embassy/examples/rp/src/bin/pio_async.rs

//! This example shows powerful PIO module in the RP2040 chip.

#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]
use defmt::info;
use embassy_executor::Spawner;
use embassy_rp::bind_interrupts;
use embassy_rp::peripherals::PIO0;
use embassy_rp::pio::{Common, Config, InterruptHandler, Irq, Pio, PioPin, ShiftDirection, StateMachine};
use fixed::traits::ToFixed;
use fixed_macro::types::U56F8;
use {defmt_rtt as _, panic_probe as _};

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

fn setup_pio_task_sm0<'a>(pio: &mut Common<'a, PIO0>, sm: &mut StateMachine<'a, PIO0, 0>, pin: impl PioPin) {
    // Setup sm0

    // Send data serially to pin
    let prg = pio_proc::pio_asm!(
        ".origin 16",
        "set pindirs, 1",
        ".wrap_target",
        "out pins,1 [19]",
        ".wrap",
    );

    let mut cfg = Config::default();
    cfg.use_program(&pio.load_program(&prg.program), &[]);
    let out_pin = pio.make_pio_pin(pin);
    cfg.set_out_pins(&[&out_pin]);
    cfg.set_set_pins(&[&out_pin]);
    cfg.clock_divider = (U56F8!(125_000_000) / 20 / 200).to_fixed();
    cfg.shift_out.auto_fill = true;
    sm.set_config(&cfg);
}

#[embassy_executor::task]
async fn pio_task_sm0(mut sm: StateMachine<'static, PIO0, 0>) {
    sm.set_enable(true);

    let mut v = 0x0f0caffa;
    loop {
        sm.tx().wait_push(v).await;
        v ^= 0xffff;
        info!("Pushed {:032b} to FIFO", v);
    }
}

fn setup_pio_task_sm1<'a>(pio: &mut Common<'a, PIO0>, sm: &mut StateMachine<'a, PIO0, 1>) {
    // Setupm sm1

    // Read 0b10101 repeatedly until ISR is full
    let prg = pio_proc::pio_asm!(
        //
        ".origin 8",
        "set x, 0x15",
        ".wrap_target",
        "in x, 5 [31]",
        ".wrap",
    );

    let mut cfg = Config::default();
    cfg.use_program(&pio.load_program(&prg.program), &[]);
    cfg.clock_divider = (U56F8!(125_000_000) / 2000).to_fixed();
    cfg.shift_in.auto_fill = true;
    cfg.shift_in.direction = ShiftDirection::Right;
    sm.set_config(&cfg);
}

#[embassy_executor::task]
async fn pio_task_sm1(mut sm: StateMachine<'static, PIO0, 1>) {
    sm.set_enable(true);
    loop {
        let rx = sm.rx().wait_pull().await;
        info!("Pulled {:032b} from FIFO", rx);
    }
}

fn setup_pio_task_sm2<'a>(pio: &mut Common<'a, PIO0>, sm: &mut StateMachine<'a, PIO0, 2>) {
    // Setup sm2

    // Repeatedly trigger IRQ 3
    let prg = pio_proc::pio_asm!(
        ".origin 0",
        ".wrap_target",
        "set x,10",
        "delay:",
        "jmp x-- delay [15]",
        "irq 3 [15]",
        ".wrap",
    );
    let mut cfg = Config::default();
    cfg.use_program(&pio.load_program(&prg.program), &[]);
    cfg.clock_divider = (U56F8!(125_000_000) / 2000).to_fixed();
    sm.set_config(&cfg);
}

#[embassy_executor::task]
async fn pio_task_sm2(mut irq: Irq<'static, PIO0, 3>, mut sm: StateMachine<'static, PIO0, 2>) {
    sm.set_enable(true);
    loop {
        irq.wait().await;
        info!("IRQ trigged");
    }
}

#[embassy_executor::main]
async fn main(spawner: Spawner) {
    let p = embassy_rp::init(Default::default());
    let pio = p.PIO0;

    let Pio {
        mut common,
        irq3,
        mut sm0,
        mut sm1,
        mut sm2,
        ..
    } = Pio::new(pio, Irqs);

    setup_pio_task_sm0(&mut common, &mut sm0, p.PIN_0);
    setup_pio_task_sm1(&mut common, &mut sm1);
    setup_pio_task_sm2(&mut common, &mut sm2);
    spawner.spawn(pio_task_sm0(sm0)).unwrap();
    spawner.spawn(pio_task_sm1(sm1)).unwrap();
    spawner.spawn(pio_task_sm2(irq3, sm2)).unwrap();
}