CN115277282A - CAN node, working method thereof and CAN bus - Google Patents
CAN node, working method thereof and CAN bus Download PDFInfo
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- CN115277282A CN115277282A CN202110480336.2A CN202110480336A CN115277282A CN 115277282 A CN115277282 A CN 115277282A CN 202110480336 A CN202110480336 A CN 202110480336A CN 115277282 A CN115277282 A CN 115277282A
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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
- H04L12/40006—Architecture of a communication node
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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
- H04L2012/40208—Bus networks characterized by the use of a particular bus standard
- H04L2012/40215—Controller Area Network CAN
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Abstract
The invention discloses a CAN node, which comprises a controller, a CAN transceiver, a first CAN bus socket, a second CAN bus socket, a first CAN bus plug, a second CAN bus plug, a first resistor, a second resistor, a third resistor and a controllable switch, wherein the controller is connected with the CAN transceiver, the first CAN bus socket and the second CAN bus socket both comprise a plurality of pins, the 1 st pin of the first CAN bus socket and the 1 st pin of the second CAN bus socket are both connected to the controller and are respectively connected to a positive power VCC through the first resistor and the second resistor, the 2 nd pin is both grounded, the 3 rd pins of the first CAN bus socket and the second CAN bus socket are both electrically connected with the CAN transceiver and are used for transmitting CANH signals, and the 4 th pins of the first CAN bus socket and the second CAN bus socket are both electrically connected with the CAN transceiver and are used for transmitting CANL signals. The invention CAN solve the technical problem that the prior method for adjusting the terminal matching resistance needs to manually identify whether the CAN node is an intermediate CAN node or a terminal CAN node and then is connected with the terminal matching resistance.
Description
Technical Field
The invention belongs to the technical field of CAN (controller area network) buses, and particularly relates to a CAN node, a working method thereof and a CAN bus.
Background
The CAN bus is based on the parallelly connected network deployment communication network of many CAN nodes of differential cable, only needs CANH and CANL two core cable to connect between each CAN node, connects simply, and the extension is convenient, by wide use in the industry. The CAN bus realizes communication depending on the difference level on CANH and CANL cables, in order to eliminate the reflection of signals at the terminals of the CAN cables, a terminal matching resistor is required to be connected to each terminal CAN node at two ends of the CAN bus, and a middle CAN node in the middle of the CAN bus is not connected to the matching resistor. The CAN nodes that are accessed into the CAN bus are usually dynamically changed, and when a new CAN node is accessed into the existing CAN bus network or a CAN terminal CAN node is removed, the terminal CAN node of the CAN bus network will be changed, and at this moment, the terminal matching resistance of the new CAN terminal CAN node needs to be readjusted.
In order to achieve the purpose of adjusting the terminal matching resistance, two methods exist in the prior art, the first method is to identify a terminal CAN node in a manual mode, and then manually connect the terminal matching resistance to the terminal CAN node or control the connection of the terminal matching resistance by other communication means; the second is to input power voltage to drive the relay through the middle CAN node of the CAN to connect the terminal matching resistance.
However, both of the above methods have some non-negligible drawbacks: firstly, manually identifying whether a CAN node is an intermediate CAN node or a terminal CAN node, and manually connecting or disconnecting terminal matching resistors of each CAN node according to an identification result; secondly, the CAN terminal CAN not automatically adapt to the access of a new CAN node or the disconnection of the existing CAN node, and at the moment, the CAN terminal CAN change, and all CAN nodes need to be manually identified again to judge whether the CAN nodes are terminal CAN nodes or not and manually connect the terminal matching resistors; and thirdly, a power supply is output through a CAN node in the middle of the CAN to drive a relay connecting terminal of the next CAN node to match a resistor, a power line and a ground line are required to be added in a CAN bus cable, mutual interference CAN be formed among the power line, the ground line and a CAN signal line, and a corresponding interference elimination device is required to be added in the power supply and the CAN signal line of each CAN node, so that the transmission rate of CAN bus signals CAN be reduced, and the transmission error rate is increased.
Disclosure of Invention
The invention provides a CAN node, a working method thereof and a CAN bus, aiming at solving the technical problems that the existing method for adjusting the terminal matching resistance needs to manually identify whether the CAN node is an intermediate CAN node or a terminal CAN node, manually identify whether all CAN nodes are terminal CAN nodes and manually connect the terminal matching resistance, and reduce the transmission rate of CAN bus signals and increase the transmission error rate due to the need of adding corresponding interference elimination devices in power supplies and CAN signal lines of all CAN nodes.
In order to achieve the above object, according to one aspect of the present invention, there is provided a CAN node, including a controller, a CAN transceiver, a first CAN bus socket, a second CAN bus socket, a first CAN bus plug, a second CAN bus plug, a first resistor, a second resistor, a third resistor, and a controllable switch, the controller being connected to the CAN transceiver;
the first CAN bus socket and the second CAN bus socket both comprise a plurality of pins, the 1 st pin of the first CAN bus socket and the 1 st pin of the second CAN bus socket are both connected to the controller and are respectively connected to a positive power supply VCC through a first resistor and a second resistor, and the 2 nd pin is both grounded;
the 3 rd pins of the first CAN bus socket and the second CAN bus socket are electrically connected with the CAN transceiver and are used for transmitting CANH signals;
the 4 th pins of the first CAN bus socket and the second CAN bus socket are electrically connected with the CAN transceiver and are used for transmitting CANL signals;
the 4 th pin of the first CAN bus socket is also connected to the 3 rd pin of the first CAN bus socket through a third resistor and a controllable switch, and the 4 th pin of the second CAN bus socket is also connected to the 3 rd pin of the second CAN bus socket 3 through a third resistor and a controllable switch;
when the CAN node works, when a first CAN bus plug is connected into a first CAN bus socket or a second CAN bus plug is connected into a second CAN bus socket, the CAN node is used as a terminal CAN node; when the first CAN bus plug is connected to the first CAN bus socket and the second CAN bus plug is connected to the second CAN bus socket, the CAN node is used as an intermediate CAN node.
Preferably, the first CAN bus plug and the second CAN bus plug both comprise a plurality of pins, the 1 st pin of the first CAN bus plug is directly connected with the 2 nd pin of the first CAN bus plug, and the 1 st pin of the second CAN bus plug is directly connected with the 2 nd pin of the second CAN bus plug;
a 3 rd pin of a first CAN bus plug in one CAN node is connected to a 3 rd pin of a first CAN bus socket in another CAN node and is used for transmitting a CANH signal;
the 4 th pin of the first CAN bus plug in one CAN node is connected to the 4 th pin of the first CAN bus socket in the other CAN node and is used for transmitting a CANL signal;
the 3 rd pin of a second CAN bus plug in one CAN node is connected to the 3 rd pin of a second CAN bus socket in another CAN node and is used for transmitting a CANH signal;
Preferably, when the first CAN bus plug is connected to the first CAN bus socket, the 1 st pin of the first CAN bus socket is connected with the 2 nd pin, and the 1 st pin of the first CAN bus socket outputs a low level;
when the first CAN bus socket is not connected with the first CAN bus plug, the 1 st pin and the 2 nd pin of the first CAN bus socket are disconnected, and the 1 st pin of the first CAN bus socket outputs a high level;
when the second CAN bus plug is connected to the second CAN bus socket, the 1 st pin of the second CAN bus socket outputs low level;
and when the second CAN bus plug is not connected to the second CAN bus socket, the 1 st pin of the second CAN bus socket outputs high level.
Preferably, the first resistor and the second resistor have the same resistance value, and are both greater than 10k ohms;
the resistance of the third resistor is 120 ohms;
the controllable switches are MOS switches.
Preferably, the first CAN-bus socket and the second CAN-bus socket are identical, and both CAN-bus sockets are aerial sockets.
The first CAN bus plug and the second CAN bus plug are identical and are both aviation plugs.
According to another aspect of the present invention, there is provided a method for operating a CAN node, including the steps of:
(1) The CAN controller respectively acquires a first connection signal output from a 1 st pin of a first CAN bus socket and a second connection signal output from a 1 st pin of a second CAN bus socket;
(2) The CAN controller judges whether the first connection signal and the second connection signal acquired in the step (1) are both high level, if so, the step (3) is carried out, otherwise, the step (4) is carried out;
(3) The CAN controller sets a CAN node where the CAN controller is located to be in a disconnection state, and then the process is ended;
(4) The CAN controller judges whether the first connection signal and the second connection signal acquired in the step (1) are both low level, if so, the step (5) is carried out, otherwise, the step (6) is carried out;
(5) The CAN controller sets a CAN node where the CAN controller is located as an intermediate CAN node, and sets the change-over switch to be in a disconnected state so as to disconnect the third resistor, and the process is finished;
(6) The CAN controller sets the CAN node where the CAN controller is located as a terminal CAN node, and sets the change-over switch to be in a closed state so as to connect the third resistor, and the process is finished.
According to another aspect of the present invention, there is provided a CAN bus including N of the above CAN nodes, a first CAN node and an nth CAN node being terminal CAN nodes of the CAN bus, and second to nth CAN nodes-1 being intermediate CAN nodes of the CAN bus;
one end of the 1 st CAN cable is connected to a second CAN bus socket of the first CAN node through a second CAN bus plug of the first CAN node, and the other end of the 1 st CAN cable is connected to a first CAN bus socket of the second CAN node through a first CAN bus plug of the second CAN node, so that the first CAN node and the second CAN node are connected with each other;
one end of the 2 nd CAN cable is connected to a second CAN bus socket of the second CAN node through a second CAN bus plug of the second CAN node, and the other end of the 2 nd CAN cable is connected to a first CAN bus socket of the third CAN node through a first CAN bus plug of the third CAN node, so that the first CAN node is connected with the third CAN node, … …, and so on;
one end of the (N-1) th CAN cable is connected to a second CAN bus socket of the (N-1) th CAN node through a second CAN bus plug of the (N-1) th CAN node, and the other end of the (N-1) th CAN cable is connected to a first CAN bus socket of the (N) th CAN node through a first CAN bus plug of the (N) th CAN node, so that the first CAN node and the Nth CAN node are connected with each other;
a first CAN-bus socket of a first CAN-node as a terminal CAN-node is left empty, and a second CAN-bus socket of an nth CAN-node as a terminal CAN-node is left empty, where N is a positive integer.
In general, compared with the prior art, the above technical solution contemplated by the present invention can achieve the following beneficial effects:
1) All CAN nodes in the invention CAN automatically identify whether the CAN nodes are intermediate CAN nodes or terminal CAN nodes through the change of an access cable, and whether the CAN nodes are in an off-line state, and automatically access or disconnect a terminal matching resistor;
2) All CAN nodes in the invention always monitor the change of the CAN node position, when a new CAN node is accessed or a terminal CAN node is disconnected, the change of the CAN node position CAN be immediately identified, and the terminal matching resistor is automatically accessed or disconnected, thus being capable of completely and automatically adapting to any change of the CAN node of a CAN bus;
3) The CAN bus CAN realize the functions of completely and automatically identifying the position of the CAN node and automatically switching the terminal matching resistance by only using a 2-core cable, forming a detection signal of a connector by adding a first resistor and a second resistor and using the existing controller of the CAN node;
4) The CAN node has low cost and simple structure.
Drawings
FIG. 1 is a schematic diagram of a CAN bus network structure composed of a plurality of CAN nodes according to the present invention;
FIG. 2 is a schematic block diagram of a CAN node of the present invention;
FIG. 3 is a flow chart of a method of operation of a CAN node of the present invention:
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
As shown in fig. 2, according to an aspect of the present invention, there is provided a CAN node comprising a controller 1, a CAN transceiver 2, a first CAN bus socket 3, a second CAN bus socket 4, a first CAN bus plug 5, a second CAN bus plug 6, a first resistor 7, a second resistor 8, a third resistor 9, and a controllable switch 10.
Referring to fig. 1, a first CAN node and an nth CAN node are terminal CAN nodes of a CAN bus, and second to nth CAN nodes-1 are intermediate CAN nodes of the CAN bus. One end of the 1 st CAN cable is connected to a second CAN bus socket 4 of a first CAN node through a second CAN bus plug 6, and the other end of the 1 st CAN cable is connected to a first CAN bus socket 3 of a second CAN node through a first CAN bus plug 5, so that the first CAN node and the second CAN node are connected with each other; one end of the 2 nd CAN cable is connected to a second CAN bus socket 4 of a second CAN node through a second CAN bus plug 6, the other end of the 2 nd CAN cable is connected to a first CAN bus socket 3 of a third CAN node through a first CAN bus plug 5, so that the first CAN node is connected to the third CAN node, … …, and so on, one end of the (N-1) th CAN cable is connected to a second CAN bus socket 4 of the (N-1) th CAN node through the second CAN bus plug 6, the other end of the (N-1) th CAN cable is connected to a first CAN bus socket 3 of the (N) th CAN node through the first CAN bus plug 5, so that the first CAN node is connected to the N-th CAN node. The first CAN-bus socket 3 of the first CAN-node being a terminal CAN-node is left empty and the second CAN-bus socket 4 of the nth CAN-node being a terminal CAN-node is left empty, where N is a positive integer.
The CAN cable includes two-core twisted-pair signal lines for transmitting CANH and CANL signals of the CAN bus, respectively.
The controller 1 is connected to the CAN transceiver 2.
Each of the first CAN bus socket 3 and the second CAN bus socket 4 includes a plurality of pins (4 pins in this embodiment), the 1 st pin of each of the first CAN bus socket 3 and the second CAN bus socket 4 is connected to the controller 1 and is connected to a positive power VCC (which is typically 3.3V) through a first resistor 7 and a second resistor 8, respectively, the 2 nd pin is grounded, the 3 rd pins of each of the first CAN bus socket 3 and the second CAN bus socket 4 are electrically connected to the CAN transceiver 2 for transmitting a CANH signal, the 4 th pins of each of the first CAN bus socket 3 and the second CAN bus socket 4 are electrically connected to the CAN transceiver 2 for transmitting a CANL signal, the 4 th pin of the first CAN bus socket 3 is further connected to the 3 rd pin of the first CAN bus socket 3 through a third resistor 9 and a controllable switch 10, and the 4 th pin of the second CAN bus socket 4 is further connected to the 3 rd pin of the second CAN bus socket 3 through a third resistor 9 and a controllable switch 10.
Each of the first CAN bus plug 5 and the second CAN bus plug 6 includes a plurality of pins (4 pins in this embodiment), pin 1 of the first CAN bus plug 5 is directly connected to pin 2 of the first CAN bus plug 5, pin 1 of the second CAN bus plug 6 is directly connected to pin 2 of the second CAN bus plug 6, pin 3 of the first CAN bus plug 5 in one CAN node is connected to pin 3 of the first CAN bus socket 3 in another CAN node for transmitting a CANH signal, pin 4 of the first CAN bus plug 5 in one CAN node is connected to pin 4 of the first CAN bus socket 3 in another CAN node for transmitting a CANL signal, pin 3 of the second CAN bus plug 6 in one CAN node is connected to pin 3 of the second CAN bus socket 4 in another CAN node for transmitting a CANH signal, and pin 4 of the second CAN bus plug 6 in one CAN node is connected to pin 4 of the second CAN bus socket 4 in another CAN node for transmitting a CANL signal. The CAN communication network comprises a CAN terminal resistor, a CAN node and a CAN node, wherein the CAN node is connected with the CAN terminal resistor automatically, and the CAN node is connected with the CAN terminal resistor automatically.
In use, when the first CAN bus plug 5 is connected to the first CAN bus socket 3, or the second CAN bus plug 6 is connected to the second CAN bus socket 4, the CAN node is used as a terminal CAN node; when the first CAN-bus plug 5 is connected to the first CAN-bus socket 3 and the second CAN-bus plug 6 is connected to the second CAN-bus socket 4, the CAN node is used as an intermediate CAN node.
More specifically, when the first CAN bus plug 5 is connected to the first CAN bus socket 3 (i.e., pins 1, 2, 3, and 4 of the first CAN bus plug 5 are connected to pins 1, 2, 3, and 4 of the first CAN bus socket 3, respectively), pin 1 of the first CAN bus socket 3 is connected to pin 2, and pin 1 of the first CAN bus socket 3 outputs a low level; when the first CAN bus socket 3 is not connected with the first CAN bus plug 5, the No. 1 pin and the No. 2 pin of the first CAN bus socket 3 are disconnected, and the No. 1 pin of the first CAN bus socket 3 outputs a high level;
similarly, when the second CAN bus plug 6 is connected to the second CAN bus socket 4, the 1 st pin of the second CAN bus socket 4 outputs a low level; when the second CAN bus plug 6 is not connected to the second CAN bus socket 4, the 1 st pin of the second CAN bus socket 4 outputs a high level.
Specifically, the first resistor 7 and the second resistor 8 have the same resistance and are both larger than 10k ohms, the third resistor 9 has a resistance of 120 ohms, and the controllable switch 10 is a MOS switch used.
The first CAN bus socket and the second CAN bus socket are identical and are both aviation sockets.
The first CAN bus plug and the second CAN bus plug are identical and are both aviation plugs.
As shown in fig. 3, according to another aspect of the present invention, there is provided an operating method of the CAN node, including the steps of:
(1) The CAN controller respectively acquires a first connection signal output from a 1 st pin of the first CAN bus socket 3 and a second connection signal output from a 1 st pin of the second CAN bus socket 4;
(2) The CAN controller judges whether the first connection signal and the second connection signal acquired in the step (1) are both high level, if so, the step (3) is carried out, otherwise, the step (4) is carried out;
(3) The CAN controller sets a CAN node where the CAN controller is located to be in a disconnection state, and then the process is ended;
(4) The CAN controller judges whether the first connection signal and the second connection signal acquired in the step (1) are both low level, if so, the step (5) is carried out, otherwise, the step (6) is carried out;
(5) The CAN controller sets the CAN node where the CAN controller is located as an intermediate CAN node, and sets the change-over switch to be in a disconnection state so as to disconnect the third resistor, and the process is finished;
(6) The CAN controller sets the CAN node where the CAN controller is located as a terminal CAN node, and sets the change-over switch to be in a closed state so as to connect the third resistor, and the process is finished.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (7)
1. A CAN node comprises a controller, a CAN transceiver, a first CAN bus socket, a second CAN bus socket, a first CAN bus plug, a second CAN bus plug, a first resistor, a second resistor, a third resistor and a controllable switch,
the controller is connected with the CAN transceiver;
the first CAN bus socket and the second CAN bus socket both comprise a plurality of pins, the 1 st pin of the first CAN bus socket and the 1 st pin of the second CAN bus socket are both connected to the controller and are respectively connected to a positive power supply VCC through a first resistor and a second resistor, and the 2 nd pin is both grounded;
the 3 rd pins of the first CAN bus socket and the second CAN bus socket are electrically connected with the CAN transceiver and are used for transmitting CANH signals;
the 4 th pins of the first CAN bus socket and the second CAN bus socket are electrically connected with the CAN transceiver and are used for transmitting CANL signals;
the 4 th pin of the first CAN bus socket is also connected to the 3 rd pin of the first CAN bus socket through a third resistor and a controllable switch, and the 4 th pin of the second CAN bus socket is also connected to the 3 rd pin of the second CAN bus socket 3 through the third resistor and the controllable switch;
when the CAN node works, when a first CAN bus plug is connected into a first CAN bus socket or a second CAN bus plug is connected into a second CAN bus socket, the CAN node is used as a terminal CAN node; when the first CAN bus plug is connected to the first CAN bus socket and the second CAN bus plug is connected to the second CAN bus socket, the CAN node is used as an intermediate CAN node.
2. The CAN node of claim 1,
the first CAN bus plug and the second CAN bus plug both comprise a plurality of pins, the 1 st pin of the first CAN bus plug is directly connected with the 2 nd pin of the first CAN bus plug, and the 1 st pin of the second CAN bus plug is directly connected with the 2 nd pin of the second CAN bus plug;
a 3 rd pin of a first CAN bus plug in one CAN node is connected to a 3 rd pin of a first CAN bus socket in another CAN node and is used for transmitting a CANH signal;
the 4 th pin of the first CAN bus plug in one CAN node is connected to the 4 th pin of the first CAN bus socket in the other CAN node and is used for transmitting a CANL signal;
a 3 rd pin of a second CAN bus plug in one CAN node is connected to a 3 rd pin of a second CAN bus socket in another CAN node and is used for transmitting a CANH signal;
pin 4 of the second CAN-bus plug in one CAN node is connected to pin 4 of the second CAN-bus socket in another CAN node for transmitting CANL signals.
3. The CAN node of claim 1 or 2,
when the first CAN bus plug is connected to the first CAN bus socket, the 1 st pin of the first CAN bus socket is connected with the 2 nd pin, and the 1 st pin of the first CAN bus socket outputs low level;
when the first CAN bus socket is not connected with the first CAN bus plug, the 1 st pin and the 2 nd pin of the first CAN bus socket are disconnected, and the 1 st pin of the first CAN bus socket outputs a high level;
when the second CAN bus plug is connected to the second CAN bus socket, the 1 st pin of the second CAN bus socket outputs low level;
and when the second CAN bus plug is not connected to the second CAN bus socket, the 1 st pin of the second CAN bus socket outputs high level.
4. The CAN node of any one of claims 1 to 3,
the resistance values of the first resistor and the second resistor are the same and are both larger than 10k ohms;
the resistance of the third resistor is 120 ohms;
the controllable switches are MOS switches.
5. The CAN node of claim 1,
the first CAN bus socket and the second CAN bus socket are identical and adopt aviation sockets.
The first CAN bus plug and the second CAN bus plug are identical and are both aviation plugs.
6. A method of operating a CAN node according to any of claims 1 to 5, comprising the steps of:
(1) The CAN controller respectively acquires a first connection signal output from a 1 st pin of a first CAN bus socket and a second connection signal output from a 1 st pin of a second CAN bus socket;
(2) The CAN controller judges whether the first connection signal and the second connection signal acquired in the step (1) are both high level, if so, the step (3) is carried out, otherwise, the step (4) is carried out;
(3) The CAN controller sets a CAN node where the CAN controller is located to be in a disconnection state, and then the process is ended;
(4) The CAN controller judges whether the first connection signal and the second connection signal acquired in the step (1) are both low level, if so, the step (5) is carried out, otherwise, the step (6) is carried out;
(5) The CAN controller sets the CAN node where the CAN controller is located as an intermediate CAN node, and sets the change-over switch to be in a disconnection state so as to disconnect the third resistor, and the process is finished;
(6) The CAN controller sets the CAN node where the CAN controller is located as a terminal CAN node, and sets the change-over switch to be in a closed state so as to connect the third resistor, and the process is finished.
7. A CAN bus comprising N CAN nodes according to any one of claims 1 to 5,
the first CAN node and the Nth CAN node are used as terminal CAN nodes of a CAN bus, and the second CAN node to the Nth CAN node-1 are used as middle CAN nodes of the CAN bus;
one end of the 1 st CAN cable is connected to a second CAN bus socket of the first CAN node through a second CAN bus plug of the first CAN node, and the other end of the 1 st CAN cable is connected to a first CAN bus socket of the second CAN node through a first CAN bus plug of the second CAN node, so that the first CAN node and the second CAN node are connected with each other;
one end of the 2 nd CAN cable is connected to a second CAN bus socket of the second CAN node through a second CAN bus plug of the second CAN node, and the other end of the 2 nd CAN cable is connected to a first CAN bus socket of the third CAN node through a first CAN bus plug of the third CAN node, so that the first CAN node is connected with the third CAN node, … …, and so on;
one end of the (N-1) th CAN cable is connected to a second CAN bus socket of the (N-1) th CAN node through a second CAN bus plug of the (N-1) th CAN node, and the other end of the (N-1) th CAN cable is connected to a first CAN bus socket of the (N) th CAN node through a first CAN bus plug of the (N) th CAN node, so that the first CAN node and the Nth CAN node are connected with each other;
a first CAN-bus socket of a first CAN-node as a terminal CAN-node is left empty, and a second CAN-bus socket of an nth CAN-node as a terminal CAN-node is left empty, wherein N is a positive integer.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| 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 |
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