Don't use embedded_dma in nrf uarte.

embassy-nrf-examples/src/bin/uart.rs

@@ -28,6 +28,7 @@ async fn run(mut uart: uarte::Uarte<pac::UARTE0>) {
     info!("wrote hello in uart!");
 
     loop {
+        let buf_len = buf.len();
         info!("reading...");
 
         // `receive()` doesn't return until the buffer has been completely filled with
@@ -37,19 +38,17 @@ async fn run(mut uart: uarte::Uarte<pac::UARTE0>) {
         // 1 second timer, effectively adding a timeout to the receive operation.
         let recv_fut = uart.receive(&mut buf);
         let timer_fut = Timer::after(Duration::from_millis(1000));
-        let received = match select(recv_fut, timer_fut).await {
+        let received_len = match select(recv_fut, timer_fut).await {
             // recv_fut completed first, so we've received `buf_len` bytes.
-            Either::Left((buf, _)) => buf,
+            Either::Left(_) => buf_len,
             // timer_fut completed first. `select` gives us back the future that didn't complete, which
             // is `recv_fut` in this case, so we can do further stuff with it.
             //
             // The recv_fut would stop the uart read automatically when dropped. However, we want to know how
             // many bytes have been received, so we have to "gracefully stop" it with `.stop()`.
-            Either::Right((_, recv_fut)) => {
-                let (buf, n) = recv_fut.stop().await;
-                &buf[..n]
-            }
+            Either::Right((_, recv_fut)) => recv_fut.stop().await,
         };
+        let received = &mut buf[..received_len];
 
         if received.len() > 0 {
             info!("read done, got {:[u8]}", received);