Modbus RTU

Modbus RTU (Remote Terminal Unit) is a serial communication protocol designed for connecting industrial electronic devices. It operates over RS-485, RS-422, and RS-232 lines, enabling devices to communicate with each other through a master-slave architecture. The communication principles of Modbus RTU involve data packets called frames, which consist of an address field, function code, data, and an error-checking field. This frame structure ensures data integrity and reliability, making it suitable for various industrial applications where timely and accurate data exchange is critical.

The communication process in Modbus RTU follows a master-slave model, where a single master device controls multiple slave devices. Each device on the network has a unique address, enabling the master to direct commands and requests to specific devices. The master initiates communication by sending a request frame to a slave, which then processes the request and responds accordingly. Error checking, typically using Cyclic Redundancy Check (CRC), ensures the accuracy of the transmitted data. This methodical approach to communication helps in maintaining system integrity and preventing data corruption.