I'm using Ubuntu 24.04 noble armbian distribution, the branch I used for ffmpeg is https://code.ffmpeg.org/Kwiboo/FFmpeg/src/branch/v4l2request-v3 The ffmpeg included in the distribution does not matter, but regardless it is version 6.1.1. The mpv is built against the locally compiled ffmpeg with libplacebo from https://code.videolan.org/videolan/libplacebo.git

@Nick A once again you're a savior, thank you very much!

@Mohammad Adel can find the wifi chip on the board? Also Ethernet.

@Thur_Wander you don’t need 3.3v. Normally there’s a ground. You’ll need to find a ground. Maybe the outer surface of the usb port. Remember, the RX and TX have to be crossed. X

@Octavio Cuatrochio where did you put the 3.3V and GND? you only showed TXD and RXD