examples/rp235x/src/bin/pio_pwm.rs


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//! This example shows how to create a pwm using the PIO module in the RP235x chip.

#![no_std]
#![no_main]
use core::time::Duration;

use embassy_executor::Spawner;
use embassy_rp::bind_interrupts;
use embassy_rp::peripherals::PIO0;
use embassy_rp::pio::{InterruptHandler, Pio};
use embassy_rp::pio_programs::pwm::{PioPwm, PioPwmProgram};
use embassy_time::Timer;
use {defmt_rtt as _, panic_probe as _};

const REFRESH_INTERVAL: u64 = 20000;

bind_interrupts!(struct Irqs {
    PIO0_IRQ_0 => InterruptHandler<PIO0>;
});

#[embassy_executor::main]
async fn main(_spawner: Spawner) {
    let p = embassy_rp::init(Default::default());
    let Pio { mut common, sm0, .. } = Pio::new(p.PIO0, Irqs);

    // Note that PIN_25 is the led pin on the Pico
    let prg = PioPwmProgram::new(&mut common);
    let mut pwm_pio = PioPwm::new(&mut common, sm0, p.PIN_25, &prg);
    pwm_pio.set_period(Duration::from_micros(REFRESH_INTERVAL));
    pwm_pio.start();

    let mut duration = 0;
    loop {
        duration = (duration + 1) % 1000;
        pwm_pio.write(Duration::from_micros(duration));
        Timer::after_millis(1).await;
    }
}