Interface definition

DSU7 is a new interface for cuav naming, including fmu swd and uart7 interfaces. When V5 runs PX4 firmware,uart7 is used as the DEBUG interface; when running ArduPilot firmware; uart7 is used as the communication serial port and usb is used to debug the output.

Warning The RCIN interface is limited to powering the remote control and cannot be connected to any power/load.