For the key backlighting function module, the LIN signal is sent for lighting and detection; for the physical keys, the key action test is performed by detecting the key signals.After the BabyLin is powered on, the host computer sends ASCII string commands to realize the backlight of each physical key to light up successfully.To operate the steering wheel's keys, you can send operation commands through the host computer software. The key detection is done according to the return value.