working async buffered uart

usart_async_dma/src/bin/main.rs

@@ -0,0 +1,49 @@
+// src/bin/main.rs
+#![no_std]
+#![no_main]
+
+use defmt::*;
+use embassy_executor::Spawner;
+use embassy_time::{Duration, Timer};
+use embassy_stm32::usart::{Config, Uart};
+use embassy_stm32::bind_interrupts;
+use embassy_stm32::mode::Async;
+use {defmt_rtt as _, panic_probe as _};
+
+bind_interrupts!(
+    struct Irqs {
+        USART1 => embassy_stm32::usart::InterruptHandler<embassy_stm32::peripherals::USART1>;
+    }
+);
+
+#[embassy_executor::task]
+async fn receive_uart(mut uart: Uart<'static, Async>) {
+    let mut buf = [0u8; 1];
+    loop {
+        unwrap!(uart.read(&mut buf).await);
+        unwrap!(uart.write(&buf).await);
+        unwrap!(uart.write(b"a\r\n").await);
+        info!("uart received {}", buf[0]);
+    }
+}
+
+#[embassy_executor::main]
+async fn main(spawner: Spawner) {
+    info!("tititititi");
+    let p = embassy_stm32::init(Default::default());
+
+    let config = Config::default();
+    let usart = Uart::new(p.USART1, p.PA10, p.PA9, Irqs, p.GPDMA1_CH1, p.GPDMA1_CH0, config).unwrap();
+
+    info!("starting echo");
+    spawner.spawn(receive_uart(usart)).unwrap();
+
+    let mut counter: u8 = 230;
+    loop {
+        counter = counter.wrapping_add(1);
+        info!("CPU doing other work: {}", counter);
+        Timer::after(Duration::from_millis(300)).await;
+
+    }
+
+}

usart_async_dma/src/lib.rs

@@ -0,0 +1 @@
+#![no_std]