JP2010028393A - Receiver - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a receiver that not only reduces execution time of processing according to a command but also mitigates load of a system microcomputer. <P>SOLUTION: The receiver includes a data generating portion that generates not only an audio signal in response to an output from a tuner for receiving a broadcasting signal broadcast from a radio station but also receiving strength data for indicating the receiving strength of the broadcasting signal, an audio signal processing portion for processing the audio signal based on predetermined data for output, and a control portion for carrying out in parallel at least either of acquisition of the receiving strength data and setting of the predetermined data based on indicative data serially input for indicating at least either of the acquisition of the receiving strength data and the setting of the predetermined data. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a receiving apparatus.

  In an electronic device such as a car stereo, a system microcomputer is generally used to control a CD (Compact Disc) player, a radio receiver, a display, and the like. Radio receivers include, for example, receivers compatible with RDS (Radio Data System) in Europe and RBDS (Radio Broadcasting Data System) in the United States.

For example, in the case of RDS, alternative station data indicating the frequency of an alternative station that is broadcasting the same program is superimposed on the broadcast signal. The RDS receiver that receives the RDS broadcast signal detects the reception level of the alternative station by switching from the broadcast station designated by the user to the alternative station based on the alternative station data, for example, every predetermined period. A process of returning the station to the original broadcasting station is performed. When the receiving station is switched to an alternative station, the audio signal of the RDS receiver is generally muted in order to reduce the uncomfortable feeling of the reproduced sound. Also, when returning the receiving station to the original state, the mute is released. A series of processes for detecting the reception level of the above-mentioned alternative station is executed by transmitting a command corresponding to each process to the RDS receiver at an appropriate timing by the system microcomputer (for example, Patent Document 1). reference).
JP 2005-198092 A

  Communication between the RDS receiver and the system microcomputer is generally executed serially in order to reduce the mounting area of the RDS receiver and the system microcomputer. Therefore, for example, when the RDS receiver executes a series of processes for detecting the reception level of the alternative station as described above, the RDS receiver receives each of the commands corresponding to the processing contents serially, The station reception level is transmitted serially. For this reason, it takes a long time for the RDS receiver to execute a series of processes. In addition, since the system microcomputer needs to appropriately transmit a command corresponding to the processing content to the RDS receiver, a load is applied to the system microcomputer.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a receiving apparatus that can reduce the execution time of processing according to a command and can reduce the load on a system microcomputer.

  In order to achieve the above object, a receiving apparatus according to one aspect of the present invention generates an audio signal according to an output from a tuner that receives a broadcast signal broadcast from a radio station, and receives the broadcast signal. A data generation unit that generates reception intensity data indicating intensity; an audio signal processing unit that outputs the audio signal by performing processing based on setting data; and acquisition of the reception intensity data and setting of the setting data A control unit that executes at least one of obtaining the received intensity data and setting the setting data in parallel based on instruction data serially input to instruct at least one of them.

  It is possible to provide a radio receiver capable of reducing the execution time of processing according to a command and reducing the load on the system microcomputer.

At least the following matters will become apparent from the description of the present specification and the accompanying drawings.
FIG. 1 is a diagram showing a configuration of an RDS receiver 10 (receiving apparatus) according to an embodiment of the present invention. The RDS receiver is a radio receiver that can receive and reproduce an RDS broadcast signal, and includes an antenna 20, a tuner 21, and a system LSI (Large Scale Integration) 22. Also, the RDS receiver of this embodiment is provided in a car stereo (not shown).

  The tuner 21 is a circuit that generates an intermediate frequency (IF) signal from a broadcast signal received via the antenna 20 based on frequency data set in the frequency setting unit 32. The tuner 21 includes a mixer 30, a PLL (Phase Locked Loop) 31, and a frequency setting unit 32.

  The mixer (MIX) 30 is a circuit that generates an IF signal by down-converting a broadcast signal received by the antenna 20 with an oscillation signal output from the PLL 31.

  The PLL 31 is a circuit that generates an oscillation signal having an oscillation frequency based on the frequency data set in the frequency setting unit 32.

  The frequency setting unit 32 is a circuit that holds the frequency data output from the system LSI 22 and sets the oscillation frequency of the PLL 31 based on the frequency data. Note that the frequency setting unit 32 of the present embodiment is realized by a register, for example.

  The system LSI 22 is a circuit for reproducing sound in accordance with an IF signal output from the tuner 21 or an audio signal IN output from a car stereo CD player (not shown) based on an instruction from the system microcomputer 23. It is. Further, the system LSI 22 transmits RDS data indicating the content of the broadcast signal and reception intensity data indicating the reception intensity of the broadcast signal to the system microcomputer 23 based on an instruction from the system microcomputer 23. The system LSI 22 of this embodiment includes DSPs (Digital Signal Processors) 40 and 41, an address decoder 42, a microcomputer 43, and a parallel bus 44.

  The DSP 40 (data generation unit) generates a digital audio signal from the input IF signal and outputs it to the DSP 41, and outputs RDS data and received intensity data to the microcomputer 43. The DSP 40 includes an AD converter (ADC) 50, an IF processing unit 51, a level detection unit 52, an RDS demodulation unit 53, and a first setting unit 54.

  The AD converter 50 converts an input analog IF signal into a digital IF signal. The IF processing unit 51 performs a detection process on the digital IF signal to generate a digital audio signal. Based on the output of the IF processing unit 51, the level detection unit 52 generates reception intensity data indicating the reception intensity of a broadcast signal such as an S meter DC value, an S meter AC value, and an adjacent disturbance level. The reception intensity data generated by the level detection unit 52 is stored in the storage unit 55 included in the level detection unit 52. Note that the storage unit 55 in the present embodiment is realized by a register, for example. The RDS demodulator 53 generates RDS data based on the output of the IF processor 51. Similarly to the level detection unit 52, the RDS demodulation unit 53 of the present embodiment is also configured to include a storage unit 56 that stores the generated RDS data. The first setting unit 54 holds the first setting data output from the microcomputer 43 and sets the operation states of the level detection unit 52 and the RDS demodulation unit 53. Specifically, based on the first setting data, it is set whether or not the level detection unit 52 generates reception intensity data, and the RDS demodulation unit 53 is set whether or not to generate each of RDS data. Note that the first setting unit 54 of the present embodiment is realized by a register, for example. The storage unit 55 corresponds to the storage unit of the present invention.

  The DSP 41 (audio signal processing unit) reproduces the digital audio signal from the DSP 40 or the analog audio signal IN from the CD player by performing processing based on the second setting data held in the second setting unit 65. To do. The DSP 41 includes an AD converter 60, a selection unit 61, an equalizer (EQ) 62, a mute unit 63, a DA converter (DAC) 64, and a second setting unit 65. The second setting data corresponds to the setting data of the present invention.

  The AD converter 60 converts the analog audio signal IN from the CD player into a digital audio signal. The selection unit 61 selects either the digital audio signal from the DSP 40 or the digital audio signal from the AD converter 60 based on the second setting data held in the second setting unit, and the equalizer 62 Output to. The selection unit 61 is realized by a selector circuit, for example. The equalizer 62 emphasizes or attenuates a specific frequency band of the input digital audio signal based on the second setting data. The mute unit 63 controls mute for the digital audio signal from the equalizer 62 based on the second setting data. The DA converter 64 converts the digital audio signal output from the mute unit into an analog audio signal, and outputs the analog audio signal for reproduction by a car stereo speaker (not shown). The second setting unit 65 holds the second setting data output from the microcomputer 43, and sets the states of the selection unit 61, the equalizer 62, and the mute unit 63 as described above. The second setting unit 65 is realized by a register, for example.

  The address decoder 42 selects one of the first setting unit 54, the storage units 55 and 56, and the second setting unit 65 according to the address data output in parallel from the microcomputer 43. That is, the address decoder 42 decodes the address data and designates the access destination of the microcomputer 43.

  The microcomputer 43 (control unit) is built in the system LSI 22 and controls the system LSI 22 based on a command input from the system microcomputer 23. For example, the microcomputer 43 sets the reception frequency of the tuner 21 and the contents of processing in each of the DSPs 40 and 41. The microcomputer 43 includes a decoder 70 and a data control unit 71.

  The decoder 70 decodes the command input from the system microcomputer 23 and outputs the decoding result to the data control unit 71. Specifically, the decoder 70 determines whether it is necessary to access each of the frequency setting unit 32, the first setting unit 54, the storage units 55 and 56, and the second setting unit 65 based on the input command. The decoding result shown is generated. In the present embodiment, based on the logic level of the flag included in the command, for example, second setting data including selection of an input signal of the selection unit 61 and execution of processing of the mute 63 is generated. To do.

  The data control unit 71 sets data in each of the frequency setting unit 32, the first setting unit 54, and the second setting unit 65 based on the decoding result of the command, and is stored in each of the storage units 55 and 56. Intensity data and RDS data are acquired. Further, the data control unit 71 transmits the acquired reception intensity data and RDS data to the system microcomputer 23. In the present embodiment, the microcomputer 43 and the tuner 21 are connected by a serial bus, and the data control unit 71 is realized by the microcomputer 43 executing a program.

  The parallel bus 44 includes a parallel address bus 80 that connects the address decoder 42 and the microcomputer 43, and a parallel data bus 81 that connects the DSPs 40 and 41 and the microcomputer 43. Note that, for example, address data for accessing the first setting unit 54, the storage units 55 and 56, and the second setting unit 65 is output from the data control unit 71 to the address bus 80. For example, the first setting data and the second setting data for the first setting unit 54 and the second setting unit 65 are output from the data control unit 71 to the data bus 81. Further, for example, reception intensity data and RDS data from the storage units 55 and 56 are output to the data bus 81.

  The system microcomputer 23 controls the entire car stereo. For example, the system microcomputer 23 outputs a command for changing the receiving station to the microcomputer 43 in response to the user's operation for changing the receiving station. Further, for example, RDS data from the microcomputer 43 is received. The RDS data includes, for example, information on the broadcast content of the receiving station and information on an alternative station that is broadcasting the same broadcast content as the receiving station. Therefore, the system microcomputer 23 periodically transmits a command for acquiring the reception intensity of the broadcast signal of the alternative station to the microcomputer 43 based on the RDS data. When the reception sensitivity of the alternative station is better than that of the reception station selected by the user, a command for switching from the reception station to the alternative station is transmitted to the microcomputer 43.

  Here, the operation of the RDS receiver 10 when the system microcomputer 23 transmits a command for acquiring the reception intensity of the alternative station to the microcomputer 43 will be described with reference to the flowchart shown in FIG. Here, in the RDS receiver 10, the frequency setting unit 32 of the tuner 21, the first setting unit 54, and the second setting unit 65 of the system LSI 22 are set so that the received broadcast signal can be reproduced. And Further, it is assumed that the system microcomputer 23 receives the RDS data and acquires information on the alternative station.

  The decoder 70 of the microcomputer 43 receives from the system microcomputer 23 a command for acquiring the reception intensity of the alternative station (hereinafter referred to as an alternative station search command) (S100). The decoder 70 decodes the alternative station search command and outputs the decoding result to the data control unit 71 (S101). Based on the decoding result, the data control unit 71 performs a mute process of the audio signal in order to reduce the uncomfortable feeling of the reproduced sound. Specifically, the data control unit 71 transmits address data for the second setting unit 65 to the address decoder 42 via the address bus 80. Then, the data control unit 71 sets data such that mute processing is performed on the audio signal as second setting data in the second setting unit 65 via the data bus 81 (S102). In this embodiment, when the data control unit 71 sets data, the data is set after the access destination address is transmitted, as in the case described in step S101. Therefore, hereinafter, in the present embodiment, it is assumed that when the data control unit 71 sets data, the address data of the access destination is transmitted in advance by the data control unit 71. Further, hereinafter, the data control unit 71 executes processing based on the decoding result of the alternative station search command.

  When the data control unit 71 executes the mute processing of the audio signal from the DSP 41, the data control unit 71 changes the reception frequency of the tuner 21 so that the broadcast signal of the alternative station can be received. Specifically, the data control unit 71 serially sets the frequency data of the alternative station in the frequency setting unit 32 (S103). Then, the data control unit 71 operates the level detection unit 52 to detect the strength of the broadcast signal of the alternative station. Specifically, the data control unit 71 sets data for operating the level detection unit 52 in the first setting unit 54 as first setting data (S104). The reception intensity data of the alternative station is stored in the storage unit 55 of the level detection unit 52. The data control unit 71 outputs the address data of the storage unit 55 to the address decoder 42 in order to access the storage unit 55 and acquire the reception intensity data of the alternative station. As a result, the reception intensity data of the alternative station stored in the storage unit 55 is output to the data bus 81, and the data control unit 71 acquires the reception intensity data (S105). The data control unit 71 changes the reception frequency of the tuner 21 in order to return from the alternative station to the original receiving station. Specifically, the data control unit 71 sets the frequency data of the reception frequency of the original receiving station in the frequency setting unit 32 (S106). In addition, the data control unit 71 sets data that stops the operation of the level detection unit 52 in the first setting unit 54 as first setting data (S107). The data control unit 71 cancels the mute process in order to reproduce the sound of the original receiving station. Specifically, the data control unit 71 sets data such that the mute process is released as second setting data in the second setting unit 65 (S108). The data control unit 71 serially transmits the acquired reception intensity data of the alternative station to the system microcomputer 23 (S109).

  In the RDS receiver 10 of the present embodiment configured as described above, when the microcomputer 43 provided in the system LSI 22 serially receives the substitute station search command from the system microcomputer 23 (S100), the mute process is executed. (S102) is executed in parallel, and the reception intensity data in the alternative station is acquired in parallel (S105). Then, the microcomputer 43 releases the mute in parallel (S108), and finally transmits the received intensity data serially to the system microcomputer 23 (S109). In the present embodiment, when the mute processing state is updated, all of the second setting data is updated. Further, as described above, since the reception intensity data is data such as S meter DC, S meter AC, and adjacent interference level, the data size generally increases. Therefore, for example, the processing time can be shortened as compared to the execution of mute processing and the case where the system microcomputer 23 directly acquires the received intensity data serially. For this reason, since the mute period can be shortened, it is possible to reduce the uncomfortable feeling of the reproduced sound that occurs when the reception intensity data of the alternative station is acquired. Furthermore, in the present embodiment, the system microcomputer 23 accesses the microcomputer 43 in order to acquire alternative station data in two cases: when transmitting a command (S100) and when acquiring received intensity data (S109). Times. Therefore, it is possible to reduce the load on the system microcomputer 23 by using the RDS receiver 10 of the present embodiment.

  Further, when receiving the alternative station search command (S100), the microcomputer 43 of the present embodiment changes the reception frequency of the tuner 21 to the frequency of the alternative station (S103), and further performs processing to return to the original frequency of the receiving station. Execute (S106). In general, since the system microcomputer 23 performs overall control of the entire car stereo, for example, when an interrupt from a CD player or the like occurs, there is a case where the reception frequency of the tuner 21 cannot be changed immediately. In this embodiment, since the system microcomputer 23 does not need to directly control the tuner 21, it is not necessary to consider the interruption of the system microcomputer 23 described above when executing the alternative station search command. Therefore, the RDS receiver 10 of the present embodiment can reduce the execution time of processing according to the command and reduce the load on the system microcomputer 23.

  In addition, when the microcomputer 43 of the present embodiment receives the alternative station search command (S100), the decoder 70 decodes the alternative station search command (S101). Furthermore, in the present embodiment, the data control unit 71 performs setting of each of the frequency data, the first setting data, and the second setting data, and acquisition of the reception intensity data based on the decoding result (S102). To S108). As described above, the decoder 70 of this embodiment needs to access each of the frequency setting unit 32, the first setting unit 54, the storage units 55 and 56, and the second setting unit 65 based on the input command. A decoding result indicating whether or not there is generated is generated. Therefore, for example, when acquiring only the reception intensity data of the receiving station designated by the user, the decoder 70 generates a decoding result indicating that only the storage unit 55 needs to be accessed. Therefore, the data control unit 71 only needs to access the storage unit 55 based on the decoding result, and the command processing time can be shortened. Further, for example, compared to the case where the decoder 70 is not used, the RDS receiver 10 can be controlled while suppressing the data size of the command transmitted by the system microcomputer 23, so that the load on the system microcomputer 23 is reduced. it can.

  In addition, the said Example is for making an understanding of this invention easy, and is not for limiting and interpreting this invention. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes equivalents thereof.

  In this embodiment, when acquiring the reception strength of the alternative station, first, the data control unit 71 executes the mute process (S102), and the data processing control unit 71 changes the reception frequency of the tuner 21. (S103) It is not limited to that. For example, when the time until the IF signal from the tuner 21 reaches the mute unit 63, that is, when the delay time of the IF signal in the system LSI 22 is longer than the time for setting the mute processing, first, the data processing control unit 71 The reception frequency of the tuner 21 may be changed and then the mute process may be executed.

  In addition, for example, reception intensity data and RDS data are output to the data bus 81 in the present embodiment, but the present invention is not limited thereto. For example, when the system microcomputer 23 checks the state of the mute unit 63, the mute unit 63 generates data indicating the mute state, and the system microcomputer 23 performs the mute operation via the data bus 81 and the data control unit 71. Get status data. That is, data relating to blocks included in the system LSI 22 is output from the respective blocks to the data bus 81 of the present embodiment.

It is a figure which shows the structure of the RDS receiver which is one Embodiment of this invention. It is a figure which shows an example of the process which acquires the reception intensity | strength of an alternative station.

Explanation of symbols

10 RDS receiver 20 Antenna 21 Tuner 22 System LSI
23 System microcomputer 30 Mixer (MIX)
31 PLL
32 Frequency setting part 40, 41 DSP
42 Address decoder 43 Microcomputer 44 Parallel bus 50, 60 AD converter (ADC)
51 IF Processing Unit 52 Level Detection Unit 53 RDS Demodulation Unit 54 First Setting Unit 55, 56 Storage Unit 61 Selection Unit 62 Equalizer (EQ)
63 Mute section 64 DA converter (DAC)
65 Second setting unit 70 Decoder 71 Data control unit 80 Address bus 81 Data bus

Claims (3)

A data generation unit that generates an audio signal according to an output from a tuner that receives a broadcast signal broadcast from a radio station, and generates reception intensity data indicating the reception intensity of the broadcast signal;
An audio signal processing unit that performs processing based on setting data and outputs the audio signal;
Based on instruction data serially input to instruct at least one of acquisition of the reception intensity data and setting of the setting data, at least one of acquisition of the reception intensity data and setting of the setting data A control unit that executes in parallel;
A receiving apparatus comprising: The audio signal processing circuit according to claim 1,
The instruction data is
Including data for setting the receiving frequency of the tuner;
The controller is
Setting frequency data for setting the reception frequency of the tuner in the tuner based on the instruction data;
A receiving device. The audio signal processing circuit according to claim 2,
The data generator is
A storage unit for storing the received intensity data;
The controller is
A decoder that decodes the instruction data and generates a decoding result indicating whether or not the address data specifying the storage unit is output and whether or not the setting data and the frequency data are set;
A data control unit that executes processing according to the decoding result among the output of the address data and the setting data and the setting of the frequency data,
A receiving apparatus comprising:

Images