bme680-driver

Table of Contents

• Overview
• Features
• Repository Structure
• Installation
• Quick Start
• Units & Precision
• License

Overview

A type-safe, no_std Rust driver for the Bosch BME680 environmental sensor. It provides high-level access to temperature, humidity, atmospheric pressure, and gas resistance measurements using the embedded-hal traits.

Features

• Typestate Pattern: Prevents illegal sensor states and ensures correct initialization.
• Fixed-Point Arithmetic: High-performance compensation formulas without the need for a floating-point unit (FPU).
• Type-Safe Units: Uses custom types like Celsius and Milliseconds to prevent unit-mixing errors.
• No-Std: Suitable for all bare-metal microcontrollers (STM32, ESP32, AVR, etc.).

Repository Structure

└── bme680-driver/

    ├── src/

    │   ├── lib.rs

    │   └── calc.rs

    ├── .examples/

    │   └── stm32f407.rs

    ├── .cargo/

    │   └── config.toml

    └── Cargo.toml

Installation

Add this to your Cargo.toml:

[dependencies]

bme680-driver = "0.1.0"

Quick Start (STM32 Example)

use bme680_driver::*;

// Initialize I2C and Delay from your HAL...
let bme = Bme680::new(i2c, 0x76);
let mut bme = bme.init(&mut delay).expect("Failed to init BME680");

let mut config = Config {
    osrs_config: OversamplingConfig {
        temp_osrs: Oversampling::X1,
        hum_osrs: Oversampling::X1,
        pres_osrs: Oversampling::X1,
    },
    iir_filter: IIRFilter::IIR0,
    gas_profile: GasProfile {
        index: GasProfileIndex::Profile0,
        target_temp: Celsius(300),
        wait_time: Milliseconds(300),
    },
    ambient_temp: Celsius(2300),
};

bme.configure_sensor(&mut config).unwrap();

loop {
    let data = bme.read_new_data(&mut delay).unwrap();
    
    // Use helper methods to format data (no floats needed!)
    let (temp_int, temp_frac) = data.temp.split();
    let (pres_hpa, pres_dec) = data.pres.as_hpa();
    
    // Log formatted data (e.g., via defmt)
    defmt::println!("Temperature:    {}.{} °C", temp.0, temp.1);
    defmt::println!("Humidity:       {}.{} %", hum.0, hum.1);
    defmt::println!("Pressure:       {}.{} hPa", pres.0, pres.1);
    defmt::println!("Gas Resistance: {}  Ohm", data.gas.0);
    defmt::println!("");
    
    // Dynamically update heater profile with current ambient temperature.
    // We access the raw value (.0) to wrap it into Celsius.
    bme.set_gas_heater_profile(config.gas_profile, Celsius(data.temp.0)).unwrap();
    
    delay.delay_ms(5000);
}

Units & Precision

License

Licensed under either of:

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)

• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.