Design and Implementation of Modbus RTU/TCP to Profibus Gateway Using Raspberry Pi

Communication is an essential aspect of increasing productivity and efficiency in industrial automation. During the past decades, a large number of fieldbus protocols have been developed due to the wide variety of application areas and demand for different features and properties. Among other protocols, Modbus is still one of the most popular fieldbuses for interconnecting intelligent field devices. However, many control systems (e.g., industrial PCs or PLCs) communicate with field devices via Profibus.In this paper, a Modbus RTU/TCP to Profibus slave gateway is designed to solve the problem of incompatibility between these two protocols. The proposed gateway consists of a Raspberry Pi and the intelligent communication chip VPC3+S. The Raspberry Pi manages the functionality of the whole system and controls the Modbus communication, while the VPC3+S handles the Profibus-DP slave protocol. The obtained experimental results of Modbus and Profibus communication prove the proper operation of the proposed gateway.