CN109343396A - A kind of and machine CAN build-out resistor automatic identification circuit - Google Patents
A kind of and machine CAN build-out resistor automatic identification circuit Download PDFInfo
- Publication number
- CN109343396A CN109343396A CN201811212858.9A CN201811212858A CN109343396A CN 109343396 A CN109343396 A CN 109343396A CN 201811212858 A CN201811212858 A CN 201811212858A CN 109343396 A CN109343396 A CN 109343396A
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- Prior art keywords
- machine
- build
- out resistor
- circuit
- automatic identification
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- 230000005611 electricity Effects 0.000 claims description 4
- 230000002093 peripheral effect Effects 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 4
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 230000005856 abnormality Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000008520 organization Effects 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- WYROLENTHWJFLR-ACLDMZEESA-N queuine Chemical compound C1=2C(=O)NC(N)=NC=2NC=C1CN[C@H]1C=C[C@H](O)[C@@H]1O WYROLENTHWJFLR-ACLDMZEESA-N 0.000 description 1
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
- G05B19/042—Programme control other than numerical control, i.e. in sequence controllers or logic controllers using digital processors
- G05B19/0423—Input/output
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/40—Bus networks
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/20—Pc systems
- G05B2219/25—Pc structure of the system
- G05B2219/25257—Microcontroller
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Automation & Control Theory (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Programmable Controllers (AREA)
Abstract
The present invention discloses a kind of and machine CAN build-out resistor automatic identification circuit, and level signal all the way is increased in CAN combining system, using improved control circuit, realizes simultaneously machine CAN build-out resistor automatic identification.The present invention, which cancels, uses MCU, and peripheral components are greatly reduced, simplify circuit, reduce costs, and relative to manual matching, the present invention improves reliability, the double dominant with reliability and cost control.
Description
Technical field
The present invention relates to CAN combining systems, and in particular to a kind of build-out resistor automatic identification circuit.
Background technique
CAN bus is a kind of bus communication mode of two line differential types, can connect multiple CAN transmitting-receiving sections in bus simultaneously
Point carries out bus type data transmission.CAN bus code requirement respectively must be configuration one 120 at the bus both ends of each transmitting-receiving node
Ohm build-out resistor, to eliminate reflection.
Existing scheme mainly has artificial matching and realizes that Auto-matching realizes matching electricity in the way of both by MCU on the market
The installation of resistance.
Artificial matching be after system installs, by be arranged on terminal module toggle switch perhaps wire jumper or
The method for increasing non-essential resistance, gives bus widening resistance.This manual method generally requires the ability after system installs
It carries out, inefficiency, and is easy error, lead to communication abnormality.
Realize that Auto-matching is turned on using CAN transceiver, MCU control unit, terminal resistance and resistance using MCU
Close, this mode is finished when CAN transmitting-receiving node accesses the bus cable, CAN bus power on after to the CAN transmitting-receiving node of access
It is encoded, the sequential organization by size of the coding of CAN transmitting-receiving node, so that the CAN transmitting-receiving node at bus cable both ends is compiled respectively
There is the coding of minimum and maximum, the micro-control unit MCU is accordingly to the electricity for being composed of the CAN transmitting-receiving node that minimum and maximum encodes
Resistance, which turns on, puts row closure control into, to realize that the terminal resistance of CAN transmitting-receiving node at bus cable both ends automatically accesses bus
Cable.This control mode realizes automatic control, but internal control is complicated, the MCU control unit higher cost needed, this
Outer MCU also needs peripheral circuit to set up, and occupied space and volume are larger on PCB.
Summary of the invention
It is an object of the invention to overcome prior art defect, oneself of a kind of circuit, realization and machine CAN build-out resistor are provided
Dynamic identification.
The present invention adopts the following technical scheme:
A kind of and machine CAN build-out resistor automatic identification circuit, characterized by comprising:
The level signal all the way that machine input terminal together: receiving upper one and machine equipment is sent；
Machine output end together: send all the way level signal to next simultaneously machine equipment；
One build-out resistor cuts control circuit, it includes:
First input end: being connected to and machine input terminal；
Second input terminal: being connected to and machine output end；
Control output end: a control relay circuit, the incision or disconnection of the relay control build-out resistor are connected to.
The further technical solution of the present invention is:
And machine input end signal is 0, and when machine output end signal is 1, host when equipment is multi-machine parallel connection, build-out resistor cut
Enter；
And machine input end signal be 1, and machine output end signal be 1 when, equipment be multi-machine parallel connection when intermediate slave, build-out resistor
It disconnects；
And machine input end signal be 1, and machine output end signal be 0 when, equipment be multi-machine parallel connection when end slave, build-out resistor
Incision；
And machine input end signal is 0, and when machine output end signal is 0, equipment is single machine, build-out resistor incision.
Beneficial effect
The present invention increases level signal all the way in CAN combining system, using improved control circuit, realizes simultaneously machine CAN
Build-out resistor automatic identification.The present invention, which cancels, uses MCU, and peripheral components are greatly reduced, simplify circuit, reduce costs,
Relative to manual matching, the present invention improves reliability, the double dominant with reliability and cost control.
Detailed description of the invention
Fig. 1 is the matched frame diagram of CAN automatic resistance in parallel；
Fig. 2 is one circuit diagram of embodiment；
Fig. 3 is two circuit diagram of embodiment.
Specific embodiment
In order to make those skilled in the art better understand the technical solutions in the application, below in conjunction with the application reality
The attached drawing in example is applied, the technical scheme in the embodiment of the application is clearly and completely described, it is clear that described implementation
Example is merely a part but not all of the embodiments of the present application.Based on the embodiment in the application, this field is common
The application protection all should belong in technical staff's every other embodiment obtained without creative efforts
Range
Fig. 1 is that the matched frame diagram of overall parallel connection CAN automatic resistance passes through per machine equipment together by network interface connection CAN bus
Control circuit control switch automatically selects incision or disconnects build-out resistor.
Embodiment one
As shown in Fig. 2, the present invention builds control circuit using multichannel triode, it is increase all the way in CAN line is output and input more
CAN_IN: 5V level signal receives the 5V level signal that a upper transmitting comes, connects cable；CAN_OUT: it is sent to next
5V level signal, connects cable.
Using the signal, automatic identification local state, such as CAN_IN=0, CAN_OUT=1, then when the machine is multi-machine parallel connection
Host；Such as CAN_IN=1, CAN_OUT=1, then intermediate slave when the machine is multi-machine parallel connection；Such as CAN_IN=1, CAN_OUT=0,
Most end slave when then the machine is multi-machine parallel connection；Such as CAN_IN=0, CAN_OUT=0, then the machine is single machine.
Circuit operation principle is described in detail below:
Using the circuit of the 5V Design of Signal control CAN terminal coupling resistance of above-mentioned CAN_IN and CAN_OUT, logically realize
Auto-matching resistance cuts function.
Cutting control circuit includes PNP type triode Q1, NPN type triode Q2 and Q3, CAN_IN signal connecting triode
The base stage of Q1, CAN_OUT signal connect the emitter-base bandgap grading of Q1, the grounded collector of Q1；The base stage of triode Q2 connects penetrating for triode Q1
Pole, the collector of Q2 connect the first power supply (5V power supply) anode, the emitter grounding of Q2；Triode Q3 base stage connects the current collection of triode Q2
Pole, the collector connection relay control terminal of Q3, the emitter grounding of Q3.
Be equipped with the terminal coupling resistance R1 that can cut between CAN_H and CAN_L, relay control CAN_H and CAN_L it
Between terminal coupling resistance R1 incision or disconnect.
Single machine state
CAN_IN=0, CAN_OUT=0, relay lean on the control circuit of itself, and closure cuts build-out resistor.
Specifically: CAN_IN=0, CAN_OUT=0, the base stage of triode Q1 and the signal of collector are all low level 0V, Q1
It is failure to actuate；Q2 is the conducting of NPN type high level, therefore when the base stage of triode Q2 connection CAN_OUT=0, Q2 is disconnected, Q2 collector
Q3 is connected in the base stage of 5V power supply connection Q3, and the relay switch closure on Q3 collector circuit cuts build-out resistor R1.
And machine state
Host Status: CAN_IN=0, CAN_OUT=1, relay closure, host cut build-out resistor；
Specifically: CAN_IN=0, CAN_OUT=1, triode Q1 are positive-negative-positive, and Q1 base stage is the low level of CAN_IN=0, Q1 conducting；
After Q1 conducting, then the base stage of triode Q2 is low level, and Q2 is NPN type, and Q2 is disconnected；Then the 5V power supply of Q2 collector connects Q3
Base stage Q3 is connected, Q3 conducting, relay closure, host cut build-out resistor R1.
Intermediate slave status: CAN_IN=1；CAN_OUT=1, relay disconnect, and intermediate slave disconnects build-out resistor；
Specifically: CAN_IN=1；CAN_OUT=1, Q1 are disconnected, and Q2 conducting, Q3 is disconnected, and relay disconnects, intermediate slave disconnection
With resistance.
Last bit slave status: CAN_IN=1；CAN_OUT=0, relay closure, last bit slave cut build-out resistor；
Specifically: CAN_IN=1；CAN_OUT=0, Q1 are disconnected, and Q2 is disconnected, Q3 closure, relay closure, the incision of last bit slave
With resistance.
Only intermediate slave does not cut build-out resistor, and host (First), single machine and last bit slave (last) are all
Interlaminated resistance is cut,
Regardless of simultaneously how many, machine, First and last machine will cut build-out resistor.
Detailed elaboration only is carried out to the present invention by taking triode as an example above, those skilled in the art have full knowledge that, can
Identical control function is realized to do equivalent replacement using other switching tube, is not limited in triode.
Embodiment two:
As shown in figure 3, increasing level signal all the way in CAN line, in CAN input port and output port, which distinguishes table
It is shown as CAN_IN and CAN_OUT, the control circuit of CAN build-out resistor includes input terminal A and input terminal B, receives come from respectively
The level signal of CAN input port and output port, the level signal high level can for 3V or other, the control circuit is main
Including with circuit part and inverter circuit part, include two in parallel diode D1 and D2 with circuit part, diode D1's is negative
Pole connects input terminal A, and the cathode of diode D2 connects input terminal B, and the anode of diode D1, D2 is connected to the by a resistance R
One positive pole+Ec, a N-type triode Q, the base stage of triode are connected on the node that resistance R is connected with diode D1, D2,
The collector of triode connects power supply Ucc, the emitter ground connection of triode.The collector of triode is also connect with relay for controlling
Relay processed, to realize the automatic incision of CAN build-out resistor.
Working principle is: as long as when having one in CAN_IN signal and CAN_OUT signal or being all low level, two poles
The conducting of pipe circuit, triode Q base stage are low level, and triode cut-off, then the control terminal of connecting triode collector is high level,
Control relay closure build-out resistor incision；Only when CAN_IN signal and CAN_OUT signal are high level, diode
D1, D2 are not turned on, and transistor base is high level, and triode ON, transistor collector is low level, connecting triode collection
The control terminal of electrode is low level, and relay disconnects, and build-out resistor does not access.
CAN automatic identification and incision build-out resistor of the invention can cut automatically build-out resistor when single machine use, also
It can be in multi-computer system and machine: being able to achieve Auto-matching terminal resistance when multi-machine parallel connection or series connection.
Claims (9)
1. a kind of and machine CAN build-out resistor automatic identification circuit, characterized by comprising:
The level signal all the way that machine input terminal together: receiving upper one and machine equipment is sent；
Machine output end together: send all the way level signal to next simultaneously machine equipment；
One build-out resistor cuts control circuit, it includes:
First input end: being connected to and machine input terminal；
Second input terminal: being connected to and machine output end；
Control output end: a control relay circuit, the incision or disconnection of the relay control build-out resistor are connected to.
2. as described in claim 1 and machine CAN build-out resistor automatic identification circuit, it is characterised in that:
And machine input end signal is 0, and when machine output end signal is 1, host when equipment is multi-machine parallel connection, build-out resistor cut
Enter；
And machine input end signal be 1, and machine output end signal be 1 when, equipment be multi-machine parallel connection when intermediate slave, build-out resistor
It disconnects；
And machine input end signal be 1, and machine output end signal be 0 when, equipment be multi-machine parallel connection when end slave, build-out resistor
Incision；
And machine input end signal is 0, and when machine output end signal is 0, equipment is single machine, build-out resistor incision.
3. as claimed in claim 1 or 2 and machine CAN build-out resistor automatic identification circuit, it is characterised in that the build-out resistor
Cutting control circuit includes:
First triode: base stage is connected to the first input end, and emitter is connected to second input terminal, and collector connects
Ground；
Second triode: base stage is connected to the emitter of the first triode, collector be connected to the first positive pole and it is described after
Electrical apparatus control circuit, the voltage value of first positive pole and the high level voltage value of the level signal are equal, emitter
Ground connection.
4. as claimed in claim 3 and machine CAN build-out resistor automatic identification circuit, it is characterised in that:
Second triode is connected to the control relay circuit, the base of the third transistor by a third transistor
Pole is connected to the collector of the second triode, and collector connects the control relay circuit, emitter ground connection.
5. as claimed in claim 1 or 2 and machine CAN build-out resistor automatic identification circuit, it is characterised in that the build-out resistor
Cutting control circuit includes:
With logic circuit: one input terminal connect the first input end, another input terminal connects second input terminal,
Its output end is connected to the first positive pole, the voltage value of first positive pole and the high level voltage of the level signal
It is worth equal；
Logical not component: its input terminal connection output end with logic circuit, output end connect the relay control
Circuit.
6. as claimed in claim 5 and machine CAN build-out resistor automatic identification circuit, it is characterised in that:
The diode that include two with logic circuit in parallel, the cathode of a diode connect the first input end, separately
The cathode of one diode connects second input terminal, and the anode of two diodes is connected with each other and by a resistance connection
To first positive pole；The logical not component includes a triode, and the base stage of triode is connected to two diode phases
On the node to connect, collector is connected to the control relay circuit, emitter ground connection.
7. a kind of CAN and machine equipment, it is characterised in that and machine CAN build-out resistor any described comprising claim 1,2,4 or 6
Automatic identification circuit.
8. a kind of CAN and machine equipment, it is characterised in that include as claimed in claim 3 and machine CAN build-out resistor automatic identification electricity
Road.
9. a kind of CAN and machine equipment, it is characterised in that include described in claim 5 and machine CAN build-out resistor automatic identification electricity
Road.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811212858.9A CN109343396A (en) | 2018-10-18 | 2018-10-18 | A kind of and machine CAN build-out resistor automatic identification circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811212858.9A CN109343396A (en) | 2018-10-18 | 2018-10-18 | A kind of and machine CAN build-out resistor automatic identification circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109343396A true CN109343396A (en) | 2019-02-15 |
Family
ID=65309966
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811212858.9A Pending CN109343396A (en) | 2018-10-18 | 2018-10-18 | A kind of and machine CAN build-out resistor automatic identification circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109343396A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109901540A (en) * | 2019-04-03 | 2019-06-18 | 江苏凯创电子科技有限公司 | A kind of and machine CAN build-out resistor automatic matching method, circuit and equipment |
| CN114498547A (en) * | 2022-01-11 | 2022-05-13 | 深圳市有为信息技术发展有限公司 | Configurable CAN terminal resistor matching circuit |
| CN115996156A (en) * | 2023-03-21 | 2023-04-21 | 国仪量子(合肥)技术有限公司 | Bus network system and impedance matching method thereof |
| CN109901540B (en) * | 2019-04-03 | 2024-06-25 | 江苏凯创电子科技有限公司 | Automatic matching method, circuit and equipment for parallel machine CAN matching resistor |
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| CN206135956U (en) * | 2016-11-09 | 2017-04-26 | 广州标程电气有限公司 | Automatic switch CAN node of terminating resistance |
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| CN207560031U (en) * | 2017-10-17 | 2018-06-29 | 潍柴动力股份有限公司 | The controllable controller of CAN communication circuit terminal resistance |
| CN207965562U (en) * | 2018-01-30 | 2018-10-12 | 北京智行鸿远汽车有限公司 | CAN bus terminal resistance configuration circuit |
| CN208766506U (en) * | 2018-10-18 | 2019-04-19 | 艾乐德电子（南京）有限公司 | A kind of and machine CAN build-out resistor automatic identification circuit and CAN and machine equipment |
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2018
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| US6587968B1 (en) * | 1999-07-16 | 2003-07-01 | Hewlett-Packard Company | CAN bus termination circuits and CAN bus auto-termination methods |
| CN101662405A (en) * | 2009-09-25 | 2010-03-03 | 国电南京自动化股份有限公司 | Communication circuit of CAN bus |
| US20160204818A1 (en) * | 2015-01-13 | 2016-07-14 | Hyundai Motor Company | Method for controlling controller area network transceiver circuit and device therefor |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109901540A (en) * | 2019-04-03 | 2019-06-18 | 江苏凯创电子科技有限公司 | A kind of and machine CAN build-out resistor automatic matching method, circuit and equipment |
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| CN114498547A (en) * | 2022-01-11 | 2022-05-13 | 深圳市有为信息技术发展有限公司 | Configurable CAN terminal resistor matching circuit |
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