Adafruit OLED Bonnet Demo

A minimal Rust application for testing out the Adafruit 1.3” OLED Bonnet (SSD1306) with a Raspberry Pi (5).

🎨 Overview

This project demonstrates:

• Using linux-embedded-hal and rppal for I2C and GPIO access.
• Drawing on the OLED display with embedded-graphics and ssd1306.
• Handling button/joystick inputs.
• Exiting SIGINT cleanly via ctrlc.

🔌 Hardware Setup

Adafruit 1.3" OLED Bonnet

• Plug the bonnet onto your Raspberry Pi's GPIO header.
• Confirm that the bonnet's SDA/SCL pins map to the PI's I2C1.
• Typically, this is on pins 3 (SDA) and 5 (SCL).

Enable I2C

• Run sudo raspi-config, go to Interface > Options > I2C enable it, then reboot.
• Confirm the device with:

$ sudo i2cdetect -y 1

# This should output something like:
#      0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
# 00:                         -- -- -- -- -- -- -- -- 
# 10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
# 20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
# 30: -- -- -- -- -- -- -- -- -- -- -- -- 3c -- -- -- 
# 40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
# 50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
# 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
# 70: -- -- -- -- -- -- -- --    

Important

The demo uses 0x3c per default. You might need to adjust the code, if this differs.

Buttons and Stick

• This bonnet has 7 GPIO-based inputs (2 buttons, 4-direction joystick, and pressing the joystick).
• In the demo, we assume these pins:

Button A        -> GPIO 5
Button B        -> GPIO 6
Joystick Left   -> GPIO 27
Joystick Right  -> GPIO 23
Joystick Up     -> GPIO 17
Joystick Down   -> GPIO 22
Joystick Press  -> GPIO 4   # Not used in code

Note

Check Adafruit's documentation or pinout if your hardware differs for your setup.

⚙️ Software Requirements

• Rust
• Cargo
• I2C Tools (i2c-tools, libi2c-dev on Debian-based distros)

Make sure you can build Rust projects on your Pi or cross-compile from another machine. You can find the installation documentation for Rust and Cargo here.

🚀 Running the Demo

1. Clone this repository:

$ git clone https://github.com/adrior11/bonnet-demo-rs.git

2. Build and Run:

$ cargo run

🕹️ Usage

Controlls

• Joystick: Move the circle around (left, right, up, down).
• Button A: Redraw the circle if needed.
• Button B: Clear the display.

Exiting

• Press Ctrl+C in the terminal to trigger a cleanup routine that clears the display and shuts down the application.

📁 Project Structure

.
├── ...
├── Cargo.toml      # Project metadata & dependencies
└── src
    ├── main.rs     # Main logic: sets up display, pins, main loop
    └── position.rs # Position structure with movement logic

License

This project is available under the MIT License.