KR0182436B1 - Variable reproducing control apparatus for optical disc reproducing system - Google Patents

Abstract

According to the present invention, the drive clock supplied to the spindle servo system during the sudden change of the master clock according to the variable speed reproducing function in the optical disc reproducing system can optimally follow the change state of the master clock, and also the DSP data processing. A variable speed regeneration control apparatus in an optical disc reproducing system is provided so that the operation can be performed synchronously with the variable speed operation of the spindle motor.

Accordingly, the present invention restores the channel clock through the PLL circuit 10 from the RF signal read from the optical disk D, and generates a master clock from the PLL circuit 16 from the reference clock to the internal buffer 24. Spindle motor 28 for supplying to the other internal / external circuit side, and generates a drive clock by comparing the phase of the channel clock and the master clock in the phase comparator 22 and receives the drive clock to rotate the optical disk (D) An optical disc reproducing system having a DSP (6) for supplying a motor driving section (26) for driving a motor; Acceleration / deceleration signal generation unit 30 for generating an acceleration / deceleration signal that allows the motor driver 26 to quickly follow the variable speed frequency in accordance with variable speed regeneration. The multiplier multiplies the frequency of the channel clock from the first switch unit 32 and the PLL circuit 10 by performing switching switching for supplying the acceleration / deceleration signal from 30 to the motor driving unit 26. A second switch unit 36 for performing switching switching for supplying the multiplication clock multiplied by 4 times to the internal buffer 24 and the internal / external circuit side, and the function setting unit 38. And a microcomputer 40 for controlling the switching switching of the first and second switch units 32 and 36 according to the execution command of the variable speed reproducing function by key input.

Description

Variable speed playback control device in optical disc playback system

1 is a block diagram showing a variable speed reproduction control apparatus of a conventional general optical disc reproduction system.

2 is a block diagram showing a variable speed reproduction control apparatus in the optical disc reproduction system according to the present invention.

* Explanation of symbols for main parts of the drawings

2: Optical pickup 4: RF amplifier

6: DSP 8: Level Slice

10: PLL Circuit (Channel Clock Recovery)

12: crystal oscillator 14: reference clock oscillator

16: PLL Circuit (Variable Frequency Master Clock)

18: LPF 20: VCO

22: phase comparator 24: internal buffer

26: motor drive unit 28: spindle motor

30: acceleration / deceleration signal generator 32: first switch

34: frequency multiplier 36: second switch unit

38: Function setting part 40: Microcomputer

The present invention relates to a variable speed reproduction control apparatus in an optical disc reproducing system, and more particularly, to enable the spindle servo system to optimally follow the frequency of a master clock during variable speed reproduction of an optical disc in an optical disc reproducing system. The present invention relates to a variable speed regeneration control apparatus in an optical disc reproducing system for optimally performing driving of a DSP (Digital Signal Processor) to match the speed of a spindle motor having a variable speed.

Currently, a video disc is adopted as a disc-shaped information recording medium (hereinafter referred to as an optical disc) on which video information and audio information of a moving picture are recorded. The video disc includes, for example, a video flexible program or a movie program for video flexible training. Alternatively, video information and audio information of a language program for acquiring language are recorded by a MPEG (Motion Picture Expert Group) data compression algorithm.

In an optical disc reproducing system for reading and playing a video disc on which video / audio information of such various programs is recorded, the reproduction speed of the image information and the audio information is required according to a user's need, and a video flexible program is installed on the optical disc. In the case of recording, variable speed reproduction for a predetermined selected video song is required.

According to the variable speed reproducing apparatus of the optical disc reproducing system, the recorded image / audio information is read by irradiating laser light onto the recording track of the optical disc D and receiving the reflected light as shown in FIG. An optical pickup (2), an RF amplifier (4) for amplifying an RF signal according to the read image / audio information, and digitally processing the amplified RF signal in the form of a serial data stream, DSP that generates a variable speed drive clock with variable frequency by the variable speed regeneration function by restoring the channel clock from the synchronization signal included in the RF signal and generating the master clock through the reference clock. And a motor driving part 62 driven to receive variable driving speed for the variable speed regeneration function generated by the DSP 6 so that the recording information from the optical disc D is variable speed regeneration. And a spindle motor 28 that variably rotates the optical disc D by driving the unit 26, wherein the DSP 6 is a signal of the RF signal amplified by the FR amplifier 4; The oscillation clock pulses generated from the PLL circuit 10 and the crystal oscillator 12 which restore the channel clock from the synchronization signal of the RF signal sliced with the level slice 8 and the signal level sliced A reference clock oscillator 14 generating a reference clock of 16.9344 MHz through the reference clock generator, and generating a master clock through the generated reference clock, and a low pass filtering operation of a low pass filter (LPF) (18) and a voltage controlled oscillator (VCO). PLL circuit (16; Variable Frequency Master Clock) for generating a master clock having a variable speed frequency for variable speed regeneration function to the internal buffer 24 and other internal circuits or externally through a phase locked loop function through a voltage controlled oscillation operation of And, A phase comparator 22 for supplying the variable speed drive clock to the motor driver 26 by comparing the phase of the channel clock from the PLL circuit 10 and the master clock for the variable speed from the PLL circuit 16. Is done.

In the variable speed reproducing apparatus of the optical disc reproducing system having such a component, the drive motor having the variable speed frequency for variable speed reproducing supplied from the DSP 6 is supplied from the motor driving section 26 to drive the spindle motor 28. By this, the recording information from the optical disc D can be reproduced at variable speed.

By the way, in the variable speed reproducing apparatus of the optical disc reproducing system, when the variable speed regenerating function is performed, the clock frequency for the variable speed can be changed quickly through the circuit driving, while the spindle servo system for supplying the variable speed driving clock is mechanical. Not only is it difficult to change the speed quickly due to the operation, but also when the frequency of the clock pulse changes abruptly through such variable speed reproduction, the data amount of the recording information read and supplied by the optical pickup 2 and the digital by the DSP 6 An imbalance occurs between the amount of data to be processed and exited, resulting in a situation in which the data in the internal buffer 24 is saturated or exhausted, thereby increasing the error occurrence rate.

Accordingly, the present invention has been made in view of the above-described circumstances, and in the optical disc reproducing system, the drive clock supplied to the spindle servo system during the sudden change of the master clock according to the variable speed reproducing function can follow the change state of the master clock optimally. In addition, it is an object of the present invention to provide a variable speed regeneration control apparatus in an optical disc reproducing system in which a data processing operation of a DSP can be performed synchronously with a variable speed operation of a spindle motor.

According to the variable speed reproduction control apparatus in the optical disc reproducing system according to the present invention, the channel clock is restored through the PLL circuit in the RF signal read out from the optical disc, and the master clock is converted into the PLL circuit from the reference clock. Is generated from and supplied to the internal buffer and other internal / external circuits, and generates a driving clock by comparing the phase of the channel clock and the master clock in a phase comparator, and drives the spindle motor that is supplied with the driving clock to rotate the optical disk. An optical disc reproducing system having a DSP for supplying a motor drive unit; An acceleration / deceleration signal generator for generating an acceleration / deceleration signal for quickly following the variable speed frequency in the motor driving unit according to the variable speed regeneration, and an acceleration / deceleration signal from the acceleration / deceleration signal generator in the variable speed regeneration function. A first switch unit performing switching switching for supplying to the motor driving unit, a frequency multiplier multiplying the frequency of the channel clock from the PLL circuit by four times, and multiplying the multiplied multiplication clock by four times with the internal buffer. And a second switch unit for switching switching to supply to an external circuit side, and a microcomputer for controlling switching switching of the first and second switch units according to an execution command of a variable speed regeneration function by a key input of a function setting unit. A variable speed reproduction control apparatus in an optical disc reproduction system is provided.

According to the present invention made as described above, when the variable speed regeneration function is executed in the optical disc reproducing system, the variable speed drive clock from the DSP supplied to the motor drive unit for driving the spindle motor is the spindle servo operation corresponding to the change value of the variable speed frequency. In addition to supplying the acceleration / deceleration signal to follow well, the variable speed clock signal supplied to the internal buffer and internal / external circuit of the DSP is quadrupled the channel clock recovered from the RF signal read from the optical disc. By supplying as a signal, it is possible to perform signal processing of the recording information in the state most closely following the spindle servo operation.

Hereinafter, the present invention configured as described above will be described in detail with reference to the accompanying drawings.

That is, FIG. 2 is a block diagram showing a variable speed playback control apparatus in the optical disc playback system according to the present invention. In the apparatus of the present invention, the same reference numerals as those in FIG. Detailed description will be omitted.

In the same figure, reference numeral 30 denotes an acceleration / deceleration drive control operation in accordance with the variable speed regeneration function of the motor drive unit 26 which is provided in the DSP 6 and drives the spindle motor 28 for rotating the optical disc D. Acceleration / deceleration signal (i.e., drive clock signal for deceleration operation at variable speed start and deceleration operation at variable speed execution) of the spindle motor 28 by the motor drive part 26 by following the change of the variable speed frequency. Indicates an acceleration / deceleration signal generator that generates a signal.

In addition, reference numeral 32 is provided in the DSP 6 to be switched to the phase comparator 22 side during normal playback to phase out the channel clock from the PLL circuit 10 and the phase of the master clock from the PLL circuit 16. The drive clock of the result of the comparison is supplied to the motor driving section 26, and the acceleration / deceleration signal generation section 30 is accelerated / decreased under the switching control of the microcomputer 40 described later according to the variable speed regeneration function. The first switch part is switched to switch so that the deceleration signal is supplied to the motor driving part 26 side.

Reference numeral 34 denotes a frequency multiplier provided in the DSP 6 to multiply the frequency by four times the frequency of the channel clock from the RF signal of the optical disc D restored by the PLL circuit 10. FIG.

Reference numeral 36 is provided in the DSP 6 to supply the master clock from the PLL circuit 16 to the internal buffer 24 and the internal / external circuit side during normal reproduction, and to be described later in accordance with the variable speed reproduction function. Under the switching control of the microcomputer 40, the second switch unit is switched so that the multiplication clock multiplied by four times the channel clock from the frequency multiplier 34 is supplied to the internal buffer 24 and the internal / external circuit side. Indicates.

Further, reference numeral 38 denotes a function setting unit for inputting an execution command for the overall functional operation of the system by consisting of a remote control unit for remote control of the optical disc reproducing system or a matrix button unit provided in a predetermined portion of the control panel of the main body. A command for executing the variable speed playback function for the recording information in D) is keyed.

Reference numeral 40 denotes a microcomputer which is in charge of controlling the overall functional operation of the optical disc reproducing system. The reference numeral 40 denotes the first and second switch units 32, by the variable speed reproducing function according to the function command of the function setting unit 38. 36) is controlled to switch switching for variable speed reproduction.

Next, the operation of the present invention made as described above will be described in detail with reference to FIG.

First, when the recording information recorded on the optical disc D by the normal reproducing function is read by the optical pickup 2 and amplified through the RF amplifier 4, the amplified RF signal is level sliced by the DSP 6. The signal level is sliced by (8) to restore the channel clock by the PLL circuit 10, while the PLL circuit 16 generates the master clock through the reference clock generated by the reference clock oscillator 14, The channel clock from the PLL circuit 10 and the master clock from the PLL circuit 16 are compared in phase through the phase comparison unit 22 to the motor driving unit 26 through the first switch unit 32. The master clock from the PLL circuit 16 is supplied to the internal buffer 24 and the internal / external circuit side through the second switch unit 36.

In this state, when the function setting section 38 is keyed in for the variable speed function for the optical disc D, the microcomputer 40 has the first and second switch sections 32 and 36 connected to the variable speed function. While switching to switch for supply of the clock pulse according to the acceleration / deceleration signal generating section 30 is accelerated / decelerated signal is supplied to the motor driving unit 26 through the first switch unit 32 and The multiplier clock from the frequency multiplier 34 multiplying the frequency of the channel clock restored from the RF signal from the PLL circuit 10 by the second switch unit 36 via the internal buffer 24. ) And internal / external circuit side.

Accordingly, the motor driving unit 26 is able to rotate the optical disc D by rotating the spindle motor 28 in accordance with the change of the frequency according to the variable speed function, and the DSP 6. The internal buffer 24 and the internal circuit stage and the external circuit stage side perform signal processing synchronously with the operation of the spindle of the variable speed regeneration function by the motor driving section 26 so as to perform data processing of the internal buffer 24. The occurrence of saturation or exhaustion is prevented, and mutually matched operation is possible.

According to the present invention as described above, when the variable speed regeneration function is executed in the optical disc reproducing system, the drive clock supplied to the spindle servo meter is supplied as a clock signal capable of following the clock frequency which changes according to the variable speed. As the clock pulses supplied to the internal buffer and the internal / external circuit of the circuit are supplied as a clock multiplied by four times the frequency of the channel clock of the RF signal read from the optical disk so that the clock pulse can be well followed by the variable speed of the spindle servo system. There is an advantage that the variable speed reproduction function can be improved.

Claims (1)

In the RF signal read from the optical disc D, the channel clock is restored through the PLL circuit 10, and the master clock is generated from the PLL circuit 16 from the reference clock so that the internal buffer 24 and other internal / external circuits are generated. A motor driving unit for supplying to the side and comparing the phase of the channel clock with the phase of the master clock in the phase comparator 22 to generate a driving clock and driving the spindle motor 28 to receive the driving clock and rotate the optical disc D. 26. An optical disc reproducing system having a DSP (6) for supplying an acceleration / deceleration signal for generating an acceleration / deceleration signal that allows the motor driver (26) to quickly follow a variable speed frequency in accordance with variable speed reproduction. The first switch unit 32 performs switching switching for supplying the acceleration / deceleration signal from the acceleration / deceleration signal generator 30 to the motor driving unit 26 during the variable speed regeneration function. Wow A frequency multiplier 34 multiplying the frequency of the channel clock from the PLL circuit 10 by four times, and switching switching for supplying the multiplication multiplier by four times to the inner buffer 24 and the internal / external circuit side. A microcomputer that controls switching of the first and second switch units 32 and 36 according to the second switch unit 36 to be executed and the execution command of the variable speed regeneration function by the key input of the function setting unit 38. And a 40, and performs signal processing in synchronism with the spindle servo operation of the variable speed regeneration function by the motor driving section 26.