Genesis / Megadrive pad hack - use DB15 arcade stick on Genesis

I have a Madcatz Fightstick Pro TE modded for DB15 / Neo Geo pinout which I would like to use with a Sega Genesis / Megadrive.

I have disassembled a 3 button Genesis pad, and using a multimeter checked the common gound and the respective signals for the buttons:



My question is is it now enought that I solder to these points and then to a male DB15 connector as per the Neo Geo pin out or is there something else I need to do / mod to make this work?

So basically a neo to Genny adapter. If you're familiar with the process of wiring the neo connector, it should be simple, no explanation needed.

Personally, I'd hack a 6 button controller if I were you.

Just solder it to the neo geo pinout. Ensure the half of the button contact you use for each button isn't the part that's connected to ground and you should be all set.

skate323k137 said:

Just solder it to the neo geo pinout. Ensure the half of the button contact you use for each button isn't the part that's connected to ground and you should be all set.

Click to expand...

I tried a simple test just hooking up the Ground and the signal for the Start button. Works fine if you just touch the two wires together - registers as a Start button press, game pauses and unpauses etc:



It get more puzzling when plugging in the connectors into a perfectly funtioning Neo Geo CD pad - Ground in Pin 1 and Start in Pin 11 as per the Neo Geo pinout - no response:



I have found that only the direction controllers - register as button presses - i.e. if I put the Start signal cable in either of these pins then that particular direction control works works fine as the start button... but all other buttons (Start, Select, ,,,) show no sign of life.
Any ideas where the problem is?

The neo pads need 5v to work. AT ALL. you'll have to pull 5v off the Genny pad to the 5v pin on the DB15.

MtothaJ said:

I have found that only the direction controllers - register as button presses - i.e. if I put the Start signal cable in either of these pins then that particular direction control works works fine as the start button... but all other buttons (Start, Select, ,,,) show no sign of life.
Any ideas where the problem is?

Click to expand...

The NeoCD pad needs +5v for the buttons as it has small ICs that need power to register signals. But the directional pad is only switches and need no power.

Lemony Vengeance said:

The neo pads need 5v to work. AT ALL. you'll have to pull 5v off the Genny pad to the 5v pin on the DB15.

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Thanks for your response, I will try connecting the 5v also for the pads.
The major problem I see though is that I want the Genesis to work with my DB15 wired fightstick - I tried it on the same basis as the Neo pad (ground and Start button pins) and it also did not work. THe fightstick does not have the 5v line wired and it was my understanding that this was not a requirement. Getting a bit confused really - if it turns out that the 5v is a requirement for the fightstick also then what should I wire this to inside of the fightstick?

MtothaJ said:

Thanks for your response, I will try connecting the 5v also for the pads.
The major problem I see though is that I want the Genesis to work with my DB15 wired fightstick - I tried it on the same basis as the Neo pad (ground and Start button pins) and it also did not work. THe fightstick does not have the 5v line wired and it was my understanding that this was not a requirement. Getting a bit confused really - if it turns out that the 5v is a requirement for the fightstick also then what should I wire this to inside of the fightstick?

Click to expand...

The 5v isn't a requirement with what you want to do to the stick, 5v is needed if you want to test using a NeoCD pad buttons. Just use the NeoCD pad directions to test all the buttons instead as it's just a switch and will instantly tell you if the connection is correct.

^this. The fight stick (or the original neo stick) will work without 5v

Guys, I wired a DB15 male connector and soldered the wires directly to the PCB in accordance with the NG pinout. The result is that:

- the Neo Geo CD pad works perfectly
- I am however still having major problems with getting the fightstick to work

Basically, when plugged in the fightstick is totally unresponsive, button presses or joystick movement does not transalte into anything happening in a game:



Then every so often, and in no apparent pattern, some lights on the fightstick would come on and the fightstick would become fully playable:



I have tested the fightstick with my Neo Geo MVS setup and it works flawlessly. Same with the PS3. The +5V line is not connected to anything inside the fightstick (its trimmed and fully isolated).

Any ideas where to troubleshoot next? Really stuck on how to proceed to be honest , any advise would be much appreciated.

Got it!

Through trial and error I managed to solve this
Somehow the problem was in the unconnected DB15 lines - initially I had 10 lines connected to the PCB (4x directions, GND, +5V (not connected to the stick however), A, B, C and Start) leaving 5 lines unconnected. After I connected these 5 lines to +5V on the PCB the fightstick started to work flawlessly. Being a newbie to all of this modding I don't know the rationale . reason why this was needed but it works. Since I need to move the whole thing to a proper project box with connections for 2 joysticks I will still be experimenting with this - perhaps those free 5 lines can be connected to GND instead of +5V?
Just one question - as things stand I have the Neo Geo button connected to +5V. This is fine for the fightstick but is there a risk of damaging the Neo Geo CD pad if I press ?

MtothaJ said:

This is fine for the fightstick but is there a risk of damaging the Neo Geo CD pad if I press ?

Click to expand...

Yes.

Xian Xi said:

Yes.

Click to expand...

Thanks fo the heads up, I will try to see what happens upon:
- disconnecting the line going to - it may well be the case that the other lines being connected to the PCB are sufficient for both the fightstick to work and for there to be no risk of plugging the Neo Geo CD pad and pressing
- seeing what would happen if I connect those remaining 5 lines to GND instead of +5V - maybe it less a voltage issue just more a matter of lines at both ends of the cable being connected to the two devices.

I still have the other pad to do so there will be plenty of room for testing this out in due course.

Completed!

Finally got around to completing this thing:





So basically its 2x DB15 ports in a plastic box wired to the Megadrive controller PCB's. The plastic box seems very strong - absolutely no flexing when connecting disconnecting the DB15 controller, also the top pops off for easy access. I also shortened the controller cables coming out the back and going into the Megadrive. This was the hardest part for me as it was very fiddly to connect the cable back together - the wires inside were very thin, difficult to strip and prone to breaking. That said I made sure that the was a good, soldered connection further insulated with electric tape for each wire and then wrapped the whole thing in duct tape - not exactly pretty but does the job.

As for the button thing and the possiblity of a short circuit which we were discussing - I disconnected Pin 4 which goes to and the whole thing works fine. That said the NG CD pad has Select and I have that pin also wired to +5V. Unfortunately, upon disconnecting that pin from the voltage the whole thing started functioning eratically so I had to reconnect this back to the way it was. I guess should one want to play on pads its just easier / better to buy some original Genesis / Megadrive ones than experiment further with this*

*caveat - providing the're in good condition - the two pads which I used to make this contraption where totally clapped out / rather unresponsive and with dirt etc. everywhere - not a pretty sight.

MtothaJ said:

not exactly pretty but does the job.

Click to expand...

My thoughts exactly ^^ congrats on finishing your project!

Sorry to necro this but I'm trying to make a similar hack to use my TE stick on the genesis.
I've only hooked up what I needed (4 directions, 3 buttons, start, Ground) and the fight stick does not work right at all. If I hold down one of the buttons and then try others, I get some stutter but thats about it.
I wonder like you said if its a TE stick thing but the +5v might be needed. The odd thing is the Neo MVS/CD do not need this +5.

I'll try to add the +5v now and see what happens, Im not sure why the rest of the empty ports on the DB15 would need them to be piggybacked on there.

It most likely needs the +5v since it uses an IC unless it pulls it from a signal line which is easy to check.

I was finally able to get things working. Here is what I did but note this is only to use a madcatz style fightstick that has already been modded with DB15 to work on the NEO.
I wired up all 4 directions, Ground, +5v, ABC Buttons and Start.
For the remaining 5 connections not in use on the DB15, you'll need to hook up 4 of the 5, omitting pin 4(D). I ran into issues with accidentally hitting D and it would freeze up.

Here is a pic I found that helped me, I've edited it to show the solder points I used. Hope this helps someone out as I wasted many hours.

I just did the same thing based on these guides, and have a better image to contribute for anyone in the future wishing to do this:



I only had to connect the points shown in that diagram. My DB15 did have wires at the unused locations, but they aren't soldered to anything.

It's basically set up in a project box that connects between my MC-Cthulhu and Genesis. Works wonderfully!

ballzdeepx said:

Sorry to necro this but I'm trying to make a similar hack to use my TE stick on the genesis.
I've only hooked up what I needed (4 directions, 3 buttons, start, Ground) and the fight stick does not work right at all. If I hold down one of the buttons and then try others, I get some stutter but thats about it.
I wonder like you said if its a TE stick thing but the +5v might be needed. The odd thing is the Neo MVS/CD do not need this +5.

I'll try to add the +5v now and see what happens, Im not sure why the rest of the empty ports on the DB15 would need them to be piggybacked on there.

Click to expand...

I had similar problems to start off with, adding +5V to the TE stick resoved this to a degree, since all in all the stick was functioning well and I could do without connecting the remaining DB15 wires. However still from time to time I had problems with the auto fire module on the PCB when using DB15 - on some systems the lights would just come on at random and start flashing (no big deal, but could be annoying) while for other applications the autofire would turn on after playing for a while or seemingly at random without the possiblity of turning it off (I found that plugging and unplugging the joystick fixed this for a little while but thats hardly a good solution, especially in the heat of gameplay).
Ultimately I decided to bypass the PCB altogether - posted an update to the TE stick mod thread - http://www.neo-geo.com/forums/showt...o-TE-DB15-Neo-Geo-mod-wth-pictures&highlight=

As for the padhack box, at one point I want to add a single pole triple throw switch to change the orientation of the buttons for when I want to plug in a Neo Geo CD pad. At the moment its optimised for the fightstick with the all being in one line. This is fine but when you connect the Neo Geo CD pad you get a layout which sucks:



So I figure the switch would just change around the buttons so that
- on the NG pad corresponds to A on the MD pad
- on the NG pad corresponds to B on the MD pad
- on the NG pad corresponds to C on the MD pad

Or you could use the button instead of as the MD B button and go for a SG Propad style layout:

Mercuttio said:

I just did the same thing based on these guides, and have a better image to contribute for anyone in the future wishing to do this:

I only had to connect the points shown in that diagram. My DB15 did have wires at the unused locations, but they aren't soldered to anything.

It's basically set up in a project box that connects between my MC-Cthulhu and Genesis. Works wonderfully!

Click to expand...

hey so do you think you can help me pinpoint the ground on this one?

right there.

The multiplexer (or whatever the fuck it's called) chip in a Genesis controller is an off-the-shelf part. You can just make your own little adapter with that and a small project PCB.

Lemony Vengeance said:

right there.

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Goddamn well that was fast! Thanks Lem!

Now that i look at it, it seems so obvious. Solder point that spreads out into a green plain. Makes sense.

The multiplexer (or whatever the fuck it's called) chip in a Genesis controller is an off-the-shelf part. You can just make your own little adapter with that and a small project PCB.

Click to expand...

well im not sure what youre talking about but all im trying to do is turn this into a quick genesis stick.

If you have some kind if better way to go about doing this im all ears. definitely open to building a project box

Jibbajaba said:

The multiplexer (or whatever the fuck it's called) chip in a Genesis controller is an off-the-shelf part. You can just make your own little adapter with that and a small project PCB.

Click to expand...

In the 3 button stick, about certainly. Is it also an off the shelf part in the six button one? It has been my suspicion that it's not, though I haven't checked.