CN202166856U - Slave receiving circuit of M-BUS - Google Patents
Slave receiving circuit of M-BUS Download PDFInfo
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- CN202166856U CN202166856U CN2011201664660U CN201120166466U CN202166856U CN 202166856 U CN202166856 U CN 202166856U CN 2011201664660 U CN2011201664660 U CN 2011201664660U CN 201120166466 U CN201120166466 U CN 201120166466U CN 202166856 U CN202166856 U CN 202166856U
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Abstract
A slave receiving circuit of an M-BUS is suitable for a slave device in an M-BUS system to receive signals sent by a master device. The slave receiving circuit of an M-BUS comprises a single-chip microcomputer, a communication interface assembly, a DC power supply assembly and other function assembly. The communication interface assembly comprises a bridge type rectification circuit and a resistor branch circuit. Signals of the slave device are input by an M-BUS system main machine, rectified by a rectifier bridge and then are divided by a resistor network. After voltage reduction, the signals are directly connected with the ADC input terminal of the single-chip microcomputer, and the input signals are measured by an ADC input module. The boundary threshold of high and low electric signals input by the M-BUS is calculated based on values obtained from measurement. After the boundary threshold is set, the ADC module or an analog comparator module is started. Through comparison between the input signals and the boundary threshold, communication and interception are carried out for the signals input by the bus. Therefore, a function of communication data reception is realized. The slave receiving circuit of an M-BUS has the characteristics of strong anti-interference capability and low cost.
Description
Technical field:
The utility model relates to a kind of slave receiving circuit of M-BUS bus; Be adapted to the signal in the M-BUS bus system, especially pass through the M-BUS bus and form number biography direct-reading water meter, gas meter, ammeter and other warnings, watch-dog in the system of network with management host equipment from the transmission of machine equipment reception main process equipment.
Background technology:
In recent years, meet the Meter-BUS bus of EN1343-3 standard, be called for short the M-BUS bus network; Because its communication only needs two core leads, nonpolarity input, and can Y-connection; Make easy construction, greatly reduce construction labour intensity, improve the stability of system; Make the communication network of M-BUS bus in digital remote kilowatt meter reading-out system, alarm monitoring system, obtain using widely, accomplish by dedicated IC chip coding, decoding from machine equipment (Slave) usually, but this dedicated IC chip price is too high; Make the cost of product very high; Suppressed the popularization of M-BUS bus system, moreover this integrated circuit is packaged together rectifier stack, the power supply module of M-BUS bus input simultaneously, belongs to from bus and inhale the constant current source structure that stream is no more than 10mA; And output voltage has only 3.3V, has further suppressed the popularization of this bus system.
For reducing cost of products; Many people attempt using resolution element to form the function of M-BUS bus protocol code requirement, but usually except that needs use one group of rectifier bridge, also need use a plurality of triodes, a plurality of diode and some resistance, capacitor element; Individual other also need use at least one large bulk capacitance; The use of large bulk capacitance, the capacitive that has increased the M-BUS bus system is disturbed, and causes the instability of communication easily; The use of the discrete device that quantity is many causes failure factor to increase, and also will strengthen the size of wiring board; Be unfavorable for use like the limited product of circuit board installation volume such as water meter, like this, though reduced cost of products; Simultaneously also reduced performance of products, also difficulty has broad application prospect.
Summary of the invention:
The purpose of design of the utility model is: the slave receiving circuit that a kind of M-BUS bus is provided; Be applicable to the signal in the M-BUS bus system from the transmission of machine equipment reception main process equipment; It is cheap that the M-BUS bus communication that adopts this method design is had from machine equipment, stable performance, uses the few characteristics of electronic devices and components quantity simultaneously.
The slave receiving circuit of the M-BUS bus that the utility model provided comprises: single-chip microcomputer, communication interface assembly, direct current supply assembly, and wherein single-chip microcomputer is built-in with the analog to digital converter module; Be called for short the ADC module, or be built-in with ADC module and analog comparator module simultaneously; The communication interface assembly comprises bridge rectifier circuit, resistor voltage divider circuit, and the input of M-BUS bus system main process equipment connects rectifier bridge from the signal of machine equipment; Input signal is after the rectifier bridge rectification; Output to resistor voltage divider network, by the resistor network dividing potential drop, the signal after the step-down directly connects Chip Microcomputer A C input port and analog comparator module port.
The utility model is for realizing above-mentioned purpose: on the basis with a kind of method, provide two covers different implementations, accomplished in the M-BUS bus system and receive the signal that main process equipment sends from machine equipment:
Base case is: the input signal after the ADC module is to dividing potential drop is changed, is measured, and by measuring the boundary threshold value that resulting numerical value determines high and low electric signal, according to the internal resource of the single-chip microcomputer that adopts, determines the concrete measure of implementing again.
First sets of plan is: from machine equipment by the input signal of M-BUS bus system main process equipment after the rectifier bridge rectification; Through electric resistance partial pressure; Signal after the step-down directly connects Chip Microcomputer A C input port, and the signal method that receives the main process equipment transmission from machine equipment is: in advance the high level and the low level signal of M-BUS bus host device transmission are carried out analog to digital conversion through the ADC module from machine equipment, the ADC conversion value that obtains M-BUS bus host device transmission high level is: HVref; The low level ADC conversion value of M-BUS bus host device transmission is: LVref; Boundary reference threshold when getting a suitable value conduct from machine equipment reception " height ", " low " level between HVref and the LVref is defined as: Vref, slave device start ADC module; Intercept the signal that main process equipment sends; When the ADC of input signal conversion value was higher than Vref, the signal level that receives was high level " 1 ", when the ADC of input signal conversion value is lower than Vref; The signal level that receives is low level " 0 ", and the concrete course of work is:
(1), power on stable after, at first to the calibration of M-BUS bus host device transmission high level, keep when sending high level state at the M-BUS main process equipment; Start the ADC conversion; And the ADC conversion value of record M-BUS bus host device transmission high level, be defined as: HVref
(2), main process equipment sends a group or a low level signal pulse, from machine equipment low level signal done the ADC conversion, the conversion value that obtains is defined as: LVref,
(3), the boundary reference value when getting a suitable value conduct between HVref and the LVref from machine equipment reception " height ", " low " level; Be defined as: Vref; When the ADC conversion value was higher than Vref, the signal level that receives was high level " 1 ", when the ADC conversion value is lower than Vref; The signal level that receives is low level " 0 "
(4), start the ADC conversion, intercept the signal that main process equipment sends, through the ADC conversion, accomplish identification to the bus transfer signal, realize communication function.
For most M-BUS bus communication systems, the voltage difference when clear and definite main process equipment transmission " height ", " low " level, the voltage difference during according to the main process equipment transmission " height " of making an appointment, " low " level; Calculate the pairing ADC conversion value of this voltage difference; Be defined as: SVref, the ADC conversion value that the high level of M-BUS bus host device transmission is corresponding: HVref measures through the ADC module converts; Boundary reference threshold when getting a suitable value conduct between HVref and the HVref-SVref from machine equipment reception " height ", " low " level; Be defined as: Vref, slave device start ADC module is intercepted the signal that main process equipment sends; When the ADC of input signal conversion value is higher than Vref; The signal level that receives is high level " 1 ", and when the ADC of input signal conversion value was lower than Vref, the signal level that receives was low level " 0 ".
Second sets of plan is: the single-chip microcomputer of use is built-in with analog to digital converter module and analog comparator module simultaneously; Main process equipment input after the rectifier bridge rectification, is adopted electric resistance partial pressure from the signal of machine equipment, and the signal after the dividing potential drop connects analog to digital converter module and the analog comparator module from machine equipment; Earlier input signal is switched to an input port of Chip Microcomputer A C module; In advance the high level and the low level signal of M-BUS bus host device transmission are carried out analog to digital conversion through the ADC module from machine equipment, the ADC conversion value that obtains M-BUS bus host device transmission high level is: HVref, and the low level ADC conversion value of M-BUS bus host device transmission is: LVref; Boundary reference threshold when getting a suitable value conduct between HVref and the LVref from machine equipment reception " height ", " low " level; Be defined as: Vref switches to input signal an input port of single-chip simulation comparer, again by the reference voltage level of the value adjustment analog comparator of acquired Vref; Be defined as CVref; When the value of input signal was higher than CVref, the signal level that receives was defined as high level " 1 ", when the value of input signal is lower than CVref; The signal level that receives is defined as low level " 0 ", and its course of work is:
(1), power on stable after; At first to the calibration of M-BUS bus host device transmission high level, when the M-BUS main process equipment was kept the transmission high level state, input signal switched to Chip Microcomputer A C input port earlier; Start the ADC conversion; And the ADC conversion value of record M-BUS bus host device transmission high level, be defined as: HVref
(2), main process equipment sends a group or a low level signal pulse, from machine equipment low level signal done the ADC conversion, the conversion value that obtains is defined as: LVref,
(3), the boundary reference value when getting a suitable value conduct between HVref and the LVref from machine equipment reception " height ", " low " level; Be defined as: Vref switches to an input port of single-chip simulation comparer with input signal, the reference voltage level of the value adjustment analog comparator through Vref; Be defined as CVref; When the value of input signal was higher than CVref, the signal level that receives was defined as high level " 1 ", when the value of input signal is lower than CVref; The signal level that receives is defined as low level " 0 "
(4), start analog comparator, intercept the signal that main process equipment sends, accomplish identification to the bus transfer signal, realize communication function.
In the actual use of second sets of plan, the M-BUS system of the voltage difference when clearly stipulating main process equipment transmission " height ", " low " level wherein, the value of Vref through M-BUS bus host equipment is sent the high level actual measurement; The calculating low level value is obtained, and process is main process equipment input from the signal of machine equipment after the rectifier bridge rectification, adopts electric resistance partial pressure; Signal after the dividing potential drop connects analog to digital converter module and the analog comparator module from machine equipment, earlier input signal is switched to an input port of Chip Microcomputer A C module, the ADC conversion value that the high level of M-BUS bus host device transmission is corresponding: HVref; Measure through the ADC module converts; Voltage difference during according to the main process equipment transmission " height " of making an appointment, " low " level calculates the pairing ADC conversion value of this voltage difference, is defined as: SVref; Boundary reference threshold when getting a suitable value conduct between HVref and the HVref-SVref from machine equipment reception " height ", " low " level; Be defined as: Vref switches to input signal an input port of single-chip simulation comparer, again by the reference voltage level of the value adjustment analog comparator of acquired Vref; Be defined as CVref; When the value of input signal was higher than CVref, the signal level that receives was defined as high level " 1 ", when the value of input signal is lower than CVref; The signal level that receives is defined as low level " 0 ", realizes communication.
The utility model advantage is:
1, only use one group of rectifier bridge and divider resistance, adopt the built-in ADC of single-chip microcomputer, or ADC adds the analog comparator module combinations and accomplish M-BUS from the machine equipment receiving function, device is few, and cost is low.
2, peripheral components is few, and it is few especially bus to be had capacitive, a perceptual device of interference, few to the interference of M-BUS bus, makes system stable more, reliable.
3, the slave device power supply (DPS) directly extracts from bus, and output voltage and electric current can be adjusted according to different requirement.
Description of drawings:
Fig. 1: the utility model embodiment M-BUS bus host equipment sends signal schematic representation.
Fig. 2: one of the utility model embodiment M-BUS bus slave computer equipment electricity principle schematic.
Fig. 3: two of the utility model embodiment M-BUS bus slave computer equipment electricity principle schematic.
Embodiment:
Below in conjunction with accompanying drawing, the utility model is done further explanation:
As shown in Figure 1: the M-BUS bus host equipment related to present embodiment sends the simple and easy description of signal; In the drawings; Given main process equipment transmission signals be more common magnitude of voltage; The voltage of main process equipment mark (keep high level or send the logical one signal): Vmark=20.8V-42V, the voltage of main process equipment spacing (sending the logical zero signal): Vspace=Vmark-10V.
In illustration: it is undamped that the transmission signal of supposition M-BUS bus host equipment is transferred to M-BUS bus slave computer equipment, supposes Vmark=30V, Vspace=20V.
In conjunction with Fig. 2; Concrete analysis originally is first embodiment of invention; M-BUS bus slave computer circuitry comprises: SCM system (U1), bus input and rectifier bridge assembly (DB), resistor voltage divider network (R1, R2), power supply module, communication sending assembly; Other functional modules, single-chip microcomputer are built-in with the ADC module.
M-BUS bus host equipment sends signal after rectifier bridge (DB) rectification, and (R1, R2) carries out voltage division processing by resistor voltage divider network, and voltage after partial Vin directly connects (ADC) input pin of single-chip microcomputer.
Its communication flow is:
(1), M-BUS bus host equipment sends earlier the Vmark signal, i.e. logical one signal, and the time of keeping certain-length powers on to guarantee M-BUS bus slave computer equipment reliable; Suppose Vmark=30V, behind the slave device start, earlier the Vmark high level is calibrated; Promptly pass through resistor voltage divider network (R1, R2) to the input signal dividing potential drop after the rectification, promptly partial pressure value is Vin, supposes from machine equipment at the partial pressure value that receives the Vmark signal: Vin=3V; ADC reference voltage Vref=the 3.6V of single-chip microcomputer when the M-BUS main process equipment is kept the transmission high level state, starts the ADC conversion; And the ADC conversion value of record M-BUS bus host device transmission high level, be defined as: HVref, under above assumed conditions; The precision of supposing ADC simultaneously is 8 bit lengths, then HVref=0xD5
(2), the voltage difference during according to the main process equipment of making an appointment transmission " height ", " low " level, suppose Vmark-Vspace=10V in this example, Vspace=20V; Promptly calculate the pairing ADC conversion value of this voltage difference; Be defined as: SVref, computational data is: SVref=0x47
(3), getting a suitable value between HVref and the HVref-SVref as the boundary reference value when machine equipment receives " height ", " low " level, be defined as: Vref, when the ADC conversion value is higher than Vref; The signal level that receives is high level " 1 ", and when the ADC conversion value was lower than Vref, the signal level that receives was low level " 0 "; According to this example: HVref-SVref=0x8E, then Vref is greater than 0x8E, less than 0xD5; For communication robust; The value of general Vref is near intermediate value, definable Vref=0xB1
(4), start the ADC conversion, intercept the signal that main process equipment sends, through the Vin signal being carried out the ADC conversion; Completion is to the identification of bus transfer signal; Realize communication function, when ADC conversion value during greater than 0xB1, the signal level that receives is high level " 1 " in this example; When ADC conversion value during less than 0xB1, the signal level that receives is low level " 0 ".
In the communication implementation; The threshold value of Vref can also be obtained through Vmark, the actual measurement of Vspace level signal that M-BUS bus host equipment is sent, and after the measurement of accomplishing " HVref ", the main process equipment of can making an appointment sends the pulse of a group or a Vspace low level signal; From machine equipment the Vspace low level signal of input is made the ADC converted measurement; The conversion value that obtains is defined as: LVref, the boundary reference value when getting a suitable value conduct from machine equipment reception " height ", " low " level between HVref and the LVref is defined as: Vref; When the ADC conversion value is higher than Vref; The signal level that receives is high level " 1 ", and when the ADC conversion value was lower than Vref, the signal level that receives was low level " 0 ".
In conjunction with Fig. 1 and Fig. 3; Concrete analysis originally is second embodiment of invention; M-BUS bus slave computer circuitry comprises: single-chip microcomputer (U1), bus input and rectifier bridge assembly (DB), resistor voltage divider network (R1, R2), power supply module, communication sending assembly; Other functional modules, single-chip microcomputer are built-in with ADC module and analog comparator module, and the single-chip microcomputer that present embodiment adopts is: the built-in ADC module and the input Vin-of analog comparator hold a multiplexing pin; Can switch through built-in switch, the input Vin+ of analog comparator is provided by the built-in reference source of single-chip microcomputer.
M-BUS bus host equipment sends signal after rectifier bridge (DB) rectification, and (R1, R2) carries out voltage division processing by resistor voltage divider network, and voltage after partial Vin directly connects (ADC) input pin of single-chip microcomputer and the Vin-end complexing pin of analog comparator.
Its communication flow is:
(1), power on stable after; At first to the calibration of M-BUS bus host device transmission high level, when the M-BUS main process equipment was kept the transmission high level state, input signal connected Chip Microcomputer A C input port earlier; Start the ADC conversion; And the ADC conversion value of record M-BUS bus host device transmission high level, be defined as: HVref
(2), the voltage difference during according to the main process equipment of making an appointment transmission " height ", " low " level, calculate the pairing ADC conversion value of this voltage difference, be defined as: SVref,
(3), the boundary reference value when getting a suitable value conduct between HVref and the HVref-SVref from machine equipment reception " height ", " low " level; Be defined as: Vref switches to an input port of single-chip simulation comparer with input signal, by the reference voltage level of another input port of the number adjustment analog comparator of the Vref that has obtained; Be defined as CVref; When the value of input signal was higher than CVref, the signal level that receives was defined as high level " 1 ", when the value of input signal is lower than CVref; The signal level that receives is defined as low level " 0 "
(4), start analog comparator, intercept the signal that main process equipment sends, accomplish identification to the bus transfer signal, realize communication function.
The M-BUS system of the voltage difference during (5), for off-gauge or not clear and definite main process equipment transmission " height ", " low " level; The value of Vref is obtained through the low level actual measurement that M-BUS bus host equipment is sent, and after the measurement of accomplishing HVref, can make an appointment requires main process equipment to send a group or a low level signal pulse; From machine equipment low level signal is done the ADC conversion; The conversion value that obtains is defined as: LVref, getting a suitable value as the reference value of relatively demarcating of the simulating signal when machine equipment receives " height ", " low " level, CVref between HVref and the LVref; After accomplishing the ADC conversion; Switch to the analog comparator function, when input signal values was higher than CVref, the signal level that receives was defined as high level " 1 "; When input signal values was lower than CVref, the signal level that receives was defined as low level " 0 ".
Except that the foregoing description; The utility model can also have other embodiments; As single-chip microcomputer select for use difference, ADC sampling order different or the like, adopt in every case to be equal to the technical scheme that replacement or equivalent transformation form, all drop in the protection domain of the utility model claim.
Claims (2)
1. the slave receiving circuit of a M-BUS bus is adapted to the signal from the transmission of machine equipment reception main process equipment in the M-BUS bus system, comprising: single-chip microcomputer, communication interface assembly, direct current supply assembly; It is characterized by: single-chip microcomputer is built-in with the analog to digital converter module, is called for short the ADC module, and the communication interface assembly comprises bridge rectifier circuit; Resistor voltage divider circuit; The input of M-BUS bus system main process equipment connects rectifier bridge from the signal of machine equipment, and input signal outputs to resistor voltage divider network after the rectifier bridge rectification; By the resistor network dividing potential drop, the signal after the step-down directly connects Chip Microcomputer A C input port.
2. the slave receiving circuit of M-BUS bus according to claim 1; It is characterized in that: the single-chip microcomputer of use is built-in with analog to digital converter module and analog comparator module simultaneously; Main frame input from the signal of machine equipment after the rectifier bridge rectification; Output to resistor voltage divider network, by the resistor network dividing potential drop, the signal after the step-down connects analog to digital converter module input mouth and the analog comparator module input mouth from machine equipment.
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| CN2011201664660U CN202166856U (en) | 2011-05-20 | 2011-05-20 | Slave receiving circuit of M-BUS |
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| CN2011201664660U CN202166856U (en) | 2011-05-20 | 2011-05-20 | Slave receiving circuit of M-BUS |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103809466A (en) * | 2012-11-05 | 2014-05-21 | 北汽福田汽车股份有限公司 | Controller signal processing apparatus compatible with dual-voltage |
| CN104991487A (en) * | 2015-05-20 | 2015-10-21 | 江苏骏普智能仪表有限公司 | Medium-short distance communication method |
| CN110247543A (en) * | 2019-06-21 | 2019-09-17 | 秦皇岛尼特智能科技有限公司 | A kind of circuit for reinforcing conduction interference immunity to interference in fire-fighting bus |
| CN110311845A (en) * | 2019-07-27 | 2019-10-08 | 深圳市骏普科技开发有限公司 | A kind of bus-powered method of battery-operated type M-BUS |
| CN113296436A (en) * | 2021-05-07 | 2021-08-24 | 宁波水表(集团)股份有限公司 | Slave station equipment based on MBUS bus analog circuit |
| CN113325776A (en) * | 2021-06-04 | 2021-08-31 | 宁波公牛生活电器有限公司 | Switch device and switch control system |
-
2011
- 2011-05-20 CN CN2011201664660U patent/CN202166856U/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103809466A (en) * | 2012-11-05 | 2014-05-21 | 北汽福田汽车股份有限公司 | Controller signal processing apparatus compatible with dual-voltage |
| CN104991487A (en) * | 2015-05-20 | 2015-10-21 | 江苏骏普智能仪表有限公司 | Medium-short distance communication method |
| CN110247543A (en) * | 2019-06-21 | 2019-09-17 | 秦皇岛尼特智能科技有限公司 | A kind of circuit for reinforcing conduction interference immunity to interference in fire-fighting bus |
| CN110311845A (en) * | 2019-07-27 | 2019-10-08 | 深圳市骏普科技开发有限公司 | A kind of bus-powered method of battery-operated type M-BUS |
| CN110311845B (en) * | 2019-07-27 | 2021-10-08 | 深圳市骏普科技开发有限公司 | Battery-powered M-BUS (Meter-BUS) BUS power supply method |
| CN113296436A (en) * | 2021-05-07 | 2021-08-24 | 宁波水表(集团)股份有限公司 | Slave station equipment based on MBUS bus analog circuit |
| CN113296436B (en) * | 2021-05-07 | 2022-07-15 | 宁波水表(集团)股份有限公司 | Slave station equipment based on MBUS bus analog circuit |
| CN113325776A (en) * | 2021-06-04 | 2021-08-31 | 宁波公牛生活电器有限公司 | Switch device and switch control system |
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| C14 | Grant of patent or utility model | ||
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| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20120314 Termination date: 20190520 |