D-pad Construction...


Modder & Portablizer
Jan 12, 2006
Hampshire, UK.
I haven't got a GP2x at the moment as I sent it back, but will get another one over the next few weeks. I did however have a play with my old one for a few days, so I am familiar with the GP2x.

I have read stacks of posts on the D-Pad subject, and have taken a couple apart from controllers using D-Pads, and was wondering if the following theory would work in practice:

1) Acquire the rubber button-presser pads (with carbon circle) and D-Pad from a controller (eg old Nintendo gameboy / N64, etc).
2) Make a custom board out of an old piece of plastic sheet (fairly thick so it is strong and doesn't bend easily). The carbon in the rubber-presser pads just completes the circuit of two contacts (simple and effectively) and the rubber surround acts as a spring to take the carbon away from the contacts when not depressed.
3) Use some aluminium foil to craft the contacts for the carbon button-presser pads - it can be a straight piece of aluminium foil for each of the four buttons, with a 1mm divide to break the circuit (the carbon will complete the circuit when pressed). The rubber button-presser (containing the carbon) can be stuck in place (ensuring the finished product houses the D-Pad correctly).
4) Join each end of the four pairs of foil to wires.
5) On the internal diagram of the 8-way joystick, it appears that contact is made when the joystick is moved onto one of the 8 contacts (logically!), which means that (presumably) one of the contacts is universal for the joystick; if this is right, remove the top of the joystick (redundant), and solder one from each of the four pairs to wires to the pin which connects to this joystick, and solder (or use sticky tape instead of solder) each of the other wires from the pairs to their respective connections on the internal contact inside the joystick (up,down,left,right). If this logic is right, can someone please post which pin on the 8-way joystick does what please?

As the joystick top would be off the unit, making a hole in the D-Pad should give access to the central button if required. The space acquired from not having the joystick top should give the space required for the wires, and the D-Pad itself (once a suitable housing has been crafted to fit the shape of the joystick area on the GP2x), could be blu-tacked onto the space directly onto the GP2x. Blu-tack should be strong enough, is removable, and provides a good seal.

This is all theory at the moment, but would this work? The GP2x primarily uses 4 way, if you use the GP2x for movies, mp3 and emulation gaming, it is unlikely that 8 way is needed anyway. I don't know about you guys, but I can use a D-Pad far quicker and with far more precision than a mini joystick!

The other advantage of this process is that it wouldn't be difficult to revert the GP2x back to its joystick status again, if required.

Comments? Would this work, can anyone suggest improvements, anyone want to try it and post back results??
Foil? Plastic sheet? Ghetto?

plastic sheet with contacts is a bad idea. like shose cheap china made keyboards, look how long they last... and thier made with the plastic and carbon contacts. we just need to find a joystick replacement or find someone who can make a decent amount of them so we can all pitch in and buy a better one. i think someone actually found the joystick were using right now on some website - like $10.00. If you think you can make something that small to fit on that board, i bow to you sir.
I know it sounds a little Heath Robinson, however, a suitable piece of plastic sheet can be cut out from something like an old keyboard backing, or whatever. Aluminium foil - is a conductor of electricity (and we are only talking about a very very tiny voltage), is flat, and mallable. The idea isn't to make something as small as the existing joystick, but build something on top of the GP2x which feels comfortable on a D-Pad, and just have some thin wires going inside the GP2x to connect to the joystick contacts (if the top of the joystick is removed, the contacts are exposed, there is no need for the joystick shaft, so the D-Pad will also lay flat on the GP2x) - this is just providing a different set of contacts without requiring soldering skills (apart from de-soldering the top of the joystick connection from the motherboard presumably), or having an understanding of how the motherboard works (which I don't have).

If someone knows which contacts do what for the joystick on the motherboard (ie which circuits to connect to for up, down, left, right, centre button; please post them!

As I said, I would welcome all comments and suggestions. Sometimes a simple solution (like this one) can be effective - however I don't want to destroy my GP2x when I get one again, by tinkering on a theory - that is the benefit of a discussion forum after all - to gain opinion of others, evolve a concept, and build it.
Good thinking though! Keep the ideas flowing!

I would totally need the cornor though, any type of shooting game will use cornors. Atari joystick would respond to a UP\RIGHT cornor combo, DPAD needs to do the same.