C-UART Interface Example is a reference implementation for MAVLink communication over UART on Unix-like systems that enables offboard computers to interact with Pixhawk autopilots.
The tool addresses the need to establish reliable serial communication between a Pixhawk flight controller and an external computer. It demonstrates how to receive and send individual MAVLink messages over a UART connection, which is preferred over USB for flight-critical operations due to the simpler and more trusted driver implementation. The example handles port detection, message serialization, and the basic send-receive loop required for autopilot communication.
This project suits developers building offboard control systems, companion computer applications, or learning MAVLink protocol integration. It works with Pixhawk hardware connected via USB programming cable, Telemetry Radio on TELEM1 or TELEM2 ports, or FTDI developer cables on various serial ports. The example is intentionally minimal, showing only one receive and one send operation, making it suitable as a starting point for custom applications rather than a complete communication framework. Developers can extend it by modifying message types or adding additional send-receive cycles.
The project maintains a straightforward, focused codebase with clear documentation of hardware setup and port mappings for different Pixhawk UART configurations. The README provides specific guidance on device enumeration, connection options including Telemetry Radio and FTDI cable alternatives, and integration with the PX4 simulator. The exploration section outlines concrete next steps for extending the example, such as modifying message data types or adding NuttX shell debugging output.
