Design and Implementation of an Embedded Interface for I²C to Modbus TCP/RTU Integration

This paper presents the development of an embedded communication interface that integrates devices using different protocols: I²C, which is widely adopted in sensors and embedded systems, and Modbus TCP/RTU, which is widely used in industrial programmable logic controllers (PLCs). This study focuses on an automation scenario involving SMT (surface mount technology) lines where industrial robots handle printed circuit boards (PCBs). In this application, TF-Luna LiDAR sensors operate via the I²C protocol to provide accurate distance measurements that guide the movements of the robotic arms. However, these sensors are not natively compatible with most PLC models, which communicate via Modbus or other protocols.
To address this incompatibility, this study proposes developing an embedded interface board that can act as a bridge between the two protocols by converting and forwarding the collected information. The interface can read multiple I²C sensors, organize the data, and make it available to the PLC via Modbus RTU or TCP, depending on the industrial network configuration. This solution contributes to precise synchronization between sensors and actuators, improves production process efficiency, and reinforces the interoperability and flexibility principles required by Industry 4.0. It also makes device interconnectivity more accessible. The proposed approach also enables modular expansion and use in various architectures, as well as greater reliability in real-time communication in industrial environments.