Live controller viewer for Nintendo consoles as well as many other retro consoles and computers. Includes viewer application for Windows, and Arduino sketch for hardware interface.
Workaround: You have to disable hotkeys in the Super NT menu, but the option appears hidden in newer firmwares. However it can still be toggled. If you scroll 1 past the "Cancel Key" menu entry in the hotkey menu you will get a warning about shutting of the menu hot key. Hit 'Y' or whatever your confirm key is set to exactly once then back out of the menu to your game. You should be set. The main downside of this, besides not being able to enter the Super NT menu from the game, is you have to do this every time you startup your Super NT.
Workaround: You have to disable hotkeys in the Super NT menu, but the option appears hidden in newer firmwares. However it can still be toggled. If you scroll 1 past the "Cancel Key" menu entry in the hotkey menu you will get a warning about shutting of the menu hot key. Hit 'Y' or whatever your confirm key is set to exactly once then back out of the menu to your game. You should be set. The main downside of this, besides not being able to enter the Super NT menu from the game, is you have to do this every time you startup your Super NT.