JPH0812751B2 - Record carrier reproducing device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reproducing device for a record carrier such as a compact disc player.

[0002]

2. Description of the Related Art A compact disc player has a diameter of 12c.
It is a player that reproduces the audio signal recorded in PCM format on a small disk (compact disk) with a thickness of m and a thickness of 1.2 mm. High fidelity reproduction is possible in combination with the recording format of the audio signal on the disk. However, its feature is not limited to high fidelity reproduction, but has the feature that abundant functions such as the beginning of any song and repeat performance can be performed speedily.

The above-mentioned various functions are performed by using control and display signals recorded on the disc. The information recorded as control and display signals has a start track number, end track number, performance time, and start time of each track in the inner circumference of the disc called a lead-in area, while a program in which audio information is recorded. Area number (song number), index (small section within song),
There is elapsed time in the song and cumulative elapsed time. In this specification, these eight pieces of information will be referred to as "music number, time information".

By the way, the basic functions necessary for carrying out the special reproduction function such as arbitrary cueing and repeat performance, which are performed in the conventional compact disc player (hereinafter referred to as "player"), are (i) control. , A function of reading a display signal and (ii) a function of searching for a target position, and the special reproduction function is achieved by performing these two basic functions in combination with an advanced control means such as a CPU. . Therefore, the operation of the conventional player will be described below focusing on the above two basic functions.

[0005] In FIG. 7, reference numeral 1 denotes a disk, which is given a rotational force by a spindle motor 2. An optical pickup 3 has optical reading means, focus and tracking adjusting means, and the like. A preamplifier 4 waveform-shapes the read data from the disk 1 and also generates a focus error signal and a tracking error signal. A clock recovery circuit 5 generates a clock for demodulating read data.

A demodulator 6 has an EFM (Eight-Four).
teen Modulation) The read data that has been modulated is demodulated into 8-bit data, and the subcode signal included in the read data is extracted. Decoder 7 performs error correction, error correction, decoding of correction code including deinterleaving, and jitter absorption operation. A D / A converter 8 converts the PCM signal input from the decoder 7 into an analog voice signal. A focus servo circuit 9 controls the focus of the signal reading light beam by a focus error signal obtained from the preamplifier 4.

A tracking servo circuit 10 controls the radial movement of the signal reading light beam with respect to the disk 1 in accordance with a tracking error signal obtained from the preamplifier 4. Reference numeral 11 denotes a slider servo circuit, which covers the movement of the disk 1 in the radial direction, which cannot be followed only by the optical pickup 3, by controlling the slider drive unit 12.

Reference numeral 13 denotes a spindle motor servo circuit, which rotates the disk 1 at a constant linear velocity (CLV: Constand).
The rotation of the spindle motor 2 is controlled so that the linear velocity is obtained. Reference numeral 14 denotes a system controller, which has a role of monitoring the state of each unit of the player including the operation input unit 15 and issuing a command to each unit of the player including the display unit 16 to perform various operations.

Here, the basic function of extracting the above-mentioned control and display signals from the disk read data will be described in detail. FIG. 8 shows a disc read signal with a repetition frequency of 7.35 kHz.
The format of a unit called a frame appears in 24 channels bits (channel bits are information units related to disc recording signals) sync signal (a), 14 channel bits control, display signal (b), 336 channel bits. Data (c), error correction bit (d) of 112 channel bits, connection of 102 channel bits, low frequency suppression bit (e) of 588 channel bits in total, and appear in a fixed array.

The 14 channel bits of the control and display signals have an information amount of 8 data bits when converted into a data bit which is an information unit before EFM modulation. Further, the control and display signals are 98 frames, that is, one block (subcoding block) that is repeated at 75 Hz (7.35 kHz / 98 = 75 Hz).
The recorded contents are updated in units of. The sub-coding block includes a sub-coding synchronization pattern for two frames and eight types of information, and one type of information is:
One bit is assigned to a certain digit in one frame. The song number and time information are also included in this one digit. These eight types of information include, in addition to the music number and time information, information indicating the presence / absence of pre-emphasis, information indicating whether it is between songs or within a song. The bit including the music number and time information is called a channel Q and may be used for recording other information, and is distinguished by an identification signal included in the same channel Q.

FIG. 9 shows a recording format when the channel Q indicates the music number and time information in the program area. The mode control signal in the figure is formed of information indicating the presence or absence of pre-emphasis and information indicating whether or not there are two stereo channels. ADR1 is information for distinguishing what the data after ADR represents. In the lead-in area of the disc, information about the start time (cumulative elapsed time) of each song, the first song number of the program, the last song number of the program, and the total playing time, which are distinguished by flags called points, is repeated three times. ing.

To extract the music number and time information, first, the disk read signal is bit-synchronized by the clock obtained from the clock reproduction circuit 5 in FIG. 7, and the demodulator 6 detects the frame synchronization signal and the sub-coding synchronization pattern. The sub-code is separated and extracted from the EFM demodulated data by this synchronizing signal. The system controller 14 inputs the entire 8-bit sub-code or specific bits for the sub-coding block as needed, detects a code error, and inputs a new sub-code if there is an error.
The identification signal confirms that the bit string corresponding to the channel Q is the music number and time information, and finishes the input of the music number and time information.

FIG. 10 is a flow chart of time reading focusing on the operation of the system controller. The data rearrangement of (6) in FIG. 4 indicates an operation of rearranging 96-bit (98-2) serial data for each content so that it can be easily processed by the CPU. The second basic function indispensable for realizing special reproduction such as an arbitrary cueing function is a function of searching for a target position as described above, and it is also important that this is performed quickly. is there. In order to search for a target position designated in the format of music number and time information, a means for moving the trace position of the optical pickup 3 and a means for determining the moving amount are required.

To move the trace position, there is a method of tracing to a target position without traversing a spiral signal track and a method of jumping and moving the track. Since it takes the same time as reproduction, it is used in combination with the latter.
The jump operation is performed by applying a pulse (referred to as a jump pulse) to the tracking servo circuit 10 and forcibly moving the trace position of the optical pickup 3. Reverse polarity pulse (referred to as brake pulse)
Are combined.

Forward jump (disk outer peripheral direction jump) command or reverse jump (disk inner peripheral direction jump) output from the system controller 14
Track jumps are executed by the number of instructions. However, the movable amount of the trace position in the radial direction in the optical pickup 3 is limited, and this is automatically compensated for by the slider servo circuit 11 and the slider drive unit 12.

Next, the movement amount to the target position is determined.
The distance between the current position and the target position given as time information is roughly calculated by the system controller 14, a jump command is output based on the result, and the music number and time information is read at the next position to reach the target position again. The method of calculating the distance and outputting the jump command is repeated. If it is very close to the target position, it traces without jumping and waits for reaching the target position.

System search for target position search operation
FIG. 11 shows the processing of FIG. 14 as the center. Here, the processing of (1) and (2) is performed so that the sound at the beginning of the music is not cut off at the beginning of the music. Is set one second before the start of the music, and the target position is converted to an accumulated elapsed time expression (referred to as an absolute time in FIG. 11).
In FIG. 11, t _A2 is the absolute time at the current position, and t _B0
Is the absolute start time of the target song, t _B1 is the in-track time at the target position, t _B2 is the absolute time at the target position, and N ₁ <N ₂ <N ₃ <N ₄ , T ₁ <T ₂ <T ₃ <
It is assumed that T ₄ <T ₅ <T ₆ <T ₇ .

The lead-in data is read in advance and stored as the start time of the target song (not shown). The PLL lock detection in (3) is a process for confirming that the CLV control follows the movement of the trace position, (4) is the time reading process shown in FIG. 10, and (6) and (7) determine the moving direction. This result is given to the graph P indicating the polarity of the jump pulse, and (8) to (11) are processes for determining the number of jump pulses from the time difference | ΔT | between the current position and the target position. (6) and (8) is equal to the target position is the current position, the immediate vicinity, i.e. T _2> of determining the search end and (10) | [Delta] T | is determined if would jump over the target location to jump Then, (13) is a process for outputting the determined jump pulse number N and direction P. (9)
Steps (14) and (14) relate to voice muting, and when the search start position and the target position are the same or very close, neither jumping nor muting is performed.

By combining the control signal reading function and the target position searching function described above with the system controller 14, a special reproducing operation is realized. For example, in the function of playing songs arranged in order on the disc in an arbitrary order (hereinafter referred to as a program performance), the performance order is input by the operation input unit 15 according to a predetermined method, and the system controller 14 causes these programs to play. Information is stored in a storage circuit (not shown). Next, the system controller 14 repeats the operation of executing the above-mentioned target position search (here, cueing) to start reproduction, and fetching the information of the next song from the memory circuit each time one song ends. Therefore, the program performance can be realized.

As described above, the compact disc player realizes abundant and speedy functions by using the subcodes recorded on the disc, that is, the control and display signals, and in this respect, the cassette tape which cannot be randomly accessed. Have an advantage over.

[0021]

However, in the cassette tape or open reel tape player,
Even if the power is turned on again because the tape winding state preserves the past playback end position, or if the tape is taken out of the player and attached to the player again,
While having the advantage of not listening to the same performance content or having to perform any special operations, conventional compact disc players once turn off the power or execute the disc loading / unloading operation. The information on the disc that has been played back before that is volatilized, and it is necessary to play back from the first song on the disc again or to perform the cueing operation. At this time, if the operator does not remember how many songs have been played before, it is necessary to listen to the contents of some songs in a sampling manner in order to search for that position. It takes time and effort.

If the user removes the disc from the player in order to check the title of the music by looking at the title portion described on the disc surface, the same result as described above will be obtained. Such a problem of the conventional compact disk player becomes more remarkable in a compact disk player for a vehicle. In other words, the in-vehicle player uses the DC power supply of the car, but in most cars, the power supply to the parts other than the engine is stopped when the engine is started. Considering that the user is disconnected and uses the car for a very short period of time almost every day and listens to music at that time, the operability of the conventional compact disc player is extremely poor. In particular, there is a problem that if the operation of the player takes time and trouble for the driver, it is not preferable in terms of driving safety.

The present invention has been made in view of the above conventional problems, and an object of the present invention is to enable a reproduction operation restarted after interruption of power supply to be performed subsequently to the reproduction before interruption. To do.

[0024]

SUMMARY OF THE INVENTION A reproducing apparatus for a record carrier according to the present invention comprises a storage means for storing data relating to a recording carrier reproduction progress step, a special reproduction method progress step, and a reproduction operation mode, and restarting after reproduction interruption. The reproducing operation is determined based on the data stored in the storage means.

[0025]

In the reproducing apparatus for a record carrier according to the present invention, the data of the reproduction progress stage, the special reproduction method progress stage, and the reproduction operation mode when the power supply is interrupted are stored in the storage means and stored in the storage means. The deciding means acts so as to decide the reproducing operation based on the present data.

[0026]

EXAMPLES Example 1. FIG. 1 is a schematic block diagram of a first embodiment of the present invention, and the same reference numerals as those in FIG. 6 denote the same parts. In FIG. 1, reference numeral 17 is a battery, and semiconductor memory 18
Backup. Reference numeral 19 denotes a diode, which constitutes an OR circuit for ORing the DC power supply 20 generated from a power supply supplied through a power switch (not shown) and the battery 17. Reference numeral 21 denotes a power drop detection circuit, which plays a role of completely saving data. By incorporating the battery 17, the semiconductor memory 18 (volatile) can be equivalently used as a nonvolatile memory.

Although the data may be saved in the semiconductor memory 18 only when the output of the DC power supply 20 is reduced due to power-off or the like, in this embodiment, even when the original power is supplied to the player, The semiconductor memory 18 is used as a data storage register, so that a data saving operation is not required. However, since there is a risk that the system controller 14 configured by a CPU or the like may make an erroneous access to the semiconductor memory 18 due to the decrease in the DC power supply 20, the power supply decrease detection circuit 21 may access the semiconductor memory 18 by hardware. At the same time as prohibiting, prevent power consumption due to current outflow to other than the memory circuit.

A non-volatile semiconductor memory may be used as the semiconductor memory 18, in which case there is an advantage that a backup battery is unnecessary. On the other hand, rechargeable batteries or large-capacity capacitors
Alternatively, the configuration may be such that the conduction state is always established without the intervention of a power switch or the like. Further, the semiconductor memory 18 may be backed up not only by backing up but also by including the CPU portion of the system controller 14 or other circuits.

The data to be stored in the semiconductor memory 18 differs depending on the selection of the function to be continuously performed after the power is turned on again. Considering the "sequential play" function and the function that continues special playback methods such as the program performance that was previously input (described above), the minimum required data is the position that was previously played. The time information shown below (hereinafter referred to as "last time information"), information about the playback mode such as the program playing procedure (hereinafter referred to as "program information"), and the order in which the songs were played during program playing Information on the progress stage of the trick play method shown (called a "pointer") is required.

Of these, it is not known when the power is cut off for the last stroke and the pointer, so it is necessary to frequently read the latest information from the disk and transfer it to the semiconductor memory 18, and the system controller 14 performs this function. Be configured to perform.

When the power is turned off, the last time information and the program information are stored by hardware means, so that the system controller 14 does not perform any processing different from the case of FIG. Performs special processing.

FIG. 2 is a flowchart of a sequential play operation centering on the operation of the system controller 14. Where t _min is the absolute start time of the first song, t
_max is the total playing time, Ap is a pointer, [Ai] is the contents of the register Ai, and [[Ap]] is the contents of the address indicated by the pointer.

It is assumed that the initialization of the system controller 14 and the initialization operation of each part of the player have been completed before this flowchart, and the processing for display is omitted in the flowchart. FIG. 3 shows a last time storage register A ₀ , provided in the semiconductor memory 18.
Shows the configuration of a storage register A ₁ to A _N and pointer storage register Ap program information, program play is the order of playing music indicated by A ₂ to the next song indicated by A _1.

The last time and the program information store the music number and the absolute time (accumulated elapsed time), respectively. The absolute time in the program information means the start absolute time of each music. Program performance is A _{1 to} A _{N for the} pointer
Or at the stage of the address of the throat is stored in address A ₁ to A _N, the pointer and the last time if the contents of 0 (reset), indicating that all the program play is completed earlier. If the program performance is not specified, it means that the performance of the entire disc has been completed before.

In FIG. 2, (3) to (6) are registers A.
Sequential play is not performed when the contents of _{0 to} A _N are checked and A ₀ is reset or when the contents of A ₀ indicate the lead-in or lead-out position. The content of A ₀ , that is, the position of the last time is searched in (7) and playback is started, and the latest song number and time are detected in (9) and (10) until the end of the current song is detected in (11). Read information and store in A ₀ . When the end of the song is detected, it is judged in (12) whether or not it is a program performance. If it is a program performance, the content (address) of the pointer is incremented by 1 in (15), and the song to be played next in (16). The process is terminated by judging the presence or absence of "," or the process proceeds to search for the next song.

On the other hand, if it is not a program performance, (1
In 3) it is judged whether or not it is the last song of the disc, and if it is the last song, the performance ends, and if it is not the last song (8)
Return to and perform the next song. (14) is the end of all procedure when playing a program, and when not playing a program,
This is a process for saving the end of the performance of the last song on the disc by resetting A ₀ . The processes of (7) “search” and (9) “time reading” in FIG. 2 correspond to FIGS. 11 and 10, respectively.

The sequential play operation has been described above. As described above, the operability is improved by automatically executing the sequential play.
Since this operation is not always required, countermeasures will be shown in the following embodiments.

Example 2. It is convenient to provide a sequential play operation execution / non-execution operation input means so that a specific initial state or initial operation can be performed without performing sequential play when the power is turned on again.
As a second embodiment in which sequential play can be selectively realized by such means, (i) a mechanically lockable sequential play execution / non-execution switch is provided, and when this switch is non-execution The system controller 14 is provided with a function of resetting the last time register A ₀ in the above embodiment or ignoring the contents of A ₀ . (Ii) An unlock type sequential play execution / non-execution switch and a sequential play execution / non-execution instruction register are further provided in the semiconductor memory 18, and when this switch is pressed, the contents of this register are logically inverted. Then, there is a method of adding to the system controller 14 a process for determining execution / non-execution of the sequential play operation according to the contents of the memory. The former mechanically stores the sequential play execution / non-execution instruction mechanically (the flowchart is omitted).

Example 3. Next, as a third embodiment, sequential play is performed only for a short-time power-off,
A function of performing an initialized operation without performing a sequential play when the power is turned on again after a long power-off will be described below. This is a function for the in-vehicle player to perform the sequential play only when the power is turned off when the engine is started or when the vehicle is stopped for a short time. FIG. 4 is a block circuit diagram showing an essential part of the third embodiment having such a function, which is the same as that of FIG.

In FIG. 4, reference numeral 21 denotes a resistor through which power is supplied to the semiconductor memory 18. Reference numeral 22 is a diode for backflow prevention, 23 is a large-capacity capacitor for a short-time backup power supply, 24 is a comparator, and when the power supply voltage of the semiconductor memory 18 is higher than the reference voltage of 25, High level (shown as "H"), low level (shown as "L") in the opposite case
Output to 14.

When the power supply to the player is normal and the output of the DC power supply 20 is normal, current is supplied to the semiconductor memory 18 through the resistor 21 and the diode 22, but the power supply to the player is stopped or the power supply voltage is reduced. When dropped, diode 22
By the action of, the DC power supply 20 and the memory circuit are separated. In this case, the power supply voltage of the semiconductor memory 18 gradually decreases due to the charging capacity of the capacitor 23, but the semiconductor memory 18 retains its contents even if the power supply drops to a certain extent. The comparator 24 detects a decrease in the power supply voltage of the semiconductor memory 18 as a reference voltage.
By performing the operation as a timer by comparing with 25, the reference voltage 25 is selected to be equal to or higher than the content retention limit voltage of the semiconductor memory 18, thereby compensating for the retention of the content of the memory. In this case, the timer (in other words, the time detecting means) may be configured by a digital detecting means such as a frequency count, without being limited to the illustrated embodiment.

System Controller in Third Embodiment
FIG. 5 is a flow chart showing the process of FIG. 14, and immediately after the initialization at the time of turning on the power again, the comparator 24 is executed at (1).
Output is detected and if it is "H", sequential play is performed, while if it is "L", it is considered that the power supply stop has exceeded a certain time, and all registers A _{0 to} A _N in FIG.
And Ap are reset and the initialized player operation is performed (when A ₀ is reset, sequential play is not performed as described above). The charging speed of the capacitor 23 by the resistor 21 after the power is turned on again is selected to be slow, and when the system controller 14 checks the output of the comparator 24, the voltage of the capacitor 23 is almost the same as the value immediately before the power is turned on again. I try not to.

Example 4. Next, FIG. 6 shows a flow chart of the fourth embodiment, in which a sequential play execution command is not given when the power is turned on again, so that the performance operation is initialized once (for example, the first music piece is sequentially played). If it is within a certain period of time, the function of accepting and executing the sequential play execution command input during that period is provided. Such a function is effective as a function for compensating the carelessness of the operator or a change in intention. Here, it is assumed that the player shown in FIG. 1 is provided with a sequential play switch of a mechanical lock type switch for inputting execution / non-execution of the sequential play described in the second embodiment.

FIG. 6 shows the processing of the system controller for realizing the above functions, which is a modification of the processing of FIG. 2, and the same symbols indicate the same contents.

In FIG. 6, after the power is turned on again, the lead-in data is first read in (1), and the last time information (content of A ₀ ) is reset in (2) to (5) or the valid time is read. If it is determined that the information is not information, the disc is played from the first song in the processing after (10). On the other hand, if the last time information is determined to be valid in (2) to (5), the last time information of A ₀ is A _Q. Save to a register that has an address (A _Q does not have to be non-volatile),
At (8), the state of the sequential play switch is checked.
Here, if the sequential play switch is ON (sequential play execution command), the timer is reset and started in (12) to search for the playback position indicated by A ₀ and play, and conversely the sequential switch is OFF (non-execution command). If so, go through (10) and start playing the first song on the disc. Here, the flag S indicates the state of the sequential play switch, and when S = 0, the switch is OFF, S = 1.
The switch is ON.

At (13), the first disc or the song indicated by A ₀ is searched and the performance is started. At (14) and (15), new song number and time information are always written in A ₀ , while at (16). The elapsed time of the timer is checked, and if the time T of the timer is less than the time limit T _max , the state of the sequential play switch is checked in (17). (20) detects the change in the state of the switch by taking the exclusive OR of the state S of the previous switch and the state S'of the current switch, and if the state has not changed (S + S '= 0) On the other hand, if there is a change in the state of the switch, the following processing is performed. Sequential play was previously executed (S = 1), and the switch is now OFF.
If you have a (S '= 0) to stop the sequential play, to transfer the data of the disk the first track to the A ₀ perform the play from the first track (21) to (23).

On the other hand, the sequential play has not been executed before (S = 0), and the switch is now turned ON (S ′ =
In the case of 1), if there is the regular last time information saved in A _Q in (24), the contents of A _Q are restored to A ₀ in (26) to perform sequential play, while (2
If _AQ is reset in 4), continue playing. If it is determined in (16) that the timer time exceeds the time limit T _max , then the state of the sequential switch is ignored. (27) The subsequent processing is the same as in the case of FIG. In FIG. 6, the processing such as the operation input switch in FIG. 2 is omitted for the sake of explanation. In the above-described embodiment, it is also possible to store the operation command itself when the power is turned off, as a countermeasure against a case where a sporadic operation such as a cueing operation is given and the power is stopped before the operation is completed. . Even if the compact disc standard is changed, the present invention can be applied as long as the information about time, song number, etc. is recorded on the disc.

As described above, according to the present invention, the magnetic disk
Disc or a record carrier using an optical disc.
The last time information and program information
And pointer information when the DC power supply is cut off
Stored in the storage means, and the operation after the DC power supply is restored is initialized.
It is the subsequent playback operation and the second determination means is within a certain time.
When it is determined that it is, the playback operation after the above initialization is stopped.
Based on the data stored in the storage means
It is configured to have an execution operation input means for reproducing.
So, in the case of a short interruption period, the same song can be played from the same place.
It is possible to improve the operability such as
Time and time can be omitted. Also, during a power outage
It is effective to reflect the operator's intention change immediately after the reproduction .

[Brief description of drawings]

FIG. 1 is a block diagram of a compact disc player showing an embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of FIG.

FIG. 3 is a diagram for explaining a part of the configuration of FIG. 1;

FIG. 4 is a block diagram showing a configuration of a main part in the embodiment of the present invention.

FIG. 5 is a flowchart showing the operation of FIG. 4;

FIG. 6 is a flow chart showing the operation of the embodiment of the present invention.

FIG. 7 is a block diagram of a conventional compact disc player.

FIG. 8 is a diagram for explaining signals recorded on a compact disc.

FIG. 9 is a diagram for explaining signals recorded on a compact disc.

FIG. 10 is a flowchart of time reading in a compact disc player.

FIG. 11 is a flowchart of a search in the compact disc player.

[Explanation of Codes] 1 Compact Disc 3 Optical Pickup 5 Clock Reproducing Circuit 6 Demodulator 14 System Controller 17 Battery (Backup Power Supply) 18 Semiconductor Memory (Storage Means) 20 DC Power Supply 21 Power Drop Detection Circuit

Claims (1)

[Claims] 1. A power source is supplied from a direct current power source of a vehicle and re-powered.
Record carrier using a produced magnetic disk or optical disk
The last time information in the data on the playback progress stage of
Information, program information and pointer information to the above DC power supply
When the supply is cut off, the storage means for storing the
Power is supplied to the storage means during the interruption of the power supply.
The backup power supply to be
The first judgment to determine whether or not the specified fixed time has been exceeded
The cutoff period is determined by the determining means and the first determining means.
When it is determined that it is less than a certain time, it is recorded in the storage means.
Perform a playback operation based on the stored data
The cutoff period is longer than the above fixed time.
When it is turned off, it is decided to initialize the playback operation and play it back.
Determining means and the elapsed time after the start of the initialization reproduction operation
Determines whether is within a predetermined time
Second determination means and the operation after the interruption period is initialized
It is the subsequent reproduction operation and the predetermined time of the second judging means.
If it is within the range, the playback operation after the above initialization is stopped and the above
Playback is performed based on the above data stored in the storage means.
An apparatus for reproducing a record carrier, comprising: an execution operation input means for causing the determining means to select the above .