Unfortunately rx0 is on the ftdi that I use to connect to my PC.
That's the point
I also have a Arduino Uno that I uploaded a sketch to and I ran fine so I'm assuming it's working ok. Does this loop test tell me more about my Uno that I would like to know? I have a reset pin and a tx1 and rx0 on the Digital pins. But again, not to sound stupid but what would be a terminal program and how do you hook up a serial port to test with.
The loopback test is to verify operation of the USB/serial chip. If it works there is no need for it