Crate dht_sensor

DHT11/DHT22 sensor driver

This library provides a platform-agnostic driver for the DHT11 and DHT22 sensors.

Use one of two functions dht11::Reading::read and dht22::Reading::read to get a reading.

Usage

The only prerequisites are an embedded-hal implementation that provides:

• Delay-implementing type, for example Cortex-M microcontrollers typically use the SysTick.
• InputOutputPin-implementing type, for example an Output<OpenDrain> from stm32f0xx_hal.

Example

See the stm32f042 example for a working example of how to use the library.

#![no_std]
#![no_main]

use crate::hal::{delay, gpio, prelude::*, stm32};
use cortex_m_rt::entry;
use cortex_m_semihosting::hprintln;
use panic_halt as _;
use stm32f0xx_hal as hal;

use dht_sensor::*;

#[entry]
fn main() -> ! {
    let mut p = stm32::Peripherals::take().unwrap();
    let cp = stm32::CorePeripherals::take().unwrap();
    let mut rcc = p.RCC.configure().sysclk(8.mhz()).freeze(&mut p.FLASH);

    // This is used by `dht-sensor` to wait for signals
    let mut delay = delay::Delay::new(cp.SYST, &rcc);

    // This could be any `gpio` port
    let gpio::gpioa::Parts { pa1, .. } = p.GPIOA.split(&mut rcc);

    // The DHT11 datasheet suggests 1 second
    hprintln!("Waiting on the sensor...").unwrap();
    delay.delay_ms(1000_u16);

    // An `Output<OpenDrain>` is both `InputPin` and `OutputPin`
    let mut pa1 = cortex_m::interrupt::free(|cs| pa1.into_open_drain_output(cs));

    match dht11::Reading::read(&mut delay, &mut pa1) {
        Ok(dht11::Reading {
            temperature,
            relative_humidity,
        }) => hprintln!("{}°, {}% RH", temperature, relative_humidity).unwrap(),
        Err(e) => hprintln!("Error {:?}", e).unwrap(),
    }
    hprintln!("Looping forever now, thanks!").unwrap();

    loop {}
}

Modules

dht11
dht22

Enums

DhtError

Traits

Delay
DhtReading
InputOutputPin