Hacking a NES Controller to jamma test station.

Thomas

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I have NES pad here I want to hack for my jamma test station. I have a few diagrams I found on the net but my search has turned up empty for direct instructions on the best way to do this. So I figure with some help we can work out the best way here on the forum so everyone can do this.

So to kick it off I have these two diagrams. They do seem to be a little different from each other.
 

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Now here is a picture inside the NES controller...

Since I am wiring this to jamma would the first step be cutting the 4201b chip out? Then using the legs from that chip to attach my wires?
 

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Any reason you need to use the NES controller? I made mine w/ Sega controllers, which really doesn't require any work. The connector is a standard DB9, and the buttons are 1 wire per pin, rather than having to cut out the chip and run your own wires. You have to use the Sega Master System pinout, but Genesis controllers are easier to find and work as an 8-way joystick plus two buttons.

http://pinouts.ru/Game/sega_ms_joy_pinout.shtml

DogP
 
Any reason you need to use the NES controller? I made mine w/ Sega controllers, which really doesn't require any work. The connector is a standard DB9, and the buttons are 1 wire per pin, rather than having to cut out the chip and run your own wires. You have to use the Sega Master System pinout, but Genesis controllers are easier to find and work as an 8-way joystick plus two buttons.

http://pinouts.ru/Game/sega_ms_joy_pinout.shtml

DogP

This is exactly what I'm doing with mine. Sega pinouts are nice and easy. Keep it on the 3 button controller, not the 6 button. You only need 3 anyway for JAMMA.
 
Any reason you need to use the NES controller? I made mine w/ Sega controllers, which really doesn't require any work. The connector is a standard DB9, and the buttons are 1 wire per pin, rather than having to cut out the chip and run your own wires. You have to use the Sega Master System pinout, but Genesis controllers are easier to find and work as an 8-way joystick plus two buttons.

http://pinouts.ru/Game/sega_ms_joy_pinout.shtml

DogP

+1 for great info, i'm going to use this on my test station.
 
This is exactly what I'm doing with mine. Sega pinouts are nice and easy. Keep it on the 3 button controller, not the 6 button. You only need 3 anyway for JAMMA.
Yeah, definitely stay with the 3 button controller, because of backward compatibility that the 6 button may not have... but using this pinout you actually only get two buttons. To get the third and start button, you need to toggle the select pin and demux/register that pin.

It's not worth it IMO, though if you want to modify the controller, you could wire +5 and Select to the third and start buttons. I personally connected switches for coin and start directly on my test station and use bone stock Genesis controllers

DogP
 
Any reason you need to use the NES controller? I made mine w/ Sega controllers, which really doesn't require any work. The connector is a standard DB9, and the buttons are 1 wire per pin, rather than having to cut out the chip and run your own wires. You have to use the Sega Master System pinout, but Genesis controllers are easier to find and work as an 8-way joystick plus two buttons.

http://pinouts.ru/Game/sega_ms_joy_pinout.shtml

DogP

Hey man...

I was using the NES controller because it was what I had here in hand atm. I will keep an eye out for some sega controllers but I am stuck with the NES for now.

What I would like to have up at the controller end is test and service as well. That's the way my test rig is set up so the NES controller has those two extra buttons.

Again I am not playing games with this thing and I know its only 4 way but its a test rig nothing more.

I think it would be cool to have all the hacks for each game controller here on the forums. Maybe we could all work on a little section just for this purpose.

Thanks for the link d/p!

http://pinouts.ru/Game/snescontroller_pinout.shtml

Based on what I have read I will need to clip the chip on the NES. No biggie cause I have already clipped the 7 pin plug off the other end anyway.

I have a shit load of db 9, 15 & 25's so that wont be a problem. I might just beef the wires up a bit and run them like my test rig to 084 pins and the housing.
 
Whelp the NES controller is out lol. I destroyed that thing trying to clip the chip out. I bent/mangled one pin pretty bad so I fired up my de-solder station and the nozzle was to big for those small arse pins. I pulled up a trace on the other side err. I got mad and thru it in the trash. One less NES controller in the word this morning!

Oh well, so I took the advise from dogp and pulled the trigger on two classic three button genesis controllers on flea bay. lmao

</close>
 
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Yeah, definitely stay with the 3 button controller, because of backward compatibility that the 6 button may not have... but using this pinout you actually only get two buttons. To get the third and start button, you need to toggle the select pin and demux/register that pin.

It's not worth it IMO, though if you want to modify the controller, you could wire +5 and Select to the third and start buttons. I personally connected switches for coin and start directly on my test station and use bone stock Genesis controllers

I hadn't looked close enough at the pinouts prior to your post. I just assumed that 4 directions, 4 buttons and ground = 9 pins. Didn't realize they wasted pins for +5v and then needed a select line for another bank of switches. I mistakenly assumed this was only done on the 6 buttons. I think I had read somewhere that the Genesis 3 button controllers were mostly passive (similar in pinout and operation to the Atari 2600).

2 Buttons should be fine for me, I have a break-out box I'm building into my JAMMA test rig that will house the 9-pin port for the Genesis controller, and the plan was to use that for additional buttons that the controller couldn't do... JAMMA Test/Service switches, coins, etc. I'll likely still rewire the innards of the Genesis controller to get the additional button or two. It won't be stock, but I did buy one specifically for this purpose from a flea market so it won't bother me to have it modified. I'll just have to keep it separate from all of my other Genesis controllers. :)
 
An NES controller is a very simple device - just a shift register to encode all the buttons. The data is serially sent to the console. To modify it, you need to remove the chip, cut out the printed resistor tracks, and wire the individual buttons to a new cable (the existing NES cable doesn't have enough wires). I did something like that many years ago to use an NES pad on the Atari 2600.

That said, for a test station, I use a Sega Genesis controller, the three button kind. I modified it slightly, to bring out all three buttons on their own wires (they're multiplexed with a 74HC157, to allow for more buttons), I just desoldered the chip and added some jumper wires inside.

I don't have any step by step directions or anything for you - I just followed the tracks on the board. On my test station, the test/service/slam and coin/start buttons are on the test station itself, and the controller port is wired to the directions and the three standard Jamma buttons.

-Ian
 
I did make a supergun in a NES case (the NES was very dead to start with) and did make a little circuit to run off the NES joypad ports so I could plug in NES pads in. The circuit is not that difficult to make and saved me having to hack up pads, and means I can plug in any old NES controller into it. Most of the games I wanted to play only have two buttons anyway, although made Select the Start button, Start button 3 and A and B buttons 2 and 1. :)
 
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If you want to use an NES pad, why not ignore the IC and hack the pad to solderpoints and run them to your JAMMA loom? You don't need to even have the IC there, you should hurry and take your pad out of the trash. Just wire the ground area on the pad to ground on the jamma and the directions and buttons to your harness.
 
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