read a dht11 humidity sensor with a discovery f3

main.rs

#![no_std]
#![no_main]

use crate::hal::{delay, gpio, prelude::*, stm32};
use cortex_m;
use cortex_m_rt::entry;
use cortex_m_semihosting::hprintln;
use panic_halt as _;
use stm32f3xx_hal as hal;
use stm32f3xx_hal::rcc::RccExt;

use dht_sensor::*;

#[entry]
fn main() -> ! {
    let mut dp = stm32::Peripherals::take().unwrap();
    let cp = stm32::CorePeripherals::take().unwrap();
    let mut rcc = dp.RCC.constrain();
    let mut flash = dp.FLASH.constrain();
    let clocks = rcc.cfgr.freeze(&mut flash.acr);

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

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

    // 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(??? , ???));

    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 {}
}