Playing Nekketsu Games with the Four Score adapter.

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FrenchyToasty
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Playing Nekketsu Games with the Four Score adapter.

Post by FrenchyToasty »

I have an Everdrive N8 so I now have the opportunity to play the marvelous Nekketsu Games on my NES, these games are very fun and most are compatible with the japanese 4 player adapter. Unfortunately the japanese 4 player adapter plugs into the expansion contrary to the Nes Four Score which inputs its signal through the controller ports.

In short I (and most likely others since these games rock) would greatly appreciate if someone able to hack could look into it.

I've read a bit about how both adapter work and I've come to the conclusion that somewhere in the game's code there's something that tells the console what P3 and P4 do. We (excluding me of course since I can't code/hack) must be able to change these values to something that will be compatible with the Four Score adapter.

I've heard on Krikkz's forum that Nekketsu Koushin Kyoku is actually compatible with the Four Score so maybe that's a good a good place to start poking. I've also seen that someone hacked Super DodgeBall (USA) to be 4 player.

here's a bit of info I found on the way these adapters work (found right here on this site!)
tepples
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Re: Playing Nekketsu Games with the Four Score adapter.

Post by tepples »

From nes4play.txt, which you linked:
It seems that there are adapters that supply the information in the second bit of $4016 and $4017, but I don't think any games require these.
But that's exactly how the Famicom expansion controllers work.

The hardware description that most of us work from is on the wiki. See Standard controller and Four Score.
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FrenchyToasty
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Re: Playing Nekketsu Games with the Four Score adapter.

Post by FrenchyToasty »

Cool, I'll get an eye on this even if I can't do it myself, I like to know how these things work. Useful informations!

If you know anyone who'd be willing to check to hack these please refer them here!

These games are really good and to have 4 controllers plugged in and the game running but not being able to play them is sad!
Pokun
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Re: Playing Nekketsu Games with the Four Score adapter.

Post by Pokun »

So in other words Controller I and II reads like normal, and expansion controllers (con 3 and 4) read like normal but from bit 1 of $4016/$4017 instead of bit 0. You'd have to look for $4016.1/$4017.1 reads in the code and change them to read from bit 0 twice I guess?


Also you could get an Enio, two expansion port controllers and a Famicom multitap / expansion port splitter (can be built with NeoGeo extension cords) (alternately get expansion controllers that have built-in multitap/splitter). Or build a NES to Famicom controller adapter (also with NeoGeo extension cords) and use your NES controllers in the Enio.
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FrenchyToasty
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Re: Playing Nekketsu Games with the Four Score adapter.

Post by FrenchyToasty »

I like to use only the official stuff, like the Four Score, and it's convenient that I can only carry this and my everdrive and basically can play on any NES.

Thanks for the heads up though! If I have to resort to this I'll do.
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FrenchyToasty
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Re: Playing Nekketsu Games with the Four Score adapter.

Post by FrenchyToasty »

Anyone knows anyone who could get an eye into this game? Nekketsu Koushin Kyoku

It's one of the japanese 4 player games and it does work with the american four score adapter! (just tested it)

I've also seen that Super Dodgeball was also converted to 4 player (USA rom)

I'm sure someone could hack it! Sadly game hacks are so often only thought for emulators...
grynold
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Re: Playing Nekketsu Games with the Four Score adapter.

Post by grynold »

Micro Mages made me get a Four Score and I have since tried out most 4 player games. Im now getting some Retro Bit Power Sticks (arcade sticks) and upgrading them with Sanwa parts.

The ultimate games to play this way would be the Nekketsu games but they are unfortunately not compatible with the four score. I could probably solder in 2 more controller ports in my Nes.
Think Enio Exp board > DA-15 port > Controller adapter.
I would just solder 2 more controller ports directly to the Nes mother board and skip all adapters since i don't have them.

But I don't want to do these mods to my Nes if hacking the roms is easier cause Its more convenient to hock up all controllers to the four score.

So you People with experience, is this a big hack or a quite simple task?
lidnariq
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Re: Playing Nekketsu Games with the Four Score adapter.

Post by lidnariq »

Since no-one else has answered, and I guess I have some practice with input device conversions ...

I don't think it's hard (although I'd find the opposite direction to be easier). Almost all games have exactly one reading routine somewhere in them—e.g. Wit's starts at $FE29 (file offset 0x1FE39)—and you basically just have to patch out the old reading routine and replace it with a different one. The only hard part, and that only sometimes, is finding enough space to put the new reading routine.
FrankWDoom
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Re: Playing Nekketsu Games with the Four Score adapter.

Post by FrankWDoom »

i did the dodgeball 4p hack (the controller part, i borrowed the menu fix). that patch is available here if you need it

http://retro.angelfire.com/kingmercury/ (use an ad blocker)

there are 2 controller routines in dodgeball, more or less 1 for gameplay and 1 for menus. it's pretty well organized.

the 4p adapter for famicom dodgeball reports players 1+3 and players 2+4 simultaneously. the 4 score reports sequentially. so you need to do 4 controller reads to get all 4 pads, instead of 2. additionally you have to do at least one more loop to check if your'e getting valid data for p3 or just noise on the line. the 4 score routines are longer so you need some empty space in the rom. dodgeball had a chunk in the fixed last bank that made it easy to relocate.

i'm not looking for projects right now but i'll keep this in mind if i get motivated
grynold
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Re: Playing Nekketsu Games with the Four Score adapter.

Post by grynold »

Wow thanks! Didn't know about that hack, thought the only hack for dodgeball was the one on romhacking.net and that didn't work with four score.
I tried looking into Nekketsu Kakutou Densetsu with fceux to see what changed when buttons where pressed but since this is more advanced than replacing one bit with another the controller adapter is the easier way for me.
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FrenchyToasty
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Re: Playing Nekketsu Games with the Four Score adapter.

Post by FrenchyToasty »

Just wanted to get back to this and say thank you for the patch, I'm still amazed that the other nekketsu games haven't been patched, I ended up adding 2 other ports to my NES for P3 and P4 by soldering NES controller connectors directly to the expansion port pins related to both.
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