Connecting raspberry pi4 to cuav x7+

how to send data through cuav x7 + to raspberry using uart through functions

I mean I need to transmit rs signals to cuav via uart for raspberry Pi to process it and also I need to output the image.

Maybe someone knows some good guides or has already done it himself?
thanks in advance for your help

There’s a section on the ArduPilot wiki: Communicating with Raspberry Pi via MAVLink — Dev documentation