Worked on the tiiuae/px4-firmware repository to enhance hardware validation by developing an improved UART loopback test supporting a chain of up to three UART devices. This involved implementing the chain_loopback test, refactoring the existing loopback framework to accommodate multiple UARTs in a chained configuration, and introducing a set_port command for configuring UART ports to 115200 baud. The work focused on driver development and embedded systems, utilizing C++ for system programming and testing. These enhancements increased test coverage, configurability, and debugging efficiency for UART-based verification, contributing to more robust hardware validation processes within the firmware project.