JPH10340518A - Optical disk reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid the futile consumption of an electric power and a prolong the life of an external device of the other party of data transfer by storing reproduced data once in a buffer memory and changing the reproducing speed of data according to the amount of the stored data. SOLUTION: By adjusting the revolving speed of an optical disk 1 depending upon whether or not a number of data blocks, for storing in a buffer memory 10 for every prescribed time from the start of reading after receiving data transfer instruction from a host computer 200, is larger than a prescribed value, the number of data blocks for storing in the buffer memory 10 is controlled so as to be stabilized near the prescribed value. By stopping the rotation of the optical disk 1 until the buffer memory becomes empty at the point of time when the buffer memory 10 becomes full, futile consumption of the electric power is avoided. By increasing the rotating speed of the optical disk 1 at the point of time when a number of data blocks to be stored in the buffer memory 10 becomes below the lower limit value, a waiting time is not caused.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk reproducing apparatus for reproducing data recorded on an optical disk as an information recording medium, and more particularly, to temporarily store the reproduced data when transferring the reproduced data to the outside. The present invention relates to an optical disk reproducing device.

[0002]

2. Description of the Related Art For example, in an optical disk reproducing apparatus for transferring data reproduced from an optical disk to an external host computer, before transmitting the data to the host computer, a buffer called a decode buffer is used to convert the reproduced data into data blocks of a fixed size. The data is temporarily stored in a memory, and predetermined processing such as error correction (hereinafter referred to as “decoding processing”) is performed on the reproduced data on the buffer memory.
Then, the decoded data block is ready to be transferred to the host computer.

Here, for one data block,
The transfer time to the host computer (the time from the transfer of one data block to the transfer of the next data block) becomes longer after the reading from the optical disk in the optical disk reproducing apparatus is started and the time on the buffer memory. If the time is shorter than the time required for the decoding process to be completed (hereinafter referred to as “time to store data in the buffer memory”), 1
Since the transfer of the previous data block to the host computer is completed before the decode processing of one data block is completed, the transfer to the host computer is started at the same time as the decode processing is completed. It is almost empty (it will not be full because no more data blocks can be stored).

Similarly, when the transfer time to the host computer is equal to the storage time to the buffer memory,
The buffer memory is always almost empty, and if the transfer time to the host computer is shorter than the storage time to the buffer memory, the host computer waits until the decoding process is completed on the optical disk reproducing device side. In other words, there is no waiting time on the host computer.

As described above, when the transfer time to the host computer is shorter than or equal to the storage time in the buffer memory, the transition of the number of data blocks stored in the buffer memory is as shown in FIG. Thus, the buffer memory does not become full, and the optical disk reproducing apparatus can constantly read data.

However, the transfer time of the reproduced data to the host computer is determined by the data processing capacity of the host computer to which the data is transferred. Therefore, the transfer time to the host computer is sometimes longer than the storage time to the buffer memory. is there. In such a case, even if the decoding process for one data block is completed on the optical disk reproducing apparatus side, the transfer of the previous data block to the host computer has not been completed, so the data is stored in the buffer memory. The number of stored data blocks for which decoding processing has been completed gradually increases, and the buffer memory may eventually become full.

When the buffer memory becomes full as described above, the optical disk reproducing apparatus pauses the data reading, and several data blocks are transferred to the host computer to make room in the buffer memory. (The data block can be stored). The transition of the number of data blocks stored in the buffer memory at this time is as shown in FIG. 5, and the optical disk reproducing apparatus transfers data blocks to the host computer while repeating reading and pause. In the conventional optical disk reproducing apparatus, the optical disk is kept rotated even when the data reading is paused.

[0008]

However, the rotation of the optical disk when data reading is in a pause state is an unnecessary rotation, and wasteful power is consumed. In the optical disk reproducing apparatus, since the optical disk is rotated at a high speed in order to realize high-speed reading, particularly when the optical disk reproducing apparatus is driven by a battery, or when the apparatus is driven by a battery, the optical disk reproducing apparatus is mounted. Considering the case, it can be said that the unnecessary rotation is a large negative factor.

Also, since the spindle motor for rotating the optical disk constantly rotates at a prescribed high rotation speed during data reading, the absolute rotation speed of the spindle motor (the rotation speed of the spindle motor associated with one data transfer operation) )
However, there is a problem that the life of the spindle motor and, consequently, the life of the optical disk reproducing apparatus is short.

Therefore, the present invention does not consume power unnecessarily,
It is another object of the present invention to provide an optical disk reproducing apparatus that can achieve a longer life depending on an external device to which data is transferred.

[0011]

In order to achieve the above object, in the optical disk reproducing apparatus of the present invention, when transferring data reproduced from an optical disk as an information recording medium to the outside, the reproduced data is temporarily stored in a buffer memory. In the optical disk reproducing apparatus for storing the data, the data reproducing speed is changed according to the amount of data stored in the buffer memory.

Naturally, if the data reproduction speed is changed, the storage time in the buffer memory will change.
With the above configuration, for example, when the amount of data stored in the buffer memory exceeds a predetermined amount, the data reproduction speed is reduced, and conversely, the amount of data stored in the buffer memory does not exceed the predetermined amount. In such a case, if the data playback speed is appropriately changed according to the amount of data stored in the buffer memory, such as increasing the data playback speed, the data transfer can be performed even if the data playback speed is minimized. Except when the transfer time to the external device is longer than the storage time in the buffer memory at this time, it is possible to prevent the buffer memory from becoming full and to constantly read data. Even when the data reproduction speed is maximized, the data transfer destination external device waits at the data transfer destination external device unless the transfer time to the external device is shorter than the storage time in the buffer memory at this time. The optical disk will not always rotate at the maximum rotation speed unless the amount of transfer data is extremely small. I do.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a main part of a CD-ROM drive device 100 according to an embodiment of the present invention, wherein 1 is an optical disk (CD-ROM), 2 is an optical pickup, 3 is an RF amplifier, 4 is a spindle motor,
5 is a feed motor, 6 is a motor driver, 7 is a servo I
C and 8 are CD-ROM decoders, 9 is a system control microcomputer, and 10 is a buffer memory.

The operation of each section will be described. The optical pickup 2 is a head that irradiates an optical disk 1 as an information recording medium with light and takes in reflected light from the optical disk 1, and an RF signal (modulated and modulated) recorded on the optical disk 1. Data). The RF amplifier 3 amplifies the RF signal read by the optical pickup 2.

The spindle motor 4 is a motor for rotating the optical disk 1. The feed motor 5 is the optical pickup 2
Is a motor for moving the optical disk 1 in the radial direction of the optical disk 1. The motor driver 6 includes a spindle motor 4, a feed motor 5,
An objective lens 2 involved in irradiating light to the optical disc 1 in the optical pickup 2 and injecting reflected light from the optical disc 1
The driver circuits that respectively drive the actuators (not shown) that move a are combined into one.

The servo IC 7 is driven by the motor driver 6 so that the operation of the system control microcomputer 9 such that the light emitted from the optical pickup 2 follows a target track on the optical disk 1 accurately is performed. This is a circuit for performing feedback control of each motor and actuator. The circuit controls power supplied to the motor driver 6 in accordance with a control command from the system control microcomputer 9 and receives an RF signal passed through the RF amplifier 3 to perform light tracking. The following state is given to the system control microcomputer 9.

The CD-ROM decoder 8 is connected to a host computer 200 which is an external device. The host computer 200 receives a command from the host computer 200 and stores data read from the optical disk 1 in a buffer memory 10. Buffer memory 1
0 after decoding on host computer 2
The operation of transferring data to 00 is performed under the control of the system control microcomputer 9.

The system control microcomputer 9 controls the operation of each drive system and the operation of the CD-ROM decoder 8 via the servo IC 7 as described above, and receives a signal from the host computer 200 input to the CD-ROM decoder 8. Of the servo I / O so that the data to be transferred is read out based on the address information of the data to be transferred included in the command.
A control command is sent to C7. Further, the system control microcomputer 9 can know the number of data blocks stored in the buffer memory 10 via the CD-ROM decoder 8.

The buffer memory 10 stores C as described above.
The D-ROM decoder 8 is used to perform decoding processing on the data read from the optical disk 1. However, the D-ROM decoder 8 may be used in the event that the servo is disconnected or the data transfer command from the host computer 200 continues. , Number 1
About 0 data blocks can be stored.

With the above configuration, the CD-ROM drive device 100 reads predetermined data from the optical disk 1 based on an instruction from the host computer 200 and transfers it to the host computer 200. The transferred data is temporarily stored in the buffer memory 10 in order to perform a decoding process.
If the storage time is shorter than or equal to 0, the buffer memory 10 is always almost empty.

On the other hand, when the transfer time to the host computer 200 is longer than the storage time in the buffer memory 10, the number of data blocks stored in the buffer memory gradually increases.
0 becomes a full state where the data block cannot be stored any more, and the data cannot be read.

Therefore, in the CD-ROM drive device 100 of the present embodiment, when reading data in response to a data transfer command from the host computer 200, the system control microcomputer 9 sets the optical disk 1
Changing the rotation speed of the servo IC 7 (the gain of the servo IC 7,
(Including changing the clock frequency or the like involved in the decoding process of the CD-ROM decoder 8), that is, by controlling the data reproduction speed, so that the buffer memory 10 is controlled not to become full. Nevertheless, when the buffer memory 10 becomes full, or when the number of data blocks stored in the buffer memory 10 decreases, it is expected that a waiting time in the host computer 200 of the data transfer destination will occur. If a condition occurs, appropriate measures are taken. Hereinafter, an operation performed by the system control microcomputer 9 when reading data will be described with reference to a flowchart shown in FIG.

First, when data reading is started with the rotation speed of the optical disc 1 maximized, after a timer is started (# 201), it is determined whether or not reading of all data requested to be transferred has been completed. If the reading of all data is completed (Y of # 202), the routine ends, while if the reading of all data is not completed (N of # 202), #
Move to 203.

In step # 203, it is determined whether or not the number of data blocks stored in the buffer memory 10 is the maximum, that is, whether or not the buffer memory 10 is full. (Y in # 203), the data reading is switched to the pause state (# 203).
212), the process returns to # 201. On the other hand, if the number of data blocks is not the maximum (N of # 203), the process proceeds to # 204.

In step # 204, it is determined whether the number of data blocks stored in the buffer memory 10 is equal to or less than the lower limit value.
That is, if the number of data blocks stored in the buffer memory 10 further decreases, it is determined whether or not a state in which a wait time is likely to occur in the transfer destination device is determined. If it is below the lower limit (#
(Y of 204), the process proceeds to # 208 described below, while if the number of data blocks is not less than the lower limit (N of # 204),
Shift to # 205.

In # 205, the count value of the timer started in # 201 becomes T, and it is determined whether or not a predetermined time T has elapsed. If the predetermined time T has not elapsed (N in # 205) , # 202, while the predetermined time T
Has elapsed (Y in # 205), the process proceeds to # 206.

In # 206, it is determined whether or not the number of data blocks stored in the buffer memory 10 is equal to or greater than a predetermined value. If the number is equal to or greater than the predetermined value (Y in # 206), whether or not the apparatus is in a pause state is determined. Is determined (# 207), and if it is in the pause state (Y in # 207), the process returns to # 201. If it is not in the pause state (N in # 207), the rotational speed of the optical disc 1 is reduced (# 207). # 209), and return to # 201.

On the other hand, if the result of determination in # 206 is that the number of data blocks is not equal to or greater than the predetermined value (N in # 206), it is determined whether or not the apparatus is in a pause state (# 208). (Y in # 208), the pause state is released (# 211), and the process returns to # 201. On the other hand, if not in the pause state (N in # 208), the rotation speed of the optical disc 1 is increased (# 210). , And return to # 201.

Here, the pause state in the CD-ROM drive device of the present embodiment differs from the pause state in the prior art in that not only the optical pickup 2 is stopped at a predetermined position with respect to the optical disk 1 but also the optical disk 2 The rotation of the optical disk 1 is stopped to stop the data reading, and the release of the pause state at # 205 means that the optical disk 1 is rotated at the minimum rotation speed and the data reading is resumed. It means to do.

For example, when data can be read out by rotating the optical disc 1 at three different rotation speeds of four times, six times and eight times the rotation speed of a normal music CD, the processing in # 203 is performed. Increasing the rotation speed of the optical disc 1 means changing the rotation speed of the optical disc 1 by one step from 4 times speed to 6 times speed or from 6 times speed to 8 times speed. Decreasing the rotation speed of 1 means that the rotation speed of the optical disc 1 is reduced by one step from 8 × speed to 6 × speed or from 6 × speed to 4 × speed.

When the rotation speed of the optical disk 1 is reduced, if the rotation speed at that time is the minimum, the rotation at the minimum rotation speed is maintained without lowering the rotation speed. If the rotation speed at that time is the maximum when the rotation speed of the first rotation speed is increased, the rotation at the maximum rotation speed is maintained without increasing the rotation speed.

Since the system control microcomputer 9 operates as described above, the data blocks stored in the buffer memory 10 at predetermined time intervals T after the data reading is started in response to the data transfer command from the host computer 200. The rotation speed of the optical disc 1 (that is, the data reproduction speed) depends on whether the number is equal to or more than a predetermined value.
Is adjusted so that the number of data blocks stored in the buffer memory 10 is controlled to be stable around a predetermined value. As a result, when the number of data blocks stored in the buffer memory 10 changes, for example, as shown in FIG. 3, data reading can be continuously performed, and unnecessary power consumption does not occur.

Further, there may be a case where the buffer memory 10 inevitably becomes full due to a balance between the data processing capability of the host computer 200 and the rotational speed of the switchable optical disk 1 in the CD-ROM drive device 100. However, at that time, the buffer memory 10
Becomes full, the rotation of the optical disc 1 is stopped until the buffer memory 10 becomes available (the number of data blocks stored in the buffer memory 10 becomes a predetermined value), so that it is useless. The situation of consuming power is avoided.

When the number of data blocks stored in the buffer memory 10 becomes equal to or less than the lower limit, the rotation speed of the optical disc 1 (that is, the data reproduction speed) increases (when a pause state is set, the pause state is set). (The state is released.) As a result of adjusting the rotation speed of the optical disc 1 depending on whether the number of data blocks stored in the buffer memory 10 is equal to or more than a predetermined value, the data reproduction speed is maximized. In addition, except for the case where the number of data blocks stored in the buffer memory 10 is reduced, the problem that the waiting time occurs in the host computer 200 as the data transfer destination does not occur.

In addition, unless the transfer data amount is extremely small, unless the transfer data amount is extremely small, unless the data reproduction speed is maximized, the number of data blocks stored in the buffer memory 10 decreases. Since the spindle motor 4 does not always rotate at the rotation speed, the absolute number of revolutions of the spindle motor 4 decreases, and the life of the CD-ROM drive becomes longer.

In the optical disk reproducing apparatus according to the present embodiment, the rotation of the optical disk is stopped while the data reading is in the pause state. However, this causes unnecessary power consumption. Even if it is not performed, if the power consumption at the start of rotation of the optical disk is large and there is a possibility that the power consumption will increase in total, the rotation that can be switched during the data reading pause state is possible. The optical disk may be rotated at the minimum rotation speed among the speeds.

In the optical disk reproducing apparatus according to the present embodiment, the rotation speed of the optical disk is switched by increasing or decreasing depending on whether the number of data blocks stored in the buffer memory exceeds a predetermined value. ,
Instead of this, the rotation speed is set in advance for each number of data blocks stored in the buffer memory, and the number of data blocks stored in the buffer memory is checked at predetermined time intervals. The rotation speed may be switched to a preset rotation speed for the number of blocks.

[0038]

As described above, according to the optical disk reproducing apparatus of the present invention, unnecessary power consumption is eliminated.
When the optical disk reproducing device is driven by a battery,
Alternatively, when the optical disc reproducing apparatus is mounted on a battery-driven device, an effect of prolonging the use time can be expected, which is particularly useful. In addition, since the absolute number of rotations of the spindle motor for rotating the optical disk is reduced, the effect of extending the life of the optical disk reproducing device is also expected.

[Brief description of the drawings]

FIG. 1 is a main block diagram of a CD-ROM drive device 100 according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a series of operations performed after a system control microcomputer 9 receives a data transfer command from a host computer 200 and starts reading data.

FIG. 3 is a diagram showing an example of a transition of the number of data blocks stored in a buffer memory 10 in a CD-ROM drive device 100 according to an embodiment of the present invention.

FIG. 4 is a diagram showing a transition of the number of data blocks stored in the buffer memory when transfer time to the host computer ≦ storage time in the buffer memory.

FIG. 5 is a diagram showing a transition of the number of data blocks stored in a buffer memory in a conventional optical disc reproducing device when transfer time to a host computer> storage time in a buffer memory.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical disk (CD-ROM) 2 Optical pickup 2a Objective lens 3 RF amplifier 4 Spindle motor 5 Feed motor 6 Motor driver 7 Servo IC 8 CD-ROM decoder 9 System control microcomputer 100 CD-ROM drive device 200 Host computer

Claims (1)

[Claims] When transferring data reproduced from an optical disc, which is an information recording medium, to an external device, an optical disc reproducing apparatus for temporarily storing the reproduced data in a buffer memory, the data according to the amount of data stored in the buffer memory. An optical disk reproducing apparatus characterized by changing a reproducing speed of an optical disk.