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Β§π‘οΈ dht11-driver
Β§π Table of Contents
- π Overview
- π¦ Features
- π Repository Structure
- π Getting Started
- π Technical Details
- π License
Β§π Overview
This project provides a highly optimized, no_std Rust driver for the DHT11 temperature and humidity sensor.
Designed with safety and precision in mind, it supports both hardware-accelerated timing via ARM DWT and a portable software-based timing engine.
Β§π¦ Features
| Component | Description |
|---|---|
| Agnostic | Platform-independent core; works on any MCU via embedded-hal. |
| Safety | Uses Typestates to prevent reading from an uninitialized sensor. |
| Precision | DWT hardware support for sub-microsecond pulse measurement. |
| Observability | Native integration with defmt for zero-overhead logging. |
Β§π Repository Structure
βββ dht11-driver/
βββ src/
β βββ lib.rs # Core driver and Typestate logic
β βββ examples/ # STM32F407 reference implementations
β βββ stm32f407_dwt.rs
β βββ stm32f407_no_dwt.rs
βββ .cargo/
β βββ config.toml # Runner & Linker settings
βββ Cargo.toml # Feature gate definitionsΒ§π Getting Started
Β§1. Installation
Add the library to your Cargo.toml:
[dependencies]
dht11-driver = "0.1.0"Or use the cargo CLI:
cargo add dht11-driverΒ§2. Hardware Setup (STM32F407)
1. Sensor Connection: Connect the DHT11 DATA pin to PA0 on your STM32F407 Discovery/Black-Pill board.
2. Pull-Up Resistor: The DHT11 uses a single-wire bidirectional protocol. You must configure the pin as Open-Drain. A physical 4.7kΞ© to 10kΞ© pull-up resistor to VCC is highly recommended for signal integrity.
Running the Examples This repository includes pre-configured examples using probe-rs. Use the following commands to flash your board:
| Mode | Command | Active Features |
|---|---|---|
| High Precision | cargo run βexample stm32f407f_dwt βfeatures use-dwt | use-dwt, use-defmt |
| Universal Timing | cargo run βexample stm32407f_no_dwt | use-defmt |
Β§π Technical Details
Typestate Safety
To eliminate logic errorsβsuch as attempting to read data before the sensor has finished its 2-second power-on stabilizationβthis driver implements the Typestate Pattern. The sensor object transitions through different types in your code:
// 1. Create the driver in 'Uninitialized' state
let dht11 = DHT11::new(pin, clocks.sysclk());
// 2. Initialize
// This consumes the old state and returns the 'Initialized' version
let mut dht11 = dht11.initialize(&mut delay).expect("Initialization failed");
// 3. Only now is the .read_temp_and_hum() method available in your IDE!
let measurement = dht11.read_temp_and_hum(&mut delay);Β§π License
Distributed under the MIT License. See the LICENSE file for more information.