> > Which existing gamepads are available that meet these requirements? Which six > button > > gamepad can be used to play "Street Fighter II"? > > I'm not aware of any 6-button console controller that's wire-per-button. You're at 10 > wires just for the buttons and d-pad already then, and > SNES/Genesis/PSX/N64/Gamecube/Dreamcast all have fewer pins than that.
Saturn is multiplexed wire-per-button, which is way simpler than having to handle a protocol. You can do the scanning in hardware easily.