Nintendo_Fan

I have been unable to successfully set up a Switch Pro Controller on Retro Arch or Launchbox. Everytime I boot up a game, and go into the menu to change controls, it won't let me. It doesn't let me map the buttons at all. I was playing an N64 game and it wouldn't let me map the left stick to the control stick or the right stick to the C-Buttons. I can't find any tutorials on youtube or in the playlist, so I was hoping someone here could please help?

I have a pro controller connected to my laptop (bluetooth) and am trying to play mario 64. The only problem is that a and b are switched and my left stick does nothing. Any idea how to map it so that a and b are right and that the left stick works?