How to upload a file onto IP camera via serial UART conection

Make sure you have sx installed on your PC. If not, run sudo apt install lrzsz to install it.

Place the uploading file into your home directory. From the home directory, run screen 115200 /dev/ttyUSB0 and sign in into Linux shell.

On the camera:

cd /tmp
rx <name of the file on pc>

press Ctrl-a, then :, and run

exec !! sx <name to save the file on camera>