DHT11 Driver for ESP32

A no_std Rust driver for the DHT11 temperature and humidity sensor designed for ESP32 microcontrollers.

Features

• No Standard Library - Fully compatible with embedded environments
• ESP32 HAL Integration - Built with esp-hal (v1.0.0-rc.1)
• Minimal Dependencies - Lightweight and efficient
• Temperature & Humidity Readings - Returns both values in a single read
• Error Handling - Comprehensive error types for reliability

Installation

Add to your Cargo.toml:

[dependencies]
esp32_hal_dht11_driver = "0.2.1"

Usage

Basic Example

use esp32_hal_dht11_driver::DHT11;
use esp_hal::delay::Delay;
use esp_hal::gpio::Flex;

fn main() {
    let delay = Delay::new();
    let mut dht11 = DHT11::new(delay);
    
    // Configure your GPIO pin as a Flex GPIO
    let mut pin = Flex::new(io.gpio2);
    
    loop {
        match dht11.read(&mut pin) {
            Ok(reading) => {
                println!("Temperature: {}°C", reading.temperature);
                println!("Humidity: {}%", reading.humidity);
            }
            Err(error) => {
                eprintln!("Sensor error: {:?}", error);
            }
        }
        
        delay.delay_millis(2000);
    }
}

API

DHT11::new(delay: Delay) -> Self

Creates a new DHT11 instance with a delay provider.

DHT11::read(&mut self, pin: &mut esp_hal::gpio::Flex) -> Result<Reading, SensorError>

Reads temperature and humidity data from the sensor.

Returns:

• Ok(Reading) - Contains temperature (i8) in °C and humidity (u8) in %
• Err(SensorError) - One of: Timeout, ChecksumMismatch, or PinError

Supported Platforms

• ESP32 (and variants: ESP32-S3, ESP32-C3, etc.)
• Any ESP32 with GPIO support

Error Handling

The driver may return the following errors:

• SensorError::Timeout - Communication timeout with sensor
• SensorError::ChecksumMismatch - Data integrity check failed
• SensorError::PinError - GPIO operation failed

Implement proper error handling in your application for robust operation.

Technical Details

• Sensor Protocol - DHT11 digital communication protocol (1-wire)
• Temperature Range - -20 to +60°C
• Humidity Range - 20% to 95% RH
• Read Interval - Minimum 2 seconds between consecutive reads

Origin

This library is forked from esp32-dht11-rs and updated to:

• Remove dependency on the embedded_hal crate
• Resolve compatibility issues with various ESP32 HAL crates
• Support esp-hal v1.0.0-rc.1

License

MIT License

Hardware