Summary of the invention
The object of the invention is to overcome the deficiencies in the prior art, provide a kind of by the system and method for earphone socket swap data, it only needs to connect by a tone frequency channel wire, easy to operate, can realize reliable communication by earphone socket, wide accommodation, cost is low, safe and reliable.
According to technical scheme provided by the invention, the described system of earphone socket swap data of passing through, comprises equipment to be controlled, and described equipment to be controlled is connected with the audio frequency apparatus in main control system by audio cable; Main control system, equipment to be controlled all can will be treated that communication data is modulated into sound signal, and carry out the exchange of sound signal by audio cable and audio frequency apparatus.
Described main control system comprises the host data modular converter being connected with audio frequency apparatus and the configuration application module being connected with described host data modular converter;
Configuration application module, be connected with host data modular converter, data to be communicated by letter are formed to main frame and send communication data packet, and described main frame transmission communication data packet is transferred in host data modular converter, to be converted to main frame by host data modular converter, send sound signal, and can carry out dissection process to the equipment transmission communication data of host data modular converter transmission;
Host data modular converter, the packet that configuration application module is sent converts main frame to and sends sound signal, and the equipment transmission sound signal that audio frequency apparatus can be received converts the required main frame received communication data of configuration application module to;
Audio-frequency module, the main frame of host data modular converter transmission is sent to sound signal and carry out playback output, and the equipment that can obtain device transmission to be controlled by audio cable sends sound signal, and equipment is sent to sound signal by host data modular converter, be converted to main frame received communication data.
Described host data modular converter comprises that main frame sends data-switching portion and host receiving data converter section; Described main frame sends data-switching portion and comprises the main frame parallel serial conversion module that carries out parallel-serial conversion for main frame being sent to communication data packet, described main frame parallel serial conversion module with for Data Modulation being become the main frame sound signal modulation module of sound signal be connected;
Described host receiving data converter section comprises main frame zero-crossing detector, and the output terminal of main frame zero-crossing detector is connected along counter with main frame 0/1, and main frame 0/1 is connected with main frame string modular converter by main frame frequency judgement/detuner along counter; Main frame frequency judgement/detuner, main frame sound signal modulation module are all connected with the output terminal of main frame baud rate controller.
Described main frame sound signal modulation module comprises main frame DDS signal generator or main frame square wave signal generator, and described main frame square wave signal generator obtains the square-wave signal of generation after by the filtering of main frame wave digital lowpass filter main frame and sends sound signal.
Described equipment to be controlled comprises
Filtering processing module, is connected with audio cable and device data modular converter, can send sound signal to the equipment of the main frame transmission sound signal of audio cable transmission and the transmission of device data modular converter and carry out filtering;
Device data modular converter, be connected with filtering processing module and microprocessor applications module, the main frame of filtering processing module transmission can be sent to sound signal and convert the required equipment received communication data of microprocessor applications module to, and the equipment sending data of microprocessor applications module transmission can be converted to equipment transmission sound signal.
Described device data modular converter comprises equipment input signal modular converter, apparatus output signal modular converter and equipment baud rate controller, and (and apparatus output signal modular converter is connected described equipment baud rate controller with equipment input signal modular converter.
Described equipment input signal modular converter adopts the first input signal modular converter or the second input signal modular converter;
The first input signal modular converter comprises that the main frame for the processing module transmission that accepts filter sends device A/D modular converter of sound signal and the equipment zero-crossing detector being connected with device A/D modular converter; Described equipment zero-crossing detector is connected along counter with equipment 0/1, and described equipment 0/1 is connected with device frequency judgement/detuner along counter, and device frequency judgement/detuner and equipment string modular converter and equipment baud rate controller are connected;
The second input signal modular converter comprises that the main frame for the processing module transmission that accepts filter sends the comparison in equipment device of sound signal and the grabber being connected with comparison in equipment device output terminal, described grabber is connected with pulsewidth/frequency computation part module, pulsewidth/frequency computation part module is connected with detuner, and described detuner and equipment baud rate controller and equipment string modular converter are connected.
Described apparatus output signal modular converter adopts the first output signal modular converter, the second output signal modular converter or the 3rd output signal modular converter;
The first output signal modular converter comprises equipment parallel serial conversion module, and described equipment parallel serial conversion module is connected with equipment DDS signal generator, and described equipment DDS signal generator is connected with equipment baud rate controller and equipment D/A modular converter;
The second output signal modular converter comprises equipment parallel serial conversion module and the equipment square wave signal generator being connected with described equipment the module of going here and there; Described equipment square wave signal generator is connected with equipment baud rate controller and apparatus figure low-pass filter, and described apparatus figure low-pass filter is connected with equipment D/A modular converter;
The 3rd output signal modular converter comprises equipment parallel serial conversion module and the PWM module being connected with described equipment parallel serial conversion module, and described PWM module is connected with equipment baud rate controller.
By a method for earphone socket swap data, comprise equipment to be controlled, described equipment to be controlled is connected with the audio frequency apparatus in main control system by audio cable; Main control system, equipment to be controlled all can will be treated that communication data is modulated into sound signal, and carry out the exchange of sound signal by audio cable and audio frequency apparatus.
Described main control system, equipment to be controlled comprise FSK modulation or ASK modulation by the method for the treatment of communication data audio signal modulation.
Advantage of the present invention: connect by audio cable between equipment and control main frame to be controlled, in equipment to be controlled, main control system, modulate, the operation of demodulation, data to be communicated by letter can be exchanged with voice-frequency signalling, thereby can obtain the duty of equipment to be controlled or treat opertaing device, control effectively, whole system only comprises a small amount of peripheral circuit, and cost is low, only by audio cable, connects, easy to use, simple and reliable.
Embodiment
Below in conjunction with concrete drawings and Examples, the invention will be further described.
As shown in Figure 1: be the schematic diagram of existing employing serial communication, main equipment is communicated by letter with equipment connection to be controlled by RS232 serial ports.Although utilize RS232 serial ports to communicate, send and control data, fetch equipment state is very convenient, and simple.But the mobile device outsides such as the computer equipment of new production at present and mobile phone do not provide serial ports such interface; And common serial interface is bulky, extremely take the space of equipment; If use special-purpose miniature connector, can cause interface disunity again, be inconvenient to use.Therefore adopt the mode of serial ports swap data, in the application of Smart Home, cannot meet the demands.
As shown in Figure 2, be the schematic diagram that existing employing earphone socket communicates, be similar to the card reader of mobile phone.Be that mobile phone or panel computer utilize earphone socket to be transferred to signaling conversion circuit data, and can utilize signaling conversion circuit to extract data, and give equipment to be controlled.But signaling conversion circuit need to be used special chip, in signaling conversion circuit, comprise modulation-demodulation circuit, and additionally used modulation-demodulation circuit to be used for doing signal conversion, the scope of application is less, and cost is higher.Also cannot use in the application of Smart Home simultaneously.
As shown in Figure 3, be the schematic diagram communicating by loudspeaker, pass through Data Modulation, to sound, to utilize loudspeaker to transfer out, by the microphone of communication facilities, received after data, carry out signal conversion, extract data, then give controlled equipment.This embodiment can only realize one-way communication, and by after loudspeaker signal transmission, can introduce ground unrest, and the extraction of the processing of signal and data has been proposed to requirements at the higher level, and controlled device one-piece construction can be more complicated like this, and cost also can be higher.
In addition, by earphone jack, communicate by letter in addition, but be to adopt the mode directly transmitting.By after data are packed, the low and high level that original 0,1 state of data is become to earphone jack signal contact is directly communicated by letter.This mode can be to causing certain influence equipment life, and can be distorted in signal transport process, therefore can cause communication unstable, easily error code.
As shown in Figure 4, in order to realize simply and easily communication reliably, reduce communications cost, the present invention includes equipment 11 to be controlled, described equipment 11 to be controlled is connected with the audio frequency apparatus 103 in main control system 10 by audio cable 12; Main control system 10, equipment to be controlled 11 all can will be treated that communication data is modulated into sound signal, and carry out the exchange of sound signal by audio cable 12 and audio frequency apparatus 103.
Particularly, main control system 10 can comprise mobile phone, panel computer, PC and other computing equipments that comprises earphone socket, equipment 11 to be controlled can be controller of existing intelligent home device etc., when equipment 11 to be controlled is communicated by letter with main control system 10, no matter be that equipment 11 to be controlled is to the data of main control system 10 transmission, or the data that main control system 10 transfers to equipment 11 to be controlled are all modulated into sound signal, sound signal is transmitted exchange by audio frequency apparatus 103 and audio cable 12, and at equipment 11 to be controlled, main control system 10 is interior to sound signal dissection process.Audio frequency apparatus 103 can adopt existing structure, and audio frequency apparatus 103 generally can comprise sound card, driver of sound card, jack, audio microphone etc., and audio cable 12 adopts existing audio connecting cord.In addition, in the specific implementation, one end of audio cable 12 has plug that can plugged earphone socket; Other end is for accessing the connector of equipment 11 to be controlled, and the form of this connector can be headset plug, can be also self-defined socket.Conventionally signal definition is L channel, R channel, microphone and common port.Be those skilled in the art of the present technique and know, repeat no more herein.
Further, described main control system 10 comprises the host data modular converter 102 being connected with audio frequency apparatus 103 and the configuration application module 101 being connected with described host data modular converter 102;
Configuration application module 101, be connected with host data modular converter 102, data to be communicated by letter are formed to main frame and send communication data packet, and described main frame transmission communication data packet is transferred in host data modular converter 102, to be converted to main frame by host data modular converter 102, send sound signal, and can carry out dissection process to the equipment transmission communication data of host data modular converter 102 transmission;
Host data modular converter 102, the packet that configuration application module 102 is sent converts main frame to and sends sound signal, and the equipment transmission sound signal that audio frequency apparatus 103 can be received converts the required main frame received communication data of configuration application module 101 to;
Audio-frequency module 103, the main frame of host data modular converter 102 transmission is sent to sound signal and carry out playback output, and the equipment that can obtain equipment to be controlled 11 transmission by audio cable 12 sends sound signal, and equipment is sent to sound signal by host data modular converter 102, be converted to main frame received communication data.
In the embodiment of the present invention, main frame sends sound signal and refers to the data that main control system 10 sends in audio frequency mode to equipment 11 to be controlled, main frame received communication data refer to that main control system 10 receives the communication data that equipment 11 to be controlled sends, equipment sends the sound signal that sound signal refers to that equipment 11 to be controlled sends to main control system 10, and main frame received communication data refer to the data mode that the voice data of main control system 10 reception equipment 11 to be controlled can directly be processed after conversion.
Configuration application module 101 in main control system 10 is used for realizing the man-machine interface of controlling function, data to be communicated by letter have been used for generating, and data to be communicated by letter are formed to main frame transmission communication data packet, to send communication data packet by 102 pairs of main frames of host data modular converter, carry out conversion process.102 pairs of main frames of host data modular converter send communication data packet and carry out parallel-serial conversion, modulating transformation etc., main frame is sent to communication data packet and adopts FSK(Frequency-shift keying) modulation or ASK(amplitude shift keying) mode such as modulation is modulated to audiorange, to guarantee communication quality, the frequency of audio frequency can be 5KHz ~ 10KHz, certainly, in the specific implementation, also can adopt other modulation system to modulate data on audiorange, the frequency of audio frequency can be also other numerical value, the selection of described modulation system and audio frequency is the art personnel and knows, repeat no more herein.
As shown in Figure 5 and Figure 6, to adopt FSK to be modulated to example, host data modular converter 102 has different enforcement structures, and wherein, described host data modular converter 102 comprises that main frame sends data-switching portion and host receiving data converter section; Described main frame sends data-switching portion and comprises the main frame parallel serial conversion module 1021 that carries out parallel-serial conversion for main frame being sent to communication data packet, described main frame parallel serial conversion module 1021 with for Data Modulation being become the main frame sound signal modulation module of sound signal be connected;
Described host receiving data converter section comprises main frame zero-crossing detector 1023, the output terminal of main frame zero-crossing detector 1023 is connected along counter 1024 with main frame 0/1, and main frame 0/1 is connected with main frame string modular converter 1026 by main frame frequency judgement/detuner 1025 along counter 1024; Main frame frequency judgement/detuner 1025, main frame sound signal modulation module are all connected with the output terminal of main frame baud rate controller 1027.
Described main frame sound signal modulation module comprises main frame DDS signal generator 1022 or main frame square wave signal generator 1028, and described main frame square wave signal generator 1028 obtains the square-wave signal of generation after by 1031 filtering of main frame wave digital lowpass filter main frame and sends sound signal.
Particularly, for being connected between audio frequency apparatus 103 and main control system 10, equipment to be controlled 11, audio frequency apparatus 103 can comprise audio output device 1031 and voice input device 1032, by audio output device 1031, for main frame being sent to sound signal playback, export, by voice input device 1032, the equipment of equipment 11 to be controlled can be sent to sound signal reception and enter in main control system 10.
When main frame sound signal modulation module adopts main frame DDS(Direct Digital Synthesizer) during signal generator 1022, main frame DDS signal generator 1022 is connected with main frame parallel serial conversion module 1021 and main frame baud rate controller 1027, and main frame DDS signal generator 1022 is connected with audio output device 1031.Main frame parallel serial conversion module 1021 sends communication data packet by the main frame of configuration application module 101 transmission and carries out parallel-serial conversion, main control system DDS signal generator 1022 under the effect of main frame baud rate controller 1027, by DDS signal generator 1022, can directly the main frame after conversion be treated to communication data packet adopts FSK to be modulated into the sine wave signal for the treatment of playback, then send on audio output device 1031 final playback output.
When main frame sound signal modulation module adopts main frame square wave signal generator 1028, main frame square wave signal generator 1028 is connected with main frame wave digital lowpass filter 1029, main frame baud rate controller 1027, utilize main frame square wave signal generator 1028 to produce the digital square-wave of two frequencies, then through the main frame transmission communication data packet of main frame string modular converter 1021 conversions, according to the baud rate of main frame baud rate controller 1027, carry out main control system square wave signal generator 1028, select two-way different frequency square-wave signal Zhong mono-tunnel output.In the time dependent process of data stream, the fsk modulated signal of meeting formation and modification, finally by main frame wave digital lowpass filter 1029, guarantees that the signal of two Frequency points can pass through, and too high frequency is all by filtering, be conducive to like this transmit in voice-grade channel.The main frame of having modulated sends sound signal and sends on the audio output device 1031 of audio frequency apparatus 103, final playback output.
When main control system 10 receives data, host data modular converter 102 reads the equipment audio frequency transmitted signal of equipment 11 transmission to be controlled from the voice input device 1032 of audio frequency apparatus 103.Processing through main frame zero-crossing detector 1023, voice signal can be become to square wave, then utilize main frame 0/1 along 1024 pairs of variations of counter along counting, by the processing of main frame frequency judgement/detuner 1025, can obtain the frequency values of different time sections, under the control of main frame baud rate controller 1027, can recover the data stream receiving.Finally by data through 1026 conversions of main frame string modular converter, can be to the required main frame received communication data of configuration application module 101 transmission, by main frame received communication data being resolved etc., further process, can obtain required data message.
In the embodiment of the present invention, main frame parallel serial conversion module 1021, main frame string modular converter 1026 carry out two kinds of contrary conversion operations, all adopt the conventional transition form of the art, main frame DDS signal generator 1022, main frame zero-crossing detector 1023, main frame 0/1 are along the concrete course of work of counter 1024, main frame frequency judgement/detuner 1025, main frame baud rate controller 1027, main frame square wave signal generator 1028 and main frame wave digital lowpass filter 1029 and implement structure and be the art personnel and know, and repeat no more herein.
Further, described equipment to be controlled 11 comprises
Filtering processing module 113, is connected with audio cable 12 and device data modular converter 112, can send sound signal to the equipment of the main frame transmission sound signal of audio cable 12 transmission and 112 transmission of device data modular converter and carry out filtering;
Device data modular converter 112, be connected with filtering processing module 113 and microprocessor applications module 111, the main frame of filtering processing module 113 transmission can be sent to sound signal and convert the required equipment received communication data of microprocessor applications module 111 to, and the equipment sending data of microprocessor applications module 111 transmission can be converted to equipment transmission sound signal.
Described device data modular converter 112 comprises equipment input signal modular converter 1121, apparatus output signal modular converter 1122 and equipment baud rate controller 1137, and described equipment baud rate controller 1137 is connected with equipment input signal modular converter 1121 and apparatus output signal modular converter 1122.
Particularly, filtering processing module 113 is mainly that the signal for the treatment of the input and output in opertaing device 11 is done low-pass filtering.Signal for from audio cable 12 input equipment 11 to be controlled, is completed by equipment input signal low-pass filtering treatment 1131, and fundamental purpose is to remove noise, improves signal quality, guarantees the reliable of received communication.For the signal that will send, by apparatus output signal low-pass filtering treatment 1132, completed, be for square-wave signal is converted to sine wave signal, or the quantizing noise of filtering D/A, conveniently make signal pass through voice-grade channel.The processing power of considering distinct device is different, if change the section processes of filtering processing module 113 into digital filtering algorithm, in processor, moves, and is also that a kind of feasible mode and essence are identical, and this is still the application's protection domain.In the embodiment of the present invention, the baud rate parameter of the equipment baud rate controller 1137 in device data modular converter 112 and the baud rate parameter of main frame baud rate controller 1027 are in full accord.
As shown in Figure 8 and Figure 9, equipment input signal modular converter 1121 can adopt two kinds to implement structure, and particularly, described equipment input signal modular converter 1121 adopts the first input signal modular converter or the second input signal modular converter;
The first input signal modular converter comprises that the main frame for processing module 113 transmission that accept filter sends device A/D modular converter 1123 of sound signal and the equipment zero-crossing detector 1128 being connected with device A/D modular converter 1123; Described equipment zero-crossing detector 1128 is connected along counter 1129 with equipment 0/1, described equipment 0/1 is connected with device frequency judgement/detuner 1140 along counter 1129, and device frequency judgement/detuner 1140 and equipment string modular converter 1141 and equipment baud rate controller 1137 are connected;
The second input signal modular converter comprises that the main frame for processing module 113 transmission that accept filter sends the comparison in equipment device 1124 of sound signal and the grabber 1125 being connected with comparison in equipment device 1124 output terminals, described grabber 1125 is connected with pulsewidth/frequency computation part module 1126, pulsewidth/frequency computation part module 1126 is connected with detuner 1127, and described detuner 1127 and equipment baud rate controller 1137 and equipment string modular converter 1141 are connected.
When equipment 11 to be controlled receives data, and while adopting the first input signal modular converter to change, by device A/D modular converter 1123, the main frame of simulating signal is sent to sound signal and be directly changed into digital signal, then through equipment zero-crossing detector 1128, equipment 0/1, along counter 1129, device frequency judgement/demodulation 1040, equipment string modular converter 1141, process, and have equipment string the backward microprocessor applications module 111 transmission equipment received communication data of modular converter 1141 conversion.In the specific implementation, equipment zero-crossing detector 1128, equipment 0/1 are in full accord along structure and the principle of work of counter 1024, main frame frequency judgement/detuner 1025, main frame string modular converter 1026 with main frame zero-crossing detector 1023, main frame 0/1 in main control system 10 along counter 1129, device frequency judgement/demodulation 1040, equipment string modular converter 1141, specifically repeat no more, as shown in Figure 8.
As shown in Figure 9, when equipment 11 to be controlled receives data, and while adopting the second input signal modular converter to change, main frame audio frequency transmitted signal is become to square wave by comparison in equipment device 1124, then by pulsewidth grabber 1125, carrying out pulsewidth catches, then by equipment pulsewidth/frequency computation part module 1126, utilize out actual frequency of pulsewidth calculation of parameter that grabber 1125 obtains, frequency information is sent to detuner 1127 just can obtain serial data stream, through equipment string modular converter 1026, can obtain original communication data, can be to the required equipment received communication data of microprocessor applications module 111 transmission.
In the embodiment of the present invention, equipment 11 to be controlled can adopt any one enforcement structure in the first input signal modular converter or the second input signal modular converter, and the first input signal modular converter mode is more flexible, but operand is slightly high; The second input signal modular converter, can directly extract frequency information, and sequential operation amount is less, but needs specialised hardware pulsewidth grabber.Two schemes respectively has feature, can according to the interior microprocessor of equipment 11 to be controlled with peripheral hardware select flexibly, to reach minimizing peripheral circuit, the object reducing costs.
As shown in Figure 10, Figure 11 and Figure 12, described apparatus output signal modular converter 1122 adopts the first output signal modular converter, the second output signal modular converter or the 3rd output signal modular converter;
The first output signal modular converter comprises equipment parallel serial conversion module 1144, described equipment parallel serial conversion module 1144 is connected with equipment DDS signal generator 1143, and described equipment DDS signal generator 1143 is connected with equipment baud rate controller 1137 and equipment D/A modular converter 1142;
The second output signal modular converter comprises equipment parallel serial conversion module 1144 and the equipment square wave signal generator 1145 being connected with described equipment the module 1144 of going here and there; Described equipment square wave signal generator 1145 is connected with equipment baud rate controller 1137 and apparatus figure low-pass filter 1146, and described apparatus figure low-pass filter 1146 is connected with equipment D/A modular converter 1142;
The 3rd output signal modular converter comprises equipment parallel serial conversion module 1144 and the PWM module 1147 being connected with described equipment parallel serial conversion module 1144, and described PWM module 1147 is connected with equipment baud rate controller 1137.
As shown in figure 10, when equipment 11 to be controlled sends data, and while carrying out signal conversion by the first output signal modular converter, data to be communicated by letter in microprocessor applications module 111 are carried out parallel-serial conversion through equipment parallel serial conversion module 1021, data entry device DDS signal generator 1143 after parallel-serial conversion, and under the control of equipment baud rate controller 1137, produce the digital sine signal of FSK modulation, described digital sine signal is through after equipment D/A modular converter 1142, become the simulating signal that can transmit, the equipment that obtains sends sound signal, equipment sends sound signal through apparatus output signal low-pass filtering treatment 1132, just can will transmit by audio cable 12, enter main control system 10.
As shown in figure 11, when equipment 11 to be controlled sends data, and while carrying out signal conversion by the second output signal modular converter, data to be communicated by letter in microprocessor applications module 111 are carried out parallel-serial conversion, access arrangement square wave signal generator 1145 after parallel-serial conversion through equipment parallel serial conversion module 1021; Equipment square wave signal generator 1145 produces the square-wave signal of two-way different frequency, under the control of equipment baud rate controller 1137 and with the variation of equipment parallel serial conversion module 1021 input data, switches and selects two-way square-wave signal Zhong mono-tunnel to export; After apparatus figure low-pass filtering 1146, become and approach sinusoidal signal, then by after equipment D/A conversion 1142, become the simulating signal that can transmit, the equipment that obtains sends sound signal, equipment sends sound signal through apparatus output signal low-pass filtering treatment 1132, just can will transmit by audio cable 12, enters main control system 10.
As shown in figure 12, when equipment 11 to be controlled sends data, and while carrying out signal conversion by the 3rd output signal modular converter, data to be communicated by letter in microprocessor applications module 111 are carried out parallel-serial conversion through equipment parallel serial conversion module 1021, under the control of equipment baud rate controller 1137, directly control the frequency of PWM module 1147, the PWM waveform that output different frequency dutycycle is 50%, forms the square wave that FSK modulates; The PWM waveform of output is through 1132 filtering of apparatus output signal low-pass filtering treatment, become and approach sinusoidal simulating signal, the equipment that obtains sends sound signal, equipment sends sound signal through apparatus output signal low-pass filtering treatment 1132, just can will transmit by audio cable 12, enter main control system 10.
In the embodiment of the present invention, interior any one form that can select the first output signal modular converter, the second output signal modular converter or the 3rd output signal modular converter of equipment 11 to be controlled, compare, the first output signal modular converter, the second output signal modular converter are more flexible, convenient modification, and the 3rd output signal modular converter cost is low.The first output signal modular converter, the second output signal modular converter, the 3rd output signal modular converter carry out respectively the modulation of the modes such as FSK by equipment DDS signal generator 1143, equipment square wave signal generator 1145, PWM module 1147 respectively, to obtain required sound signal.The said equipment D/A modular converter 1142, equipment parallel serial conversion module 1144 and PWM module 1147 all can adopt conventional form.
Further, a kind of method of earphone socket swap data of passing through, comprises equipment 11 to be controlled, and described equipment 11 to be controlled is connected with the audio frequency apparatus 103 in main control system 10 by audio cable 12; Main control system 10, equipment to be controlled 11 all can will be treated that communication data is modulated into sound signal, and carry out the exchange of sound signal by audio cable 12 and audio frequency apparatus 103.
Described main control system 10, equipment to be controlled 11 comprise FSK modulation by the method for the treatment of communication data audio signal modulation, and the frequency of audio signal modulation is 5KHz ~ 10KHz.
Between the present invention's equipment 11 to be controlled and main control system 10, by audio cable 12, be connected, in equipment 11 to be controlled, main control system 10, modulate, the operation of demodulation, data to be communicated by letter can be exchanged with voice-frequency signalling, thereby can obtain the duty of equipment 11 to be controlled or treat opertaing device 11, control effectively, whole system only comprises a small amount of peripheral circuit, and cost is low, only by audio cable 12, connects, easy to use, simple and reliable.