JPH06249926A - Apparatus equipped with self-diagnostic function - Google Patents

Abstract

PURPOSE:To perform a self-diagnosis without a need for a special in jig and to detect an abnormal part in each circuit block even during the operation of an apparatus. CONSTITUTION:A tuner 3 selects an RF signal in one band out of frequency- multiplexed RF signals, and it converts the RF signal into an IF signal. A demodulation circuit 4 demodulates the IF signal and it outputs signal data. A demultiplexer 5 releases a time-division multiplex, it takes out data at one frame, it performs an error-correction decoding processing operation, and it takes out an audio channel and a data channel. An expansion circuit 6 performs an expansion operation and a volume operation. A microprocessor 9 performs the self-diagnosis of the tuner 3, the multiplexer 5, the expansion circuit 6, a D/A converter 7 and an amplifier 8 in a test mode. In addition, the microprocessor 9 performs a tuning operation by the tuner 3 and a muting operation or a muting release operation on the basis of the result of an error processing operation by the multiplexer 5 in an ordinary operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device with a self-diagnosis function, which can perform a function diagnosis on a plurality of built-in circuit blocks.

[0002]

2. Description of the Related Art Generally, a system is considered in which audio signals can be individually heard by headphones or earphones at a plurality of seats in a vehicle such as an aircraft, and audio signals of a large number of channels can be freely selected at each seat. Has been.

A large number of devices are provided on the signal sending side and the signal receiving side of such a system, and a large number of circuits are also provided on each device. For example, in an aircraft, a signal receiving unit that allows passengers to operate for each of a plurality of seats is provided. Since each signal receiving unit includes a plurality of circuits, the number of the entire cabin is enormous. Become.

[0004]

By the way, as described above, maintenance is difficult and time consuming and labor-intensive in a huge number of circuits or in a special use environment such as in an aircraft.

Further, when a failure occurs in the equipment, special measuring equipment and inspection are required to identify the failure location.

The present invention has been made in view of the above circumstances, and provides a device with a self-diagnosis function capable of identifying an abnormal portion for each circuit block even during operation of a device without requiring a special jig. To aim.

[0007]

A device with a self-diagnosis function according to the present invention is a device with a self-diagnosis function for performing self-diagnosis on a plurality of built-in circuit blocks. The first self-diagnosis using the data and the second self-diagnosis using the signal dedicated to the test are distinguished, and the first self-diagnosis is performed during normal operation of the device, including when the power of the device is turned on. In order to solve the above problems, at least a second self-diagnosis is performed in the test mode.

Here, it is preferable that the first self-diagnosis is also performed in the test mode including the power-on.

Further, the above-mentioned signal is a signal which is subjected to predetermined processing in each circuit so as to exhibit the original function of the device during normal operation of the device. Further, it is preferable that the signal is previously subjected to error detection coding, and the first self-diagnosis is performed using error detection information obtained by the error detection code in this signal.

The output signal from the device may be muted according to the result of the first self-diagnosis or the second self-diagnosis.

[0011]

The device with self-diagnosis function according to the present invention performs the first self-diagnosis using the error detection information obtained by the error detection code in the signal which has been error detection coded in advance during the normal operation, and the device concerned. The second self-diagnosis using at least the test-dedicated signal is performed during the test mode including the power-on of the device, so no special jig is required and abnormal parts of each circuit block are detected even during operation of the device. it can.

[0012]

Embodiments of the self-diagnosis function-equipped device according to the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of a first embodiment in which the present invention is applied to an audio signal receiving device having a plurality of circuit blocks.

The first embodiment has a function of appropriately performing self-diagnosis on the built-in RF reception demodulation circuit 2, demultiplexer 5, expansion circuit 6, D / A converter 7 and amplifier 8. .

This self-diagnosis is performed not only when the power of the apparatus is turned on and when the test mode or the like provided in the apparatus is operated to shift, but also during normal operation of the apparatus.

When the first embodiment is in normal operation, that is, in a state in which a transmitted audio signal transmitted from an audio signal transmitting device is received and a predetermined process is performed to let a listener listen to music or the like. At the time of, error detection information (error flag) obtained by the error detection code in the transmission audio signal which has been error detection coded in advance.
Self-diagnosis using.

Further, at the time of power-on or in the test mode (when the mode is shifted by the operation of the test mode switch or the like), the first embodiment uses at least a test-specific signal. Diagnosing.

Here, before explaining the self-diagnosis function performed by the first embodiment, the schematic configuration of the first embodiment will be described.

In FIG. 1, the RF signal transmitted from the audio signal transmitting apparatus is input from the input terminal 1 in the first embodiment.

The RF signal input from the input terminal 1 is R
The signal is sent to the tuner 3 of the F reception demodulation circuit unit 2. The tuner 3 selects (tunes, tunes) an RF signal in one band of the frequency-multiplexed RF signals and outputs the IF signal.
The signal is converted to an (intermediate frequency) signal and sent to the demodulation circuit 4. The demodulation circuit 4 demodulates this IF signal to output serial data having a data rate of 6.144 MHz, for example, and sends it to the demultiplexer 5.

The serial data supplied to the demultiplexer 5 is time division multiplexed data. The demultiplexer 5 solves this time division multiplexing, extracts data corresponding to, for example, one frame, performs error correction decoding processing (for example, BCH decoding processing) for each frame, and then outputs a desired audio channel or data. Take out the channel. This error correction processing is for detecting and correcting a data inversion error that may occur due to the influence of noise or the like during transmission / reception of an RF signal. Further, selection of an arbitrary audio channel or data channel performed by the demultiplexer 5 is performed according to a command (slot setting) from the microprocessor 9.

Any audio channel or data channel selected by the demultiplexer 5 is supplied to the decompression circuit 6. The decompression circuit 6 is designed so that the first decompression mode and the second decompression mode can be switched and controlled. The mode switching and volume (volume) setting are performed according to a command from the microprocessor 9. Be seen. The audio channel and the data channel expanded by the expansion circuit 6 are supplied to the D / A converter 7.

The D / A converter 7 converts the audio channel expanded by the expansion circuit 6 into, for example, a 2-channel analog audio signal and sends it to the amplifier 8.

The analog audio signal amplified by the amplifier 8 is supplied to, for example, headphones via the output terminal 10.

Next, the self-diagnosis function of the first embodiment will be described. In this self-diagnosis function, the microprocessor 9 determines the current state of the device (whether it is in normal operation or during testing and power-on), and the microprocessor 9 applies a self-diagnosis start command corresponding to the state. It is started by giving each circuit block to. Then, based on the check results from the corresponding circuit blocks, the microprocessor 9 determines whether each circuit block is normal (abnormal).

The microprocessor 9 diagnoses the functions of the central processing unit (CPU), random access memory (RAM), read only memory (ROM) and so-called watchdog timer.

Further, this microprocessor 9 has a result of any trouble or failure in any of tuning by the tuner 3, demodulation by the demodulation circuit 4 and the above-mentioned error processing by the demultiplexer 5 during the normal operation of the device. (Error detection output, etc.) is read and stored in memory or the like. This can be checked by calculating an error correction code (BCH code, etc.) added in advance to the transmission signal by the demultiplexer 5 and reading the error flag, and writing the result in a memory or the like, and controlling the mute state, for example. Alternatively, control may be performed such that the mute is not released if the mute state is currently set.

Further, the microprocessor 9 causes the tuner 3 to switch the reception bands of all the audio bands, for example, 4 bands in the test mode including the power-on, and causes the demultiplexer 5 to detect the error detection information. Based on the result, it is confirmed whether the demultiplexer 5 or the tuner 3 is operating normally. In addition, the microprocessor 9 has a decompression circuit 6 of, for example, 1 kHz.
Output the sine wave test data of D / A converter 7,
Received via the amplifier 8. Then, the microprocessor 9 detects the sine wave of 1 kHz by the built-in A / D conversion circuit, and confirms that the operation of each part operates normally. Further, the microprocessor 9 causes the decompression circuit 6 to output a 0 level signal to the D / A converter 7 in the test mode including power-on, and the so-called 0 input terminal 7a of the D / A converter 7 is used. Monitor the output of D / A
Check whether the converter 7 is operating normally.

The details of the self-diagnosis function of the first embodiment will be described below with reference to FIGS. 2 to 7.

FIG. 2 is a flow chart for explaining the self-diagnosis (hereinafter appropriately referred to as check) function in the test mode including the power-on of the apparatus.

When the flow of FIG. 2 is started, step S
1, the demultiplexer 5 is checked, and step S2
Then, the tuner 3 is checked, and in step S3, the expansion circuit 6, the D / A converter 7 and the amplifier 8 are checked.

FIG. 3 is a flow chart for explaining the self-diagnosis function during normal operation of the apparatus. In FIG. 3, the demultiplexer 5 reads the error detection information (error flag) from the error detection code in the transmission audio signal that has been error detection coded in advance, and the multiplexer 9 writes the result in a memory or the like to mute the output signal. Or, decide to cancel the mute.

Next, FIG. 4 is a flow chart showing the flow of checking the demultiplexer 5. When this flow is started, the tuner 3 is set to 159 in step S11.
Set to MHZ and check tuner 3 in step S12.

Similarly, in step S13, the tuner 3 is set to 153 MHz, and the tuner 3 is checked in step S14.

In step S15, the tuner 3 is set to 147.
Set to MHZ and check tuner 3 in step S16.

In step S17, the tuner 3 is set to 141
Set to MHZ and check tuner 3 in step S18.

Then, the tuner 3 is set to 1 in step S19.
When the frequency is 41 MHz, it is determined whether or not it is normal, and if YES is determined, the process proceeds to step S23, the OK status that the demultiplexer 5 is normal is set, and if NO is determined, the process proceeds to step S20.

In step S20, the tuner 3 outputs 147
When the frequency is MHZ, it is determined whether or not it is normal, and if YES is determined, the process proceeds to step S23, the OK status that the demultiplexer 5 is normal is set, and if NO is determined, the process proceeds to step S21.

In step S21, the tuner 3 is set to 153
When it is MHZ, it is determined whether it is normal, and if YES is determined, the process proceeds to step S23, the OK status that the demultiplexer 5 is normal is set, and if NO is determined, the process proceeds to step S22.

In step S22, the tuner 3 outputs 159
When the frequency is MHZ, it is determined whether or not it is normal, and if YES is determined, the process proceeds to step S23, the OK status that the demultiplexer 5 is normal is set, and if NO is determined, the process proceeds to step S24.

A step S24 sets the NG status that the demultiplexer 5 is out of order.

That is, the check of the demultiplexer 5 causes the tuner 3 to switch the reception band of four bands, and if the determination of all bands is NO, the NG status indicating that the demultiplexer 5 is out of order is set. If only the determination of one channel is NO, the demultiplexer 5 sets the OK status indicating normal.

Next, FIG. 5 is a flow chart showing the flow of checking the tuner 3. When this flow is started, it is determined in step S31 whether the number of samples at the time of sampling the error flag when the band is switched by the tuner 2 has reached a predetermined number n ₁ . YE here
If S is determined, the process proceeds to step S23, and if NO is determined, it becomes RTS.

In step S32, it is determined whether or not there is a tuner error by, for example, comparing the number of error flags in the number of samples of the predetermined number n ₁ with a preset threshold value. If YES is determined here, the process proceeds to step S33,
The error counter is incremented by +1. Also,
If NO is determined here, the process advances to step S34 to save the tuner OK status that the tuner is normal.

In step S35, it is determined from the +1 increment in step S33 whether or not there are three consecutive errors. If YES is determined here, the process proceeds to step S36 to save the tuner NG status that the tuner is out of order. Here, if NO is determined, it becomes RTS.

FIG. 6 is a flow chart showing a check flow of the expansion circuit 6, the D / A converter 7 and the amplifier 8.

When this flow is started, step S4
At 1, the expansion circuit 6 is set to the test mode (test start mode). According to this test mode, the expansion circuit 6 converts the sine wave (sine wave) of 1 kHz into the D / A converter 7,
It is supplied to the microprocessor 9 via the amplifier 8.
Then, the built-in A / D converter of the microprocessor 9 checks the test frequency of 1 KHz in step S42, and the microprocessor 9 determines in step S43 whether the test result is normal or not. Here, if YES is determined, the process proceeds to step S48, and the NG status that the expansion circuit 6 and the amplifier 8 are out of order is set, and if NO is determined, the process proceeds to step S44.

In step S44, the expansion circuit 6 is set to a test mode called 0 output mode. And step S
At 45, the expansion circuit 6 outputs a 0 level signal to the D / A converter 7, and the so-called 0 input detection terminal 7 of the D / A converter 7 is output.
The microprocessor 9 monitors the output from a, and D / A
Check the converter 7.

In step S46, it is determined whether or not the check result of the D / A converter 7 in step S45 is OK. Here, if YES is determined, the process proceeds to step S48, and the NG status that the expansion circuit 6 and the amplifier 8 are out of order is set, and if NO is determined, the process proceeds to step S47.

In step S47, the D / A converter NG status indicating that the D / A converter 7 is out of order is set.

FIG. 7 is a flow chart for explaining the details of the self-diagnosis based on the error detection information obtained from the error detection code in the normal operation shown in FIG.

In step S51, it is determined whether or not the tuner 3 has switched the band. Where YES
If it is determined to be RTS, RTS is determined, and if NO is determined, the process proceeds to step S52.

In step S52, the number of samples when sampling the error flag in the tuner 3 is a predetermined number n ₂
Is determined. If YES is determined here, the process proceeds to step S53, and if NO is determined, the RTS is performed.

In step S53, it is determined whether the error level is normal by comparing the number of error flags in the predetermined number n ₂ of samples with a preset threshold value. Here, if YES is determined, the process proceeds to step S54, mute is released, and if NO is determined, step S5 is performed.
Go to step 5 to mute.

After the mute is released in step S54, the flow advances to step S56 to save the OK status that the tuner is normal, and become RTS.

After muting in step S55, the process proceeds to step S57, saves the NG status that the tuner is out of order, and becomes RTS.

As described above, in the first embodiment, the error detection information (error flag) obtained by the error detection code contained in the audio transmission signal transmitted to the tuner 3 is used in the demultiplexer 5 in the normal operation. Is read out, and based on this result, the microprocessor 9 mutes the output signal or unmutes it. In the first embodiment, the operation of the demultiplexer 5 is confirmed by the judgment of the error of the plural band switching of the tuner 3 in the test mode including the power-on, and the error at the band switching of the tuner 3 is detected. The operation of the tuner 3 can be confirmed according to the frequency of occurrence of the test signal, and the decompression circuit 6 outputs test data, for example, a 1 KHz sine wave and a 0 level signal.
The operations of the / A converter 7, the expansion circuit 6 and the amplifier 8 are confirmed.

Next, an example in which the device with self-diagnosis function of the present invention is applied to an audio signal receiving device in an aircraft, that is, the configuration of the seat unit 140 side on the signal receiving side for receiving an audio signal is a second embodiment. However, first, a schematic configuration of a signal transmission system including the second embodiment and a schematic configuration of a signal sending side for sending a signal to the second embodiment will be described.

FIG. 8 is a block diagram showing a schematic configuration of the signal transmission system. In FIG. 8, the transmission signal source 1
In FIG. 10, for example, a video signal reproducing device 111 such as a so-called VTR (video tape recorder) or a video disc player and an audio signal reproducing device 11 such as a so-called CD (compact disc) player or a tape recorder 11 are provided.
2 and a computer data output device 113 such as TV game software. A so-called PA control device 1 having a function for in-flight broadcasting using a microphone, etc.
16 are provided.

Among the output signals from these devices, the audio or audio signals from the video signal reproducing device 111 and the audio signal reproducing device 112 and the computer data from the computer data output device 113 are sent to the audio signal transmitting device 120. Has been. The video signal from the video signal reproducing device 111 is sent to another video signal transmitting device (not shown), and the audio signal from the PA control device 116 is directly sent to a speaker (not shown) provided on the inside wall or ceiling of the aircraft. Audio signal transmitting device 12
It has also been sent to 0.

The audio signal transmitting device 120 includes, for example, up to four audio signal transmitting units 121A and 12A.
1B, 121C, 121D, and one audio signal transmission unit 121 multiplexes, for example, an audio signal of 32 channels and a data signal of 8 channels (or an audio signal of 36 channels), and a so-called RF modulator 122 It is modulated into an RF signal and output.
An RF mixing circuit for inputting and mixing RF output signals from other audio signal transmitting units is provided in the RF modulator 122. Specifically, each of the audio signal transmitting units 121A, 121B, 121C, 121D
The RF signals having different carrier frequencies are frequency-multiplexed and output. In this case, the video signal reproducing device 111
The video signals of a plurality of channels may be modulated with different carrier frequencies by an RF modulator (not shown), frequency-multiplexed with the RF modulated signal of the audio signal, and transmitted by one coaxial cable.

The frequency-multiplexed RF signal is sent to the RF branching unit 131 of the zone management unit 130 provided for each zone for dividing the inside of the aircraft into zones, and the RF branching unit 13
1 through the RF amplifier 132 to the zone management unit of the next zone. The RF signal input to the RF branching device 131 is branched and sent for each column which is a divided area for dividing the zone. A plurality of seat units 140 are connected in series in one column, and the R input to the seat unit 140 is input.
The F signal is sent to the next seat unit 140 via the RF branching device 141 and the RF amplifier 142.

In one seat unit 140, for example, 3
Circuits for seats are collectively provided, and the RF signal branched by the RF branching device 141 is divided into three RF signals by the RF distributor 144, and three RF receiving units 145 are provided.
A, 145B, 145C, respectively. The RF receiving unit 145 extracts an RF signal in one band of the frequency-multiplexed signal and performs RF demodulation, extracts a signal of a desired channel from the demodulated signal, and outputs the signal. The signals output from the RF receivers 145A, 145B, and 145C are transmitted to the passenger side control units 146A and 145C.
46B and 146C, respectively. The passengers in each seat can connect headphones 147A, 147B, and 147C to the control units 146A, 146B, and 146C, respectively, and arbitrarily select and listen to an audio signal of a desired channel.

Next, FIG. 9 is a block diagram showing a schematic configuration of the audio signal transmitting unit 121 on the audio signal transmitting side. The audio signal transmitting unit 121 shown in FIG. 9 inputs, for example, an audio signal of 32 channels and a data signal of 8 channels, converts it into a signal having a frequency band of 6 MHz, and outputs it. The audio signal sending unit 121 is also called an audio multiplexer unit or AMUX because it multiplexes and outputs audio signals.

The audio signal transmission unit 121 is supplied with 32 channels of audio signals AU _{1 to} AU _{32 in} the form of so-called balanced input, for example.
The buffer amplifier 21 converts the balanced input form into an unbalanced form. Buffer amplifier 2
The audio signals of 32 channels from 1 are grouped for every 2 channels (for example, stereo left and right channels), sent to the A / D converter 22, converted into digital signals, and sent to the signal compression circuit 23 to be compressed respectively. It is encoded. In the signal compression circuit 23, for example, a high-efficiency compression encoding process for adaptively controlling bit allocation for each band divided in the frequency axis direction according to an input signal by utilizing human auditory characteristics, or so-called AD
(Adaptive difference) PCM encoding processing and the like are performed.

Further, the computer data DT _{1 to} DT ₈ such as 8-channel TV game software is balanced-input according to the so-called EIA-422 interface format, and is converted into an unbalanced signal by the buffer amplifier 21. The digital data interface circuit Sent to 24.

Here, as the signal compression circuit 23, a first compression mode for performing a high-efficiency encoding process which takes a long processing time but has good reproduction sound quality by utilizing the human auditory characteristics and the like, and ADPCM and the like. A circuit capable of switching and selecting the second compression mode having a relatively short processing time is used.
Switch to the first compression mode when listening to audio signals such as music for each seat, and switch to the second compression mode when forcibly switching to the PA channel when a message from the captain is announced. It is preferable to switch. This is because the first compression mode is preferable when listening to music and the like because high sound quality is desired, and at the time of an announcement and the like, the sound from the speaker and the sound from the headphones provided on the wall or ceiling of the aircraft are combined. This is because the second compression mode, which has a small time difference between them, is preferable. The selection of the compression mode switching is performed by a control signal from the controller 30. As a specific example of the first compression mode, a so-called ATRAC (Adaptive T) used for so-called MD (mini disk) signal compression is used.
Ransform Acoustic Coding) method, so-called DCC
The so-called PASC (Precision Adaptive Sub-b) used for signal compression of (digital compact cassette)
and Coding) method or the like can be used.

The 32 channels of output signals from the signal compression circuit 23 are grouped into 12 channels (6 pairs of 2 channels) in order from the signal corresponding to AU ₁ of the original input audio signal. 25
A and 25B, respectively, and the rest of the above AU _{25 to} AU
Output signals of 8 channels (4 pairs) corresponding to ₃₂ and output signals from the digital data interface circuit 24 corresponding to the data of 8 channels (DT _{1 to} DT ₈ ) are collected and sent to the multiplexer 25C. To be The digital data interface circuit 2
The clock signal from 4 is taken out through the buffer amplifier.

Multiplexers 25A, 25B, 25C
Each handles a signal conforming to the audio signal format of a television broadcast signal of satellite broadcasting or satellite communication. One transmission frame of a format conforming to this audio signal format is composed of vertical 32 bits × horizontal 64 columns, and 128 bits of data per channel are included in 12 channels (for example, 12 audio channels or audio channels) in the 1 transmission frame. 8 channels + 8 channels of computer data) and so-called B
CH error correction code (eg (63, 50) BCH code),
At least a preamble such as frame synchronization and control code is included. One multiplexer 25
From the multiplexer 25A, 25B, and 25C, the data is output at a rate of 2.048 Mbps, and the data output from the multiplexers 25A, 25B, and 25C is sent to the time-division multiplexing circuit 26 to be time-division multiplexed. Will be output. The digital signal output from the time division multiplexing circuit 26 is waveform equalized by the equalizer 27, compressed into a band of 6 MHz, for example, and sent to the RF modulator 122.

In the RF modulator 122, the output signal from the equalizer 27 is modulated by the intermediate frequency modulator 31 into a predetermined intermediate frequency (IF) signal, which is amplified by the IF amplifier 32 and is multiplied by the multiplier (modulator). ) 33. The multiplier 33 supplies a predetermined RF signal from a PLL (phase locked loop) circuit 34.
A carrier wave signal having a frequency is supplied, and the frequency of the output signal of the PLL circuit 34 is controlled by the controller 30 using a CPU or the like. Multiplier 33
The output signal from the BPF is a bandpass filter (BPF) 35.
Via an RF amplifier 36 to an RF combiner (combiner or mixer) 37. The RF combiner 37 is connected to the RF combiner 37 via an external RF input terminal 126.
For example, the RF from the other audio signal transmitting unit described above.
Signal is being supplied. By making the RF carrier frequency of the RF modulator 122 different from the carrier frequency of the external RF input signal, the RF combiner 37 can perform frequency multiplexing. RF combiner 37
RF output signal from the output terminal 1 via the attenuator 38
It is taken out from 25.

That is, the RF in the RF modulator 122 is
The frequency is a signal output from the PLL circuit 34 when the controller 30 controls the frequency division ratio or the prescaler value in the PLL circuit 34 based on, for example, three program discrete signals supplied to the controller 30. The frequency is variably controlled, and the carrier frequency of the RF modulation signal from the multiplier 33 is variably controlled. That is, the program discrete signal causes RF
The carrier frequency of the signal is determined so that it does not match (is different from) the carrier frequencies of the RF signals from the other audio signal transmitting units. Also, external RF
When there is no RF signal input from the input terminal 126, the controller 30 receives the termination control signal from the external RF input terminal 126.
Is grounded, and the RF output terminal 125 is terminated.

Next, the audio signal transmitting unit 1
The self-diagnosis function of 21 will be described. The output signal from the time division multiplexing circuit 26 is demultiplexed by the demultiplexer 28 and sent to the controller 30 using a CPU or the like to determine whether or not the multiplexing process is normally performed. Further, the bit monitor 29 demodulates the RF signal from the RF combiner 37, and the controller 30 determines whether or not the RF signal is normal. The self-diagnosis (determination of normality) of the demultiplexer 28 and the bit monitor 29 uses, for example, an error correction code (BCH code or the like) added when the multiplexer 25 (25A, 25B, 25C) multiplexes. It may be calculated and judged based on the presence or absence of error, the amount of error, and the like.

For diagnosis of the A / D converter 21, the output signal from the A / D converter 21 is output to the controller 3
The operation can be confirmed by monitoring at 0. Signal compression circuit 2
For No. 3, switching to the forced self-diagnosis mode (test mode), for example, outputting a 1 kHz sine wave, returning this to an audio signal by the bit monitor 29, and monitoring the signal by the controller 30. You can diagnose by.

These self-diagnosis is performed by forcibly switching to the self-diagnosis mode at the time of power-on, maintenance, etc., as required, and regarding self-diagnosis using the error correction code added at the time of multiplexing. During the normal operation, it is periodically performed at a predetermined cycle. When a failure occurs, for example, the failure status and the time of occurrence are written in the non-volatile memory 30M, and the history is stored.

As for the output level of the RF output signal from the RF modulator 122, the gain of the RF amplifier 36 can be controlled by the controller 30. For this controller 30, a so-called EIA-485 interface, for example, is facilitated, through which the current failure status and failure history can be monitored and the output level of the RF signal can be controlled.

Next, the configuration of the seat unit 140 side on the signal receiving side for receiving the audio signal according to the second embodiment, particularly the configuration of the RF distributor 144 and thereafter will be described with reference to FIG.
This will be described in detail with reference to 0.

In FIG. 10, the RF signal branched by the RF branching device 141 of FIG. 8 is input to the input terminal 41, and the RF signal is divided into three RF signals by the RF distributor 144, so that the three RF receiving parts are received. It is sent to each input terminal 42A, 42B, 42C of 145A, 145B, 145C. These RF receivers 145A, 145B, 145C
Since the internal configurations are the same, the internal configuration is illustrated only for one RF receiving unit, for example, 145A, and the internal configurations of the other RF receiving units 145B and 145C are omitted. Further, the subscript A is omitted from the instruction code of each unit of the RF receiving unit 145A.

The RF signal input from the input terminal 42A of the RF reception section 145A is sent to the tuner 52 of the RF reception demodulation circuit 51. The tuner 52 includes audio signal transmitting units 121A, 121B, 121 shown in FIG.
An RF signal in one band of the RF signals frequency-multiplexed with different RF carrier frequencies for each C and 121D is selected (tuning, channel selection), converted into an IF (intermediate frequency) signal, and sent to the demodulation circuit 53. send. The demodulation circuit 53 uses this IF
The signal is demodulated to output the serial data having the data rate of 6.144 MHz and sent to the demultiplexer 54.

As described above, the serial data supplied to the demultiplexer 54 is time-division multiplexed for three (three frames) of the audio format of the television signal of the satellite broadcasting or the satellite communication. It was done. The demultiplexer 54 solves this time division multiplexing, takes out the data corresponding to one frame, performs the error correction decoding processing (for example, BCH decoding processing) for each frame, and then outputs the desired audio channel or data channel. It is to select and take out. The error correction processing is for detecting and correcting a data inversion error that may occur due to the influence of noise or the like during transmission / reception of an RF signal. The selection of the desired audio channel or data channel is performed according to a command from the microprocessor (so-called microcomputer) 43.

Here, when the time division multiplexing is solved and only the signal for one frame is taken out, the audio channel or the data channel is selected from the audio 12 channels or the audio 8 channels and the data 8 channels in one frame. In the demultiplexer 54 of this specific example, 2 audio channels can be arbitrarily selected from 32 audio channels and 8 data channels corresponding to 3 frames, or 1 data can be arbitrarily extracted. It is configured so that the channel can be selected. For this purpose, for example, when solving the time division multiplexing, the signals corresponding to arbitrary two frames may be taken out.

The data and clock selected by the demultiplexer 54 are taken out to the outside through the buffer amplifiers. The audio signals of the two channels (for example, stereo left and right channels) selected by the demultiplexer 54 are sent to the D / A converter 56 with or without the expansion circuit 55.

The decompression processing in the decompression circuit 55 is controlled so that the first decompression mode corresponding to the first compression mode and the second decompression mode corresponding to the second compression mode can be switched. This mode switching and volume (volume) setting are performed in accordance with a command from the microprocessor 43.

The D / A converter 56 receives, for example, 16-bit audio data expanded by the expansion circuit 55, outputs a 2-channel analog audio signal, and sends it to the headphone amplifier 57. Headphone amplifier 5
Reference numeral 7 is an amplifier for driving headphones 147 connected via the passenger side control unit 146 of FIG. 8, and the output signals thereof are left and right output terminals 47A _L , 47A.
Retrieved via _R.

Next, self-diagnosis of such a circuit will be described. First, the microprocessor 43 is a CPU,
Function diagnosis of each part such as RAM, ROM and so-called watchdog timer is performed. Also, tuning with the tuner 52,
If there is a trouble or failure in either the demodulation by the demodulation circuit 53 or the error processing by the demultiplexer 54, the result (error detection output or the like) is read by the microprocessor 43 and stored in a memory or the like. This can be checked by calculating an error correction code (BCH code or the like) added to the transmission signal in advance by the demultiplexer 54 and reading the error flag, and writing the result in a memory or the like, and controlling the so-called mute state, for example. Alternatively, control may be performed such that the mute is not canceled if the current mute state is set.

Further, at the time of audio self-diagnosis, the expansion circuit 55 outputs, for example, 1 KHz sine wave test data, and the output from the headphone amplifier 57 is sent to the microprocessor 43 via the D / A converter 56. The microprocessor 43 uses the built-in A / D
Detect with the converter, and confirm that each circuit operates normally. Further, the decompression circuit 55 outputs a 0 level signal,
When the microprocessor 43 monitors the output from the so-called 0 input detection terminal of the D / A converter 56, D
It is confirmed whether the / A converter 56 is operating normally.

The above self-diagnosis is performed by forcibly switching to the self-diagnosis mode at the time of power-on or maintenance, and the diagnosis by the error detection in the demultiplexer 54 is performed at a predetermined cycle even during the normal operation. It may be performed as needed or as needed. Further, the result can be taken out through the input / output terminal 45. In addition,
The microprocessor 43 can exchange data with an external circuit via the input / output terminal 45.

The device with self-diagnosis function according to the present invention is not limited to the first and second embodiments, and for example, an audio signal receiving device provided in a passenger seat of a train or a passenger seat of a bus. The present invention may be applied to a device, an audio signal transmitting device provided in a vehicle such as an aircraft, a train, or a bus. Further, it can be applied to a device that handles a video signal.

[0087]

As described above, the device with self-diagnosis function according to the present invention is a device with self-diagnosis function for performing self-diagnosis for a plurality of built-in circuit blocks. The first self-diagnosis that was performed and the second self-diagnosis that uses a signal dedicated to the test are distinguished, and the first self-diagnosis is performed during normal operation of the device, and the test mode includes when the power of the device is turned on. Since at least the second self-diagnosis is sometimes performed, the self-diagnosis can be performed without using a special jig. Further, an abnormal portion of each circuit block can be detected even while the device is operating.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a first embodiment.

FIG. 2 is a flow chart for explaining a self-diagnosis function in a test mode including power-on of the first embodiment.

FIG. 3 is a flowchart for explaining a self-diagnosis function during normal operation of the first embodiment.

FIG. 4 is a flowchart showing a flow of a self-diagnosis function for each circuit block in a test mode including power-on of the first embodiment.

FIG. 5 is a flowchart showing a flow of a self-diagnosis function for each circuit block in a test mode including power-on of the first embodiment.

FIG. 6 is a flowchart showing a flow of a self-diagnosis function for each circuit block in a test mode including power-on of the first embodiment.

FIG. 7 is a flowchart showing the flow of a self-diagnosis function during normal operation of the first embodiment.

FIG. 8 is a block diagram showing a schematic configuration of a signal transmission system in an aircraft.

9 is a block diagram showing a schematic configuration of a signal transmission side of the signal transmission system shown in FIG.

FIG. 10 is a block diagram showing a schematic configuration of a second embodiment.

[Explanation of symbols]

 3 ... Tuner 4 ... Demodulation circuit 5 ... Demultiplexer 6 ... Expansion circuit 7 ... D / A converter 8 ... Amplifier 9 ..... Microprocessor

Front page continuation (72) Inventor Yasuhiro Hideshima 6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation (72) Inventor Masakatsu Toyoshima 6-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation Shares Company (72) Inventor Masami Yamashita 6-735 Kitashinagawa, Shinagawa-ku, Tokyo Sony Corporation (72) Inventor Tomokazu Wakao 6-735 Kitashinagawa, Shinagawa-ku, Tokyo Sony Corporation Within

Claims (3)

[Claims] 1. An apparatus with a self-diagnosis function for performing self-diagnosis on a plurality of built-in circuit blocks, wherein the self-diagnosis is a first self-diagnosis using check data included in a signal and a signal dedicated to a test. It is distinguished from the second self-diagnosis using the
The self-diagnosis function is performed, and at least the second self-diagnosis is performed in the test mode including the power-on of the device. 2. The signal is previously subjected to error detection coding, and the first self-diagnosis is performed using error detection information obtained by the error detection code in the signal. The device with the self-diagnosis function described. 3. The device with self-diagnosis function according to claim 1, wherein an output signal from the device is muted according to a result of the first self-diagnosis or the second self-diagnosis. .