Modbus is an open serial communication protocol. It was developed in 1979 for use with programmable logic controller (PLC) devices, and is now widely used to connect many types of industrial electronic devices connected to various types of networks.
The most widely used protocol in industrial automation (with the exception of local enterprises). Modbus is very popular. This is a fairly simple and intuitive device to use with standard serial communication. In a Modbus network, each device looks into the network as a set of coils (bits) and registers. The wizard reads and writes these coils and registers using a very simple and concise set of instructions. Communication moves only in one direction at a time.
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