MiSterAddons.com has just released a $13 controller adapter that lets you use SNES controllers on original NES hardware. The NES A button is mapped to SNES B and the NES’ B button is mapped to Y – Basically, this is the exact way you’d want the buttons oriented. Also, since this is a passive device, it’s 100% ZERO LAG; No active circuitry is required, as it’s just wired to pass the corresponding buttons. More info and a demo can be found below the link:
SNES to NES Adapter: https://misteraddons.com/products/original-hardware-controller-adapters?variant=40064228294789
As a note, I tried to link to the exact adapter, however MiSTerAddons lists multiple controller adapters for different consoles on the same page – It’s really easy to order the wrong one! Please double check before ordering.
This adapter should be compatible with any standard SNES controller, however other peripherals will most likely not work; I tested using the Konami Justifier to play Duck Hunt and it didn’t register at all. The Super Scope works much different than the Zapper, so that counts out all light guns. And I’m sure stuff like the SNES Mouse won’t worth either.
Any standard controller / control stick should work perfectly though, however I don’t own any wireless SNES controllers, so I wasn’t able to test those at all. I did use it during a recent livestream and it performed perfectly with an original SFC/SNES wired controller!
And lastly, if you’re wondering how it’s possible to just wire an adapter, I strongly recommend watching Chris from Displaced Gamers video about how the NES controller works! You’ll get a good idea of what the shift register does and how it differs from the SNES version!