DO-254/CTS is a fully customized hardware and software platform that augments target board testing to increase verification coverage by test and satisfy the verification objectives of DO-254/ED-80. The target design runs at-speed in the target device mounted on the custom daughter board. The simulation testbench is used as test vectors to enable requirements-based testing with 100% FPGA pin-level controllability and visibility necessary to implement normal range and abnormal range tests. The FPGA testing results are captured at-speed and displayed using a simulator waveform viewer for advanced analysis and documentation.