4-Player NES? Is it possible?

Hello, is there any way to play 4 player games on the Nintendo Entertainment System using RetroArch?

Below is a link to a list of games that use the NES multitap:

For those who may want to know, I can confirm that the 4 player multitap works for the following cores/systems: genesis_plus_gx_libretro.dll (Sega Genesis) snes9x_libretro.dll (Super Nintendo) mednafen_psx_libretro.dll (PlayStation)

I would also like to know if this is possible, Binary.

Also, just as a quick aside, do you have any issues with 4 players on the Genesis? I ask, because I got multitap working on all the systems you mentioned, but on the Sega Genesis getting the multitap working seems to have made 2 player games not function properly (as in, any game that supports 2 players max no longer detects the second player). If I turn the multitap on player 2 off, then 2 player games go back to functioning properly. Have you encountered this issue? I’d love to have a way to leave multitap on without making 2 player games unplayable.

Anyway, back to the topic. If anyone knows how to get multitap working on the NES (or if it’s even possible) I’d love to hear from you. Frankly, if anyone has gotten multitap working on ANY systems other than the ones Binary mentioned, please let us know how you did it.

I’d really love to get multitap working on any and all systems/cores that support it.

Regarding the Genesis behaviour with the multi-tap, this is how the original behaved, most games weren’t programmed to understand the multi-tap input and so wouldn’t work correctly. You also find this on some SNES and PSX games as well… if they weren’t written specifically for the 4 player adapters, its kind of a toss up as to whether they will work correctly with one “plugged in”. Multi-tap support also works for Yabause (or it did months ago when I last tested it) up to 8 players.

It probably requires NstDatabase.xml in your system/bios directory to work in nestopia, similar to the zapper. I asked tehcloud about it but he hasn’t responded yet.

Thanks for taking the time to respond, guys!

OmniBlade, so then, is the only real solution on those systems to configure the inputs on a per game basis? Hmmm, tediousness aside, how would one go about doing that? EDIT I see that hunterk and Radius discussed per game configs using the override system here: http://libretro.com/forums/showthread.php?t=3546

hunterk, let us know if you hear anything back from tehcloud. I’ll keep trying stuff and searching for info, but I’m not coming up with much so far. : /

Just heard back and nestopia indeed handles 4-player detection through the database.

Awesome! That’s great news. Is there an explanation somewhere of how to set it up using the database?