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Crate thread_delay

Crate thread_delay 

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This crate provides a blocking implementation of DelayNs from embedded_hal that can be used on Linux systems using the Linux standard library. It is intended to be a drop-in replacement for application using libraries that were written for embedded devices but have access to the standard library, such as a single board computer (SBC) running Linux.

The Delay implementation is like the one from [linux_embedded_hal] but provides all the delay_* functions defined by the trait.

The functions are:

  1. delay_ns for nanosecond delays
  2. delay_us for microsecond delays
  3. delay_ms for milliseconds delays

§Example

This example is an application running on a Raspberry Pi Zero 2 W that takes readings from a bme280 atmospheric sensor.

use thread_delay::Delay;

use bme280::i2c::BME280;
use rppal::i2c::I2c;
use std::time::Instant;
  
enum LoopState {
    Waiting,
    Measureing,
}

fn main() -> ! {
    let i2c = I2c::with_bus(1).expect("failed to find i2c bus 1");
    assert!(i2c.bus() == 1_u8);

    let mut delay = Delay {};

    let mut bme280 = BME280::new_primary(i2c);

    bme280.init(&mut delay).expect("failed to initialize bme280 sensor");

    let mut state = LoopState::Waiting;

    let delay_millis: u128 = 1_000;

    let mut last_update = Instant::now();

    loop {
        let elapsed = last_update.elapsed();

        match state {
            LoopState::Waiting => {
                if elapsed.as_millis() >= delay_millis {
                    state = LoopState::Measureing
                }
            }

            LoopState::Measureing => {
                let measurements = bme280
                    .measure(&mut delay)
                    .expect("failed to read measurements from bme280");

                println!("Temp:     |{:-10.3} C |", measurements.temperature);
                println!("Humidity: |{:-10.3} % |", measurements.humidity);
                println!("Pressure: |{:-10.3} Pa|", measurements.pressure);
                println!("-----");

                last_update = Instant::now();
                state = LoopState::Waiting;
            }
        }
    }
}

Structs§

ThreadDelay
Empty struct that implements the DelayNs trait using std::thread::sleep

Type Aliases§

Delay
A convienvce alias for keeping the Delay struct name