I'm trying to send MIDI over USB through a host shield, and it works if I use the exact command in the example file (big surprise):
but I need to replace the x02 with a variable. I've tried everything I can think of, but the bottom line is that I don't understand why the message itself is in quotations, or how to make a portion of the message be a variable. All my attempts have either not compiled or not worked.
Any advice would be hugely appreciated.