Method for transmitting Modbus RTU protocol in wide area network

Abstract

The invention relates to the technical field of Internet of Things sensing equipment communication, in particular to a method for transmitting a Modbus RTU protocol in a wide area network, which is applied to a network in which a slave station is connected with a master station through a communication module, and comprises the steps that the communication module generates a self-defined registration message and sends the registration message to the master station, and the registration message comprises setting information of the communication module; the communication module is connected with a managed slave station address; after receiving the registration message, the master station records the setting information of the communication module and the address of the slave station connected and managed by the communication module, and establishes a link; and the master station and the slave station carry out transmission and interaction of the Modbus RTU protocol through the established link. According to the method, the Modbus RTU protocol is transmitted in the wide area network, the whole process is not limited by the fact that the slave station must have a fixed IP address, the protocol conversion process and a conversion module are omitted, the monitoring function cost of the Internet of Things sensing equipment is reduced, and the monitoring efficiency is improved.

Description

technical field [0001] The invention relates to the technical field of Internet of Things sensing device communication, in particular to a method for transmitting the Modbus RTU protocol in a wide area network. Background technique [0002] Modbus is the world's first real bus protocol for industrial field. The Modbus protocol is a common language applied to control devices. Through the Modbus protocol, communication between controllers and between controllers and other devices via a network (such as Ethernet) can be realized. At present, the Modbus protocol has become a general industrial standard, and the control devices produced by different manufacturers are connected into an industrial network through the Modbus protocol for centralized monitoring. The ModBus network has only one host, and all communications are initiated by the host. [0003] The Modbus protocol includes the Modbus TCP protocol and the Modbus RTU protocol. Generally, the asynchronous serial transmiss...

AI Technical Summary

Problems solved by technology

The conversion module is mainly to convert the Modbus RTU protocol to the Modbus TCP protocol, so that it can be transmitted in the Ethernet. Because the Modbus TCP protocol requires the master station to actively establish a TCP link to the slave station, and the existing slave station generally does not have a fixed IP, so the Modbus TCP protocol is only suitable for transmission in the LAN. If it is to be transmitted in the WAN, that is, to transmit the ModbusTCP data packet to the IoT management platform through the WAN, you need to add a VPN gateway device to establish a VPN network. The fixed IP address is assigned to the station, so as to realize the transmission of the Modbus TCP protocol in the WAN, but adding VPN gateway equipment not only increases the cost, but also increases the processing time and reduces the efficiency of monitoring

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