Challenge - how to make your own D-pad -

A D-pad with only 4 directions is in fact able to play games on the GP2x as 8 way. The doubters were adamant that Vektar wouldn't work - wrong - works perfectly. First game I played on it I got 78,000 points with my D-pad - is this good for a first play? You don't need a special chip, etc.

People are seemingly having lots of issues with the stock stick, especially as moving the stick to the left direction seems to get more problematic as the stick gets more and more use.

I thought, rather than keeping my project purely to myself (after I got seriously annoyed by a lot of post replies from people who could only demonstrate their loutishness and ability to be destructive rather than be constructive ), I would set you all a challenge - make your own, and use this topic to post your updates and pics (I won't post my pics yet as I want to see how you get on).

To all you doubters, I can confirm that my D-pad project has progressed nicely, the design has changed dramatically, the unit is quite robust now, and it plays all game beautifully I have thrown at it, including diagonals (I haven't tested all games of course, just the couple of hundred of games (inc homebrew) I wanted to play).

Naturally, you will have to open your GP2x to do any modifications to it. If you were intending to modify your unit with another product then you will have the confidence to do this anyway. Naturally, you run the risk of invalidating your guarantee by opening your case and playing with the insides, you are responsible for your own actions and any damage you might cause by any means, your choice and risk, usual covenants apply, I am not liable or responsible in any way for anything you do or attempt to do, etc. As you know, this all also applies to firmware updates! I am only reporting on what worked for me - make a judgement and take your own educated risks.

I can confirm that the connectors at the back of the stock joystick appear to do everything you need - connections for the push button and the 8 directions. You do not need any special chips or electronics for this mod (unless you want to waste your money of course). You also don't have to do any drilling of your case or even remove the stock stick (see below).

The beauty of this mod is that if you don't like the result, you won't have damaged your GP2x case (unless you are careless or han-handed), nor removed/cut out the joystick; and by removing the solder from the joints from the wires for this mod, your GP2x is back where it started from.


Connection of the wires:

Looking at the joystick connections (top right on the GP2x motherboard, when you remove the 4 screws and open the case)



C & I seem to do the same thing and only one is required, so I use "I" (try using "C" if you prefer).

A+I = up
D+I = left
G+I = down
J+I = right
F+L = centre push

Considerations for your build:

i) Use the thinnest (insulated) wires you can get - ones from an old (and no longer required) joystick/gamepad/scart cable ideal. They need to be thin, you need to get 7 wires though the front of the GP2x in the joystick hole. Use quality solder - 60/40% standard electrical solder is fine.

ii) If you use an existing D-pad from a games controller (eg Nintendo one, or whatever), you have the problem of drilling a hole in the GP2x case and ruining it, and also supporting a flat circuit board in the right position, reliably (and removing the stock joystick unit completely). Not a good idea in practice. Best to make an external D-pad - you need to make one yourself (which is what I did). This means making a solid base, and a top which completes the contacts.

iii) An external D-pad assembly has to fit over the place the existing joystick is based (wires connecting from the D-pad, round to the back of the motherboard by the left shoulder button (you can see the recess in the picture above), soldered to the corresponding contacts as shown above). The external D-pad needs to be secure on the Gp2x so it doesn't move, yet able to be removed if you want to (so don't use glue!).

iv) You need to mount a basic switch for the centre push button - you must have a centre push, as most emulators and games on the GP2x use it to exit to menu or during the game itself. This is ideally situated next to, but not on the D-pad, as otherwise it makes assembly more difficult, and gets in the way anyway.

v) A switch is only two contacts separated, when pressed together make a contact. This can be done my many methods, including using metal and foam pads, rubber, whatever - depends how flat you want them. Flatter final product, the better. You need to make 5 switches in total (directions and push). The contacts separating the D-pad can be made in a large variety of ways.

vi) Don't laugh, or go "WTF"; but you can make a reliable D-pad with: sticky foam pads, mounting board, self-adhesive floor tiles, tin foil, staples, adhesive labels, foam, tissue paper and glue. Household items. Might sound rubbish, but with this you can make a cheap, sturdy and reliable unit, and a basic circuit board (if you want to make a flat and good job of it), which you will need to do. It looks quite good too as a final product, and is easy to modify if you need to for any further improvements. Don't laugh - experiment - my unit works perfectly, and is reliable, and quite good looking. You are only restricted my your ability.

vii) Test your completed product's circuits all work fine by connecting a battery to a light, touch the 2 corresponding wires of your D-pad to these wires (ie one of the wires from the battery/light to the wire you intend to solder to "A" and the other one to "I" to complete the circuit - press the D-pad in the "up" direction, and if the light works, test the other contacts - when all work, think about attaching it to the GP2x. If you haven't made a unit which responds to up/down/left/right/push, don't install it in the GP2x - you can test the unit easily by this proceedure.

viii) D-pad needs to be elevated above the stock joystick as you don't want the joystick to move at all - the D-pad needs to be above the stick, the only relevance the old joystick has is that you are using its connections at its rear.

ix) Make the unit to be strong, but also as flat as possible. You can adjust how responsive you like the D-pad to be by the materials you use. Mine is very responsive - as I like it.

Challenge:

Make your unit. Should only cost you pennies to make it (but a fair bit of time). Post pics and comments as well as your WIP.

I will be interested to see how many of you are creative enough to do this, and what your final unit looks like. When others have posted their pics, I will post mine. Could be fun, and productive.

It is a shame that people flamed me so much abuse on my previous D-pad topic, there are many hostile and childish people on this Forum.

I figured:
* show you how to make your own D-pad unit in a way which doesn't need major work on the GP2x (and backward compatible)
* let you experiment with making one which looks nice and is reliable
* post your pics and get praise and comments
* see who can make the best unit
* make a good project for people
* provide a way to test the D-pad before even opening your GP2x case - nothing ventured, nothing gained
* gives me a chance to give a positive contribution to the community
* either people will make their own D-pad (great), or if I decided to sell mine (probably won't, will see how it goes) - 1) people won't steal my work (as I have given away the principles of it here anyway), 2) people will hopefully realise how great this system works and will stop making comments to the contrary. As the saying goes, "proof is in the pudding".
* I have a good working unit - will be interested to hear how you get on

thanks bacteria.
I can't understand nothing, I hope somebody will try.
Pad is the only thing I hate of this wonderfull console.

Thanks for your inspiring post!

The D-Pad is my main gripe about the GP2x, it really spoils the experience.
You've obviously spent alot of time researching this. I myself am not too confident about soldering, but if I have time (and bravery) I'll give it a shot and post a WIP

Ideally I would want to replicate the Dreamcast D-Pad - my personal favourite.

Thanks for your positive comments. Yes, I have spent a lot of time researching this and making prototypes. I got the wiring details from finding a .pdf of the joystick itself, which showed what connected to what.

The soldering is easy - normally, soldering requires delicate and precise work - fortunately, the pins stick out of the motherboard by about 3mm, so they are very easy to solder too. My soldering skills are not good either, and I have had to solder and desolder and resolder many times (with each prototype I tried). There is no need to do any soldering for the D-pad itself - use glue and staples and the sticky-backed materials!

Good luck with the project. You can replicate whatever you want that works for you.

Addendum - if anyone needs more information on the build, please ask and I will do what I can to answer them. I have kept further details away at this stage, to give people the chance to come up with their own solutions to the problem - they might come up with a fantastic solution that way, rather than just being steered into my solution method. Evolution!

Good luck!

Wow, thanks for the diagram I would definately attempt to make this since I'm an experienced solderer. But, I would rather not drill a hole to put in my D-pad, and nor would I be good at making a D-pad myself. My question to you is if you can possibly solder the following with ribbon cable together in your diagram:

A+I = up
D+I = left
G+I = down
J+I = right
F+L = centre push

(for instance one end of the ribbon cable would attatch to letter A while the other attatches to letter I)

If I'm correct, if you wanted to use the original stock stick you could, but it would just work like a D-pad. Am I correct with this bacteria? Because I'm pretty tempted to do this

Im sorry if this has been covered, but i couldnt find it:

Are there any specific games that do not work without independant diagonals?
Also, what kind of response do you get in the gp2x test screen? does it register a diagonal, or just the X and Y?

(feel free to point me in the direction of a thread if this has already been covered, which im sure it has).

The test screen just tests switches nothing more, nothing less. So with this mod you will only get an x,y reading as those are the only switches making a connection. It is up to the application to interpret an X+Y contact as a diagonal. Old systems like NES etc would only show X,Y in a switch test program as they all only had X,Y connections as well. It all comes down to how the app is coded. Many will work, some will not.

You don't need to drill a hole in a D-pad - you are making one from scratch, remember! You can't use a commercial D-pad as they are pcb and hard to mount. I used a ring binder hold-punch to cut holes in the card (to stop the stock joystick from coming into contact with the D-pad), and a drill to bore a hole into a piece of floor tile (hole cut to go around the raised circle where the joystick surround it (this holds the unit firmly to the Gp2x and allows removal if required...). Keep it simple!

The wires have to be separate wires, as otherwise you can't feed 7 wires through where the old joystick hole is. A ribbon cable might work, but separate the wires first (and colour code them so you know what goes with what!)

There is a lot of confusion about the joystick/D-pad business . The connections to the back of the joystick itself allows all movements - the 4 directions, the diagonals (which we don't need as the 4 way makes diagonals), centre push. We don't want to use the joystick itself, only its connections (bypassing moving the stick at all). The point is to make a D-pad raised above the old joystick, so you don't accidently catch it, (ie the joystick stick DOES NOT MOVE), when you move the D-pad, it triggers the connections on the back of the joystick fooling it into thinking that you did use the joystick (which you aren't). The point of this is that you can have very accurate movements from your D-pad, ie left is left, etc.

Crude diagram



A - D-pad
B - gap to stop any movement from joystick while you use the D-pad!
C - joystick stick (sticking out of the GP2x a bit) - illustration
D - that lousy stock joystick!
E - the connecting pins for soldering (pertrude from the back of the motherboard)
F - motherboard inside Gp2x

My unit is designed with (about) 85 degrees tolerance with each of the up/down/left/right movements and something like about 20 degrees (in practice, not mathematically) for diagonals. Make yours as you want to. Works great.

Make a unit and test it with an old battery and a light, as illustrated in my post. If you can't make a good unit, you haven't had to open your GP2x, all you have lost is time. Nothing to lose this way!!

Haven't played any games that don't work on this yet. Probably the only possible game is Whacky as that is looking for a specific diagonal key as opposed to up+left=diagonal. I believe the author said (he) would modify their program to allow this. Everything else you throw at it should work, including Vektar, DrMD, MAME, etc, etc.

If it is so really important to have a completely dedicated diagonal (which it isn't) you can use pins B, E, H, K on my post, which are for diagonals. I repeat however, you only need 4 way to behave as 8 way.

Make your own D-pad unit. Any doubts you have about this working (with diagonals in games) will vanish.

I wouldn't mind some more details on how you did this. Obviously it's not too hard to make four functioning switches out of a bit of foil, sponge, glue, etc, but I doubt that I'd be able to make one that was sturdy enough to actually play with.

Have you got any photos of the pad you assembled?

I'm sure that's true, but I still don't really like the idea of leaving 4 unused connections in my device. It's like buying a porche, noticing that it can do 80 mph in 3rd gear and disabling gears 4-6 just to get a more comfortable gear stick. 99% of the time you don't need the extra gears, but why get rid of them when it's so easy to keep them?

I guess I'm a perfectionist.

DaveC - Experiment, make one. You will realise "Many will work, some will not" is actually "Almost everything works, very little if any don't". Theorising is fine, this is a practical solution to everyone's problem!

People can make their own D-pad, with a little experimentation and a few hours to kill, for virtually no cost. The only people I expect to now put post replies saying "it can't work because of diagonals", etc are the people who can't make one themselves and would rather slate an idea (I have no time for these individuals). Make one and try it out.

If they can't make one, no issues (I can assist with advice); if they can't make one which works, they won't have opened the Gp2x, no issues; if they make a working model and install it, they will love what they see and the unit will look as good as their imaginations and skill allow. The alternative is to stay with a stock joystick (even with the best cap design available) with a mind of its own, frequently uncontrollable, and becomes stiff and unresponsive with use.

I am expecting some people to make good working units. Many people may not be able to (or have the time to). I will monitor this thread closely to see how people get on, and will help them with advice on making a D-pad work (for free). I might offer to sell my units to those people who can't make their own (just like you did DaveC !), but would earge people to experiment to make their own, and report back with their findings.

[quote=FluffyPanda,Apr 2 2006, 08:16 AM]
[/quote]

I wouldn't mind some more details on how you did this. Obviously it's not too hard to make four functioning switches out of a bit of foil, sponge, glue, etc, but I doubt that I'd be able to make one that was sturdy enough to actually play with.

Have you got any photos of the pad you assembled?

[/quote]

Yes, you can make a sturdy one. Mounting board is very sturdy (you only need a 20mm circle cut out for the D-pad top. By the time you make the unit, and hide the circuitry/wires, you may have 2 layers of it anyway. Mounting board and floor tiles have a small amount of "give", but for a unit this small, you will find the materials to be rigid, tough and easily cut by scissors.

Yes, I have pics, but I want other people to experiment and evolve this idea, rather than having lots of "clones". Someone may have a better method than I came up with after all.

No FluffyPanda, the analagy is actually using a sledgehammer to crack a nut rather than using a nutcracker . If your car is falling off a cliff, it doesn't matter what gear you use, the result will be the same . You can make your D-pad with all wires connected if you want to, but will make the build harder; and anyway, you don't need to - 4 way=8 way in practice, so your games behave the same way anyway! (experiment!).

Go on, make one!!

I prefer to think of it as a better (though compatible!) nutcracker. But I take your point.

Just out of interest, at this point in time, there have been 350 reads of this topic, it would be great to hear from you guys as to who is going to have a go at making their own D-pad. Do you need any more clues as to how to make one??

If people share their findings and WIP, we could really get a good topic of discussion going here, with ideas going back and forth.

Well, I should have a busted NES-pad somewhere... Definately gonna give it a go.

Now it is so simple I am going to hook up an adaptor plug and have that available to plug in my Commodore Vic20 and Atari 2600 Joysticks for authentic crap control and blisters. (remember those)

I was waiting for USB to add pads but as I want to play it mostly on TV a small adaptor out will do just as well as the TV out is so awkward to use.

Might add an old D pad as well - we will see.

Cheers.

I too had a Atari 2600 around 1980 or so. (I am nearly 40 now - getting old). Yes, after playing for a while, you did get blisters.

Um, this will be unweldy - the joystick you refer to has more surface area than the GP2x! Sure, it would work (you could wire any controller to the GP2x and use it, as long as you know what wire works what direction on your external unit), but, (ahem) how about making something to sit nicely on the GP2x so the unit stays portable? Go on, make a D-pad - you know you want to!!

Oh ok, now I understand. So you basically soldered the corresponding wires from the joystick to a switch (in your case you used tinfoil right?) to recognize the movements through the d-pad to trick the joystick.

Now did you place these switches in between the gap that stops the movement from the joystick? (lettter B in your diagram)

I was thinking that one could use tact switches instead of tinfoil
Here is a pic of what they look like:
You can buy real small ones, I have a couple 4mm tact switches lying around.

Someone mentioned in another thread, the d-pad on Gamecube controllers is pretty tiny. I may pick up a cheap used one.

Absolutely right Minkster!


The wires from the D-pad ( A ) go through the hole ( B ) next to the stick ( C ); the wires then pass through the gap in the motherboard ( F ) by the left shoulder button, and then attach to the pins on the motherboard (rear joystick pins). Luckily, there is plenty of space by the left shoulder button for wires to pass alongside.




Sounds interesting. I used tinfoil because it is so flat, gives good control and contact. Using thin foam stickers (like "sticky fixers" from Sellotape for example) provides a switch as the foam acts as a springy material - when pressed, it compresses and provides the circuit. I used this principle for the Push button, and a central foam pad, cut to size, to pivot the D-pad itself. You need to keep the D-pad final product as flat as possible, otherwise it gets less comfortable to use.

Your tact switches look an interesting alternative, and could be worth playing with. The only issue is whether the final result allows a small amount of pressing to complete the circuit (as with tinfoil and foam, which you can modify to requirements) or if it needs too much pressing to activate. That you will only know when you make a prototype. There are many ways to make a switch after all, yours is nice in principle as it is pre-made; mine is fiddly, but can be made as soft to touch as required.

Interesting idea, I will look forward to your update.

I tried using Nintendo D-pad controllers. Problem is they sit far too high on top of the GP2x to use comfortably, and that is after working out how to secure it properly in the first place.

You could however use the 4-way contact pad, cut the block out (so it isn't too big), use some foil (secured by blu-tack or glue) on each of the four contacts (the carbon doesn't conduct properly on wires, so you need to use tinfoil as the contact), and position the two wires under each of the four contact pads (so you press the rubber bit, down does the tinfoil, completing the circuit. The rubber pad base does not glue, it is too slippy - use sticky foam fixtures. On the top of the 4 rubber contacts, secure (with sticky foam fixture bits) a cardboard (very firm) circle top, and this should work fine. This would give a flat enough final D-pad.

Any queries with the above, let me know and I will try to answer your questions.

I was planning on taking the d-pad, contact pad, and using a cutout piece of the pcb from the GC controller. The PCB isnt thick at all, and would work better since it has real contact pads. Anyone have pictures of an opened gamecube controller? Im havnt got a spare one to take apart right now, just wavebirds..

I have a clear 3rd party wavebird style controller here and the pcb seems to be the perfect size, the problem is theres nowhere to solder wires onto.

You should be able to lightly scrape the covering off the pcb on one of the traces and solder to that. You'd need small wire of course, and a dab of flux may help to flow solder to it.

I've used tact switches in mods such as my NES portable...which is made out of an original NES board. I used tact switches for the built in controller d-pad and A and B buttons. I have to say that they worked great for a controller and it doesnt require much of a push either.

The only potential issues I see is that:

a ) you remove the joystick supplied with the GP2x, and cut away at the Gp2x case. If you mount the GameCube (or similar) pcb in the recess, at just the right height, it should work (assuming you have traced back the right joints on the GameCube pcb part and soldered wires to them. This of course would work, however, it would mean doing some heavy work to the GP2x, and you could end up with a nackered GP2x or making a potential bodge of cutting a hole in the GP2x, if you aren't careful.

or

b ) the finished unit will be too high on the GP2x to be usable (unless you dispense with the D-pad top and use a flat circle of card/coin. Issue with this is that the wires will need to still go through the old joystick hole, which means the wires from the pcb need to be in the centre (which would make the GameCube pcb useless).


I suggest making your own pcb with glue and tinfoil, staple the wires to the right place (wires 1mm apart, so the rubber buttons with carbon (with foil on it) pressed down will make the contact work); rubber buttons on top, and a circle above it to act as a D-pad. This will work great. If you use sticky floor tiles (2 layers), the bottom layer can sit on the GP2x (hole cut for the existing joystick hole) and a flat layer above (with a hole drilled in the right place), this would give you a strong base as the pcb itself. This is the method I have used...

Fantastic work. I saw a site a while ago where someone converted old consoles into portable game machines like this. Very impressive. I will be really interested to see what gadget you make for a D-pad, how it looks, and what you ultimately think of it on the Gp2x. Game on! Fantastic!

Where in the UK can you buy such switches, and how much do they cost?

I should have mentioned that i do plan on removing the stock stick. There is quite a bit of room in there if it was to be removed. The reason im looking at the GC controller is that the D-pad is relativly self contained.



I have no problem with cutting a hole in the gp2x case, or otherwise modifying it. I'll have to measure it when i get home from work, but it may be possible to use the entire top portion of the plastic around the d-pad on the GC controller. That way its just a matter of drilling a hole in the 2x with a hole saw, and moulding the plastic together. Of course i'll have to measure everything after work..

I look forward to hearing how you get on. If the GameCube's D-pad is too big, you could use one from a GBA or old Gameboy (the D-pads are smaller).

I don't know if removing the joystick would cause any problems, and have no idea if there is any impact on the connectors ("C" and "I" in my original post). Shouldn't be any issues, I just don't know for certain. I look forward to hearing from you if all works out ok, and any problems you overcome - whether it works or not, and what you use to elevate the GameCube pcb from the GP2x motherboard (I suppose the old sticky floor tiles would work!). Look forward to your update.

Yeah, i'll have to take some measurements when i get home. I may remove the stock stick tonight if i have time. Another button will have to be added elsewhere for the center push function of the stick since a lot of programs use that + top buttons to quit or menu, but i'll worry about that later.

Thanks You can buy tact switches from where I bought them at www.digi-key.com
I also think Radioshack's may have tact switches...they come in all sizes too. I suggest a small 4mm one. They aren't too pricey either, you can try ebaying it too. As for starting this project, it may not be for a while because I fractured my elbow and currently am in a cast on my soldering arm

I may try doing this mod some time down the road, or even try making a whole new case for it with the proper size for a D-pad. Hey bacteria, by any chance do you have a picture of what the joystick looks like when its off the case itself? I'm just curious to see how you built it.

Oh and the site you are thinking of is probably www.benheck.com or www.portablesofdoom.org with converting the old game systems into portables.

minkster, thanks for the links.

The alternative to the tact switches is the rubber pads used on commercial D-pads (or in remote controls for that matter). Nice and springy, and robust. On my next prototype (in a few day's time), I will make one with these, to compare against.

You should work out some sort of a service to send in your '2x to have a custom pad installed. I'd gladly pay for that, as I don't have a dremel handy nor am I particular dextrous with one.

Not a good idea to send your machine away, too risky for both parties. If you want to upgrade your GP2x, it is best you do it; then if you don't like the result or make a pig's ear of doing it, you only have yourself to blame!

If you make a design which sits on the GP2x itself, as I have been suggesting, there is nothing to remove and you won't need a dremel, etc. This is only relevant if you want to do what Grahf is going to do, in using a full height D-pad in the GP2x and thus having to do surgery on the GP2x itself.

GC d-pad is a little larger than it looks. It still should work, but will be a tight fit. I may have to go with something else, but its a shame because GC controllers are fairly cheap used.

How about this?

Sure, it might be a tight fit, but at least it supports center-click

hahaha,
classic

Actually i removed the old joystick. Came out pretty easy w/ some desoldering braid and a little flux. I still need to measure everything. I plan on putting the original piece of gamecube board directly over top of the original joystick location, and running the wires around the back to solder them. The only problem is that the surface mount resistors/capacitors seen are in the way. They sit about 1mm high, so possibly a piece of double sided tape could be used to both mount and raise the GC pcb.
Any ideas on that?

Update: finally canibalized a gamecube controller. I was sad to wreck such a nice controller It will be a tight fit, but should work ok. For those wondering, i just used a dremel to cut out the PCB. A dremel works well, but be careful not to breath the dust from the board!! After that its a matter of scraping off the coating on the traces, and soldering some suitable gauge wire. The plastic d-pad itself sits a little high as-is, but i think i'm going to shave it down on the bottom so that it doesnt stick out of the gp2x case too far. Comments or questions welcome.

Grahf - nice work to date.

Rather than removing the joystick completely, how come you didn't just cut the legs from the joystick itself and use the reverse legs (as per my illustration) to solder the wires to it?

I would gauge that the GC D-pad is not only a bit tall for the GP2x but also a bit big as a D-pad too. You might like to consider as an alternative a GBA D-pad, or better still, an old GameBoy D-pad (you can still buy them in second hand places sometimes) - these are a bit smaller.

One way to raise the board above the transisters is to use sticky floor tiles! - adhesive and sticky, plastic (so no conductor), solid.

I look forward to your updates on developements. Keep it up!

Hey grahf, that's sounding really good. I wish I could Dremel without running the risk of limb loss, then I could give this a shot myself

Anyway, keep us updated!

fishybawb - you could make your own, with card, tinfoil, wires, just as effective, can be mounted on the front of the GP2x (above hole), use the D-pad rubber keys, and mount a piece of circular card (over the rubber keys) to act as the D-pad. This works, looks reasonable, no Dremelling!

Bacteria, I get the feeling that you really like sticky floor tiles.

FluffyPanda - everything has its uses!

It's a good idea, but I really don't like the look you get from sticky floor tiles and blu-tac. I've been looking at my old Gameboy's d-pad with murderous intent... Maybe I'll get brave with a Dremel and just hope I don't hit an artery

Edit: Typo

me too

@grahf: Keep us updated, its looking good so far.

How will you handle center push if you use a hacked up GC gamepad?