JP3065453B2 - Audio equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an audio device having a master unit connected by an audio bus for transmitting an audio signal and an audio control unit having at least a volume for adjusting the level of an input audio signal.

[0002]

2. Description of the Related Art This type of audio apparatus having a master unit and an audio control unit has a level (not referred to as a non-fader level in this specification) which does not pass through a master unit 31 and output level adjusting means as shown in FIG. ) Comprising slave units 32 and 33 composed of audio source devices for outputting reproduced audio signals, and an audio control unit 34, and a control assigned to the pressed instruction key by pressing an instruction key provided on the master unit 31. Transfer data to data bus line 3
5, the slave unit 32 or 33 is selected based on the control data, and the selected slave unit is controlled to a specified reproduction state based on the control data, and the reproduced audio signal is transmitted to the audio bus. The data is sent to the master unit 31 via the line 36.

The output level of the supplied reproduced audio signal is controlled by a volume control volume provided in the master unit 31, and the reproduced audio signal whose output level is controlled is transmitted to the audio control unit 34.
The output level is controlled again by the volume control volume provided in the audio control unit 34, and the amplifier 3
7 and amplified, and then the speaker 38 was driven.

[0004]

However, in the case of the above-described conventional audio device, the output level of the reproduced audio signal is controlled by a volume control volume in the master unit, and the output level is further controlled by a volume control volume in the audio control unit. Since the output level is controlled, there is a problem that when the level of the output audio signal is minimized in the master unit, the S / N of the reproduced audio signal received by the audio control unit deteriorates.

Further, when the output of the buzzer is transmitted from the last stage of the master unit, the output level of the buzzer is controlled by the volume control volume in the audio control unit. There is a problem that the beep sound changes depending on the adjustment position of the control volume, and the function as an operation buzzer is deteriorated.

Further, when an audio device is mounted on a vehicle or the like, an instantaneous power failure occurs only in the audio control unit, or when the audio control unit breaks down, the reproduced output sound is lost. there were.

According to the present invention, it is possible to improve the S / N of a signal received by an audio control unit, reduce a change in buzzer output sound, and generate a reproduction output sound even when the audio control unit fails. It is an object to provide an audio device.

[0008]

An audio device according to the present invention is connected to an audio bus through which an audio signal is transmitted.
Master unit and input audio signal level
Audio bus with first volume for adjustment
Audio as an external audio device selectively connected to the
Audio device having a video control unit.
The master unit is an audio source
Audio signal from the
Switching means for selecting one of the selected audio signals
And the level of the audio signal output from the first switching means
Adjust the second volume and connect it to the audio bus
Input the audio signal and output it to the first switching means
Or turn on the output audio signal of the second volume.
A second switch for selecting one of output to the Diobus
And the audio signal from the second volume and the audio
Audio signal from the audio control unit
The third switching means and the audio control unit
Detecting means for detecting whether or not it is connected to the DIO bus
Detects that the audio control unit is connected.
Output of the second volume to the audio bus
Switch the second switching means to the input side and
The third side is selected on the audio signal selection side from the audio control unit.
Switch the switching means and determine the second volume in advance
And the audio control unit is connected.
Is detected via the audio bus
Switch the second switching means to the side where the audio signal
To the output selection side from the second volume.
Switch the switching means 3 and operate the second volume
And control means for setting a set value based on the setting of the key .

[0009] The audio apparatus according to the present invention is characterized in that the predetermined set value of the second volume is a set value for outputting an input with no attenuation.

The audio device of the present invention operates the operation keys.
New control means for driving and controlling the buzzer signal source during operation
And it said that there were pictures.

[0011]

In the audio device according to the present invention, the master unit becomes bidirectional for input and output with respect to the audio bus by the second switching means. When the audio control unit is connected, the master unit is in an output state with respect to the audio bus, an audio signal from an internal audio source is selected by the first switching means, and the second volume and the second volume are selected . Audio bus via switching means
To the audio control unit, the output level of which is controlled by the first volume, and
It is output via the switching means. In this case, the second volume
The volume setting is set to a predetermined unattenuated setting.
Output level is set to the first volume
In the transferred state, the output level is controlled by the first volume, and the S / N does not decrease.

When the audio control unit is not connected , the master unit is in an input state with respect to the audio bus, and one of the audio signal input through the audio bus and the audio signal from the internal audio source is output. is selected by the first switching means, selection
The selected audio signal is the second volume and the third audio signal .
Through the selection means Ru is output. In this state, the audio control unit is not connected, but the audio signal is output even in this case, and the output level is controlled by the second volume.
Therefore, the S / N does not decrease.

When the operation key is operated, the buzzer is driven and a beep sound is generated. However, since a buzzer signal source is provided at the final stage of output, the beep sound increases and decreases regardless of the setting of the first volume. Such a thing disappears.

[0014]

The present invention will be described below with reference to examples. FIG.
FIG. 1 is a block diagram showing a configuration of an embodiment of an audio device of the present invention.

The audio apparatus of this embodiment includes a master unit 1 and an audio control unit 17, a slave unit 15 composed of, for example, a CD player for outputting a non-fader level reproduced audio signal, and a non-fader level reproduced audio signal for example. It comprises a slave unit 16 composed of a digital audio tape reproducing device, an amplifier 12 for amplifying a reproduced audio signal, and a speaker 13 driven by the output of the amplifier 12.

The master unit 1 controls the microcomputer 2, changeover switch circuits 3, 4 and 6 which are switched under the control of the microcomputer 2, an electronic volume 5 for controlling the output level, and on / off of the output. Buzzer output circuit 7, for example, a cassette tape reproducing device 8 for outputting a non-fader level reproduced audio signal
It also includes, for example, a tuner 9 for outputting a non-fader level reproduced audio signal, a mute circuit 10 for muting the reproduced audio signal supplied to the amplifier 12, and a power switch 11 for supplying power.

The microcomputer 2 sends connection confirmation data for connection confirmation to the slave units 15 and 16 and the audio control unit 17 via the data bus 18, and transmits data from the slave units 15 and 16 and the audio control unit 17 to the data bus. Upon receiving the connection check data output to the master unit 1 via the connection unit 18 and confirming the connection, the state control data is transmitted to the slave units 15 and 16 via the data bus 18 and the slave units 15 and 16 are transmitted to the state control data. To the reproduction operation state based on the instruction.

The switch circuit 3 selects whether to send the output of the electronic volume 4 to the audio bus 19 or to supply the audio signal from the audio bus 19 to the switch circuit 4. The changeover switch circuit 4 selects one of the reproduced audio signal from the cassette tape reproducing device 8, the reproduced audio signal from the tuner 9, and the audio signal from the changeover switch circuit 3 and sends them to the electronic volume 5. The changeover switch circuit 6 has an audio feedback line 20.
One of an audio feedback signal from the audio control unit 17 and an output audio signal from the electronic volume 5 which are supplied through the audio control unit 17 are selected and supplied to the mute circuit 10.

The audio control unit 17 comprises a microcomputer 21 and an audio bus 1 as shown in FIG.
An electronic volume 22, a buzzer output circuit 23, which adjusts the output level of the audio signal supplied via the power supply 9, and a mute circuit 24 to which the output of the electronic volume 22 and the output of the buzzer output circuit 23 are input. The output of 24 is an audio feedback signal to the master unit 1. The microcomputer 21 is a data bus 1
Upon receiving the control data supplied through the control unit 8, the electronic volume 22, the buzzer output circuit 23, and the mute circuit 24 are controlled based on the control data.

The operation of the embodiment constructed as described above will be described with reference to the flow charts shown in FIGS.

When detecting that the power switch 11 has been turned on (step S1), the mute circuits 10 and 24 are controlled to be in a mute state (step S1).
2) Noise at power-on is prevented, and slave units 15 and 16, audio control unit 17, amplifier 1
2 is supplied with power (step S3). Step S
Subsequent to 3, connection confirmation data is sent from the master unit 1 for connection confirmation, and communication for connection check is performed (step S4). The master unit 1 receives the confirmation data sent from the slave units 15 and 16 and the audio control unit 17 connected by the communication for confirming the connection, and confirms that the connection is established (step S5). . In step S5, there is a case where no slave unit or the like is connected, so that the confirmation is completed after waiting for a predetermined period.

After step S5, the master unit 1
It is determined whether there is an audio final stage other than (step S6). Here, the audio final stage is a device having an output stage for outputting a signal to the amplifier 12 to drive the speaker, and is referred to as an audio final stage, and corresponds to a case of an audio control unit with a speaker output as in a modified embodiment described later. . Therefore, in this embodiment, it is determined in step S6 that there is no audio final stage.

Subsequent to step S6, a search is made as to whether the audio control unit 17 is connected (step S9). As a result of the search in step S9, when it is determined that the audio control unit 17 is not connected, the terminals a and c are connected in the changeover switch circuit 3, and the audio bus 19 to the master unit 1 is connected to the input side. (Step S10), the terminals d and f are connected in the changeover switch circuit 6, the audio feedback input line 20 is controlled to the off state (step S11), and the electronic volume 5 is set to a desired value, that is, Is controlled so as to output the level set by a key or the like (step S12).

After step S12, the changeover switch circuit 4 is switched to a terminal based on the reproduction source (step S13). Therefore, by executing step S13, the output level of the playback audio signal from the source controlled to the playback state based on the control data sent from the microcomputer 2 is controlled in the electronic volume 5, and the playback in which the output level is controlled is performed. The audio signal is transmitted to the input terminal of the mute circuit 10. Subsequent to step S13, the mute of the mute circuit 10 is released (step S14). Therefore, the reproduced audio signal controlled to the desired output level is output to the amplifier 12, amplified, and reproduced as sound by the speaker 13.

As a result of the search in step S9, when it is determined that the audio control unit 17 is connected, the terminals a and b are connected in the changeover switch circuit 4, and the audio bus 19 to the master unit 1 is connected.
Is set on the output side (step S15). This is to make it possible to output a playback audio signal from a play source in the master unit 1. Subsequent to step S15, the terminals e and f are connected in the changeover switch circuit 6, and the audio feedback input line 20 is controlled to be turned on (step S16).

Subsequent to step S16, the microcomputer 2 is controlled via the microcomputer 21 to control the electronic volume 22 to a desired value, that is, an output of a level set from outside (step S17). The electronic control volume 5 is controlled to control the output of the volume 5 to the non-fader level (step S18), and then step S13 is executed.

Therefore, steps S9 and S1
When steps S5 to S18 are executed, when the source is the internal source, the changeover switch circuit 4 is switched to the reproduction audio signal side of the source selected by the control data, and the reproduction audio signal from the selected source is transmitted to the electronic volume 5 and The reproduced audio signal transmitted to the audio bus 19 via the changeover switch circuit 3 and input to the audio control unit 17, the output level of which is controlled by the electronic control volume 22, and the output level of which is controlled by the electronic volume 22, is The signal is guided to and amplified by the amplifier 12 via the changeover switch circuit 6 and the mute circuit 10, and the speaker 13 is driven. Therefore, in this case, since the output of the electronic volume 5 is controlled to the non-fader level, the S / N does not deteriorate.

The slave unit 15 or 16
Is selected, the changeover switch circuit 4 is switched to the output side of the changeover switch circuit 3, the internal source is substantially cut off, and the reproduced audio signal output from the selected slave unit 15 or 16 is output as an audio signal. The reproduced audio signal which is input to the control unit 17 and is level-controlled by the electronic volume 22 is guided to the amplifier 12 via the changeover switch circuit 6 and the mute circuit 10 and amplified, and the speaker 13 is driven. . Therefore, in this case, the output of the electronic volume 5 is substantially disconnected, and the output level of the reproduced audio signal is controlled only by the electronic control volume 22, so that the S / N does not deteriorate.

Next, when the audio control unit 17 is connected,
The protection action in the event that the device breaks down or is removed will be described.

When the audio change setting such as the change of the reproduction slave unit is made in the master unit 1 (step S19), it is checked whether or not the audio control unit 17 is connected to the master unit 1 (step S20). . Audio control unit 1
If the audio control unit 17 is removed or is out of order, it is determined that the audio control unit 17 is not provided, and the electronic volume 5 is controlled to output a desired value, that is, a level set from outside (step S21). ).

When it is determined that the audio control unit 17 is connected and has not failed, control data corresponding to the state to be changed is transmitted to the audio control unit 17 and communication with the audio control unit 17 is performed. (Step S22), audio control unit 1
7 is received, and it is checked whether or not the communication in step S22 is successful (step S23).
In this case, the communication is successful by receiving the confirmation data,
Unsuccessful communication is determined to be unsuccessful when confirmation data cannot be received as a result of a plurality of communications.

When it is determined in step S23 that the communication is unsuccessful, the mute circuit 10 is controlled to be in a mute state (step S24), and the terminal a and the terminal c are connected in the changeover switch circuit 4 to the master unit 1. Is set to the input side (step S2).
5) The terminal d and the terminal f are connected in the changeover switch circuit 6, and the audio feedback input line 20 is controlled to an off state (step S26). Next, the electronic volume control 5 is controlled to output the desired value, that is, the output of the level set from the outside (step S27). Subsequently, the mute circuit 10 is controlled to the mute release state (step S24), and the audio control unit 17 is controlled. Is connected (step S2).
9).

As a result, when it is determined that the audio control unit 17 is not connected, and the audio change setting is performed next, the master unit 1 controls the electronic volume 5.

In this embodiment, when a key is pressed or the like, a buzzer request is issued. When there is a buzzer request (step S30), the master unit 1 checks whether there is an external buzzer at the time of connection check (step S31), and when it is determined that there is no external buzzer, the output of the internal buzzer is turned off. Output from the buzzer output circuit 7 (step S32), a beep sound is generated. When the audio control unit 17 has a buzzer output circuit 23 as shown in FIG. 2, it is determined that an external buzzer is present, and buzzer frequency data and sounding frequency data are sent from the microcomputer 2 to the microcomputer 21. The buzzer output circuit 23 is controlled based on the above control, and the output from the audio control unit 17 via the changeover switch circuit 6 and the mute circuit 10 causes the buzzer output circuit 23 to output
A beep is sounded the number of times based on the number-of-sounds data (step S33). In this case, since the beep sound has nothing to do with the control of the electronic volume 22, a beep sound of a constant volume is emitted.

In this case, when the microcomputer 21 receives the buzzer frequency data and the number of times of sounding (step S34), it is checked whether the buzzer output is permitted (step S35). ). If the buzzer output has been permitted, a beep sound is output based on the output from the buzzer output circuit 23 (step S36). If the permission has not been given, the buzzer output circuit 23 of the audio control unit 17 is controlled to the off state, and there is no output from the buzzer output circuit 23.

Next, a modified embodiment will be described. FIG. 9 is a block diagram showing the configuration of the modified embodiment. In this modification, the output of the audio control unit 17 is
2 is an audio control unit 27 with a loudspeaker output configured to transmit to the master unit 2 and the audio feedback input of the master unit 1 is eliminated.

[0037] In the case of this modified example, the step S6 it is determined that there is an audio final stage (see FIG. 3), an external buzzer has a storage Following step S 6, the buzzer output enable audio final stage, That is, it is output to the audio control unit 27 (step S8),
Next, step S9 is executed. Therefore, in step S35 (see FIG. 8), it is determined that the buzzer output is permitted, the output is sent from the buzzer output circuit 23, and a beep sound is generated.

Although the audio control units 17 and 27 control the electronic volume 22 in the description of the above-described embodiment and the modified example, not only the electronic volume 22 but also an equalizer and a channel divider are controlled. You may make it.

[0039]

As described above, according to the audio apparatus of the present invention, when the audio control unit is connected, the second volume is set to a set value such as no attenuation.
Since the output level is set by the first volume, there is an effect that the S / N does not decrease . Also, when the audio control unit is not connected operating keys
Output by the second volume set to the set value
Since the audio signal whose level is controlled is output from the master unit , it is possible to eliminate the case where the audio signal is not output even in this case.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of an audio control unit according to one embodiment of the present invention.

FIG. 3 is a flowchart for explaining the operation of one embodiment of the present invention.

FIG. 4 is a flowchart for explaining the operation of an embodiment of the present invention.

FIG. 5 is a flowchart for explaining the operation of an embodiment of the present invention.

FIG. 6 is a flowchart for explaining the operation of one embodiment of the present invention.

FIG. 7 is a flowchart for explaining the operation of one embodiment of the present invention.

FIG. 8 is a flowchart for explaining the operation of one embodiment of the present invention.

FIG. 9 is a block diagram showing a configuration of a modified example of the present invention.

FIG. 10 is a block diagram illustrating a configuration of a conventional audio device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Master unit 2 and 21 Microcomputer 3, 4 and 6 Changeover switch circuit 5 and 22 Electronic volume 8 Cassette tape reproducing device 9 Tuner 12 Amplifier 15 and 16 Slave unit 17 Audio control unit 23 Buzzer output circuit

Claims (3)

(57) [Claims] An audio bus through which an audio signal is transmitted.
Master unit connected to the
Audio with a first volume for level adjustment
External audio device that is selectively connected to the
Audio device having two audio control units
A is the master unit, and the audio signal from the audio source provided inside
Audio signal input via the audio bus
A first switch for selecting one of the switches, and a level of an audio signal output from the first switch.
A second volume to be connected and an audio signal connected to the audio bus
Output to the first switching means or output of the second volume
Output one of the audio signals to the audio bus
A second switching means for selecting, an audio signal from the second volume and an audio control
Select one of the audio signals from the control unit
3 and the audio control unit is connected to the audio bus.
Detection means for detecting whether or not the audio control unit has been connected.
Output the output of the second volume to the audio bus.
Switch the second switching means to the
Third switching to audio signal selection side from control unit
Means and switch the second volume to a predetermined setting.
Default value and detected that the audio control unit is not connected
Audio signal supplied through the audio bus
Switching the second switching means to the input side of the signal,
A third switching means is provided on the output selection side from the second volume.
Switch and set the second volume based on the operation key setting.
An audio apparatus comprising: a control unit that sets a set value based on the set value . 2. The audio device according to claim 1, wherein
The audio device according to claim 1, wherein the predetermined setting value of the second volume is a setting value for outputting the input with no attenuation. 3. The audio device according to claim 1, wherein
A new drive control of the buzzer signal source when operating the operation key
An audio device comprising control means .