CN113395187A - 485 bus based communication enhancement method and system - Google Patents
485 bus based communication enhancement method and system Download PDFInfo
- Publication number
- CN113395187A CN113395187A CN202110584102.2A CN202110584102A CN113395187A CN 113395187 A CN113395187 A CN 113395187A CN 202110584102 A CN202110584102 A CN 202110584102A CN 113395187 A CN113395187 A CN 113395187A
- Authority
- CN
- China
- Prior art keywords
- bus
- chip microcomputer
- single chip
- monitoring
- communication
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- 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
- H04L43/16—Threshold monitoring
-
- 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
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L47/00—Traffic control in data switching networks
- H04L47/10—Flow control; Congestion control
-
- 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
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Small-Scale Networks (AREA)
Abstract
The invention relates to a communication enhancement method and a system based on a 485 bus, wherein the method monitors signals on the 485 bus by utilizing a singlechip within first monitoring time; the state of the bus is judged by judging whether the signal is interrupted or not, and the anti-collision algorithm is adopted to update the monitoring time when the bus is determined to be in the busy state, so that the problems of communication collision and signal interference when the device is changed from passive communication to active communication are solved, the application of the 485 bus in a communication scene with high real-time requirement is realized, and the accuracy and the efficiency of communication are improved.
Description
Technical Field
The invention relates to the technical field of communication, in particular to a communication enhancement method and system based on a 485 bus.
Background
The 485 bus is widely applied to various industrial control fields and networking communication modes of various sensing acquisition systems. The method adopts a half-duplex polling working mode to support multipoint data communication and can realize one-to-one or one-to-many networking. The 485 bus can be provided with 128 nodes, the ideal communication distance is 1200 meters, and the 485 bus is a common economic traditional industrial bus.
The traditional 485 bus is generally used for a master-slave communication transmission network, is not suitable for being applied to a scene with high communication real-time response requirements, and has poor communication effect.
Therefore, a 485 bus-based communication enhancement method and system are needed to meet the requirement of real-time communication.
Disclosure of Invention
The invention aims to provide a communication enhancement method and a communication enhancement system based on a 485 bus, which can apply the 485 bus to communication scenes with high real-time requirements, such as real-time response and active information reporting requirements of a terminal, and can enhance the real-time performance and efficiency of communication.
In order to achieve the purpose, the invention provides the following scheme:
a485 bus-based communication enhancement method comprises the following steps:
monitoring a signal on a 485 bus by using a single chip microcomputer within a first monitoring time;
judging whether the signal is interrupted;
if the signal is not interrupted, determining that the bus is in an idle state, and after the first monitoring time, enabling the single chip microcomputer to start to send data to the 485 bus until the data is sent completely;
if the received signal is interrupted, determining that the 485 bus is in a busy state, adding 1 to the number of collisions, and calculating second monitoring time by adopting an anti-collision algorithm;
judging whether the number of times of conflict is greater than a set threshold value;
if the number of times of conflict is smaller than the set threshold value, enabling the second monitoring time to be equal to the first monitoring time, and judging to return to the step of monitoring the signal on the 485 bus by using the single chip microcomputer within the first monitoring time;
and if the number of times of collision is greater than the set threshold value, stopping the single chip microcomputer from sending data to the 485 bus.
A 485-bus based communication enhancement system, comprising:
the monitoring module is used for monitoring signals on the 485 bus by utilizing the single chip microcomputer within first monitoring time;
the signal interruption judging module is used for judging whether the signal is interrupted; if the signal is not interrupted, determining that the bus is in an idle state, and after the first monitoring time, enabling the single chip microcomputer to start to send data to the 485 bus until the data is sent completely; if the received signal is interrupted, determining that the 485 bus is in a busy state, adding 1 to the number of collisions, and calculating second monitoring time by adopting an anti-collision algorithm;
the conflict frequency judging module is used for judging whether the conflict frequency is greater than a set threshold value or not; if the number of times of conflict is smaller than the set threshold value, enabling the second monitoring time to be equal to the first monitoring time, and judging to return to the step of monitoring the signal on the 485 bus by using the single chip microcomputer within the first monitoring time; and if the number of times of collision is greater than the set threshold value, the single chip microcomputer stops sending data to the 485 bus.
According to the specific embodiment provided by the invention, the invention discloses the following technical effects:
according to the communication enhancement method and system based on the 485 bus, the state of the 485 bus is actively monitored through the single chip microcomputer (namely the slave), and the communication is selectively carried out with the upper computer (namely the host) according to the state of the 485 bus, so that communication blockage can be avoided, communication time is staggered, the problems of communication conflict and signal interference when the device is changed from passive communication to active communication are solved, the real-time performance and the accuracy of the active communication of the device are guaranteed, the host can timely acquire device information, and the communication efficiency is improved; by setting hardware equipment, such as setting polling time for a host, data sending time for a slave and the like, switching between passive communication and active communication can be realized without changing hardware.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
Fig. 1 is a flowchart of a 485 bus based communication enhancement method according to embodiment 1 of the present invention;
fig. 2 is a hardware circuit connection diagram provided in embodiment 1 of the present invention;
fig. 3 is a block diagram of a communication enhancement system based on a 485 bus according to embodiment 1 of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention aims to provide a communication enhancement method and a communication enhancement system based on a 485 bus, which can apply the 485 bus to communication scenes with high real-time requirements, such as real-time response and active information reporting requirements of a terminal, and can enhance the real-time performance and efficiency of communication.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
Example 1:
in a master-slave communication transmission network based on a 485 bus in the prior art, a host is generally required to send a command to a slave, and the slave receives the command and then returns data to the host through the 485 bus. Under the condition, a plurality of hosts can send data to the 485 bus at the same time to cause communication blockage, and data signals received by the hosts are disordered and delayed, so that the real-time performance of the signals and the accuracy and efficiency of communication cannot be ensured, namely the 485 bus in the prior art cannot meet the requirements of the accuracy, the real-time performance and the efficiency of active communication. Therefore, referring to fig. 1, on the basis of not changing the original passive communication, the present invention provides a communication enhancement method based on 485 bus, including:
step S1: monitoring a signal on a 485 bus by using a single chip microcomputer within first monitoring time every a preset period;
step S2: judging whether the signal is interrupted;
if the signal is not interrupted, determining that the bus is in an idle state, and after the first monitoring time, enabling the single chip microcomputer to start to send data to the 485 bus until the data is sent;
if the received signal is interrupted, determining that the 485 bus is in a busy state, adding 1 to the number of collisions, and calculating second monitoring time by adopting an anti-collision algorithm;
step S3: judging whether the number of times of collision is greater than a set threshold value, and preferentially setting the collision threshold value to be 8;
if the number of times of conflict is smaller than a set threshold value, enabling the first monitoring time to be equal to the second monitoring time, and judging to return to the step of monitoring the signal on the 485 bus by utilizing the single chip microcomputer within the first monitoring time;
and if the number of times of conflict is greater than the set threshold value, the single chip microcomputer stops sending the data to the 485 bus.
In order to realize the monitoring of the bus by the single chip microcomputer, as shown in fig. 2, a receiving pin RXD3 of the communication chip is simultaneously connected to a serial port receiving pin of the single chip microcomputer and an external interrupt pin of the single chip microcomputer, TXD3 is connected to a serial port sending pin of the single chip microcomputer, DE1 is connected to a control pin of the single chip microcomputer, 485-B and 485-a are connected to an external communication bus, the external interrupt pin of the single chip microcomputer monitors signals on the 485 bus, namely, the external interrupt pin is used for receiving data on the bus through the RXD3 terminal and judging whether the bus is idle, the data is sent to the bus through the TXD3 when the bus is idle, and DE1 is high level and allows the data to be sent to the bus.
As an optional implementation manner, the calculating the second listening time by using an anti-collision algorithm specifically includes:
Cmax＝2C
N1＝N mod Cmax
T＝N1*(t1+t2)
wherein C represents the number of collisions, N represents a random number obtained by using a timing self-increment count in the single chip as a random factor, T1 represents the transmission delay of one frame of data, T2 represents the 485 bus transmission delay, and T represents the second listening time.
According to the invention, through a special hardware technology (connecting an interrupt pin of a single chip microcomputer and a receiving pin of a communication chip) and a software algorithm (the single chip microcomputer, namely a slave computer monitors the state of a bus, data is selectively sent according to the state of the 485 bus, particularly, an anti-collision algorithm is adopted when the 485 bus is determined to be in a busy state, the slave computer sends data by staggered time, the waiting time of the slave computer is the second monitoring time), the phenomenon of communication collision is effectively prevented, the accuracy and efficiency of communication are improved, the real-time performance of communication is ensured, and the traditional 485 bus is applied to a communication scene with high real-time requirement.
As an optional implementation manner, in order to further improve the accuracy of communication delivery, the invention also judges whether the single chip microcomputer receives the reply of the upper computer or not after the single chip microcomputer starts to send data to the 485 bus until the data is sent;
if the single chip microcomputer receives the reply of the upper computer, the communication between the single chip microcomputer and the upper computer is finished;
if the singlechip does not receive the reply of the upper computer, the retransmission times is added by 1;
judging the retransmission times and the size of a set threshold;
if the retransmission times are less than the set threshold value, returning to the step of monitoring the signal on the 485 bus by using the single chip microcomputer within the first monitoring time after a period of time, and enabling the single chip microcomputer to resend the data to the upper computer;
if the retransmission times is larger than the set threshold value, the communication between the single chip microcomputer and the upper computer is ended.
In an alternative manner, the specific calculation method at intervals is as follows:
t3＝(t4+R(mod)D)*5
where t3 denotes an interval time, t4 denotes a basic communication setup time, R denotes a random number, and D denotes the number of devices on the 485 bus.
Further, the basic communication establishment time represented by t4 is the interval time between two times of communication between the upper computer and the device, and can be set to 60 or adjusted according to the actual line; r is obtained according to the random factor of the self-increment count of the single chip microcomputer.
The invention realizes the application of the 485 bus in active communication, can also set the polling time of a host, the data sending time of a slave and the like, and improves the problems of communication blockage and low efficiency of the 485 bus in passive communication. The invention thus enables switching between passive and active communication without the need to modify the hardware.
Example 2:
referring to fig. 3, the present invention provides a 485 bus based communication enhancement system, including:
the monitoring module M1 is used for monitoring signals on the 485 bus by using the single chip microcomputer within a first monitoring time;
a signal interruption judging module M2, configured to judge whether the signal is interrupted; if the signal is not interrupted, determining that the bus is in an idle state, and after the first monitoring time, enabling the single chip microcomputer to start to send data to the 485 bus until the data is sent completely; if the received signal is interrupted, determining that the 485 bus is in a busy state, adding 1 to the number of collisions, and calculating second monitoring time by adopting an anti-collision algorithm;
a conflict number judging module M3, configured to judge whether the conflict number is greater than a set threshold; if the number of times of conflict is smaller than the set threshold value, enabling the second monitoring time to be equal to the first monitoring time, and judging to return to the step of monitoring the signal on the 485 bus by using the single chip microcomputer within the first monitoring time; and if the number of times of collision is greater than the set threshold value, the single chip microcomputer stops sending data to the 485 bus.
As an optional implementation manner, after the signal interruption determining module M2, the method further includes:
the reply judging module is used for judging whether the singlechip receives the reply of the upper computer; if the single chip microcomputer receives the reply of the upper computer, the communication between the single chip microcomputer and the upper computer is finished; if the single chip microcomputer does not receive the reply of the upper computer, the retransmission times are added by 1;
the retransmission number judging module is used for judging the retransmission number and the size of a set threshold; if the retransmission times are smaller than a set threshold value, returning to the step of monitoring the signal on the 485 bus by using the single chip microcomputer within the first monitoring time after a period of time, and enabling the single chip microcomputer to resend the data to the upper computer; and if the retransmission times are larger than a set threshold value, finishing the communication between the singlechip and the upper computer.
The emphasis of each embodiment in the present specification is on the difference from the other embodiments, and the same and similar parts among the various embodiments may be referred to each other. For the system disclosed by the embodiment, the description is relatively simple because the system corresponds to the method disclosed by the embodiment, and the relevant points can be referred to the method part for description.
The principles and embodiments of the present invention have been described herein using specific examples, which are provided only to help understand the method and the core concept of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.
Claims (8)
1. A communication enhancement method based on 485 bus is characterized by comprising the following steps:
monitoring a signal on a 485 bus by using a single chip microcomputer within a first monitoring time;
judging whether the signal is interrupted;
if the signal is not interrupted, determining that the bus is in an idle state, and after the first monitoring time, enabling the single chip microcomputer to start to send data to the 485 bus until the data is sent completely;
if the received signal is interrupted, determining that the 485 bus is in a busy state, adding 1 to the number of collisions, and calculating second monitoring time by adopting an anti-collision algorithm;
judging whether the number of times of conflict is greater than a set threshold value;
if the number of times of conflict is smaller than the set threshold value, enabling the first monitoring time to be equal to the second monitoring time, and judging to return to the step of monitoring the signal on the 485 bus by using the single chip microcomputer within the first monitoring time;
and if the number of times of collision is greater than the set threshold value, the single chip microcomputer stops sending data to the 485 bus.
2. The 485-bus-based communication enhancement method according to claim 1, wherein the single-chip microcomputer is used for monitoring the signal on the 485 bus in the first monitoring time every predetermined period.
3. The communication enhancement method according to claim 1, wherein the monitoring of the signal on the 485 bus by the single chip specifically comprises: and connecting an external interrupt pin of the singlechip with a receiving pin of the communication chip, and monitoring a signal on the 485 bus by using the external interrupt pin.
4. The 485-bus-based communication enhancement method according to claim 1, wherein the calculating the second listening time by using an anti-collision algorithm specifically comprises:
Cmax＝2C
N1＝N mod Cmax
T＝N1*(t1+t2)
wherein C denotes the number of collisions, N denotes a random number, T1 denotes a transmission delay of one frame data, T2 denotes a 485 bus transmission delay, and T denotes the second listening time.
5. The communication enhancement method based on the 485 bus of claim 1, wherein after the single chip microcomputer starts to send data to the 485 bus until the data is sent, whether the single chip microcomputer receives a reply of an upper computer is judged;
if the single chip microcomputer receives the reply of the upper computer, the communication between the single chip microcomputer and the upper computer is finished;
if the single chip microcomputer does not receive the reply of the upper computer, the retransmission times are added by 1;
judging the retransmission times and the size of a set threshold;
if the retransmission times are smaller than a set threshold value, returning to the step of monitoring the signal on the 485 bus by using the single chip microcomputer within the first monitoring time after a period of time, and enabling the single chip microcomputer to resend the data to the upper computer;
and if the retransmission times are larger than a set threshold value, finishing the communication between the singlechip and the upper computer.
6. The 485-bus-based communication enhancement method according to claim 1, wherein the specific calculation method for the interval of time includes:
t3＝(t4+R mod D)*5
where t3 denotes an interval time, t4 denotes a basic communication setup time, R denotes a random number, and D denotes the number of devices on the 485 bus.
7. A 485-bus-based communication enhancement system, comprising:
the monitoring module is used for monitoring signals on the 485 bus by utilizing the single chip microcomputer within first monitoring time;
the signal interruption judging module is used for judging whether the signal is interrupted; if the signal is not interrupted, determining that the bus is in an idle state, and after the first monitoring time, enabling the single chip microcomputer to start to send data to the 485 bus until the data is sent completely; if the received signal is interrupted, determining that the 485 bus is in a busy state, adding 1 to the number of collisions, and calculating second monitoring time by adopting an anti-collision algorithm;
the conflict frequency judging module is used for judging whether the conflict frequency is greater than a set threshold value or not; if the number of times of conflict is smaller than the set threshold value, enabling the first monitoring time to be equal to the second monitoring time, and judging to return to the step of monitoring the signal on the 485 bus by using the single chip microcomputer within the first monitoring time; and if the number of times of collision is greater than the set threshold value, the single chip microcomputer stops sending data to the 485 bus.
8. The 485-bus based communication enhancement system according to claim 7, further comprising, after said signal interruption determining module:
the reply judging module is used for judging whether the singlechip receives the reply of the upper computer; if the single chip microcomputer receives the reply of the upper computer, the communication between the single chip microcomputer and the upper computer is finished; if the single chip microcomputer does not receive the reply of the upper computer, the retransmission times are added by 1;
the retransmission number judging module is used for judging the retransmission number and the size of a set threshold; if the retransmission times are smaller than a set threshold value, returning to the step of monitoring the signal on the 485 bus by using the single chip microcomputer within the first monitoring time after a period of time, and enabling the single chip microcomputer to resend the data to the upper computer; and if the retransmission times are larger than a set threshold value, finishing the communication between the singlechip and the upper computer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110584102.2A CN113395187B (en) | 2021-05-27 | 2021-05-27 | 485 bus based communication enhancement method and system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110584102.2A CN113395187B (en) | 2021-05-27 | 2021-05-27 | 485 bus based communication enhancement method and system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113395187A true CN113395187A (en) | 2021-09-14 |
| CN113395187B CN113395187B (en) | 2022-05-20 |
Family
ID=77619299
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110584102.2A Active CN113395187B (en) | 2021-05-27 | 2021-05-27 | 485 bus based communication enhancement method and system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113395187B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1997023976A1 (en) * | 1995-12-22 | 1997-07-03 | Digital Equipment Corporation | Method and apparatus in network adapter for automatic retransmission of packets |
| CN202041950U (en) * | 2010-12-30 | 2011-11-16 | Tcl集团股份有限公司 | Anti-collision controller for RS485 bus |
| CN103746889A (en) * | 2013-06-09 | 2014-04-23 | 国家电网公司 | Half-competition model RS-485 bus multimaster communication system and working method thereof |
| CN103841279A (en) * | 2014-03-25 | 2014-06-04 | 东南大学 | Bus-based multi-party communication digital telephone system |
| WO2017000411A1 (en) * | 2015-06-30 | 2017-01-05 | 宇龙计算机通信科技(深圳)有限公司 | Collision avoidance method and apparatus for use in unlicensed frequency band |
| CN112231260A (en) * | 2020-10-21 | 2021-01-15 | 中煤科工集团重庆研究院有限公司 | Preemptive multi-master RS485 bus communication method based on dynamic priority |
-
2021
- 2021-05-27 CN CN202110584102.2A patent/CN113395187B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1997023976A1 (en) * | 1995-12-22 | 1997-07-03 | Digital Equipment Corporation | Method and apparatus in network adapter for automatic retransmission of packets |
| CN202041950U (en) * | 2010-12-30 | 2011-11-16 | Tcl集团股份有限公司 | Anti-collision controller for RS485 bus |
| CN103746889A (en) * | 2013-06-09 | 2014-04-23 | 国家电网公司 | Half-competition model RS-485 bus multimaster communication system and working method thereof |
| CN103841279A (en) * | 2014-03-25 | 2014-06-04 | 东南大学 | Bus-based multi-party communication digital telephone system |
| WO2017000411A1 (en) * | 2015-06-30 | 2017-01-05 | 宇龙计算机通信科技(深圳)有限公司 | Collision avoidance method and apparatus for use in unlicensed frequency band |
| CN112231260A (en) * | 2020-10-21 | 2021-01-15 | 中煤科工集团重庆研究院有限公司 | Preemptive multi-master RS485 bus communication method based on dynamic priority |
Non-Patent Citations (2)
| Title |
|---|
| 柴晓东: "以太网多点接入控制技术", 《濮阳职业技术学院学报》 * |
| 段骞: "在RS485总线上用冲突检测方式实现对等网数据传输", 《微型机与应用》 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113395187B (en) | 2022-05-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108733604B (en) | 485 bus intelligent expansion method and device based on modbus communication protocol | |
| US5841778A (en) | System for adaptive backoff mechanisms in CSMA/CD networks | |
| KR101238466B1 (en) | Adaptive polling for bursty wireless data traffic | |
| US20010024423A1 (en) | Method and apparatus for the addition and removal of nodes from a common interconnect | |
| CN104317765A (en) | Serial communication based one-to-many communication system and implementation method | |
| CN103001888B (en) | A kind of transmission method of real time data and node device | |
| CN107622032B (en) | Three-wire expansion method and circuit of I2C bus | |
| KR100232237B1 (en) | Lan interfacing apparatus and method | |
| JP2000196602A (en) | Multiple access method in radio communication | |
| CN210324188U (en) | Integrated circuit bus IIC master-slave competition automatic switching equipment and system thereof | |
| US7206882B2 (en) | Triggered communication network for CANOpen networks | |
| CN113726592B (en) | Transmission delay test method, system and related components of edge server | |
| US6229807B1 (en) | Process of monitoring the activity status of terminals in a digital communication system | |
| CN113395187B (en) | 485 bus based communication enhancement method and system | |
| CN113315668B (en) | Method, node device and storage medium for adaptively adjusting network configuration | |
| CN107357756A (en) | The system that more equipment carry out IIC communications under holotype | |
| CN109800201B (en) | Driving method for RS485 real-time receiving and transmitting control based on linux | |
| US20100303055A1 (en) | Method for Assigning Data Messages to Time Slots in a Wireless Data Bus System Having Hidden Subscribers | |
| CN107809765B (en) | Equipment networking system and communication method based on same | |
| CN105141483A (en) | Multi-node network minimum communication interval measurement method based on CAN bus | |
| CN110855540B (en) | 485 multi-master communication method and system based on single-ring network | |
| CN204945691U (en) | A kind of C4 bus | |
| CN105357093A (en) | Bus terminal device communication protocol automatic identification conversion device and control method | |
| CN112769707B (en) | Method, device and system for preventing congestion in Internet of things | |
| CN115484219B (en) | Method, equipment and medium for avoiding port association of domestic SRIO exchange chip |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |