D-pad Hack


Series-8

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Joined
Nov 4, 2005
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299
SNES or PS style 'D'-pad.

First you would need to drill out the plastic casing around the joystick as it is too small
to have a pad put thru it.

I think a small PCB with the microswitches (would have to have 8) and the "+" style plastic part would have to be a single module with connection pins facing downwards.
To act as a 'drop-in' replacement.

The replacement module is basically a complete joypad assembly, ready to be soldered into place once the old joystick is desoldered.

I don't think this is something that can be thrown together, a really good design is needed. Someone with EE experience would make a mint if they could build this kind of thing.
 
I've been thinking of the same thing, but what about center click? I checked the available area around the stick hole and there doesn't seem to be much clearance for even the smallest of microswitches. That said, there may be room between the power and battery LEDs.

I'm not brave enough to bust out the soldering iron yet though. I've been thinking about trying to get a Neo Geo CD Pad click stick in there, but there's probably no way that would work.
 
The hardware would be easy enough to make. You only need to make a small home made circuit board to mount the microswitches, and mount it directly on top of the gp2x board. Small wires can be run to the through-holes on the 2x pcb.


Most console gamepads use a carbon pad setup instead of microswitches, which would be a better setup in my eyes. The problem with using a board from one of those, is that they only have 4 contact pads. The 2x hardware is 8-way, so you never get a situation where both Up and Left are contacted at once (you get the specific diagonal). Software would have to be altered slightly so that a 4-button d-pad would work. The pushbutton would also be lost, but its not critical.
 
I have an old game pad for my PC lying around that has a center click on the dpad, I'll take it apart when I get a chance and see how easy it might be to adapt it.
 
Indeed there is insufficient room, for a D-pad without DRILLING OUT the joystick area totally. Also I'm talking some REALLY small microswitches.

Surface mount ones, like these:
Switches

Or you could use the old rubber/carbon conductor pad design, with a really well laid out
exposed PCB.

I wonder what possesed GPH to not use a Dpad...
 
Indeed there is insufficient room, for a D-pad without DRILLING OUT the joystick area totally. Also I'm talking some REALLY small microswitches.

Surface mount ones, like these:
Switches

Or you could use the old rubber/carbon conductor pad design, with a really well laid out
exposed PCB.

I wonder what possesed GPH to not use a Dpad...

Holy crap, those are frickin' tiny! Half a millimeter thick will fit under there.
 
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Indeed there is insufficient room, for a D-pad without DRILLING OUT the joystick area totally. Also I'm talking some REALLY small microswitches.

Surface mount ones, like these:
Switches

Or you could use the old rubber/carbon conductor pad design, with a really well laid out
exposed PCB.

I wonder what possesed GPH to not use a Dpad...

Holy crap, those are frickin' tiny! Half a millimeter thick will fit under there.
A bitch to solder I bet.
 
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Maybe not too bad, but I think it'd be far too much work for a prototype. I think the carbon pads would be the best way to go. I've already sacrificed a few Dual Shock 2 pads for a homebuilt arcade control, and it seems it may not be too hard to cram one in the GP.

The problem of 4-way vs 8-way was already mentioned, but I think a proof of concept may be in order for determining how big a problem this is going to be. I'll do a mock up drawing later and show you guys what I have in mind.

Any way it goes, it will definitely require drilling out the front bezel a bit (or a lot, depending.)
 
Well I was thinking about ripping apart a (cheap) calculator/TV remote for the carbon pads (there are some really small ones and putting 8 'grids' on PCB, Assuming the microswitch idea is too much of a bother.

I've never liked that 'spongy' pad setup...but whatever works.

Assuming someone could find a decent source of carbon pads, this mod could be fairly cheap as all it really needs is a exposed PCB and some strong thru-hole pins and the pad itself.
 
Upon further inspection, there is *very* little clearance in there. I believe a drop-in replacement or riser board for the existing unit would be very difficult. I think a mod of the existing unit may be better, but maybe impossible.

Anybody have a broken Neo Geo Pocket laying around?
 
can someone explain the technical aspects of how a D-Pad will actually WORK on a 8 way directional joypad? with joysticks you move them across to the left to hit left..with a d pad to press down left to hit left..so how will it work on a joystick, stick.
 
Think of a joystick as a d-pad with a stick in it. Actually, one of the earlier consoles (Sega possibly?) had a d-pad with a screw hole in the middle of it into which you could screw a small joystick.
 
From my experience, most arcade joysticks are 4-way types, though some 8-ways are around.

We're talking about a drop-in replacement though, so a 4-way dpad may work if some magic is done in the pcb design part of this. Basically, 4 carbon pads like a standard dpad, but designed so that when two side-by-side pads are activated it sends as a diagonal instead of the two separate directions.

Trouble is, I don't know if the software side of the house will like that sort of input.

The alternative is to design an 8-way dpad with pin compatibility to the current one. The cramped interior of the gp2x may not allow for this at all, but if it does, it'll have to be a smaller dpad then we're used to.

Tonight I'll be sacrificing a GBA trying to further this idea. To be honest, it may be easier to rotate it 45 degrees.
 
Direct replacement would be best but it's doubtful that such stick does exist.

The pins had to be the same and theirs electrical meaning.

Modding the original gp2x's one is best bet or using small adaptor to be able to solder another. D-pad is no solution because of needed drilling of front panel. It's pity but there aren't easy solutions...
 
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