CN109560967A - A kind of slave switching circuit and circuit control method - Google Patents
A kind of slave switching circuit and circuit control method Download PDFInfo
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- CN109560967A CN109560967A CN201811549522.1A CN201811549522A CN109560967A CN 109560967 A CN109560967 A CN 109560967A CN 201811549522 A CN201811549522 A CN 201811549522A CN 109560967 A CN109560967 A CN 109560967A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L41/00—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
- H04L41/06—Management of faults, events, alarms or notifications
- H04L41/0654—Management of faults, events, alarms or notifications using network fault recovery
- H04L41/0663—Performing the actions predefined by failover planning, e.g. switching to standby network elements
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- 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
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L43/00—Arrangements for monitoring or testing data switching networks
- H04L43/08—Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters
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Abstract
The invention discloses a kind of slave switching circuit and circuit control method, which, which is set to, is connected on multiple nodes using the communication bus of differential transfer, includes at least electronic switch and biasing resistor；When the first biasing resistor that slave switching circuit receives master control IC transmission controls signal, biasing resistor access communications bus is made present node become host node by control electronic switch conducting；Alternatively, when the second biasing resistor that slave switching circuit receives master control IC transmission controls signal, biasing resistor is detached from from communication bus, becomes present node from node by control electronic switch shutdown.The solution of the present invention solves the problems, such as that slave switches in differential transmission system using controllable hardware circuit.
Description
Technical field
The invention belongs to wire transmission technology fields, and in particular to a kind of slave switching circuit and circuit control method.
Background technique
Differential transfer is a kind of signal transmission technology, the communication system using differential transfer include difference signal wire in the same direction and
Two signal line of difference reverse signal line.It is different from the way of a traditional piece ground wire of a signal wire, differential transfer is at two
Signal is all transmitted on signal wire, the amplitude of the two signals is identical, opposite in phase, and signal receiving end compares the electricity of the two signals
Pressure difference judges the logic state of signal sending end.
A kind of typical communication system for using differential transfer is RS-485 communication system.RS-485 communication system is same
Allow to mount up to 256 nodes in bus, uses master-slave communication mode, the i.e. multiple slaves of host tape, each node
It can be set as host or slave according to demand, but a host, host and slave are only set in all nodes and believed by difference
Number line is attached and communicates.
But existing RS-485 communication system is fixed because host is arranged, when host breaks down, or according to using
When demand needs to switch host node, can not quickly, neatly carry out slave switching, cause system nonelastic, fault-tolerant ability
Difference.
Summary of the invention
The object of the present invention is to provide a kind of slave switching circuit and circuit control methods, to solve existing difference
Host node setting is fixed in Transmission system, can not flexibly be carried out the problem of slave switching, realize when host breaks down or
When needing slave to switch according to use demand, the beneficial effect of slave switching is carried out by controllable hardware circuit.
According to a first aspect of the embodiments of the present invention, a kind of slave switching circuit is provided, the slave switching circuit
It is set to and is connected on multiple nodes using the communication bus of differential transfer.The slave switching circuit includes at least electronic cutting
Pass and biasing resistor；When the first biasing resistor that the slave switching circuit receives master control IC transmission controls signal, control
The electronic switch conducting is made, the biasing resistor is accessed into the communication bus, present node is made to become host node；Or
Person controls the electronics when the second biasing resistor that the slave switching circuit receives master control IC transmission controls signal
The biasing resistor is detached from by switch OFF from the communication bus, becomes present node from node.
Optionally, which includes the first circuit branch and second circuit branch, the biasing resistor packet
Include pull-up biasing resistor and pull-down bias resistance；Wherein, the first circuit branch includes the first electronic switch and pull-up biasing resistor,
The signal wire connection in the same direction of the difference of first circuit branch one end and communication bus, the other end is connect with master control IC, then one end and electricity
Source connection；Second circuit branch includes the second electronic switch and pull-down bias resistance, second circuit branch one end and communication bus
The connection of difference reverse signal line, the other end connect with master control IC, further holds and is grounded.
Optionally, the first electronic switch is the first triode, and the first circuit branch further includes and first triode
First current-limiting resistance of base stage connection；Second electronic switch is the second triode, and second circuit branch further includes and described second
Second current-limiting resistance of the base stage connection of triode.
Optionally, when master control IC sends the first biasing resistor control signal, the first triode and the second triode are simultaneously
Voltage is pulled to supply voltage by the pull-up biasing resistor by conducting, difference signal wire in the same direction, and difference reverse signal line is logical
It crosses pull-down bias resistance and voltage is pulled down to ground voltage, pull up biasing resistor and the communication of pull-down bias resistance access differential is total
Line；
When master control IC sends the second biasing resistor control signal, the first triode and the second triode are simultaneously turned off, on
It draws biasing resistor and pull-down bias resistance to stop working, pulls up biasing resistor and pull-down bias resistance is detached from Differencing communication bus.
Optionally, electronic switch can be NPN type triode, the first biasing resistor control signal be high level signal, second
It is low level signal that biasing resistor, which controls signal,.
Optionally, in each node of multiple nodes of differential transmission system, the slave switching circuit and present node
Communication chip it is in parallel.
Optionally, which is set on each node for being connected to RS-485 communication bus.
Optionally, which is set to the control of each node in multiple nodes of Differencing communication bus
In device.
Optionally, master control IC is also used to carry out abnormality detection host node, and when detecting that host node is abnormal, to
Host node sends the second biasing resistor and controls signal, so that host node becomes from node；Also, according to setting rule from it is multiple from
A node is selected in node, and sends the first biasing resistor to the node of selection and controls signal, so that the node of selection becomes
New host node.
The solution of the present invention as a result, switches electricity by the way that slave is arranged in multiple nodes that Differencing communication bus connects
Road controls the on or off of slave switching circuit by master control IC, so that present node becomes host node or from node.By
This can control the conversion that signal controls main and subordinate node by biasing resistor, using controllable when current primary node is abnormal
Hardware circuit, solve the problems, such as in differencing communication system that slave switches, can be effectively prevented and lead to caused by hostdown
Believe the system failure, greatly improves the flexibility and fault-tolerance of communication system.
According to a second aspect of the embodiments of the present invention, a kind of circuit control method is provided, comprising: master control IC is to using poor
Divide the first node connected on the communication bus of transmission to send the first biasing resistor control signal, controls the master of the first node
Electronic switch conducting in slave switching circuit, the biasing resistor access communication in the slave switching circuit is total
Line makes the first node become host node；And the master control IC connected on the communication bus except the first segment
Other nodes except point send the second biasing resistor and control signal, in the slave switching circuit for controlling other nodes
Electronic switch shutdown, the biasing resistor in other nodes is detached from from the communication bus, make other nodes at
For from node.
Optionally, the electronic switch is NPN type triode, and the first biasing resistor control signal is high level letter
Number, the second biasing resistor control signal is low level signal.
Optionally, circuit control method further include: the master control IC carries out abnormality detection the host node, and is examining
When measuring the host node and being abnormal, Xiang Suoshu host node sends second biasing resistor and controls signal, so that the master
Node becomes from node；Also, the master control IC is regular from multiple one node of selection from node according to setting, and to
The node of selection sends first biasing resistor and controls signal, so that the node of selection becomes new host node.
The solution of the present invention as a result, is connected on multiple nodes using the communication bus of differential transfer by control
The on or off of slave switching circuit solves in differencing communication system to control host node and the setting from node
Host node and from node be arranged it is fixed and the problem of can not adjust, realizing can be promoted with the main and subordinate node of flexible setting system
The flexibility of communication system and the beneficial effect of fault-tolerance.
Other features and advantages of the present invention will be illustrated in the following description, also, partly becomes from specification
It obtains it is clear that understand through the implementation of the invention.
Below by drawings and examples, technical scheme of the present invention will be described in further detail.
Detailed description of the invention
Fig. 1 is a kind of circuit of slave switching circuit being arranged on RS-485 communication bus of the embodiment of the present invention one
Schematic diagram.
Specific embodiment
To make the object, technical solutions and advantages of the present invention clearer, below in conjunction with the specific embodiment of the invention and
Technical solution of the present invention is clearly and completely described in corresponding attached drawing.Obviously, described embodiment is only the present invention one
Section Example, instead of all the embodiments.Based on the embodiments of the present invention, those of ordinary skill in the art are not doing
Every other embodiment obtained under the premise of creative work out, shall fall within the protection scope of the present invention.
Embodiment one
The embodiment of the present invention one provides a kind of slave switching circuit, and the slave switching circuit, which is set to, to be connected to
On multiple nodes using the communication bus of differential transfer, the slave switching circuit includes at least electronic switch and biased electrical
Resistance；When the first biasing resistor that the slave switching circuit receives master control IC transmission controls signal, the electronics is controlled
The biasing resistor is accessed the communication bus, present node is made to become host node by switch conduction；Alternatively, working as the master
When slave switching circuit receives the second biasing resistor control signal of master control IC transmission, the electronic switch shutdown is controlled, with
The biasing resistor is detached from from the communication bus, becomes present node from node.
Wherein, the communication bus for using differential transfer can be any suitable communication bus, including but not limited to RS-
485 communication bus.
Using can connect multiple nodes on the communication bus of differential transfer, in the embodiment of the present invention, if without specified otherwise,
" multiple " mean two and two or more.It can be in the whole nodes or part of nodes in multiple nodes that the communication bus connects
The middle deployment slave switching circuit, to realize the flexible switching of slave.Preferably, RS-485 communication can be connected to
Slave switching circuit is set on each node of bus, to realize the effective of slave in RS-485 communication system and flexibly cut
It changes.
Using main control device is provided in the communication system where the communication bus of differential transfer, main control device passes through master control
IC sends a control signal to slave switching circuit input terminal, realizes multiple node switching controls to connecting on communication bus.
Specific to the embodiment of the present invention one, the slave switching circuit being set on each node in multiple nodes is received
The control of master control IC, master control IC control signal by biasing resistor and control the access of slave switching circuit or disengaging communication bus,
So that node where slave switching circuit becomes host node or from node.It should be noted that in the embodiment of the present invention,
" first " and " second " is only used for distinguishing different objects, is not offered as timing or ordinal relation.
Wherein, specific being arranged according to physical circuit of the first biasing resistor control signal and the second biasing resistor control signal
Difference and it is different, in practical applications, can be appropriately arranged with according to the actual situation by those skilled in the art.
In a kind of feasible pattern, the slave switching circuit includes the first circuit branch and second circuit branch, institute
Stating biasing resistor includes pull-up biasing resistor and pull-down bias resistance；Wherein, first circuit branch includes the first electronic cutting
Biasing resistor is closed and pulls up, first circuit branch one end is connect with the difference of communication bus signal wire in the same direction, another
End is connect with the master control IC, then one end connects to power supply；The second circuit branch includes the second electronic switch and pull-down bias
Resistance is set, second circuit branch one end is connect with the difference reverse signal line of the communication bus, the other end and the master
Control IC connection, another end ground connection.
It should be noted that first electronic switch and the second electronic switch can be one solely in the embodiment of the present invention one
Vertical switching device is also possible to the switching circuit being made of switching device and proper circuit, can control slave switching
The on or off of circuit.
Optionally, the first electronic switch and the second electronic switch can be achieved as triode.It, can by the way of triode
To simplify circuit realization, circuit cost of implementation is reduced.
For each branch of slave switching circuit, it is connected in three ends.For example, the first circuit branch respectively with
Difference signal wire in the same direction, master control IC are connected with power supply, control signal to receive the biasing resistor of master control IC, pass through the first electronic cutting
It closes and the voltage on difference signal wire in the same direction is pulled to the first electronic switch of supply voltage or shutdown；Second circuit branch difference
It is connected with difference reverse signal line, master control IC and ground, controls signal to receive the biasing resistor of master control IC, pass through the second electronic cutting
It closes and the voltage on difference reverse signal line is pulled down to the second electronic switch of ground voltage or shutdown.
That is, when the master control IC sends the first biasing resistor control signal, first triode and described second
Triode simultaneously turns on, and the difference signal wire in the same direction will be on voltage by the pull-up biasing resistor and first triode
It is pulled to supply voltage, the difference reverse signal line is pulled down voltage by the pull-down bias resistance and second triode
To ground voltage, the pull-up biasing resistor and the pull-down bias resistance access the communication bus；When the master control IC is sent out
When the second biasing resistor being sent to control signal, first triode and second triode are simultaneously turned off, the pull-up biasing
Resistance and the pull-down bias resistance stop working, and the pull-up biasing resistor and the pull-down bias resistance are detached from the communication
Bus.
Optionally, when the first triode and the second triode are NPN type triode, the first biasing resistor control
Signal is high level signal, and the second biasing resistor control signal is low level signal.But not limited to this, in practical application
In, those skilled in the art can also use the triode of other models, and set biased electrical according to the triode specifically used
The low and high level of resistance control signal.
In addition, first circuit branch can also include the first current limliting electricity connecting with the base stage of first triode
Resistance；The second circuit branch further includes the second current-limiting resistance connecting with the base stage of second triode.
For triode, since itself input resistance is too small, needing to connect current-limiting resistance as load in base stage makes
With preventing base current is excessive from burning triode.When using triode as switch in use, needing to make triode work when being connected
Make to be in cut-off region at saturation region, shutdown.So the resistance value selection of specific current-limiting resistance can be appropriately arranged with according to actual needs,
Only it need to enable to work when triode ON in saturation region.
In specific implementation, in each node for being provided with slave switching circuit, the slave switching circuit with
The communication chip of present node is in parallel.Also, the slave switching circuit is set in the controller of each node, in master
The slave switching circuit of node is connected, and when biasing resistor access communications bus, stable voltage difference is provided for differential line；And
Shutdown makes to be detached from from the biasing resistor of node from communication bus from the slave switching circuit of node, keeps one master and multiple slaves system
Overall load impedance stabilization.Particularly pull-down bias resistance resistance value choose, those skilled in the art can according to Ohm's law,
According to the loading condition of the number of nodes and each node that connect in bus, suitable resistance value is chosen.
And for master control IC, it, can be with other than managing the slave of control communication system under normal circumstances
Host node is carried out abnormality detection, and when detecting that host node is abnormal, Xiang Suoshu host node sends second biasing
Resistance controls signal, so that the host node becomes from node；Also, one is selected from node from multiple according to setting rule
Node, and send first biasing resistor to the node of selection and control signal, so that the node of selection becomes new
Host node.
Wherein, the setting rule can be any suitable rule, e.g., random rule, alternatively, pressing node ID
Carry out the rule of selection, alternatively, carry out the rule etc. of selection according to node load, the embodiment of the present invention to this with no restriction.
Hereinafter, carrying out example to the slave switching circuit that the embodiment of the present invention one provides with a physical circuit example
Property explanation.As shown in Figure 1, it is a kind of circuit diagram of slave switching circuit being arranged on RS-485 communication bus.
In Fig. 1, node 1 to n is the multiple nodes being connected on RS-485 communication bus, wherein the load of each node
Impedance determines that the maximum node quantity n, n that are connected to RS-485 communication bus are integer.U1 to Un is the RS- on each node
485 communication chips, VCC1 to VCCn are the power supply on each node, and GND1 to GNDn is the ground wire GND on each node.It is all
Power supply, the GND of node may be the same or different.
It is to control the biasing resistor in each node slave switching circuit to lead to RS-485 that biasing resistor, which controls signal 1 to n,
The control signal believing bus connection, disconnecting, derives from master control IC (not shown).R10 to Rn0, R13 to Rn3 be each section
The current-limiting resistance of point connecting triode base stage.Q10 to Qn0, Q11 to Qn1 be NPN type triode.R11 to Rn1 is each node master
The pull-up biasing resistor being connected in slave switching circuit with the difference of power supply and RS-485 communication bus signal wire A in the same direction；R12 is extremely
Rn2 is the pull-down bias being connected in each node slave switching circuit with the difference reverse signal line B of RS-485 communication bus and ground
Set resistance.
Specific connection type illustrates by taking node 1 as an example.Pull up the difference of the one end biasing resistor R11 and RS-485 communication bus
Signal wire A in the same direction is connected, and the other end is connected with the emitter of triode Q10；The collector of triode Q10 and the power supply of node 1
VCC1 is connected, and base stage is connected with the one end current-limiting resistance R10；The other end of current-limiting resistance R10 and the biasing resistor of node 1 control and believe
Number 1 is connected.One end of pull-down bias resistance R12 is connected with the difference reverse signal line B of RS-485 communication bus, the other end and three
The collector of pole pipe Q11 is connected；The emitter of triode Q11 is connected with the GND1 of node 1, and base stage is connected with current-limiting resistance R13；
The other end of current-limiting resistance R13 is connected with biasing resistor control signal 1.
The mode of action of the circuit are as follows: when biasing resistor control signal 1 is high level, triode Q10, Q11 are simultaneously turned on,
Difference signal wire A in the same direction is pulled upward to VCC1 by R11, Q10, and difference reverse signal line B pulls down to GND1 by R12, Q11.Partially
Set resistance control signal 1 be low level when, triode Q10, Q11 are simultaneously turned off, in R11, R12 stoppings drop-down effect.
When it is implemented, any one node in the node connected on RS-485 communication bus is set according to use demand
It is set to host, remaining node is set as slave.As the node of host, biasing resistor control signal is set to high electricity by master control IC
It is flat；As the node of slave, biasing resistor control signal is set to low level by master control IC.Needing replacing host node or current
When host node failure, the biasing resistor control signal of current hosts node is set to low level by master control IC, other subordinate computer nodes
In any one node, can by biasing resistor control signal be set to high level, realize node host and slave processors switching.
It can be connected in RS-485 communication bus more through a large amount of verification experimental verification using the technical solution of the present embodiment
In a node, by master control IC control slave switching circuit on or off so that present node become host node or from
Node solves the problems, such as that slave switches in RS-485 communication system, and can effectively prevent communication system caused by hostdown
System failure, greatly improves the flexibility and fault-tolerance of communication system.
Using the RS-485 Transmission system of the slave switching circuit in the embodiment of the present invention one, can be applied to such as commercial
Air-conditioning one drags more, i.e. an outer machine is arranged in pairs or groups multiple RS-485 communications in several interior machines or commercial air conditioning system Centralized Monitoring
Communication between system module, or multiple RS-485 communication module systems.
Embodiment two
Second embodiment of the present invention provides a kind of circuit control methods, comprising: communication of the master control IC to use differential transfer
The first node connected in bus sends the first biasing resistor control signal, controls the slave switching circuit of the first node
In electronic switch conducting, the biasing resistor in the slave switching circuit is accessed into the communication bus, makes described the
One node becomes host node；And its in addition to the first node that the master control IC is connected on the communication bus
Its node sends the second biasing resistor and controls signal, and the electronic switch controlled in the slave switching circuit of other nodes closes
It is disconnected, the biasing resistor in other nodes is detached from from the communication bus, becomes other nodes from node.
First node can be any one appropriate node in all nodes of communication bus connection.Due to using difference
The multiple nodes connected on the communication bus of transmission are worked according to the mode of one master and multiple slaves, when one of node quilt
It determines and is arranged to after host node, remaining node is all correspondingly determined and set as from node.
Any one appropriate node in all nodes of communication bus connection can be set in master control IC, also can be set
In an independent equipment, using centralized control, pass through principal and subordinate's machine-cut on special transmission line and each node
It changes circuit to be communicated, sends the first biasing resistor control signal or the second biasing resistor controls signal.
Optionally, the electronic switch is NPN type triode, and the first biasing resistor control signal is high level letter
Number, the second biasing resistor control signal is low level signal.
Optionally, circuit control method further include: the master control IC carries out abnormality detection the host node, and is examining
When measuring the host node and being abnormal, Xiang Suoshu host node sends second biasing resistor and controls signal, so that the master
Node becomes from node；Also, the master control IC is regular from multiple one node of selection from node according to setting, and to
The node of selection sends first biasing resistor and controls signal, so that the node of selection becomes new host node.
Wherein, the setting rule can be any suitable rule, e.g., random rule, alternatively, pressing node ID
Carry out the rule of selection, alternatively, carry out the rule etc. of selection according to node load, the embodiment of the present invention to this with no restriction.
Slave switching circuit in the present embodiment is the slave switching circuit in previous embodiment one, structure and reality
Existing principle can refer to the description in previous embodiment, and details are not described herein.
The solution of the present invention as a result, is connected on multiple nodes using the communication bus of differential transfer by control
The on or off of slave switching circuit, so that host node and the setting from node are controlled, and, it is abnormal in host node
When, realize host node and switching from node, solve in differencing communication system host node and from node be arranged it is fixed and can not
The problem of adjustment, host node failure will lead to the system failure, realizing can be with the main and subordinate node of flexible setting system, and effectively prevents
Only communication system failure caused by hostdown greatly improves the flexibility of communication system and the beneficial effect of fault-tolerance.
The above description is only an embodiment of the present invention, is not intended to restrict the invention, for those skilled in the art
For member, the invention may be variously modified and varied.All within the spirits and principles of the present invention, it is made it is any modification,
Equivalent replacement, improvement etc., should be included within scope of the presently claimed invention.
Claims (12)
1. a kind of slave switching circuit, which is characterized in that the slave switching circuit is set to be connected to be passed using difference
On multiple nodes of defeated communication bus, the slave switching circuit includes at least electronic switch and biasing resistor；
When the first biasing resistor that the slave switching circuit receives master control IC transmission controls signal, the electronics is controlled
The biasing resistor is accessed the communication bus, present node is made to become host node by switch conduction；
Alternatively,
When the second biasing resistor that the slave switching circuit receives master control IC transmission controls signal, the electronics is controlled
The biasing resistor is detached from by switch OFF from the communication bus, becomes present node from node.
2. slave switching circuit as described in claim 1, which is characterized in that the slave switching circuit includes the first electricity
Road branch and second circuit branch, the biasing resistor include pull-up biasing resistor and pull-down bias resistance；
Wherein,
First circuit branch include the first electronic switch and pull-up biasing resistor, first circuit branch one end with it is described
The signal wire connection in the same direction of the difference of communication bus, the other end is connect with the master control IC, then one end connects to power supply；
The second circuit branch include the second electronic switch and pull-down bias resistance, second circuit branch one end with it is described
The difference reverse signal line of communication bus connects, and the other end is connect with the master control IC, another end ground connection.
3. slave switching circuit as claimed in claim 2, which is characterized in that
First electronic switch is the first triode, and first circuit branch further includes the base stage with first triode
First current-limiting resistance of connection；
Second electronic switch is the second triode, and the second circuit branch further includes the base stage with second triode
Second current-limiting resistance of connection.
4. slave switching circuit as claimed in claim 3, which is characterized in that
When the master control IC sends the first biasing resistor control signal, first triode and second triode are simultaneously
Voltage is pulled to supply voltage by the pull-up biasing resistor by conducting, the difference signal wire in the same direction, and the difference is reversed
Voltage is pulled down to ground voltage, the pull-up biasing resistor and the pull-down bias by the pull-down bias resistance by signal wire
Resistance accesses the communication bus；
When the master control IC sends the second biasing resistor control signal, first triode and second triode are simultaneously
Shutdown, the pull-up biasing resistor and the pull-down bias resistance stop working, the pull-up biasing resistor and the pull-down bias
It sets resistance and is detached from the communication bus.
5. such as the described in any item slave switching circuits of Claims 1-4, which is characterized in that the electronic switch is NPN type
Triode, the first biasing resistor control signal is high level signal, and the second biasing resistor control signal is low level
Signal.
6. such as the described in any item slave switching circuits of Claims 1-4, which is characterized in that in the every of the multiple node
In a node, the slave switching circuit is in parallel with the communication chip of present node.
7. such as the described in any item slave switching circuits of Claims 1-4, which is characterized in that the slave switching circuit
It is set on each node for being connected to RS-485 communication bus.
8. such as the described in any item slave switching circuits of Claims 1-4, which is characterized in that the slave switching circuit
It is set in the controller of each node in the multiple node.
9. such as the described in any item slave switching circuits of Claims 1-4, which is characterized in that the master control IC is also used to pair
Host node carries out abnormality detection, and when detecting that host node is abnormal, and Xiang Suoshu host node sends second biased electrical
Resistance control signal, so that the host node becomes from node；Also, a section is selected from node from multiple according to setting rule
Point, and send first biasing resistor to the node of selection and control signal, so that the node of selection becomes newly
Host node.
10. a kind of circuit control method, which is characterized in that
The first node that master control IC is connected on using the communication bus of differential transfer sends the first biasing resistor control signal, control
The electronic switch conducting in the slave switching circuit of the first node is made, by the biasing in the slave switching circuit
Resistance accesses the communication bus, and the first node is made to become host node；And
Other nodes in addition to the first node that the master control IC is connected on the communication bus send the second biasing
Resistance controls signal, the electronic switch shutdown in the slave switching circuit of other nodes is controlled, by other sections
Biasing resistor in point is detached from from the communication bus, becomes other nodes from node.
11. method as claimed in claim 10, which is characterized in that the electronic switch is NPN type triode, and described first partially
Setting resistance control signal is high level signal, and the second biasing resistor control signal is low level signal.
12. method as described in claim 10 or 11, which is characterized in that the method also includes:
The master control IC carries out abnormality detection the host node, and when detecting that the host node is abnormal, Xiang Suoshu
Host node sends second biasing resistor and controls signal, so that the host node becomes from node；
Also, the master control IC is regular from multiple one node of selection from node according to setting, and to described in selection
Node sends first biasing resistor and controls signal, so that the node of selection becomes new host node.
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| CN201811549522.1A CN109560967A (en) | 2018-12-18 | 2018-12-18 | A kind of slave switching circuit and circuit control method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113282532A (en) * | 2021-06-11 | 2021-08-20 | 成都爱旗科技有限公司 | Communication device, communication method of communication device and electronic equipment |
| CN114089043A (en) * | 2021-11-22 | 2022-02-25 | 上海美控智慧建筑有限公司 | Method, device, equipment and medium for calculating bias resistor in 485 communication circuit |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113282532A (en) * | 2021-06-11 | 2021-08-20 | 成都爱旗科技有限公司 | Communication device, communication method of communication device and electronic equipment |
| CN114089043A (en) * | 2021-11-22 | 2022-02-25 | 上海美控智慧建筑有限公司 | Method, device, equipment and medium for calculating bias resistor in 485 communication circuit |
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