JPS6050750A - Disk record reproducer - Google Patents

Abstract

PURPOSE:To detect easily and quickly the actual linear speed of a disk record for a disk record reproducer of an optical compact disk (CD) type, by using a prescribed address, an expected address, a prescribed linear speed and an arriving address which are all stored to a memory means previously. CONSTITUTION:When a program is started, a microcomputer incorporated to a control circuit 201 searches a prescribed address Tp stored previously to an ROM 214 through a pickup 207, then shifts the pickup 207 up to a position ahead of N tracks via an interface and an external control circuit 203. Thus an arriving address TD where the pickup actually reaches can be read out of an address detecting circuit 211 and stored to an RAM 213 via the interface and the micro- computer. The address Tp, an expected address TT, a prescribed linear speed VT stored previously to the ROM 214 are used together with the address TD stored in the RAM 213 to calculate an equation I . Thus the acutal speed VD of a disk record is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to, for example, a CD (optical compact disc) type disc record reproducing apparatus, and particularly relates to measurement of the linear velocity of a disc.

[Technical background of the invention and its problems]

Recently, in the field of audio equipment, PCM (pulse code modulation) is being used to achieve as high fidelity reproduction as possible.
Digital recording and playback methods using technology are being adopted.

This is called digital audio, and the audio characteristics do not depend on the characteristics of the recording medium, making them significantly superior to those using conventional analog recording and playback methods. This is because it is established in principle.

In this case, a system that uses a disk as a recording medium is called a DAD system, and optical, electrostatic, and mechanical recording and reproducing methods have been proposed. Even when this method is adopted, the playback device that embodies it is still required to be able to satisfy various advanced control functions and performance that are not found in conventional devices.

Well, if we take the CD system as an example,
Diameter 12c++1. C is a disk made by coating a transparent resin disk with a thickness of 1.2 mm with a metal thin film that forms pits (irregularities with different reflectances) corresponding to digital PeM data.
Approximately 500 to 200 r by LV (constant linear velocity) method
, P, and m, and is reproduced in a linear tracking manner from the inner circumferential side to the outer circumferential side using an optical pickup incorporating a semiconductor laser and a photoelectric conversion element. This disc has a track pitch of 1.6 μm, and a huge amount of information is recorded in the program area (radius 25 to 58 mm) in the program area (radius 25 to 58 mm), digitized along with address data, allowing for approximately 1 hour of stereo playback on one side. Table of Contents (TOC) data indicating the start address of each song number is digitized and recorded in the lead-in area (radius 23 to 25 mm).

Disc record playback devices for such discs are equipped with high-speed fast-forward and fast-reverse operations in order to easily and selectively play back the desired data to be played, since the recorded information on the disc is enormous. It is equipped with a sending function and a search function to automatically search for a desired address. Further, some disc record playback devices are provided with a memory function that can store desired information in order to be able to search for the address of the data to be played back in a timely manner, in addition to the search function.

Although the linear velocity of the disc is based on the CLV method, the width (1.2 to 1.4 m/s) is specified in the CD standard specifications, and the disc records currently on the market are recorded at 1.2 m/s. ), which is determined at the time of manufacturing the disc record. If only normal playback is performed, there is no peace of mind knowing the actual linear velocity of the disc record, so it is possible to control the predetermined CLV control by performing servo control using the synchronization signal recorded on the disc record.
Since it is possible to roll, there is no problem with playback. However, when adding special functions to a disc record playback device, it becomes important to know the actual linear velocity of the disc record. For example, a table of playing time versus flat diameter distance of a disk record, which is used when the actual linear velocity obtained by the present invention is used as a reference to accelerate the pull-in of the CLV control system, or when performing a search operation at high speed and with high precision. In addition, when the pickup is moved at high speed, it may be used as a means for accurately displaying the position of the pickup during the movement. On the other hand, various methods have been considered to measure the actual linear velocity of the disk, but it is desirable to have a simple configuration that can quickly measure without using too much memory, which is a relatively expensive component. ing.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a disc record playback device that can easily and quickly detect the actual linear velocity of a disc record.

[Summary of the invention]

The configuration of the present invention will be explained based on FIG.

In response to a signal from the predetermined address (TP) search signal generating means, the pickup locates at the predetermined address (Tp) while performing a search operation. From this position, the pickup is moved N tracks ahead by a signal from the pickup drive signal generating means, and the destination address (TD) of the position actually reached by the pickup is read. A predetermined address (TD) and a scheduled address (TT) stored in advance in the storage means.
), the predetermined linear velocity (VT) and the destination address (TD), and calculate the actual linear velocity (VD) of the transfer station fly record.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a CD type disc record reproducing apparatus to which the present invention is applied will be described with reference to the drawings.

First, the outline of the disc record reproducing apparatus in this embodiment will be explained based on FIGS. 2 and 3.

Fig. 2 shows a front external view of the disc record playback device, and a horizontal loading type disc loading section (111) that can be opened and closed is formed on the left side of the center front of the cabinet (110). .

On the lower right side of this disk loading section (111) is an open/close switch (0PEN/0PEN) for opening and closing the disk loading section.
There is a CLO8E) key (112), and on the left side of the disk loading section (111) there is a power button (POWER) for connecting and disconnecting the power.
) key (113) is provided.

In addition, on the right side of the center front of the cabinet (110) there is a display section (114) for making various displays described later, and further on the right end there is a display section (114) for controlling the play.
) key (115) and pause (PAU) key for pose operation.
8'B) key (116) is provided. The front lower part of the cabinet (110) has 0°1.
2. ..., 9 number keys (117) to (126),
MEMORY key (127), memory read (M-READ) key (128), clear (CL)
EAR) key (129), time (TIME) key (1)
30) , REPEAT key (131)
, reverse (RBV) key (132), fast 7.7-degree (pF) key (133), i y
(DOWN) # - (134), Up (UP) -
? -(135), AUTOPAUS
E) key (136) and stub (5TOP) key (
137) is provided.

In addition, the above-mentioned display section (114) has a data (DATA) display (114a) and a disk (DIS) at its left end.
C) Indicator (114b), stop (STOP) indicator (114'C).

PAUSE indicator (114d), play (
PLAY) display (114e) and memory play (M-
A PLAY) display (114f) is provided, and an autobose (A-PAUSE) display (114f) is provided at the right end.
) - Taltime (T-'I'IME) indicator (11
4h), a remaining time (R-TIME) indicator (1141) and a repeat (REP EAT) indicator (114j). Also, in the center is a 16 channel memory indicator (MEMORY-
INDICATOR) (o4k), song number (MUSICN)
O) Display (1142) and time (TIME) display (
114m), and a pickup position indicator (114n) is provided to the lower left end thereof.

FIG. 3 shows the electric circuit system of the CD type disc record reproducing apparatus shown in FIG. That is, by selectively operating each of the aforementioned keys (112) to (137), the disc playback system (202) is controlled to a predetermined level via a control circuit (201) comprising a microcomputer, an interface circuit, etc. In addition to controlling the state, the display section (114) described above displays the necessary information.

In the figure, a disc playback system (202) is connected to a disc motor (2) via an external control circuit (203) from a control circuit (201).
04) and the pickup feed motor (205) are driven, the data recorded on the disk (206) is reproduced by the pickup (207), and the reproduced signal is sent to the RF signal detection circuit (208). This RF signal detection circuit (208) sends the reproduced signal to the servo circuit (209).
and a signal supplied to the demodulation circuit (210).

Here, the servo circuit (209) is connected to the pickup (207).
) performs focus and tracking servo, and also sends out various signals to perform linear tracking servo to the pickup feed motor (205).

Further, the demodulation circuit (210) separates a synchronization signal for address detection from the reproduced signal, supplies this synchronization signal to the address detector (211) K, and performs EFM demodulation of the reproduced signal from which the synchronization signal has been separated. D/A converter (212)
is supplied to. Here, the address signal detected by the address detector (211) is the control circuit (211) in the case of table of content (Toe) data in the lead-in area.
01) to the RAM (213), and is used to perform the necessary control functions.If it is program area address data (track number, elapsed time, etc.), it is stored in the RAM (213) via the control circuit (201). Provided for making necessary displays. In addition, the reproduced data returned to an analog signal by the D/A converter (212) is subjected to necessary error correction, deinterleap, error correction, etc. processing to drive the speaker (216) to produce sound. It will be offered.

Note that the ROM (214) in the figure is for driving the control circuit (201) with a predetermined program, and the display section (
114) is a control circuit (201) that controls various signals for display.
It is supplied via the display output control circuit (215) and driven to a predetermined state.

Next, each key (1
12) , (115) to (137) and display section (11
The function of 4) will be explained.

Oven/CLOSE (OPEN/CLO8E) key (
112) If this key is operated during playback, the playback state is canceled and the disk motor (204) is stopped via the control circuit (201) and external control circuit (203).

After the laser diode is turned off and the pickup (207) returns to the starting position, the disk loading section (111) is opened. Further, when this key is operated while the disc loading section (111) is open, the disc loading section (111) is closed.

PLAY key (115) > This key is used both when used alone and when reading memory (M-READ).
key (128) or number (θ~9) key (117)
There are cases where the operation is performed subsequent to the operations in (126).

First, when used alone, as a manual play mode, if the state immediately before operating this key is a pause state, which will be described later, the pause state is canceled and the disc motor (204), pickup feed motor (205), and The pickup (207) is activated and enters the play state. However, if the state immediately before operating this key is in the memory play mode, which will be described later, and the play state is turned off, the mode shifts to the manual play mode after the performance of the song is finished.

Furthermore, search (address related to the specified song number from R, AM)
(search based on the TOC data imported into (213)) and move the pickup (207) to the position where the beginning of the song is to be found) If operated during operation, the play state will be entered after the search is completed. It is done like this.

Then, the memory read (lvl-MAD) key (128
) or number (0 to 9) keys (117) to (126), the search operation state is entered, and after the search is completed, the play state is entered.

<Bose (PAtJ8Fi) key (116) > This key is also used when used alone and for memory read (M-REA).
D ) key (12B) or number (θ~9) key (11
There are cases where the operation is performed subsequent to the operations in 7) to (126).

First, when used alone, if the state immediately before operating this key is the play state, the play state is canceled, the pickup feed motor (205) is stopped, and the pause state is entered. Also, if the operation is performed during search operation,
After the search is completed, it enters a pause state.

When used in combination with the memory read (M4EAD) key (128) or the numeric (0-9) keys (117)-(126), a search operation state is entered, and after the search is completed, a pause state is entered.

Number (0-9) keys (117)-(126) > By operating these keys, each key will
) The song number (MUSIC No.) of the data to be played recorded in
) i.e. track number ('I'NO) and one song (
It corresponds to the index number (X) in 1'I"NO) to specify the playback song. Also, it is used in combination with the memory (8iEMORY) key (127) to write numerical key data to the memory channel. It will be done.

<MEMORY key (127) > Number (0 to 9) keys (117) to i' (126) mentioned above or DOWN key (1a4) described later; UP key (135) When this key is pressed after operation, the specified song number is written as data to be stored in the memory channels (1 to 16) of the control circuit (201) and RAM (213) in order from the lowest available channel number. It looks like this.

Press the <Memory Read (M-READ) Key (128)> key several times to move the channel displayed on the memory indicator (114k), and read out the contents of the specified previously written memory channel. Then, by pressing the PLAY key (115),
After performing a search operation and completing the search, the memory play mode is entered and playback is performed sequentially according to the memory channels. Also, when changing the contents of a memory channel, use this key to call up the memory channel you want to change, and use the memory indicator (11) for that channel.
While 4k) is flashing, press the number (θ~9) key (117
) ~ (126) and press MEMORY
Pressing the key (127) changes the contents of the memory channel.

<Clear (CLEA1't) key (129)> Number (0
~9) If you press this key when you have operated keys (117) to (126) by mistake, the data will be canceled and the song number (MU8IC No.) display (114J,) K will display the original song number. Ru. In addition, memory read (M-RE
When this key and AD) key (128) are operated at the same time, a memory all clear operation state is entered.

<Time (TIME) key (130)> Each time this key is operated, the time displayed on the time display (114m) changes from the elapsed time of one song (normal display) to the elapsed time of all songs and the remaining time of all songs. is being done.

<REPEAT key (131)> Turns on repeat (repeated playback) of all songs or all memory channels each time this key is operated.

It is designed to be turned off.

<Reverse (REV) key (132) > While this key is pressed, the pickup feed motor (205)
This causes the pickup (207) to move toward the inner circumferential side in the radial direction of the disk at high speed, thereby performing a quick return operation.

<Fast forward (FF) key (133):
>While this key is pressed, the pickup feed motor (2
05) The pickup (207) is moved toward the outer circumference in the radial direction of the disk at high speed to perform a fast forwarding operation.

< Tau 7 (DOWN) * - (134) > When this key is operated in manual play mode, a search operation is performed using the address of the start part (head) of the currently playing song as the target address, and the search is completed. Afterwards, it will return to the pre-search mode.

Also, when this key is operated in memory play mode, a search operation is performed using the address of the memory play start part corresponding to the memory channel contents (track number) currently being played as the target address, and the search is performed again after the search is completed. Return to previous mode.

Furthermore, if this key is operated during search operation.

Track number (MU8ICNO) in manual play mode
Search purpose 'I'NO displayed on the display (114J-)
A search operation is performed using the address of the start part of the song with the previous TNO as the target address, and if it is in memory play mode, the song currently displayed on the music number (MUSICNO) display (n4p) is searched. In other words, a search operation is performed with respect to the contents of the search target memory channel, with the address of the memory performance start portion corresponding to the previous memory channel contents as the target address.

<UP key (135)) When this key is operated in manual play mode,
A search operation is performed using the address of the start portion of the next song as the target address, and after the search is completed, the mode returns to the mode before the search.

Also, when this key is operated in memory play mode, a search operation is performed using the address of the memory play start part corresponding to the next memory channel contents as the target address, and after the search is completed, the mode returns to the state before the search. .

Furthermore, when this key is operated during the search operation, in contrast to the case of the DOWN key (134) described above,
In manual play mode, a search operation is performed with the address of the start part of the song having the next TNO for the search target TNO as the target address, and in memory play mode, the search operation is performed using the address of the start part of the song that has the next TNO as the target address, and in the memory play mode, the search operation is performed using the next memory channel of the search target memory channel contents. A search operation is performed using the address of the memory performance start portion corresponding to the content as the target address.

, <AUTOPAUSE key (136
) > Turn on auto-pause (automatically enters pause state after playing one song) every time you operate this key.

It is designed to be turned off.

<Stop (STOP) key (137)> When this key is operated, the play state is canceled, and after the first song search is performed, the disc motor (204) is activated.

Pickup feed motor (205) and pickup (
207) is now stopped.

<Data (DATA) indicator (n4a) > Blinks when the pickup (207) is reading TOC data recorded in the lead-in area of the disc, and the TOC
It is designed to light up when all data is read correctly.

<Disc (DISC) display (114b) >Open/close (0PEN/CLO8E) key (112)
) blinks when the disc loading section (111) is opening/closing after being operated. Also, the disc loading section (
The light goes out when the disc loading section (111) is open, and the disc loading section (111) is open.
11) is closed and the disc (206) is loaded.

<Stop (5TOP) indicator (114C)> Lights up when in the stop state.

<Bose (PAUSE) indicator (114d)> Lights up when in the pause state.

<PLAY indicator (114e)> Lights up during play mode.

Memory play (M-PLAY) display (114f)>
It is designed to light up when in memory play mode.

<Autobose (A-PAUSE) indicator (114F)
〉It lights up when the auto pause function is on.

<Total time (T-TIME) indicator (114h)
>When the time (TIME) is displayed (114m), the light is turned on when the time displayed is the elapsed time of all songs.

Remaining time (R-TIME) indicator (114
i) >Time (TIME) The display is designed to light up when the time displayed on the display is the total remaining time of the song.

<Repeat (RFiPEAT) indicator (114j)
>It is designed to light up when the repeat function is on.

<Memory indicator (MBMORYINDICATO)
R) (114k)>16 channels, and the portions corresponding to all written memory channels are lit. Also, in memory play mode, the part corresponding to the memory channel being played flashes. Furthermore, even during a memory write or read operation, the portion corresponding to the memory channel in operation blinks.

<Track number (MtJSICNO) display (114)) and time (TIME) display (h4m) > These are 8 in total.
It consists of a digit number display.

Collectively, they are referred to as the address display section. That is, two digits each from the left represent TNO (rack number), X (index number), MIN (minutes), and 5Ec (seconds). Here, MIN and SEC are the elapsed time of one song (starts from 00 minutes 00 seconds each time the TNO changes), the elapsed time of all songs,
It is designed to display the remaining time of all songs.

Further, when the disc loading section (111) is open, all the lights are off, and in the playback state, all the lights are on to display the address being played.

If you operate the numeric (θ~9) keys (117)~(126) or the memory read (MR, WAD) keys (128), only TNO, X will be displayed and MIN, SE will be displayed.
C goes out. Also, during the search operation, TNO and X blink, and MIN and 8BC go out.

<Pickup position indicator (114n)) Displays the current playing position of the pickup (207) relative to the disk (206). Starting from the left, the part corresponding to the elapsed time of all songs lights up, and the part corresponding to the remaining time of all songs lights up. The lights are set to go out.

Next, the program written in the ROM (214) is shown in a flowchart as shown in FIG.

When the program starts, the micro combinator in the control circuit (201) connects the interface and search function circuit in this control circuit, the external control circuit (203),
Pickup feed motor (205), RF detection circuit (
208), servo circuit (209), demodulation circuit (21)
0).

The address detection circuit (211) detects the ROM (
The predetermined address (TP) stored in 214) is searched by the pickup (207) (in step). The microcomputer is an interface, an external control circuit (
203), the pickup is moved to N tracks ahead (step ■). The amount of movement of the pickup in the radial direction (the number of tracks) can be easily determined, for example, by counting changes in the output signals of the R and F detection circuits. The destination address (TD) actually reached by the pickup becomes readable by the address detection circuit (211) and is stored in the R, AM (213) via the interface and microcomputer (step 2). Predetermined address ('1'P) stored in advance I(, OM (214)), scheduled address (TT)
, predetermined linear velocity (VT), destination address (TD) stored in RAM (213), calculate the following 0 formula,
Calculate the actual linear velocity (VD) of the disc record (step ■).

v-V xTT-TP D 'r TD-TP"'"°°°゛゛°°° ■Here, the 0 equation will be explained.

Generally, the reference position on the disc record (address T1)
The number of tracks N between and an arbitrary position (address To) is expressed by the following equation.

The reference position (address T1) on the disc record is at a position ri from the center of the disc record, and the address (To) is at a position N tracks in the outer circumferential direction from the reed position. Here, the area on the disk record whose radius is from the center of the disk record to the address (To) is S, and the area on the disk record whose radius is from the center to the address (T1) is S11.The area SL is subtracted from the area. Let the area of the part be 82.

5=81+82 π(tpN+r1)2-πri2+vT(To-T1)
tpVT(To-TI) (tpN+ri)2==r, 2+, tpπ From the above, equation 90 is derived.

Here, the current position of the pickup is set as an address (Tp), and this position is set as a reference position (radius r). If the pickup is moved N tracks toward the outer circumference of the disk record from this position, the expected address that will be reached will be calculated using the table described above to become the address (TT). Further, if the position actually reached by the pickup after moving is the address (TD), and the actual linear velocity of this disk record is VD, then the following equation is obtained.

0 type YT (TT -Tp) -VD (TD-Tp)
The relationship of the 0 expression stands out. That is, by calculating the ratio of the playing time when moving a known number of tracks (hereinafter referred to as the margin), the actual linear velocity of the disc record can be easily determined.

As explained above, in the embodiment of the present invention, a microcomputer was used in the control circuit, but it is obvious that each configuration shown in FIG. 1 can be realized using only hardware (without using a microcomputer). It is. Furthermore, when the present invention is realized using a microcomputer, the flowchart is not limited to that shown in FIG. 4, and the microcomputer software is The flowchart can be changed in various ways by simply assembling the following.

〔Effect of the invention〕

The disc record playback device according to the present invention has a simple configuration (if realized by a microcomputer, the fourth
By simply inserting a processing routine based on the flowchart shown in the figure), the actual linear velocity of the disc record can be easily determined. Further, since there is no need to store conversion tables such as tables in the memory, costs can be reduced, and since the flowchart is relatively simple, the actual linear velocity can be quickly determined.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the overall structure of the present invention, FIG. 2 is a front external view showing an embodiment of a disc record playback device according to the present invention, and FIG. 3 is a disc record playback device shown in FIG. FIG. 4 is a block diagram showing the electrical circuit system of the device, and a flowchart showing the operation of an embodiment of the present invention. 201.4...Control circuit 202...Disc playback system 205...Pickup feed motor 207.
...Pickup 209...Servo circuit 211...Address detection circuit 213...
...RAM 214...ROM Agent Patent attorney Kensuke Norichika (and 1 other person) Figure 1 Figure 4 Figure -348-

Claims (1)

[Scope of Claims] A reproduction means for reproducing a disc record in which a plurality of data to be reproduced and their address data are both digitized and recorded using a pickup that reads these data; and a predetermined linear velocity. , a storage means for storing a predetermined address and a scheduled address at a position where the pickup is moved a certain distance from the predetermined address; a search signal generating means for searching and moving the pickup to the predetermined address by the reproducing means; a pickup drive signal generating means for moving a distance; a means for reading a destination address after the pickup has moved a certain distance; the predetermined linear velocity, the predetermined address, and the scheduled address;
A disc record reproducing device comprising linear velocity calculation means for calculating the actual linear velocity of the disc record based on the reached address.