KR100594200B1 - Optical Disc Playback Method in Spindle Motor Spin-Up Section - Google Patents

Abstract

The present invention relates to an optical disc reproducing method, comprising a look-up table of a range of an appropriate voltage-controlled oscillator in accordance with the position of each disc and the number of revolutions per minute. timer interrupt) In order to execute the routine, the interrupt time interval is set to measure the current disk position value and the current revolutions per minute (RPM) at each interrupt time interval, and then according to the measured current disk position value and the current revolutions per minute. In the spindle motor spin-up section, after the operating range of the voltage-controlled oscillator is read from the look-up table of the memory, the operating range of the voltage-controlled oscillator is set, and then returned to a state before the timer interrupt routine is performed. The present invention relates to an optical disc playback method.

According to the present invention, the optical disk is reproduced in the spin-up section of the spindle motor, so that the response can be made at a high speed even in a physical restraint situation in which the response speed such as the torque of the spindle motor is limited.

Optical disc, revolutions per minute, voltage controlled oscillator, timer interrupt, lookup table

Description

Method for Reading Optical Disk in Spin-up Time of Spindle Motor}             

1 is a flowchart showing a preferred embodiment of an optical disk reproducing method in a spindle motor spin-up section according to the present invention.

The present invention relates to a method for reproducing an optical disc in a spindle motor spin-up section, and more particularly, to an optical disc reproducing apparatus, wherein the range of a voltage control oscillator (VCO) is changed in real time so that a low minute rotation is performed. The present invention relates to an optical disc reproducing method in a spindle motor spin-up section in which data of an optical disc can be reproduced even at a rotation per minute (rpm).

As a recording medium for recording and reproducing information such as video, sound, or data with high density, optical disks, hard disks, cards, or tapes are typical, and among them, the optical disk forms the mainstream. Recently, the optical disk device field has formed a product line that extends from a laser disk (LD) and a compact disk (CD) to a digital versatile disc-read only memory (DVD). Optical discs are usually divided into CDs and DVDs. CDs are divided into CD-ROMs (CD-Read Only Memory) and CD-RWs (CD-Rewritable). DVDs are DVD-ROMs and Random Access Memory (DVD-RAM). Separated by. In addition, the DVD is a DVD-S in which only one information is recorded in a single layer on one track, and a DVD-D in which two pieces of information are simultaneously recorded in a dual layer on one track. Separated by.

In such an optical disc, tracks are formed spirally from the center toward the outside, and record digital data having a predetermined format on the track.

In the optical disc apparatus, light is focused on the optical disc by the focusing control circuit, and guided onto the data track of the optical disc by the tracking control circuit.

The light emitted from the laser diode is focused on the optical disk by the lens and reflected by the reflective surface of the optical disk to the photodetector. From the output signal of the photodetector, data recorded on the optical disc and actual values for the focusing control circuit and the tracking control circuit are obtained. The optical pickup is often moved radially relative to the optical disc by a tracking control circuit, also sometimes called a radial drive, by which light is directed to a spiral data track of the optical disc.

In general, tracking control of an optical disk device is made by a coarse actuator and a fine actuator. The schematic actuator is implemented as a spindle motor, which allows the optical scanning device consisting of a laser diode, a lens, a beam splitter and a photodetector to move in the radial direction. Further, since the light can be inclined by a predetermined small angle in the radial direction by the fine actuator, the light can be moved finely along the radius of the optical disk by this tilting motion.

On the other hand, when the VCO is controlled by the constant angular velocity (CAV), the VCO is not locked until the target RPM is reached. The timing of the lock is based on the torque of the spindle motor. Depends on. The smaller the torque of the spindle motor, the longer the time to reach the target RPM is, the longer the VCO locking time becomes. In order to reduce this long VCO locking time, the VCO is designed to be locked even at a lower RPM than the target RPM, so that the VCO can be locked while the RPM goes up so that data can be read and transmitted even before the target RPM. do.

However, in the conventional case, the VCO once set is fixed without changing the range, so that the motor speed reaches to the target RPM to lock the VCO, which can do nothing during the time required to reach the target RPM. Therefore, there is a problem that unnecessary time loss occurs. As this may be one factor that greatly degrades the user's satisfaction of using the product, such a problem is an issue to be solved in the field of optical disc recording / playing apparatus.

Accordingly, the present invention has been made to solve such a problem, in the optical disk reproducing method, by changing the range of the voltage control oscillator (VCO) in real time in accordance with the RPM (rpm) By reproducing the data of the optical disc even at rpm (rotation per minute), an optical disc reproducing method is provided in the spindle motor spin-up section so that the response can be made at a high speed even in a physically constrained situation where the response speed such as the torque of the spindle motor is limited. Has its purpose.

The optical disk reproducing method in the spindle motor spin-up section according to the present invention for achieving the above objects, the look-up table (look-up) the operating range of the appropriate voltage controlled oscillator according to the position of each disk and the number of revolutions per minute up time) and set the interrupt time interval to perform timer interrupt routine in the memory and measure the current disk position value and current revolutions per minute (RPM) for each interrupt time interval. The timer interrupt routine is set by reading an operating range of the voltage controlled oscillator according to the measured current disk position value and the current revolutions per minute from the look-up table of the memory and setting the operating range of the voltage controlled oscillator. The optical disc can be played in the spin-up section of the spindle motor by returning to the state before Is characteristic.

Hereinafter, a preferred embodiment of an optical disk reproducing method in a spindle motor spin-up section according to the present invention will be described with reference to FIG. 1.

1 is a flowchart showing a preferred embodiment of an optical disk reproducing method in a spindle motor spin-up section according to the present invention.

As a preferred embodiment of the optical disk reproducing method in the spindle motor spin-up period according to the present invention, as shown in FIG.

Step S10 of storing a look-up table of an appropriate voltage controlled oscillator according to the position of each disk and the number of revolutions per minute in a memory;

Setting a predetermined interrupt time interval to perform a timer interrupt routine (S20);

Measuring a current disk position value and a current revolutions per minute (RPM) at each interrupt time interval (S30);

Reading (S40) an operation range of a voltage controlled oscillator according to the measured current disk position value and the current revolutions per minute from a lookup table of the memory; And

After setting the operating range of the voltage controlled oscillator read from the lookup table, the method is configured to perform a step (S50) of returning to a state before performing the timer interrupt routine.

In this case, the interrupt time interval is preferably 50 ms (mile-second).

The operation of the preferred embodiment of the optical disk reproducing method in the spindle motor spin-up section according to the present invention configured as described above will be described in detail with reference to FIG. 1.

First, in step S10, an operating range of an appropriate voltage controlled oscillator according to the position of each disk and the number of revolutions per minute is formed into a look-up table and stored in a memory. This lookup tableization is done offline and stored in memory for real-time processing.

In this way, in the state where the lookup table is created, in step S20, an interrupt time interval is set to 50 ms in order to perform a timer interrupt routine. Thereafter, in step S30, the current disk position value and the current revolutions per minute (RPM) are measured every 50 ms.

In step S40, the operation range of the voltage controlled oscillator according to the measured current disk position value and the current revolutions per minute is read from the lookup table of the memory, and in step S50, the voltage controlled oscillator read from the lookup table. After setting the operating range, the optical disk can be reproduced in the spin up period of the spindle motor by returning to the state before performing the timer interrupt routine.

In other words, the timer interrupt is set to 50ms to measure the current disk position value and the current RPM every 50ms, and based on the measured data, the most suitable VCO range is set for the current position and RPM. In the present invention, the VCO is set to be changeable because there are fixed VCOs in various modes.

This allows the VCO to be dynamically changed according to the current RPM and the current disk position, even at RPMs lower than the target RPM, allowing VCO locking at low RPMs so that data can be read during spin-up time. This has the advantage of enabling data transfer to occur.

Terminologies used herein are terms defined in consideration of functions in the present invention, which may vary according to the intention or customs of those skilled in the art, and the definitions should be made based on the contents throughout the present application. will be.

Although specific embodiments of the invention have been described and illustrated, it will be apparent that the invention may be embodied in various modifications by those skilled in the art.

In addition, since the present invention has been described through the preferred embodiment of the present invention, in view of the technical difficulty aspects of the present invention, those having ordinary skill in the art can easily be different from another embodiment of the present invention. As modifications may be made, it is obvious that both the embodiments and modifications cited in the above description belong to the appended claims.

As described in detail above, in the optical disc reproducing method, a look-up table of an appropriate range of the voltage-controlled oscillator according to the position of each disc and the number of revolutions per minute is stored in a memory. In order to execute timer interrupt routine in the state, set the predetermined interrupt time interval, measure the current disk position value and current revolutions per minute (RPM) at each interrupt time interval, and then measure the current disk position value. Reads the operating range of the voltage controlled oscillator according to the current revolutions per minute from the lookup table of the memory, sets the operating range of the voltage controlled oscillator, and then returns to the state before performing the timer interrupt routine. According to the present invention, by reproducing the optical disk in the spin-up section of the spindle motor, such as torque of the spindle motor In response to physical restraint situations where the answer is the speed limit it is effective to make can be made at high speed.

Claims (2)

Storing a look-up table of the appropriate range of the voltage-controlled oscillator according to the position of each disk and the number of revolutions per minute in a memory; Setting an interrupt time interval to perform a timer interrupt routine; Measuring a current disk position value and a current rotation per minute (RPM) for each interrupt time interval; Reading an operating range of the voltage controlled oscillator according to the measured current disk position value and the current revolutions per minute from a lookup table of the memory; And And setting the operation range of the voltage controlled oscillator read from the lookup table, and then returning to a state before performing the timer interrupt routine. . The method of claim 1, wherein the interrupt time interval, An optical disk reproducing method in a spindle motor spin-up section, characterized in that 50ms (mile-second).

Images