embassy/examples/nrf/src/bin/mpsc.rs
Dario Nieuwenhuis 22bc1e4ae1 nrf/gpio: add infallible inherent methods, remove some duplication.
This implements Input and Output using FlexPin, to avoid some code duplication.
2021-12-20 00:55:18 +01:00

61 lines
1.9 KiB
Rust

#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]
#[path = "../example_common.rs"]
mod example_common;
use defmt::unwrap;
use embassy::blocking_mutex::kind::Noop;
use embassy::channel::mpsc::{self, Channel, Sender, TryRecvError};
use embassy::executor::Spawner;
use embassy::time::{Duration, Timer};
use embassy::util::Forever;
use embassy_nrf::gpio::{Level, Output, OutputDrive};
use embassy_nrf::Peripherals;
enum LedState {
On,
Off,
}
static CHANNEL: Forever<Channel<Noop, LedState, 1>> = Forever::new();
#[embassy::task(pool_size = 1)]
async fn my_task(sender: Sender<'static, Noop, LedState, 1>) {
loop {
let _ = sender.send(LedState::On).await;
Timer::after(Duration::from_secs(1)).await;
let _ = sender.send(LedState::Off).await;
Timer::after(Duration::from_secs(1)).await;
}
}
#[embassy::main]
async fn main(spawner: Spawner, p: Peripherals) {
let mut led = Output::new(p.P0_13, Level::Low, OutputDrive::Standard);
let channel = CHANNEL.put(Channel::new());
let (sender, mut receiver) = mpsc::split(channel);
unwrap!(spawner.spawn(my_task(sender)));
// We could just loop on `receiver.recv()` for simplicity. The code below
// is optimized to drain the queue as fast as possible in the spirit of
// handling events as fast as possible. This optimization is benign when in
// thread mode, but can be useful when interrupts are sending messages
// with the channel having been created via with_critical_sections.
loop {
let maybe_message = match receiver.try_recv() {
m @ Ok(..) => m.ok(),
Err(TryRecvError::Empty) => receiver.recv().await,
Err(TryRecvError::Closed) => break,
};
match maybe_message {
Some(LedState::On) => led.set_high(),
Some(LedState::Off) => led.set_low(),
_ => (),
}
}
}