esp-hal/esp32s2-hal/examples/embassy_multiprio.rs
2023-10-12 10:15:35 -07:00

114 lines
3.4 KiB
Rust

//! This example shows how to use the interrupt executors to prioritize some
//! tasks over others. The low priority task will not be able to run its async
//! task while the blocking task is running, but the high priority task will be
//! able to blink the LED regardless.
#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]
use embassy_time::{Duration, Instant, Ticker};
use esp32s2_hal::{
clock::ClockControl,
embassy::{
self,
executor::{FromCpu1, FromCpu2, InterruptExecutor},
},
gpio::{GpioPin, Output, PushPull, IO},
interrupt::Priority,
peripherals::Peripherals,
prelude::*,
};
use esp_backtrace as _;
use esp_hal_common::get_core;
use esp_println::println;
use static_cell::make_static;
static INT_EXECUTOR_0: InterruptExecutor<FromCpu1> = InterruptExecutor::new();
static INT_EXECUTOR_1: InterruptExecutor<FromCpu2> = InterruptExecutor::new();
#[interrupt]
fn FROM_CPU_INTR1() {
unsafe { INT_EXECUTOR_0.on_interrupt() }
}
#[interrupt]
fn FROM_CPU_INTR2() {
unsafe { INT_EXECUTOR_1.on_interrupt() }
}
/// Periodically turns the LED on and off.
#[embassy_executor::task]
async fn high_prio(led: &'static mut GpioPin<Output<PushPull>, 0>) {
println!("Starting high_prio() on core {}", get_core() as usize);
let mut ticker = Ticker::every(Duration::from_secs(1));
loop {
esp_println::println!("LED on");
led.set_low().unwrap();
ticker.next().await;
esp_println::println!("LED off");
led.set_high().unwrap();
ticker.next().await;
}
}
/// Simulates some blocking (badly behaving) task.
#[embassy_executor::task]
async fn low_prio_blocking() {
println!(
"Starting low_prio_blocking() on core {}",
get_core() as usize
);
let start = Instant::now();
while start.elapsed() < Duration::from_secs(10) {}
esp_println::println!("Low prio task finished");
}
/// Simulates a well-behaved async task that prints to the serial output.
#[embassy_executor::task]
async fn low_prio_async() {
println!("Starting low_prio_async() on core {}", get_core() as usize);
let mut ticker = Ticker::every(Duration::from_secs(1));
loop {
// Note that when the blocking task finishes, the ticker will fire multiple
// times.
println!("Tick from low priority async task");
ticker.next().await;
}
}
#[entry]
fn main() -> ! {
let peripherals = Peripherals::take();
let system = peripherals.SYSTEM.split();
let clocks = ClockControl::boot_defaults(system.clock_control).freeze();
// Set GPIO2 as an output, and set its state high initially.
let io = IO::new(peripherals.GPIO, peripherals.IO_MUX);
#[cfg(feature = "embassy-time-systick")]
embassy::init(
&clocks,
esp32s2_hal::systimer::SystemTimer::new(peripherals.SYSTIMER),
);
#[cfg(feature = "embassy-time-timg0")]
{
let timer_group0 = esp32s2_hal::timer::TimerGroup::new(peripherals.TIMG0, &clocks);
embassy::init(&clocks, timer_group0.timer0);
}
let led = make_static!(io.pins.gpio0.into_push_pull_output());
let spawner = INT_EXECUTOR_0.start(Priority::Priority2);
spawner.spawn(high_prio(led)).ok();
let spawner = INT_EXECUTOR_1.start(Priority::Priority1);
spawner.spawn(low_prio_async()).ok();
spawner.spawn(low_prio_blocking()).ok();
// Just loop to show that the main thread does not need to poll the executor.
loop {}
}