How would you do it ? Transforming a keyboard into a game controller.

[freeman7]

Hello,

I would like to convert the corsair k100 keyboard with optical switches into a fighting game controller with 11 buttons, I am not sure what's the correct way to go about this project, any help would be really appreciated.

The main challenge is how to take inputs from the switches into the keyboard PCB, i am no PCB engineer but i have thought of two ways:

1) cutting the 11 PCB parts from the PCB and rewiring them somehow via a module to the main keyboard PCB.
2) create a custom PCB for the 11 buttons, with its own optical sensors (take those from the keyboard PCB ?) and connect it to the keyboard PCB.

this is the result that I want to achieve (photo at the bottom)



Maybe you could think of easier ways or point me in other directions.
Many thanks

[Leslieann]

This is not only unnecessarily destructive, but expensive and overly complicated.

Forget starting with a keyboard at all, especially if all you want is the controller out of it, build your case and wire the switches to an Arduino Pro Micro or Teensy with QMK firmware.
There's tons of guides on doing exactly what you want this way, either controllers or hand wired keyboards, they're all done similarly.

I bought a 5 pack of these Arduinos for like $20.

[Findecanor]

With optical switches, there is a LED and a optical sensor of some kind on the PCB under each switch module, so you can't just remove the switches and wire them up. You would need a PCB for those components to sit on and to provide power to the components.

But do ask yourself if you really need optical switches.  Compared to mechanical switches (with electro-mechanical contacts), they tend to be smoother and faster. But I'd think that there are mechanical switches that are smooth and fast enough.

BTW. For mechanical Cherry MX - type keyboard switches there are now adapters available for putting them inside arcade switch enclosures that can be mounted in circular holes.
One brand is Gamerfinger, but I think there is at least one more out there.

[freeman7]

This is not only unnecessarily destructive, but expensive and overly complicated.

Forget starting with a keyboard at all, especially if all you want is the controller out of it, build your case and wire the switches to ancor Teensy with QMK firmware.
There's tons of guides on doing exactly what you want this way, either controllers or hand wired keyboards, they're all done similarly.

I bought a 5 pack of these Arduinos for like $20.

Hello, thanks for your response, the goal from the project is to take advantage of the 0.4ms latency of the k100, and it's fast optical switches, making this project the first optical fighting game controller (and fastest), it's just that there is nothing to wire things to, as the sensors sit on the pcb itself, so i am looking for a way to use those optical sensors.

[freeman7]

With optical switches, there is a LED and a optical sensor of some kind on the PCB under each switch module, so you can't just remove the switches and wire them up. You would need a PCB for those components to sit on and to provide power to the components.

But do ask yourself if you really need optical switches.  Compared to mechanical switches (with electro-mechanical contacts), they tend to be smoother and faster. But I'd think that there are mechanical switches that are smooth and fast enough.

BTW. For mechanical Cherry MX - type keyboard switches there are now adapters available for putting them inside arcade switch enclosures that can be mounted in circular holes.
One brand is Gamerfinger, but I think there is at least one more out there.

Hi, yes, i really need to use those optical switches for their speed, i would like to build the fastest fighting game controller, i am aware of the cherry mx, infact my current controller has the MX low profile speed switches, but i really would like to attempt this project.

[Findecanor]

You know the "speed advantage" is mostly thin air and marketing fluff, right?

Anyway ...

Yeah, do study the PCB and design a copycat footprint in a EDA program. Build your own, desolder components from the keyboard PCB and replace those with wires to your PCB(s).
You would need soldering equipment for surface-mount components, and magnifying equipment, because it is awfully fiddly.

I think one of the Cherry MX - in arcade-switch variants I've seen used a PCB at the bottom. Perhaps you could design a replacement for that PCB. The Corsair OPX seems to have Cherry MX dimensions otherwise, so it might fit. But the switch needs to fit securely in the housing. Because they are optical, they are not soldered to anything.

[freeman7]

Hi,

Thank you this your very informative response.

In fighting games, at a competitive level, speed is really not thin air.. you feel the difference in the ability to execute certain mechanics and confirms that have a tight window of confirmation and just overall reactions when playing on low input lag controllers + fast buttons, having a controller on an even faster pcb + optical switches is definitely a project that would interest a lot of competitive players.

Just a thought.. instead of desoldering those sensors and placing them on the new pcb, can i just buy those optical pcb sensors somewhere? do u know what those electronic parts are called ?.

Many thanks