is in operation. When the ready signal READY on the line 360 of the CIRC decoder 350 becomes logic high, the storage and time controller 370 sends a read signal READ on the line 370 to read data into the memory 500 . At the same time, the storage and time controller 370 also writes a piece of data from the memory 500 to the data buffer 460 with a write signal WRITE on the line 420 at a fixed frequency.

It can be found from the timing diagram of FIG. 5 that when encountering vibration or memory overflow, the microcontroller 400 will pull down the operation number OPERATION to a logic low level, so as to interrupt the EFM demodulator 320 from sending data to The actions of the CIRC decoder 350 and the CIRC decoder 350 are reset. The microcontroller 400 obtains from the time controller 370 that the data currently being stored in the memory 500 belongs to the nth data frame, so it instructs the server 600 to find the position of the n-1th data frame, and starts the action on the line 340 Signal OPERATION. Then the EFM demodulator 320 starts to transmit data to the CIRC decoder 350 when waiting for the next S0 subcode, so that the music can be perfectly connected.

Therefore, it is obvious that the structure of the optical disc playback system of the present invention is resistant to vibration and can achieve a perfect synchronous connection of data streams, and its actual hardware structure is simpler than that of conventional ones, but it can achieve a single byte without error Perfect fit.

Although the present invention has been disclosed above with the description of preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make some modifications and changes without departing from the spirit of the present invention. Therefore, the scope of protection of the present invention shall be defined by the claims of the present invention.

Claims (14)

1. A CD playback system with synchronous and anti-vibration functions, which includes: A control device to control the action of the entire CD playback system; A servo device, connected to the control device and controlled to control the rotation speed of the CD disc rotation motor of the CD playback system and the tracking of the optical pickup head; a memory, which can store the data in the CD disc; and A data signal processing device has a radio frequency signal input terminal, which can accept the radio frequency signal read by the optical pickup head from the CD disc and amplified by a radio frequency amplifier for signal processing, and has a playback data output terminal, The digital playback signal of the processing result can be output to the playback device of the CD playback system so as to emit the playback sound, wherein: The data signal processing device further includes a storage and time control device. When the servo device finds that the optical pickup head loses focus and/or jumps out of the tracking state, it notifies the control device, and the control device obtains the current status from the storage and time control device. The data frame being written is the frame in the playback data; on the one hand, the control device instructs the storage and time controller to discard the data frame that has not been completely written to the memory, and on the other hand, it instructs the servo device to re-start the optical read head. focus and/or tracking action, so that the optical read head returns to the previous frame of the data frame being written before losing focus and/or jumping off the track, and the read head returns to normal tracking After focusing, connect the playback data. 2. The CD playback system as claimed in claim 1, wherein the playback data is music data of a music CD. 3. The CD playing system as claimed in claim 2, wherein the data signal processing device further comprises an EFM demodulator, an interleaved Litz-Solomon code decoder, an address generator, an output buffer and a serial output , when the optical read head loses focus and/or jumps out of the tracking state, or encounters a memory overflow situation, the control device will interrupt the action of the EFM demodulator and reset the interleaved Litz-Solomon code decoder ; The control device obtains the data that is about to be written into the memory from the storage and time controller and belongs to the nth data frame, and orders the server to find the position of the n-1th data frame, and makes the EFM demodulator wait until When the next predetermined subcode of the playback data appears, the data is sent to the interleaved Litz-Solomon code decoder, thus making the playback signals perfectly spliced. 4. The CD playback system as claimed in claim 3, wherein the predetermined subcode is the S0 subcode in the music data format of the music CD. 5. The CD playback system as claimed in claim 1, wherein the control device is a microcontroller. 6. The CD playback system as claimed in claim 1, wherein the control device is a microprocessor. 7. CD playing system as claimed in claim 1, wherein, the broadcasting device of this CD playing system further comprises a digital to analog conversion device, an amplifier and a loudspeaker, wherein this digital to analog conversion device accepts the digital signal of this data signal processing device The broadcast signal output is converted into an analog signal, and sent to the amplifier for amplification, and the sound is emitted by the speaker. 8. A method for synchronous connection of playback data of a CD playback system with synchronous and anti-vibration functions, wherein the CD playback system includes a control device that controls the actions of the entire CD playback system; it is connected to the control device and controlled to control CD playback A servo device for the rotational speed of the CD disc rotation motor of the system and the tracking of the optical pick-up head; a memory for storing data in the CD disc; and a data signal processing device, including a storage and time control device, which also has a The radio frequency signal input terminal can accept the radio frequency signal read by the optical pickup head from the CD disc and amplified by a radio frequency amplifier for signal processing, and has a playback data output terminal, which can digitally display the processing results The signal is output to the broadcasting device of the CD playback system so as to send out the playback sound, wherein the steps of the method include: When the servo device finds that the optical pickup head loses focus and/or escapes the tracking state, it notifies the control device; The control device obtains from the storage and time control device that the data frame currently being written is the frame in the playback data; The control device instructs the storage and time controller to discard unfinished data frames; The control device commands the servo device to re-focus and/or track the optical pickup head, so that the optical pickup head returns to the previous frame of the data frame that was being written before losing focus and/or jumping off the track on; with After the read head returns to normal tracking and focusing, the playback data is connected. 9. The method as claimed in claim 8, wherein the playback data is music data of a music CD. 10. The CD method as claimed in claim 9, wherein the data signal processing device further comprises an EFM demodulator, an interleaved Litz-Solomon code decoder, an address generator, an output buffer and a serial output, When the optical read head loses focus and/or jumps out of the tracking state, or encounters a memory overflow situation, the control device interrupts the action of the EFM demodulator and resets the interleaved Litz-Solomon code decoder; The control device obtains from the storage and time controller that the data that is about to be written into the memory belongs to the nth data frame, and orders the server to find the track position of the n-1th data frame, and makes the EFM demodulator in When the next predetermined sub-code of the playback data appears, the data is sent to the interleaved Litz-Solomon code decoder, so that the playback signals are perfectly connected. 11. The method as claimed in claim 10, wherein the predetermined subcode is an S0 subcode in a music data format of a music CD. 12. The method of claim 8, wherein the control device is a microcontroller. 13. The method of claim 8, wherein the control device is a microprocessor. 14. The method according to claim 8, wherein the broadcasting device of the CD playback system further comprises a digital-to-analog conversion device, an amplifier and a loudspeaker, wherein the digital-to-analog conversion device accepts digital playback from the data signal processing device The signal output is converted into an analog signal, and sent to the amplifier for amplification, and the sound is emitted by the speaker.

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