embassy/examples/stm32f4/src/bin/usart_dma.rs

#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]

use core::fmt::Write;
use defmt::*;
use defmt_rtt as _; // global logger
use embassy::executor::Spawner;
use embassy_stm32::dma::NoDma;
use embassy_stm32::usart::{Config, Uart};
use embassy_stm32::Peripherals;
use heapless::String;
use panic_probe as _;

#[embassy::main]
async fn main(_spawner: Spawner, p: Peripherals) {
    info!("Hello World!");

    let config = Config::default();
    let mut usart = Uart::new(p.USART3, p.PD9, p.PD8, p.DMA1_CH3, NoDma, config);

    for n in 0u32.. {
        let mut s: String<128> = String::new();
        core::write!(&mut s, "Hello DMA World {}!\r\n", n).unwrap();

        unwrap!(usart.write(s.as_bytes()).await);
        info!("wrote DMA");
    }
}