MiSTer FPGA Forum

Hi. Does anyone get multitap working with Famicom games? I have 4 controllers, and wished to try some of the Nekketsu games with my friends. Downtown - Nekketsu Koushinkyoku does work with all 4 players active. While Nekketsu Koukou Dodgeball-bu doesn't. Only players 1 and 2 are moving, while 3 and 4 doesn't respond to any presses.
I guess Famicom has a little bit different multitap implementation than NES one.

Btw, is there a SNAC adapter for Famicom expansion port?

I can't remember my methodology but I'm sure I got 4-player working on Famicom a while back (Bomberman 2 if memory serves). I won't have access to my MiSTer until the week after next but I'll ask around.

Try MisterAddons.

There are three main methods by which games can use more than two controllers on a NES/Famicom:

1. the Hori multitap (aka "Famicom Four Players Adapter") on Famicom*,
2. the Four Score (or Satellite) on NES**, and
3. "simple" expansion port usage on Famicom* (using hardwired controllers on older Famicoms or the NES-style controller ports on the AV Famicom as player 1 and 2).

* Or less common, on NES systems with an adapter or modification to add a Famicom expansion port.
** Or less common, on an AV Famicom; even less common, presumably an older Famicom could be modified with NES-style controller ports instead of the hardwired controllers.

But I only see the one Multitap disabled/enabled option in the MiSTer core. Presumably additional options would be required here, unless I guess there's a desire to trust the NES 2.0 header's default expansion device field to choose which method to use. (Aside, apparently the first two methods can be combined for 8-player support, though I don't know of any games that support anything more than 4 players.)

See the NESDev wiki four player compatibility list. Some games support all three methods, others only one or two of them. Apparently Nekketsu Koushinkyoku supports all three methods but Nekketsu Koukou Dodgeball-bu is only known to support the "simple" method. Interestingly enough Bomberman 2 supports different methods in different ROM regions.

I'm not entirely sure SNAC would help here with the current core? I could be very wrong (don't really know Verilog), but it kind of looks like when the user port is used, it only populates $4016 D0 (and D2 but not from the user port) and $4017 D4, D3, and D0? That is to say, when normal controllers are used with SNAC it looks like they only replace what would be an older Famicom's hardwired controllers. Both Famicom methods above require the use of D1 at both addresses instead of D0. But presumably this could be addressed with an additional option; the current SNAC options are "Off", "Controllers", "Zapper", and "3D Glasses"; maybe an additional "Controllers (expansion)" option could be added that would hook the SNAC controllers up to D1 instead of D0.

Well, I've tried 4 USB/Bluetooth controllers. SNAC question is a separate one, I guess I should create another thread about it.

bry111 wrote: ↑Thu Jul 21, 2022 6:06 am maybe an additional "Controllers (expansion)" option could be added that would hook the SNAC controllers up to D1 instead of D0.

Famicom expansion port is one of the coolest things that happened to Famicom platform - there are tons of weird hardware (how about inflatable motorcycle?) which can be attached to it. So it would be really cool to be able to connect them to MiSTer too.

nymous wrote: ↑Fri Jul 22, 2022 10:16 am

bry111 wrote: ↑Thu Jul 21, 2022 6:06 am

maybe an additional "Controllers (expansion)" option could be added that would hook the SNAC controllers up to D1 instead of D0.

Famicom expansion port is one of the coolest things that happened to Famicom platform - there are tons of weird hardware (how about inflatable motorcycle?) which can be attached to it. So it would be really cool to be able to connect them to MiSTer too.

Totaly agree, i have a lot of Famicom accessories and i would like to use them on MiSTer with a DB15 SNAC adapter.
This is something we have hope to see in a near futur ?

[quote="Allan Theo" post_id=67394 time=1673454160
Totaly agree, i have a lot of Famicom accessories and i would like to use them on MiSTer with a DB15 SNAC adapter.
This is something we have hope to see in a near futur ?
[/quote]

I've been meaning to order this and try, but don't know if it will work. Good luck!

https://ultimatemister.com/product/mist ... hdmi-mini/