I'm planning to use my old fbv4 pedal to make a MIDI controller. I have 2 options. Either I need to throw the present board on it and replace it something like arduino which I will only need the buttons and case

OR

Maybe it is already sending midi messages. I can re-map them to suit with other midi devices (using arduino).

If it is midi, can someone explain me the conversion between JR45 and Midi plugs?