DualSense Controller Interface for Raspberry Pi Pico 2W

This project enables Bluetooth HID host functionality on the Raspberry Pi Pico 2W, allowing it to connect to a PlayStation 5 DualSense controller and read real-time inputs through an easy-to-use C API.

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Features

• Bluetooth HID Host implementation for DualSense controller
• Real-time monitoring of all controller inputs (buttons, joysticks, triggers, D-pad)
• Joystick axis normalization with configurable deadzone
• Normalized trigger (L2/R2) axis values (0–100)
• D-pad directional values (0–8) and button queries (square, cross, circle, triangle)
• Optional polling-frequency counter for performance diagnostics
• Simple API functions exposed in DS5_hid_host.h
• Sample main.c demonstrating usage and onboard LED feedback

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Hardware Requirements

1. Raspberry Pi Pico 2W module
2. PlayStation 5 DualSense controller
3. Micro‑USB cable for programming and power (or VBUS/VSYS pins)

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Software Requirements

• Visual Studio Code (or another C/C++ IDE)
• Raspberry Pi Pico SDK (version ≥ 2.1.1)
• ARM/RISC‑V toolchain (GCC 14.2Rel1 or compatible)
• CMake (version ≥ 3.13)
• cmake, make, and git available on your PATH

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Repository Structure

Raspberry-pi-pico-2W-DS5-host/
├── btstack_config.h       # BTstack settings
├── CMakeLists.txt         # Build configuration
├── DS5h_hid_host.c        # HID host implementation and API
├── DS5_hid_host.h         # Public header with API declarations
├── main.c                 # Example usage demonstrating the API
├── pico_sdk_import.cmake  # Generated project file
└── README.md              # This documentation file

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Setup Instructions

1. Clone the Repository

git clone https://github.com/Pim-Hartendorp/Raspberry-pi-pico-2W-DS5-host.git
cd Raspberry-pi-pico-2W-DS5-host

2. Initialize the Pico SDK

This is usually handled by the Pico extension for VS Code. If not:

• Set the PICO_SDK_PATH environment variable:

  export PICO_SDK_PATH=/path/to/pico-sdk

3. Build the Project

The Pico extension may auto-build CMake. if not, select a kit using this comand in the VSCode search bar:
> CMake: Select a Kit after this press ctrl + shift + B to build the project.

Otherwise:

mkdir build && cd build
cmake ..
make -j$(nproc)

The output .uf2 file will be in the build/ directory.

4. Flash to the Pico

1. Hold BOOTSEL on the Pico and connect via USB.
2. It appears as a mass-storage device.
3. Copy the generated .uf2 file onto it.
4. The Pico reboots and runs the HID host firmware.
5. Reconnect to access console output over USB (if needed).

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Usage

1. Put the DualSense into pairing mode (hold PS + Create until the light bar blinks rapidly).
2. The Pico will auto-connect using the address passed to DS5_init() in main.c.
3. Call the API functions to read joystick, button, trigger, and D-pad states.

Example (main.c)

#include <stdio.h>
#include <stdbool.h>
#include "DS5_hid_host.h"

int main(void) {
    const char *remote_addr = "01:23:45:67:89:AB";  // Replace with your controller's MAC
    stdio_init_all();
    DS5_init(remote_addr, false);

    while (true) {
        int8_t lx = DS5_left_joystick_X_axis(5); // the deadzone is 5 percent in this case so the outputs values at 6
        int8_t ly = DS5_left_joystick_Y_axis(5);
        bool cross = DS5_cross_button();
        printf("LX=%d, LY=%d, Cross=%d\n", lx, ly, cross);
        tight_loop_contents();
    }
    return 0;
}

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API Reference

Function	Description
int DS5_init(const char *addr, bool f);	Initialize HID host and connect to addr.
int8_t DS5_left_joystick_X_axis(uint8_t dz);	Left stick X (-100…100) with deadzone dz.
int8_t DS5_left_joystick_Y_axis(uint8_t dz);	Left stick Y (-100…100) with deadzone dz.
int8_t DS5_right_joystick_X_axis(uint8_t dz);	Right stick X (-100…100) with deadzone dz.
int8_t DS5_right_joystick_Y_axis(uint8_t dz);	Right stick Y (-100…100) with deadzone dz.
uint8_t DS5_Dpad_value(void);	D-pad direction (0…8).
bool DS5_square_button(void);	Square button pressed?
bool DS5_cross_button(void);	Cross button pressed?
bool DS5_circle_button(void);	Circle button pressed?
bool DS5_triangle_button(void);	Triangle button pressed?
bool DS5_L1_button(void);	L1 button pressed?
bool DS5_R1_button(void);	R1 button pressed?
bool DS5_L2_button(void);	L2 button pressed?
bool DS5_R2_button(void);	R2 button pressed?
bool DS5_create_button(void);	Create/Share button pressed?
bool DS5_options_button(void);	Options/Menu button pressed?
bool DS5_L3_button(void);	L3 (stick press) pressed?
bool DS5_R3_button(void);	R3 (stick press) pressed?
bool DS5_ps_button(void);	PS/Home button pressed?
bool DS5_touchpad_button(void);	Touchpad click pressed?
uint8_t DS5_L2_axis(void);	Normalized L2 axis (0…100).
uint8_t DS5_R2_axis(void);	Normalized R2 axis (0…100).

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Troubleshooting

• Controller not connecting: Ensure the DualSense is in pairing mode and the MAC address is correct.
• High latency or low frequency: Enable the frequency counter by passing true to DS5_init() (observed ~780–800 Hz).
• Build errors: Verify PICO_SDK_PATH and toolchain versions.

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License

This code (and any modifications) is distributed under the following terms, as originally authored by BlueKitchen GmbH:

BlueKitchen Non‑Commercial BSD‑Style License
(Full text in LICENSE)

You may redistribute and modify the source as long as you retain the copyright notice, conditions, and disclaimer. Any use must be for non‑commercial, personal benefit only.

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Acknowledgements

• BlueKitchen GmbH: HID host implementation adapted from the Pico Keyboard example.
• Raspberry Pi Foundation: Pico SDK and example code.