Universal Joysticks

Universal Joysticks (Part 2)

Welcome to the Universe…

Well now the sticks have been built, and work on my Neo Geo. However one of my main goals with these sticks was to make them work on any game platform I choose, so it was time to build some adapters. There a lot of different ways to do this, however you'll see the way I chose was the easiest and costs the least amount of money.

The basis for an adapter starts with a working controller for the target system, be it Playstation, a USB gamepad, or whatever else you want. What you will end up doing is ripping the insides of that controller out and soldering onto the metallic leads of the circuit board. Let me explain.

What we have on the Neo Geo pinout is an output of each button in digital form, whether it's being pressed or not. They don't do this on new consoles anymore; they have an encoded signal onto a small amount of wires. This is why there are only like 6 wires at the end of a PSX controller, and it's also why there are little chips on the circuit board of these controllers. However, even if these controllers encode what button is being pushed, they still have a level where the data collected by a chip is whether certain buttons are being pressed or not. Much like how the Neo pinout provides the controller information to the system.

So if you connect the output of your buttons from the Neo controller to the inputs of the encoder chip on the circuit board, it will encode that button as if it were the actual button on that pad.

Now that I'm done with all the theoretical talk, lets get practical. You have to hack a game pad for each converter you want to have. And let me tell you, hacking a controller and soldering up the connections is a really long and tedious process. So we have to look for an easier solution. What I decided was to actually build an adapter for Playstation and then buy PSX to whatever adapters. So I have PSX output going to a PSX to Dreamcast adapter, or a PSX to USB adapter. Hell if I wanted to I could buy a PSX to XBox adapter. Let me explain why I choose to build a PSX adapter. Due to the fact that Sony has won two console wars (they practically have the current war in their pocket), it has made the PSX controller interface a standard of sorts. So it's extremely easy to obtain PSX adapters.

This may sound like cheating, but it really saves you a lot of money. Because if you add up the amount of money it costs for a 3rd party controller, the wires, solder, and DB15 connectors, it adds up to be more than the $15 that these converters will cost you.

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However, lets get down to the heart of this, the PSX adapter.

The first thing you have to do is buy a cheap old, all digital PSX controller. But make sure it's not the official Sony brand!!!! The cheaper off-brand controllers will use metal for the button contacts on the circuit board. The Sony brand uses zinc contacts, which you can not solder to. And if you try to solder to the tiny copper test spots that are on the Sony controller, you'll find that they will literally tear off of the board with a small amount of force. Also, I've found some of the "new" cheap Digital only PSX controllers they're selling today for like $5 at Best Buy or places like that are not PS2 compatible, so you'd best watch out for those.

Now if you've gone through and made the sticks, it's safe to assume you have a good understanding of how they work.

Basically you want to map each button from your joystick to a corresponding button on the PSX pad. Below you can see a chart and picture of how I mapped the buttons, I feel that this configuration makes the most sense and gives you the best flexibility.

Pin #	PSX
1	Common
2	L1
3	Select
4	R2
5	X Button
6	Right
7	Down
8	Square Button
9	Triangle Button
10	R1
11	Start
12	Circle
13	L2
14	Left
15	Up

What you'll need for this is some more 15-wire cable (a single cable that has 15 separate little wires inside of it). Some sort of closable case to put the hacked circuitry into (and keep it secure), electrical tape, solder, standard electrical wire, and two Male DB15 connectors.

I ended up using an old plastic VCR cassette case for my container. It actually works very well since I can easily open and close it, and it can keep the cables secure. Remember you're converting two pads for this, so make sure your container is big enough to hold this.

The final PSX Converter

The first step is to go through the tedious process of soldering the connections from the DB15 connector to the 15-wire cable.

Next you'll want to create the holes needed to feed your cable through.

Drill two holes in the "center" of the side of the case. These are for the 15-Wire cable to feed into the container.
1. Check the width of your cable against your drill bit size. You want this to have a nice snug fit inside the case.
Drill two smaller holes near the opening of your container. This is for the PSX cables to exit the container. You'll see how my holes are almost right where the case closes. I left a tiny bit of room and used a pair of scissor to cut a small line from the top of the plastic to my newly created hole. So to put in the PSX cable I just had to bend the plastic a little bit to put it in.
1. a. Again, check the width of your cable against your drill bit size. You want this to have a nice snug fit inside the case.

After that, you'll want to feed your 15-wire cable through their entry holes. Then begins the next tedious process of soldering leads of wire from each of the small 15 wires to the spot on the PSX controller. Use an Ohm-meter to test for continuity, making sure that you are wiring the correct button from the sticks to the right button on the PSX pad. Also, be sure to cover the connections you make from the leads to the 15-Wire cable with electrical tape. This way you can be sure you'll never short out a connection.

The only thing that may be a little tricky is finding the "Common" voltage for your pad. Most, if not all, PSX pads use Ground (+0V) for their common. An easy way to find a place to solder to for this is to look at the traces of wire on the board. It shouldn't be hard to find a large one that is connected to one side of every button. This should be the ground plane. You can verify this by using an Ohm-meter to check the continuity between the spot on this part of the circuit you'll want to solder to and the Black wire that's coming from the controller wire. They should match up, confirming it's the ground line.

Do try and be as neat as possible. This way it will be easy to fit the finished circuit into your case.

Once you're done you'll want to fit the PSX controller cable into the other two holes you made in your case. Then it's time to close it up the container and test it out. Don't forget to pray first.

The innards of the PSX Converter. Hey I didn't say it was pretty!

If it all worked out, then congratulations, you've built the converter. If not, then try to troubleshoot where you went wrong. Test each button on the joystick individually, on both player ports. Make sure it's doing what it's supposed to be. If there is a problem then there are 3 places a connection can be bad (assuming the joysticks themselves are assembled correctly).

They are:

On the PSX controller board. You may have short-circuited a button with too much solder. Or some other small mistake.
Check the soldering from the leads to the 15-Wire cable. Make sure they all have a good connection.
Make sure the 15-Wire cable is properly soldered to the DB15 connector.

If you don't get any button responses at all, then you'll want to verify that you have Pin 1 on the connector wired to the ground plane on the PSX controller board. And also make sure that you have Pin 1 on the Male DB15 connector going to Pin 1 on the Female DB15 connector that leads to your joysticks. A good way to check that out is to plug the controller into the converter (do not plug the converter into the PSX), and use the Ohm-meter to check for continuity between the ground plane on the controller and one of the "common" inputs on one of the buttons inside the Universal Joystick. Hopefully, you'll be able to find your mistake and find out that you didn't fry the controller circuit board.

Special Case: Dreamcast

Now that we have our joysticks with PSX output, the plan was to buy converters for each new system we wanted. This works out well with the PC, converting all the buttons as if we had a 10 button USB controller. The Dreamcast (DC) converter however gives us a problem. The PSX has 4 shoulder buttons: L1, L2, R1, R2. The DC only has two. So the converter logically converts L1 or L2 being pressed as pushing the Left Trigger on DC. Giving us this controller layout:

This however gives us a problem if we want to play Capcom fighters on the DC. Since the Capcom button layout has two buttons doing the same thing. Luckily there is an easy fix for this. What I ended up doing was getting a Single Pole- Double Throw (SPDT) switch, and hooking it up like this:

What this shows is that you hook the output of Button D to the center point of the SPDT switch. Then what you do is run a wire from Pin 4 on the DB15 connector (basically a lead from the correct wire on the 15-Wire cable coming from the DB15 connector) to one of the points on the side of the switch. Now comes the tricky part. Solder two leads from Button A, one going to Pin 13 as it normally would, and then one wire going to the other point on the Switch.

I mounted the switch inside of the sticks because I couldn't find one big enough to actually mount on the outside. This sounds like more of a problem than it really is, because you rarely have to change the configuration (unless you switch systems constantly), and even when you have to change the switch it's not hard to just swing open the bottom of the sticks, flip the switch, and latch it up again. It's a 5 second job, literally.

Conclusion

Well there you have it, two Universal Joysticks. I'm not going to lie to you; it's not an easy job. Putting it all together must have taken about a 3-day weekend's worth of work (mostly for the tedious parts of soldering up connectors and the like). But I can tell you it's worth all the effort you have to put into it. You can now play perfectly ported arcade games like Capcom vs. SNK 2, Marvel vs. Capcom 2, Street Fighter 3: Thrid Strike, any game that runs under an Emulator on PC, as well as any Neo-Geo game (be it on MVS, AES, or CD). I can't be more happy with how it all turned out and I highly reccomend that people take the time to build a similar setup. Because even if it's a lot of work, if I can do it, you can do it!