Gamecube rumble motor/analog triggers in joystick mod

Warp_Rattler · Post by **Warp_Rattler** » Wed May 13, 2009 3:10 am

Warning: Possibly idiotic electronics noob question below. I can handle a soldering iron but know little to nothing about electronics theory. In attempting to educate myself online, I see this mysterious chasm between gradeschool-level explanations on just what a resistor is, and then people who were either born with a complete understanding of electronics, or were electronic engineering majors IRL and know these things as a matter of course. I turn to you, shmups community, for edification on an issue which I don't at all understand but which I'm sure is idiotically simple to the right person.

I'm currently in the process of replacing the stock buttons and stick in my Agetec Dreamcast arcade stick with Sanwa parts, a process that's taking longer than I expected due to the crappy nature of my off-brand Dremel substitute I'm using to cut and smooth the plastic and widen the metal faceplate to accomodate the buttons (it was only $15; I suppose one DOES get what one pays for).

I've removed the Dreamcast controller PCB from the stick and intend to mount a 15-pin connector inside the VMU slot on the case, and then build adapter boxes for PS1/PS2, Dreamcast, and Gamecube/Wii. While the PS1/2 and Dreamcast boxes won't be too difficult (I'll just use a PS1 controller without all the fancy analog garbage, and the PCB from the Agetec stick couldn't be simpler to hook up), I'm a little confused about a few things with the third party Gamecube controller I intend to cannibalize for this project.

My first question involves the rumble motor. I have no use for it; how would I go about removing it from the PCB? Is it something that can simply be desoldered, or do I have to then bridge the resulting open connection? Will games still attempt to send rumble signals to the controller, and is there any way of making the game sense that the controller doesn't even have a rumble feature (does Gamecube/Wii even do that?), or is that a function within the controller's encoder chip?

Next, the analog triggers. I think I've figured this out, but I'd like a bit of clarification anyways. It looks like there are two components to the triggers: an analog switch that detects the varying degrees of pushed-down-ness of the triggers, and a button at the bottom to register a completely pushed-in trigger. Now, if I'm making a purely digital controller for Ultimate Shooting Collection, Shiki III, fighting games etc., am I right in assuming I could skip the analog slider entirely and just solder the joystick button connections to the two buttons that indicate that the trigger has been entirely depressed? Furthermore, to save a bit on space could I simply desolder said analog sliders?

Finally, what about the C-stick? In an attempt to keep this project as clean as possible I'd really prefer not to have it and its small attached PCB rattling around the project box for the adapter; could I desolder it without any adverse consequences, or does the Gamecube throw an error when it's trying to poll the C-stick and finds nothing?

On a slight sub-tangent, if I'm intending to play a variety of fighters and shmups on the PS2 with this joystick, am I going to run into a lot of problems using a PS1 controller for the adapter? I thought I had read something about certain games not working without a Dual Shock 2 attached; seeing as analog buttons wouldn't really be beneficial to the fighting and shooting genres, is this something I would really have to worry about?

Apologies again if these are amazingly simple questions.

antron · Post by **antron** » Wed May 13, 2009 4:22 am

Just cut the motors off. It will still send voltage to but nothing will happen. The GC will have no idea it's gone.

If you cut out the analog triggers or c-stick variable resistors you run the risk of having it always sense a direction. When in doubt hot-glue it out of the way.

If you use a PS1 controller use a sony one with analog controllers to ensure compatibility with a PS2. You do not actually need the analog sticks for any shmups (you may need select to insert credits in arcade ports).

Are you using separate or common grounds?

Warp_Rattler · Post by **Warp_Rattler** » Wed May 13, 2009 3:47 pm

I was thinking common grounds would be the simplest. Also, for rarely used buttons (such as Select on the PS2) I thought to just mount a small Radio Shack pushbutton on the adapter box itself to keep things a bit cleaner on the joystick end.

So when in doubt with the more complicated things, it seems best to just tape/glue them out of the way, then. I'm not sure if I have a spare Dual Shock pad to open up--aren't the soldering points on those woefully small?

antron · Post by **antron** » Wed May 13, 2009 4:18 pm

Are you sure all the pads you plan on hacking are common ground?

I hacked sony "Dual Analog" controllers, and it was easy.

Warp_Rattler · Post by **Warp_Rattler** » Thu May 14, 2009 1:58 am

Sorry, I thought you were asking if I was going to wire the grounds to the buttons inside the stick separately or in tandem.

After looking at the Gamecube PCB it LOOKS like it's a common ground for all buttons, but I can't tell with 100% certainty. It could be that the d-pad area shares one ground and the face buttons have their own. I need to figure out in what box in the garage I've stashed the multimeter so I can have a look.