Communication from H7 plus to Arduino

I am trying to communicate information from the openMV camera to Arduino, but I don’t know the best method of communication. I was thinking about just setting certain pins to high and low, but I can’t communicate as much information that way. I tried UART but it seems to be a very slow form of communication from what I noticed. Can someone tell me the best way to send the information about the position of a blob to an Arduino device? and provide me a link where I can learn more about this method of communication?

You should use the RPC library: