This guide will show you how to transform a Raspberry Pi Pico into a custom game controller compatible with the Nintendo Switch using the open-source firmware GP2040-CE.
Keep in mind the controller only works with Nintendo switch in docked mode!
- Added example to use a joystick module
- Initial release
There is a step by step youtube video available at https://www.youtube.com/watch?v=Jl17h7Sx4sw
- No programming required
- Supports multiple consoles (although we’ll focus on the Switch)
- Easy configuration through a built-in website on the Pico:
- Backup and restore configurations
- Customize buttons, rotary encoders (knobs), and joysticks
- Create macros (one button triggers multiple inputs)
- Supports various optional add-ons
- Quick setup — can be done in under 30 minutes
| Item | Notes | Price |
|---|---|---|
| Raspberry Pi Pico (RP2040) | Buy official; with headers if possible | ~€7 |
| Breakout board (optional) | Simplifies connections, highly recommended | ~€5 |
| Buttons | Any buttons or micro switches | Varies |
| Wires, terminals | Various connections for buttons | Varies |
- Download the GP2040-CE firmware.
- Put the Pico into USB mode.
- Flash the firmware.
- Configure the device for Switch mode.
- Test the controller.
For this example, we’ll wire five buttons:
- Right
- Left
- A
- B
- S2 (used to boot the Pico into configuration mode)
You can wire more buttons (e.g., Up, Down) similarly for your final design.
| Button | Wire 1 | Wire 2 |
|---|---|---|
| Right | GND | GP04 |
| Left | GND | GP05 |
| A (B1) | GND | GP06 |
| B (B2) | GND | GP07 |
| Special 2 (S2) | GND | GP17 |
- The GND (ground) pin is flexible and can be shared across buttons.
Simply connect the wires to the headers and screw them down.
- Visit the GP2040-CE downloads page.
- In the Raspberry Pico section, click Download.
- This will download a file like GP2040-CE_X.X.X_Pico.uf2.
- Find the BootSel button (near the USB port).
- Unplug the Pico.
- Open Windows Explorer.
- While holding the BootSel button, plug the Pico into the USB port.
- You should see a new removable drive named RPI-RP2.
- Drag and drop the GP2040-CE_X.X.X_Pico.uf2 file into the RPI-RP2 drive.
- The Pico will automatically disconnect and flash the firmware.
- Unplug the device.
- Hold the S2 button and plug the Pico back into the USB port.
- Open your browser and navigate to http://192.168.7.1.
- Go to Settings.
- In the Input Mode Settings, set Current Input Mode to Nintendo Switch.
- Press Save, and then click Reboot.
- Click Console to test the configuration.
- Go to https://hardwaretester.com/gamepad.
- When you press a button, the controller should be recognized as POKKEN CONTROLLER.
- Button presses (like A or directional inputs) will be reflected in real-time.
With this setup, you’ll have a fully functional Nintendo Switch controller that you can easily customize to fit your needs!
It is also possible to use PlayStation-style mini joystick controllers. This section explains how to add them.
An example of these kind of modules is seen below
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There is a step by step youtube video available at https://www.youtube.com/watch?v=DGvlZDRiA8w
For this example, we’ll wire the analog axes of a PlayStation-style mini joystick:
- X-Axis (Left/Right Movement)
- Y-Axis (Up/Down Movement)
Both axes are analog, so they need to be connected to analog-capable pins on the microcontroller.
| Component | Wire 1 |
|---|---|
| X-Axis (Left/Right) | 26 |
| Y-Axis (Up/Down) | 27 |
| GND | GND |
| 5V | 3V3 |
-
The PCB is marked for 5V, but the Pico operates with a 3.3V signal. Be sure to connect it to the 3.3V pin to prevent any abnormal readings. This is because the GPIO pins for the RP2040 utilize 3.3V logic and are not 5V-safe.
-
The X-Axis and Y-Axis are analog inputs and should be connected to analog-capable pins (ADC pins), such as GP26, GP27, GP28, or GP29.
- Unplug the device.
- Hold the S2 button and plug the Pico back into the USB port.
- Open your browser and navigate to http://192.168.7.1.
- Go to Configuration (1) menu
- Select Add-Ons configuration
In the analog addons tab
- Enable the addon
- In Analog Stick 1 X Pin set the dropdown value to 26 (pin)
- In Analog Stick 1 Y Pin set the dropdown value to 27 (pin)
- Enable Force circulation
- Enable Autocalibration
- Enable Analog smoothing
Very important to save the changes, scroll down to the bottom and click the Save (1) button
Press Save, and then click Reboot.
Click Console to test the configuration.
You can invert the direction of the Joystick in the configuration menu by selecting the Axis you want to invert in the dropdown in the Analog Stick 1 Invert settings.
You can enable a second joystick by following the same connections as the first joystick, but use one of the other ADC pins, such as GP28 or GP29.
Follow the same configuration steps as for Joystick 1, but make sure to configure the Analog Stick 2 fields accordingly.
- Invert Axis: Choose if you want to flip the X or Y axis of Analog Joystick 2 (or both).
- Deadzone Size (%): Set the percentage for the dead zone. This is the area around the center where small movements won't be detected, preventing accidental input.
- Forced Circularity: Constrain the analog joysticks to move within a perfect circle. This can be useful for some games, but may cause issues in games that expect the sticks to move outside of the circle.
- Auto Calibration: Automatically re-centers the analog joysticks. It reads the joystick's center position when the device is powered on and adjusts accordingly to correct any drift until the next power cycle. This is useful for joysticks that experience drift over time.
- Error rate: You can change or experiment with the error rate to modify the accuracy if the default is not ok.
You can easily use other caps than the PS2 controller for example here is a longer version
