As the functions of automobiles continue to increase and become more intelligent, the data exchange and communication between onboard electronic devices have become increasingly important. To ensure the reliability and stability of these systems in practical applications, it is necessary to manually simulate the testing and verification of ECUs with erroneous bus data packets. This paper designs a vehicular bus signal simulation device that can simulate the generation of CAN, LIN, FlexRay, CXPI, and SENT bus signals and their fault data packets. The hardware part of the device consists of an arbitrary waveform generator and an upper computer, while the software part uses QT to design the user interface and C++ to write the programmable software. Finally, experiments have verified the performance and accuracy of the simulation device. The waveforms captured by the digital storage oscilloscope are consistent with the expected input parameters, proving the effectiveness of the device. This device has significant application value in the development, teaching, and training of automotive electronic systems, capable of reducing the reliance on real-vehicle testing, and reducing test costs and time

Vehicle bus, Signal Simulation, QT