This is a fully functioning PRU RProc Messaging example that works on my BBB revision C board.
The thing that makes this solution unique is as of this date of writing, I could not find a ready to compile and ready to run example that had both the application code and the PRU code together. When your struggling understanding the UIO vs. Remote Proc architectures and you don’t know what goes with what, this will save some time for you.
git clone https://gitlab.com/brucechidester/pru-messaging-example.git
or browse to: