JPH10290172A - Receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress useless current consumption in the case of recording automatically traffic information. SOLUTION: When a time denoted by a clock circuit 51 reaches a preset time, a power supply of a reception circuit 10 is supplied. Whether or not data are normally received is checked and when the data are normally received as a result of the checking and the data indicate start of a program, a recording and reproducing circuit 30 starts recording of an audio signal of the program. When the data indicate end of the program, the recording and reproducing circuit 30 finishes the recording of audio signals of the program. When the data are not normally received as a result of check, the power supply of the reception circuit 10 is turned off for a prescribed period and then the check is again executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a receiver using, for example, RDS data.

[0002]

2. Description of the Related Art Among FM broadcasting stations in Europe, there are broadcasting stations providing RDS services. This R
In the DS service, data called RDS data is added to an original audio signal for broadcasting. The RDS data is a collection of digital data related to a broadcasting station, a program, and the like. The RDS data includes a PTY code 識別 an identification code indicating the content of the program TA code ‥‥‥ a traffic information announcement identification code TP code識別 Traffic information program identification code AF list が あ る List of alternative frequencies.

[0003] Here, the PTY code is a code indicating the content or type of a program such as news, pops, education, sports, information, etc. in 5 bits. Further, the TA code is data that becomes “1” during the broadcast of traffic information, and the TP code is a code that is set to “1” in the traffic information station. Furthermore, the AF list is a list of frequencies of broadcast stations that are broadcasting the same program as the program currently being received, and has data for up to 25 stations.

Then, the RDS data is subjected to an encoding process for error correction, and the RDS data subjected to the encoding process has a frequency of 57 kHz (this is a value three times the frequency of the stereo pilot signal of 19 kHz). The subcarrier signal is balanced-modulated, and the modulated signal is added to a monaural signal or a stereo composite signal as a main signal and frequency-multiplexed, and the main carrier signal is FM-modulated by the multiplexed signal and transmitted.

[0005] Therefore, in a receiver mounted on an automobile, that is, a so-called car radio, it has been considered to automatically record traffic information by combining RDS data and a timer. That is, when the time set in the timer comes, the power of the car radio is turned on to wait for the broadcast of the traffic information, and when the broadcast of the traffic information is notified by the TA code, the traffic information is recorded.

In this way, when going out by car, for example, the latest traffic information can be obtained in advance.

[0007]

When the traffic information is automatically recorded as described above, the power supply of the car radio is kept on for 2 to 4 hours. In other words, in this case, the traffic information can be reliably recorded, or the traffic information can be recorded two or more times at a later time, so that a change in the traffic condition can be known.

However, when automatically recording traffic information,
Depending on the location of the car, broadcasting may not be normally received at a preset frequency. The car radio consumes about 300 mA of current, depending on the model.

Therefore, at the time when the traffic information is recorded, the car radio generates a relatively large current even though the traffic information cannot be recorded depending on the place where the car is running or parked. May be consumed over several hours.

The present invention is to solve such a problem.

[0011]

Therefore, in the present invention, the main signal is an audio signal of a program for transmitting traffic information, and the main signal is multiplexed with data indicating the start and end of the program. A receiver for receiving the broadcast, a recording / reproducing circuit for recording / reproducing an audio signal, and a circuit for extracting the data from signals output from the receiving circuit,
When the time indicated by the clock circuit reaches a preset time, the power supply of the receiving circuit is turned on, and it is checked whether the data can be normally received. As a result, when the data can be normally read, when the data indicates the start of the program, when the recording and reproduction circuit starts recording the audio signal of the program, and when the data indicates the end of the program, In the recording / reproducing circuit, the recording of the audio signal of the program is terminated, and as a result of the check, when the data cannot be normally received, the power supply of the receiving circuit is turned off for a predetermined period, and then the check is performed again. This is a receiver to be executed. Therefore, when traffic information cannot be received even during the timer period, the power supply of the receiving circuit is turned off and current consumption is suppressed.

[0012]

FIG. 1 shows an example in which the present invention is applied to a car radio. That is, in FIG.
Reference numeral 10 denotes an FM receiving circuit, and a broadcast wave signal received by an antenna 11 is supplied to a tuner circuit 12.
The tuner circuit 12 includes an antenna input circuit to an FM demodulation circuit, is configured in a superheterodyne system, and is configured to perform channel selection by a PLL synthesizer circuit.

Thus, a multiplexed signal of the audio signal (monaural signal or stereo composite signal) and the signal modulated by the RDS data is demodulated and extracted from the tuner circuit 12.

An audio signal of the demodulated output from the tuner circuit 12 is supplied to a low-pass filter 13.
→ Switch circuit 14 → Supplied to the speaker 16 through the signal line of the output amplifier 15.

The demodulated output from the tuner circuit 12 is passed through a bandpass filter 21 to the RDS demodulation circuit 2.
2, the RDS data is demodulated, and the RDS data is supplied to the decoder circuit 23,
The RDS data on which the error correction has been performed is taken out from.

Further, a recording / reproducing circuit 30 for broadcasting audio signals is provided. This recording / playback circuit 30
The car radio shown in FIG. 1 is configured to record and reproduce an audio signal in a semiconductor memory.

That is, the recording / reproducing circuit 30 comprises a memory 31 and a recording / reproducing control circuit 32. The memory 31 is a one-chip IC and has a capacity of, for example, 8 Mbits. The control circuit 32 is also a one-chip IC.
It has an A / D converter, an ADPCM encoder and decoder, a D / A converter, an address controller, and the like.

In the recording mode, the control circuit 32 converts the audio signal from the low-pass filter 13 into digital audio data by A / D conversion and then compresses the data by the ADPCM method. It is written to. In the reproduction mode, the data written in the memory 31 is sequentially read out by the control circuit 32.
The data is expanded to the original digital audio data and then D / A converted to the original analog audio signal.
This analog signal is supplied to the switch circuit 14.

In this case, the mode in which data is written to the memory 31 is an additional mode in which writing is started from the address next to the last address of the previous writing.
Further, when writing has progressed to the last address of the memory 31, writing is performed again from the first address.

As an example, the sampling frequency at the time of A / D conversion is 5.3 MHz / 1024, and the bit length after ADPCM is 3 bits. Therefore, the memory 31
The recording time is 8 Mbits / (5.3 MHz / 1024 ×
(3 bits) = approximately 528 seconds, which means that a total of nearly 9 minutes can be recorded.

Further, in this example, the tuning of the tuner circuit 12 and the processing of the recording / reproducing circuit 30 are controlled by the microcomputer 40. The microcomputer 40 includes a CPU 41, a ROM 42 in which various processing routines are written, and a RAM 4 for a work area.
3. It has input / output ports 44 to 46 and a key interface circuit 47. These circuits 42 to 47 are connected to the CPU 41 through a system bus 49.

In this case, the ROM 42 stores the automatic recording routine 10 shown in FIG.
Has zero. The details of the routine 100 will be described later, but FIG. 2 shows only parts related to the present invention for simplicity.

The port 44 is connected to the tuner circuit 12, and data specifying the reception frequency is supplied from the CPU 41 to the tuner circuit 12 through the port 44, thereby performing tuning. Further, the RDS data from the decoder circuit 23 is taken into the CPU 41 through the port 45.
The control signal is supplied from the port 46 to the switch circuit 14, and the muting signal is supplied from the port 46 to the amplifier 15. Further, various operation keys (operation switches) 48 such as a channel selection key are connected to the interface circuit 47.

A clock circuit 51 and a display control circuit 52 are connected to the bus 49. And the clock circuit 51
, The current time is measured, and data of the current time is supplied to the bus 51. The display control circuit 52 is connected to, for example, an LCD 53 as a display element. When predetermined character data is supplied to the display control circuit 52, characters (including numbers and symbols) corresponding to the character data are displayed on the LCD 53. Is displayed.

Further, although not shown, the microcomputer 40 is always supplied with power (for example, even if the car key is removed), and the power supply of the receiving circuit 10 is
The microcomputer 40 is configured to be on / off controlled.

According to such a configuration, when the power of the car radio is turned off, the power of the receiving circuit 10 is turned off and the microcomputer 40 is in the standby mode with low power consumption. The microcomputer 40 is in a state in which the microcomputer 40 measures the time of the clock circuit 51 and only responds to the input of the key 48 during the TKI in the standby mode. Therefore, when the power is off, the microcomputer 40 is slightly
It only consumes about A current.

However, when a key operation for turning on the power is performed on the key 48, the microcomputer 40 enters a normal operation mode and the power supply of the receiving circuit 10 is turned on.

When a key related to channel selection is operated with respect to the key 48, data for specifying a reception frequency is supplied from the CPU 41 to the tuner circuit 12 through the port 44, and a broadcasting station corresponding to the key operation is selected. . At this time, the switch circuit 14 is connected to the state shown in FIG.
Muting is turned off. Therefore, the broadcast of the broadcast station selected by the key operation can be heard through the speaker 16.

At this time, the broadcasting station receiving the signal is R
In the case of a broadcasting station providing a DS service, RDS data is output from the decoder circuit 23 and supplied to the port 45. As a result, the LCD 53 displays
At that time, the name of the broadcasting station being received is displayed.

Further, when performing automatic recording of traffic information, a broadcasting station for broadcasting the traffic information is selected by the key 48 in advance. Further, the start time of the timer and the start time of the automatic infrared recording are set by the key 48 in advance. For example, if traffic information broadcasted between 5:00 am and 9:00 am is to be recorded, the start time "5:00 am" is set. In this example, the end time is automatically set to four hours after the start time, so that "9:00 am" of the end time need not be set. Further, execution of automatic recording of the traffic information is instructed by the key 48.

Then, the data specifying the reception frequency of the broadcasting station input by the key and the data of the start time of the automatic recording are stored in the RAM 43, and a flag indicating the request for the automatic recording of the traffic information is stored in the RAM 43. Will be saved.

The automatic recording of traffic information is performed by the CPU 4
1 executes the routine 100 to perform the following. That is, when the power is off, the clock circuit 51
For example, the processing of the CPU 41 starts from step 101 of the routine 100 every five minutes, and the microcomputer 40 enters the normal operation mode. Then, in step 102, the current time measured by the clock circuit 51 is stored in the RAM 43. It is checked whether it is the start time of the automatic recording saved in the. If not, the processing from step 102 to step 132
In this step 132, the microcomputer 40 enters the standby mode and ends the routine 100.

However, if the current time measured by the clock circuit 51 is the start time of the automatic recording stored in the RAM 43 in step 102, the process proceeds from step 102 to step 103. Then, in step 103, by checking the flag stored in the RAM 43, it is checked whether or not the automatic recording of traffic information is requested.
The routine proceeds to 2 and the routine 100 ends.

Further, if it is determined in step 103 that automatic recording of traffic information is requested, the process proceeds from step 103 to step 111.
At 1, the power supply of the receiving circuit 10 is turned on, and the muting of the amplifier 15 is turned on. Subsequently, in step 112, the data designating the reception frequency stored in the RAM 43 is supplied to the tuner circuit 12, so that a broadcasting station where traffic information is to be recorded is selected.

Next, the process proceeds to step 113 where the TP code of the RDS data output from the decoder circuit 23 is checked to determine whether or not the traffic information station can be normally received at the frequency set in step 112. Checked. Then, when the signal can be received normally, the process proceeds from step 113 to step 120,
In step 120, traffic information is recorded according to the TA code of the RDS data output from the decoder circuit 23.

That is, in step 120, even when the TA code is "0" even within four hours from the start time checked in step 102, the recording / reproducing circuit 30 is in the standby mode.

When the TA code becomes "1" in the standby mode, a command for instructing recording is supplied from the CPU 41 to the control circuit 32.
Becomes the recording mode. Then, in this recording mode, the audio signal from the low-pass filter 13, that is,
In this case, the audio signal carrying the traffic information is written into the memory 31 after being subjected to A / D conversion and data compression as described above. That is, traffic information is recorded.

When the traffic information is completed,
When the TA code becomes "0", when the TA code becomes "0", a command for instructing standby is supplied from the CPU 41 to the control circuit 32, and the recording / reproducing circuit 30 returns to the standby mode.

Thus, if the TA code becomes "1" within four hours from the start time checked in step 102, the traffic information at that time is recorded in the recording / reproducing circuit 30.

When four hours have passed from the start time checked in step 102, (in this case, if the recording mode is set, the recording mode is canceled) and step 12 is executed.
0, and then in step 131, the receiving circuit 10
Is turned off, and then the routine 100 is ended in step 132.

As described above, according to step 120, when the TA code is "1", the traffic information at that time is recorded in the recording / reproducing circuit 30.

On the other hand, if it is determined in step 113 that the broadcast cannot be received normally as a traffic information station at the frequency set in step 112, the process proceeds to step 11
3 to step 114. And this step 1
At 14, a traffic information station of an alternative frequency is selected by referring to the AF list.
It is checked whether the received frequency of the tuner circuit 12 has made one round of the alternative frequency in the AF list.

If it has not completed one round, the process returns from step 115 to step 113, and the reception state is checked again. Therefore, steps 113-1
According to No. 15, a broadcasting station designated in advance or a broadcasting station of an alternative frequency thereof is selected, and step 120
Records traffic information.

However, if the broadcast cannot be received normally by any of the alternative frequency broadcast stations, the tuner circuit 12 determines in step 115 that the reception frequency of the tuner circuit 12 is AF
It goes around the alternative frequency of the list once. Then, the process proceeds from step 115 to step 116, in which the power supply of the receiving circuit 10 is turned off,
Thereafter, in step 117, a waiting time of, for example, 5 minutes is performed.

After the elapse of 5 minutes, the process returns from step 117 to step 111, and returns to step 111.
The following is executed again.

Then, as described above, the recording / reproducing circuit 3
When traffic information is recorded at 0, when the power supply is turned on and one of the keys 48 is operated to instruct reproduction, the switch circuit 1 is controlled by a control signal from the port 46.
4 is connected in a state opposite to that shown in the figure. Also, a command for instructing reproduction is supplied from the CPU 41 to the control circuit 32,
The digital audio data written in the memory 31 is sequentially read.

Then, the read digital audio data is subjected to data expansion and D / A conversion to obtain an original analog audio signal, that is, an audio signal indicating traffic information. The signal is supplied to the speaker 16 through the circuit 14 and the amplifier 15. Therefore, the user can use the memory 3
1. You can listen to the traffic information recorded digitally.

During the reproduction, when one of the keys 48 is instructed to stop, the switch circuit 14 is connected to the state shown in the figure by a control signal from the port 46. Further, a command instructing termination of reading is supplied from the CPU 41 to the control circuit 32. As a result, the memory 31
Is not performed, and the reproduction of the traffic information ends.

Thus, according to this FM receiver, when traffic information is broadcast during the time period set by the timer, this is automatically recorded in the memory 31. In particular, in the above-mentioned FM receiver, the reception state When the traffic information cannot be received normally due to poor communication, the power of the receiving circuit 10 is turned off for, for example, 5 minutes, and then the recording of the traffic information is attempted again, so that the car battery is not wasted. .

In addition, the configuration for this need only be changed from the automatic recording routine to the routine 100, that is, it can be handled only by software, and there is no need to add or change hardware.

In the above description, the audio signal of the traffic information is digitally recorded / reproduced in the memory 31. However, the recording / reproducing medium may be another medium, and the recording / reproducing circuit 30 also corresponds to the medium. Change it.

[0052]

According to the present invention, when traffic information is broadcast during the period set by the timer, the traffic information is automatically recorded. In addition, when the reception information is poor and the traffic information cannot be received normally, the power of the receiving circuit is turned off for a predetermined period, and then the recording of the traffic information is attempted again, so that the battery is wasted. There is no. Moreover,
The configuration for that only needs to change the processing routine, and there is no need to add or change hardware.

[Brief description of the drawings]

FIG. 1 is a system diagram illustrating one embodiment of the present invention.

FIG. 2 is a flowchart illustrating one embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... FM reception circuit, 12 ... Tuner circuit, 13 ... Low-pass filter, 16 ... Speaker, 21 ... Band-pass filter, 22 ... RDS demodulation circuit, 23 ... Decoder circuit, 3
0: recording / reproducing circuit, 31: semiconductor memory, 32: recording / reproducing control circuit, 40: microcomputer, 41: CP
U, 100 ... Automatic recording routine

Claims (3)

[Claims] 1. A broadcast receiver in which a main signal is an audio signal of a program for transmitting traffic information, and data indicating the start and end of the program are multiplexed on the main signal and broadcast. Receiving circuit, a recording / reproducing circuit for recording / reproducing an audio signal, a circuit for extracting the data from signals output from the receiving circuit, and a clock circuit, and a time indicated by the clock circuit. When a predetermined time comes, the power of the receiving circuit is turned on, and it is checked whether the data can be normally received. As a result of the check, when the data can be normally received, the data is When indicating the start of the program, the recording / reproduction circuit starts recording the audio signal of the program, and the data indicates the end of the program. In the recording / reproducing circuit, the recording of the audio signal of the program is terminated, and as a result of the check, when the data cannot be normally received, the power supply of the receiving circuit is turned off for a predetermined period. Receiver to try again. 2. The receiver according to claim 1, wherein the data is data in an RDS service. 3. The receiver according to claim 2, wherein the receiving circuit is a car radio receiving circuit.