buffered generalized working

usart_async_buffered/src/bin/main.rs

@@ -0,0 +1,67 @@
+// 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::usart::{BufferedUart, BufferedInterruptHandler};
+use embassy_stm32::mode::Async;
+use embedded_io_async::{Read, Write};
+use embassy_stm32::peripherals;
+use static_cell::StaticCell;
+use {defmt_rtt as _, panic_probe as _};
+
+bind_interrupts!(
+    struct Irqs {
+        USART1 => BufferedInterruptHandler<peripherals::USART1>;
+    }
+);
+
+#[embassy_executor::task]
+async fn receive_uart(mut uart: BufferedUart<'static>) {
+    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());
+
+    static TX_BUF: StaticCell<[u8; 256]> = StaticCell::new();
+    static RX_BUF: StaticCell<[u8; 256]> = StaticCell::new();
+    let tx_buf = TX_BUF.init([0; 256]);
+    let rx_buf = RX_BUF.init([0; 256]);
+
+    let mut cfg = Config::default();
+    cfg.baudrate = 230_400;
+
+    let config = Config::default();
+    let usart = BufferedUart::new(
+        p.USART1,
+        p.PA10, // RX
+        p.PA9,  // TX
+        tx_buf,
+        rx_buf,
+        Irqs,
+        cfg,
+    ).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_buffered_generalized/.cargo/config.toml

@@ -0,0 +1,15 @@
+[build]
+target = "thumbv8m.main-none-eabihf"
+
+[target.thumbv8m.main-none-eabihf]
+runner = "probe-rs run --chip STM32U575ZITxQ"
+
+rustflags = [
+  "-C", "linker=rust-lld",
+  "-C", "link-arg=-Tlink.x",
+  "-C", "link-arg=-Tdefmt.x",
+  "-C", "link-arg=--nmagic",
+]
+
+[package.metadata.cargo-flash]
+chip = "STM32U575ZIT"

usart_async_buffered_generalized/.gitignore

@@ -0,0 +1 @@
+/target

usart_async_buffered_generalized/Cargo.toml

@@ -0,0 +1,30 @@
+[package]
+authors = ["Priec <filippriec@gmail.com>"]
+name = "hal_rng"
+edition = "2024"
+version = "0.1.0"
+
+
+[dependencies]
+cortex-m = { version = "0.7.7", features = ["inline-asm", "critical-section-single-core"] }
+cortex-m-rt = "0.7.5"
+panic-halt = "1.0.0"
+
+embassy-executor = { version = "0.9.1", features = ["arch-cortex-m", "executor-thread"] }
+embassy-futures = "0.1.2"
+embassy-stm32 = { version = "0.4.0", features = ["unstable-pac", "stm32u575zi", "time-driver-any", "memory-x", "defmt"] }
+embassy-sync = "0.7.2"
+embassy-time = { version = "0.5.0", features = ["tick-hz-32_768"] }
+embassy-usb = "0.5.1"
+
+embedded-hal = "1.0.0"
+embedded-graphics = "0.8.1"
+heapless = { version = "0.9.1", default-features = false }
+micromath = "2.1.0"
+tinybmp = "0.6.0"
+panic-probe = { version = "1.0.0", features = ["defmt"] }
+defmt-rtt = "1.1.0"
+defmt = "1.0.1"
+static_cell = "2.1.1"
+embedded-io-async = "0.6.0"
+embedded-io = "0.6.1"

usart_async_buffered_generalized/LICENSE-APACHE

@@ -0,0 +1,201 @@
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usart_async_buffered_generalized/LICENSE-MIT

@@ -0,0 +1,23 @@
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
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+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.

usart_async_buffered_generalized/Makefile

@@ -0,0 +1,23 @@
+TARGET = thumbv8m.main-none-eabihf
+CHIP = STM32U575ZI
+BIN = stm32u5-blinky
+MODE ?= release
+TARGET_DIR = target/$(TARGET)/$(MODE)
+ELF = $(TARGET_DIR)/$(BIN)
+PROBE = probe-rs
+
+.PHONY: all build flash clean empty
+
+all: build
+
+build:
+	cargo build --$(MODE)
+
+flash: build
+	$(PROBE) run --chip $(CHIP) $(ELF)
+
+empty:
+	$(PROBE) erase --chip $(CHIP)
+
+clean:
+	cargo clean

usart_async_buffered_generalized/README.md

@@ -0,0 +1,232 @@
+# `app-template`
+
+> Quickly set up a [`probe-rs`] + [`defmt`] + [`flip-link`] embedded project
+
+[`probe-rs`]: https://crates.io/crates/probe-rs
+[`defmt`]: https://github.com/knurling-rs/defmt
+[`flip-link`]: https://github.com/knurling-rs/flip-link
+
+## Dependencies
+
+### 1. `flip-link`:
+
+```bash
+cargo install flip-link
+```
+
+### 2. `probe-rs`:
+
+Install probe-rs by following the instructions at <https://probe.rs/docs/getting-started/installation/>.
+
+### 3. [`cargo-generate`]:
+
+```bash
+cargo install cargo-generate
+```
+
+[`cargo-generate`]: https://crates.io/crates/cargo-generate
+
+> *Note:* You can also just clone this repository instead of using `cargo-generate`, but this involves additional manual adjustments.
+
+## Setup
+
+### 1. Initialize the project template
+
+```bash
+cargo generate \
+    --git https://github.com/knurling-rs/app-template \
+    --branch main \
+    --name my-app
+```
+
+If you look into your new `my-app` folder, you'll find that there are a few `TODO`s in the files marking the properties you need to set.
+
+Let's walk through them together now.
+
+### 2. Set `probe-rs` chip
+
+Pick a chip from ` probe-rs chip list` and enter it into `.cargo/config.toml`.
+
+If, for example, you have a nRF52840 Development Kit as used in one of [our exercises], replace `{{chip}}` with `nRF52840_xxAA`.
+
+[our workshops]: https://rust-exercises.ferrous-systems.com
+
+```diff
+ # .cargo/config.toml
+-runner = ["probe-rs", "run", "--chip", "$CHIP", "--log-format=oneline"]
++runner = ["probe-rs", "run", "--chip", "nRF52840_xxAA", "--log-format=oneline"]
+```
+
+### 3. Adjust the compilation target
+
+In `.cargo/config.toml`, pick the right compilation target for your board.
+
+```diff
+ # .cargo/config.toml
+ [build]
+-target = "thumbv6m-none-eabi"    # Cortex-M0 and Cortex-M0+
+-# target = "thumbv7m-none-eabi"    # Cortex-M3
+-# target = "thumbv7em-none-eabi"   # Cortex-M4 and Cortex-M7 (no FPU)
+-# target = "thumbv7em-none-eabihf" # Cortex-M4F and Cortex-M7F (with FPU)
++target = "thumbv7em-none-eabihf" # Cortex-M4F (with FPU)
+```
+
+Add the target with `rustup`.
+
+```bash
+rustup target add thumbv7em-none-eabihf
+```
+
+### 4. Add a HAL as a dependency
+
+In `Cargo.toml`, list the Hardware Abstraction Layer (HAL) for your board as a dependency.
+
+For the nRF52840 you'll want to use the [`nrf52840-hal`].
+
+[`nrf52840-hal`]: https://crates.io/crates/nrf52840-hal
+
+```diff
+ # Cargo.toml
+ [dependencies]
+-# some-hal = "1.2.3"
++nrf52840-hal = "0.14.0"
+```
+
+⚠️ Note for RP2040 users ⚠️
+
+You will need to not just specify the `rp-hal` HAL, but a BSP (board support crate) which includes a second stage bootloader. Please find a list of available BSPs [here](https://github.com/rp-rs/rp-hal-boards#packages).
+
+### 5. Import your HAL
+
+Now that you have selected a HAL, fix the HAL import in `src/lib.rs`
+
+```diff
+ // my-app/src/lib.rs
+-// use some_hal as _; // memory layout
++use nrf52840_hal as _; // memory layout
+```
+
+### (6. Get a linker script)
+
+Some HAL crates require that you manually copy over a file called `memory.x` from the HAL to the root of your project. For nrf52840-hal, this is done automatically so no action is needed. For other HAL crates, see their documentation on where to find an example file.
+
+The `memory.x` file should look something like:
+
+```text
+MEMORY
+{
+  FLASH : ORIGIN = 0x00000000, LENGTH = 1024K
+  RAM   : ORIGIN = 0x20000000, LENGTH = 256K
+}
+```
+
+The `memory.x` file is included in the `cortex-m-rt` linker script `link.x`, and so `link.x` is the one you should tell `rustc` to use (see the `.cargo/config.toml` file where we do that).
+
+### 7. Run!
+
+You are now all set to `cargo-run` your first `defmt`-powered application!
+There are some examples in the `src/bin` directory.
+
+Start by `cargo run`-ning `my-app/src/bin/hello.rs`:
+
+```console
+$ # `rb` is an alias for `run --bin`
+$ cargo rb hello
+    Finished `dev` profile [optimized + debuginfo] target(s) in 0.01s
+     Running `probe-rs run --chip nrf52840_xxaa --log-format=oneline target/thumbv6m-none-eabi/debug/hello`
+      Erasing ✔ 100% [####################]   8.00 KiB @  15.79 KiB/s (took 1s)
+  Programming ✔ 100% [####################]   8.00 KiB @  13.19 KiB/s (took 1s)                                                                                                                        Finished in 1.11s
+Hello, world!
+
+$ echo $?
+0
+```
+
+If you're running out of memory (`flip-link` bails with an overflow error), you can decrease the size of the device memory buffer by setting the `DEFMT_RTT_BUFFER_SIZE` environment variable. The default value is 1024 bytes, and powers of two should be used for optimal performance:
+
+```console
+$ DEFMT_RTT_BUFFER_SIZE=64 cargo rb hello
+```
+
+### (8. Set `rust-analyzer.linkedProjects`)
+
+If you are using [rust-analyzer] with VS Code for IDE-like features you can add following configuration to your `.vscode/settings.json` to make it work transparently across workspaces. Find the details of this option in the [RA docs].
+
+```json
+{
+    "rust-analyzer.linkedProjects": [
+        "Cargo.toml",
+        "firmware/Cargo.toml",
+    ]
+}
+```
+
+[RA docs]: https://rust-analyzer.github.io/manual.html#configuration
+[rust-analyzer]: https://rust-analyzer.github.io/
+
+## Running tests
+
+The template comes configured for running unit tests and integration tests on the target.
+
+Unit tests reside in the library crate and can test private API; the initial set of unit tests are in `src/lib.rs`.
+`cargo test --lib` will run those unit tests.
+
+```console
+$ cargo test --lib
+   Compiling example v0.1.0 (./knurling-rs/example)
+    Finished `test` profile [optimized + debuginfo] target(s) in 0.15s
+     Running unittests src/lib.rs (target/thumbv6m-none-eabi/debug/deps/example-2b0d0e25d141bf57)
+      Erasing ✔ 100% [####################]   8.00 KiB @  15.99 KiB/s (took 1s)
+  Programming ✔ 100% [####################]   8.00 KiB @  13.33 KiB/s (took 1s)                                                                                                                        Finished in 1.10s
+(1/1) running `it_works`...
+all tests passed!
+```
+
+Integration tests reside in the `tests` directory; the initial set of integration tests are in `tests/integration.rs`.
+`cargo test --test integration` will run those integration tests.
+Note that the argument of the `--test` flag must match the name of the test file in the `tests` directory.
+
+```console
+$ cargo test --test integration
+   Compiling example v0.1.0 (./knurling-rs/example)
+    Finished `test` profile [optimized + debuginfo] target(s) in 0.10s
+     Running tests/integration.rs (target/thumbv6m-none-eabi/debug/deps/integration-aaaff41151f6a722)
+      Erasing ✔ 100% [####################]   8.00 KiB @  16.03 KiB/s (took 0s)
+  Programming ✔ 100% [####################]   8.00 KiB @  13.19 KiB/s (took 1s)                                                                                                                        Finished in 1.11s
+(1/1) running `it_works`...
+all tests passed!
+```
+
+Note that to add a new test file to the `tests` directory you also need to add a new `[[test]]` section to `Cargo.toml`.
+
+To run all the tests via `cargo test` the tests need to be explicitly disabled for all the existing binary targets.
+See `Cargo.toml` for details on how to do this.
+
+## Support
+
+`app-template` is part of the [Knurling] project, [Ferrous Systems]' effort at
+improving tooling used to develop for embedded systems.
+
+If you think that our work is useful, consider sponsoring it via [GitHub
+Sponsors].
+
+## License
+
+Licensed under either of
+
+- Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or
+  http://www.apache.org/licenses/LICENSE-2.0)
+
+- MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
+
+at your option.
+
+### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally submitted
+for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
+licensed as above, without any additional terms or conditions.
+
+[Knurling]: https://knurling.ferrous-systems.com
+[Ferrous Systems]: https://ferrous-systems.com/
+[GitHub Sponsors]: https://github.com/sponsors/knurling-rs

usart_async_buffered_generalized/src/bin/main.rs

@@ -0,0 +1,105 @@
+// src/bin/main.rs
+#![no_std]
+#![no_main]
+
+use defmt::*;
+use embassy_executor::Spawner;
+use embassy_time::{Duration, Timer};
+use embassy_stm32::bind_interrupts;
+use embassy_stm32::peripherals;
+use embassy_stm32::usart::{BufferedInterruptHandler, BufferedUart, Config};
+use embedded_io_async::{Read, Write};
+use static_cell::StaticCell;
+use {defmt_rtt as _, panic_probe as _};
+
+// Select + channel + heapless Vec
+use embassy_futures::select::{select, Either};
+use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
+use embassy_sync::channel::Channel;
+use heapless::Vec;
+
+const MAX_MSG: usize = 64;
+const QSIZE: usize = 4;
+static UART_TX: Channel<CriticalSectionRawMutex, Vec<u8, MAX_MSG>, QSIZE> = Channel::new();
+
+bind_interrupts!(
+    struct Irqs {
+        USART1 => BufferedInterruptHandler<peripherals::USART1>;
+    }
+);
+
+#[embassy_executor::task]
+async fn uart_task(mut uart: BufferedUart<'static>) {
+    let mut buf = [0u8; 1];
+
+    loop {
+        let rx_fut = uart.read(&mut buf);
+        let tx_fut = UART_TX.receive();
+
+        match select(rx_fut, tx_fut).await {
+            // Incoming RX byte
+            Either::First(res) => {
+                if let Ok(_) = res {
+                    // Echo and log
+                    unwrap!(uart.write(&buf).await);
+                    unwrap!(uart.write(b"a\r\n").await);
+                    info!("uart received {}", buf[0]);
+                    unwrap!(uart.flush().await);
+                }
+            }
+            // Outgoing TX request from main
+            Either::Second(msg) => {
+                unwrap!(uart.write(&msg).await);
+                unwrap!(uart.flush().await);
+                info!("sent {} bytes", msg.len());
+            }
+        }
+    }
+}
+
+pub async fn send_uart(data: &[u8]) {
+    let mut v: Vec<u8, MAX_MSG> = Vec::new();
+    let _ = v.extend_from_slice(data); // truncate if too long
+    UART_TX.send(v).await;
+}
+
+#[embassy_executor::main]
+async fn main(spawner: Spawner) {
+    info!("tititititi");
+    let p = embassy_stm32::init(Default::default());
+
+    static TX_BUF: StaticCell<[u8; 256]> = StaticCell::new();
+    static RX_BUF: StaticCell<[u8; 256]> = StaticCell::new();
+    let tx_buf = TX_BUF.init([0; 256]);
+    let rx_buf = RX_BUF.init([0; 256]);
+
+    let mut cfg = Config::default();
+    cfg.baudrate = 230_400;
+
+    let usart = BufferedUart::new(
+        p.USART1,
+        p.PA10, // RX
+        p.PA9,  // TX
+        tx_buf,
+        rx_buf,
+        Irqs,
+        cfg,
+    )
+    .unwrap();
+
+    info!("starting uart task");
+    spawner.spawn(uart_task(usart)).unwrap();
+
+    let mut counter: u32 = 230;
+    loop {
+        counter = counter.wrapping_add(1);
+
+        if counter % 10000 == 0 {
+            info!("CPU doing other work: {}", counter);
+        }
+        if counter % 100000 == 0 {
+            // Send whenever you want; the UART task performs the actual write.
+            send_uart(b"Hello\r\n").await;
+        }
+    }
+}

usart_async_buffered_generalized/src/lib.rs

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

usart_async_buffered_generalized/tests/integration.rs

@@ -0,0 +1,16 @@
+#![no_std]
+#![no_main]
+
+use stm32u5_blinky as _; // memory layout + panic handler
+
+// See https://crates.io/crates/defmt-test/0.3.0 for more documentation (e.g. about the 'state'
+// feature)
+#[defmt_test::tests]
+mod tests {
+    use defmt::assert;
+
+    #[test]
+    fn it_works() {
+        assert!(true)
+    }
+}

usart_async_dma/.cargo/config.toml

@@ -0,0 +1,15 @@
+[build]
+target = "thumbv8m.main-none-eabihf"
+
+[target.thumbv8m.main-none-eabihf]
+runner = "probe-rs run --chip STM32U575ZITxQ"
+
+rustflags = [
+  "-C", "linker=rust-lld",
+  "-C", "link-arg=-Tlink.x",
+  "-C", "link-arg=-Tdefmt.x",
+  "-C", "link-arg=--nmagic",
+]
+
+[package.metadata.cargo-flash]
+chip = "STM32U575ZIT"

usart_async_dma/.gitignore

@@ -0,0 +1 @@
+/target

usart_async_dma/Cargo.toml

@@ -0,0 +1,30 @@
+[package]
+authors = ["Priec <filippriec@gmail.com>"]
+name = "hal_rng"
+edition = "2024"
+version = "0.1.0"
+
+
+[dependencies]
+cortex-m = { version = "0.7.7", features = ["inline-asm", "critical-section-single-core"] }
+cortex-m-rt = "0.7.5"
+panic-halt = "1.0.0"
+
+embassy-executor = { version = "0.9.1", features = ["arch-cortex-m", "executor-thread"] }
+embassy-futures = "0.1.2"
+embassy-stm32 = { version = "0.4.0", features = ["unstable-pac", "stm32u575zi", "time-driver-any", "memory-x", "defmt"] }
+embassy-sync = "0.7.2"
+embassy-time = { version = "0.5.0", features = ["tick-hz-32_768"] }
+embassy-usb = "0.5.1"
+
+embedded-hal = "1.0.0"
+embedded-graphics = "0.8.1"
+heapless = { version = "0.9.1", default-features = false }
+micromath = "2.1.0"
+tinybmp = "0.6.0"
+panic-probe = { version = "1.0.0", features = ["defmt"] }
+defmt-rtt = "1.1.0"
+defmt = "1.0.1"
+static_cell = "2.1.1"
+embedded-io-async = "0.6.0"
+embedded-io = "0.6.1"

usart_async_dma/LICENSE-APACHE

@@ -0,0 +1,201 @@
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+limitations under the License.

usart_async_dma/LICENSE-MIT

@@ -0,0 +1,23 @@
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
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+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.

usart_async_dma/Makefile

@@ -0,0 +1,23 @@
+TARGET = thumbv8m.main-none-eabihf
+CHIP = STM32U575ZI
+BIN = stm32u5-blinky
+MODE ?= release
+TARGET_DIR = target/$(TARGET)/$(MODE)
+ELF = $(TARGET_DIR)/$(BIN)
+PROBE = probe-rs
+
+.PHONY: all build flash clean empty
+
+all: build
+
+build:
+	cargo build --$(MODE)
+
+flash: build
+	$(PROBE) run --chip $(CHIP) $(ELF)
+
+empty:
+	$(PROBE) erase --chip $(CHIP)
+
+clean:
+	cargo clean

usart_async_dma/README.md

@@ -0,0 +1,232 @@
+# `app-template`
+
+> Quickly set up a [`probe-rs`] + [`defmt`] + [`flip-link`] embedded project
+
+[`probe-rs`]: https://crates.io/crates/probe-rs
+[`defmt`]: https://github.com/knurling-rs/defmt
+[`flip-link`]: https://github.com/knurling-rs/flip-link
+
+## Dependencies
+
+### 1. `flip-link`:
+
+```bash
+cargo install flip-link
+```
+
+### 2. `probe-rs`:
+
+Install probe-rs by following the instructions at <https://probe.rs/docs/getting-started/installation/>.
+
+### 3. [`cargo-generate`]:
+
+```bash
+cargo install cargo-generate
+```
+
+[`cargo-generate`]: https://crates.io/crates/cargo-generate
+
+> *Note:* You can also just clone this repository instead of using `cargo-generate`, but this involves additional manual adjustments.
+
+## Setup
+
+### 1. Initialize the project template
+
+```bash
+cargo generate \
+    --git https://github.com/knurling-rs/app-template \
+    --branch main \
+    --name my-app
+```
+
+If you look into your new `my-app` folder, you'll find that there are a few `TODO`s in the files marking the properties you need to set.
+
+Let's walk through them together now.
+
+### 2. Set `probe-rs` chip
+
+Pick a chip from ` probe-rs chip list` and enter it into `.cargo/config.toml`.
+
+If, for example, you have a nRF52840 Development Kit as used in one of [our exercises], replace `{{chip}}` with `nRF52840_xxAA`.
+
+[our workshops]: https://rust-exercises.ferrous-systems.com
+
+```diff
+ # .cargo/config.toml
+-runner = ["probe-rs", "run", "--chip", "$CHIP", "--log-format=oneline"]
++runner = ["probe-rs", "run", "--chip", "nRF52840_xxAA", "--log-format=oneline"]
+```
+
+### 3. Adjust the compilation target
+
+In `.cargo/config.toml`, pick the right compilation target for your board.
+
+```diff
+ # .cargo/config.toml
+ [build]
+-target = "thumbv6m-none-eabi"    # Cortex-M0 and Cortex-M0+
+-# target = "thumbv7m-none-eabi"    # Cortex-M3
+-# target = "thumbv7em-none-eabi"   # Cortex-M4 and Cortex-M7 (no FPU)
+-# target = "thumbv7em-none-eabihf" # Cortex-M4F and Cortex-M7F (with FPU)
++target = "thumbv7em-none-eabihf" # Cortex-M4F (with FPU)
+```
+
+Add the target with `rustup`.
+
+```bash
+rustup target add thumbv7em-none-eabihf
+```
+
+### 4. Add a HAL as a dependency
+
+In `Cargo.toml`, list the Hardware Abstraction Layer (HAL) for your board as a dependency.
+
+For the nRF52840 you'll want to use the [`nrf52840-hal`].
+
+[`nrf52840-hal`]: https://crates.io/crates/nrf52840-hal
+
+```diff
+ # Cargo.toml
+ [dependencies]
+-# some-hal = "1.2.3"
++nrf52840-hal = "0.14.0"
+```
+
+⚠️ Note for RP2040 users ⚠️
+
+You will need to not just specify the `rp-hal` HAL, but a BSP (board support crate) which includes a second stage bootloader. Please find a list of available BSPs [here](https://github.com/rp-rs/rp-hal-boards#packages).
+
+### 5. Import your HAL
+
+Now that you have selected a HAL, fix the HAL import in `src/lib.rs`
+
+```diff
+ // my-app/src/lib.rs
+-// use some_hal as _; // memory layout
++use nrf52840_hal as _; // memory layout
+```
+
+### (6. Get a linker script)
+
+Some HAL crates require that you manually copy over a file called `memory.x` from the HAL to the root of your project. For nrf52840-hal, this is done automatically so no action is needed. For other HAL crates, see their documentation on where to find an example file.
+
+The `memory.x` file should look something like:
+
+```text
+MEMORY
+{
+  FLASH : ORIGIN = 0x00000000, LENGTH = 1024K
+  RAM   : ORIGIN = 0x20000000, LENGTH = 256K
+}
+```
+
+The `memory.x` file is included in the `cortex-m-rt` linker script `link.x`, and so `link.x` is the one you should tell `rustc` to use (see the `.cargo/config.toml` file where we do that).
+
+### 7. Run!
+
+You are now all set to `cargo-run` your first `defmt`-powered application!
+There are some examples in the `src/bin` directory.
+
+Start by `cargo run`-ning `my-app/src/bin/hello.rs`:
+
+```console
+$ # `rb` is an alias for `run --bin`
+$ cargo rb hello
+    Finished `dev` profile [optimized + debuginfo] target(s) in 0.01s
+     Running `probe-rs run --chip nrf52840_xxaa --log-format=oneline target/thumbv6m-none-eabi/debug/hello`
+      Erasing ✔ 100% [####################]   8.00 KiB @  15.79 KiB/s (took 1s)
+  Programming ✔ 100% [####################]   8.00 KiB @  13.19 KiB/s (took 1s)                                                                                                                        Finished in 1.11s
+Hello, world!
+
+$ echo $?
+0
+```
+
+If you're running out of memory (`flip-link` bails with an overflow error), you can decrease the size of the device memory buffer by setting the `DEFMT_RTT_BUFFER_SIZE` environment variable. The default value is 1024 bytes, and powers of two should be used for optimal performance:
+
+```console
+$ DEFMT_RTT_BUFFER_SIZE=64 cargo rb hello
+```
+
+### (8. Set `rust-analyzer.linkedProjects`)
+
+If you are using [rust-analyzer] with VS Code for IDE-like features you can add following configuration to your `.vscode/settings.json` to make it work transparently across workspaces. Find the details of this option in the [RA docs].
+
+```json
+{
+    "rust-analyzer.linkedProjects": [
+        "Cargo.toml",
+        "firmware/Cargo.toml",
+    ]
+}
+```
+
+[RA docs]: https://rust-analyzer.github.io/manual.html#configuration
+[rust-analyzer]: https://rust-analyzer.github.io/
+
+## Running tests
+
+The template comes configured for running unit tests and integration tests on the target.
+
+Unit tests reside in the library crate and can test private API; the initial set of unit tests are in `src/lib.rs`.
+`cargo test --lib` will run those unit tests.
+
+```console
+$ cargo test --lib
+   Compiling example v0.1.0 (./knurling-rs/example)
+    Finished `test` profile [optimized + debuginfo] target(s) in 0.15s
+     Running unittests src/lib.rs (target/thumbv6m-none-eabi/debug/deps/example-2b0d0e25d141bf57)
+      Erasing ✔ 100% [####################]   8.00 KiB @  15.99 KiB/s (took 1s)
+  Programming ✔ 100% [####################]   8.00 KiB @  13.33 KiB/s (took 1s)                                                                                                                        Finished in 1.10s
+(1/1) running `it_works`...
+all tests passed!
+```
+
+Integration tests reside in the `tests` directory; the initial set of integration tests are in `tests/integration.rs`.
+`cargo test --test integration` will run those integration tests.
+Note that the argument of the `--test` flag must match the name of the test file in the `tests` directory.
+
+```console
+$ cargo test --test integration
+   Compiling example v0.1.0 (./knurling-rs/example)
+    Finished `test` profile [optimized + debuginfo] target(s) in 0.10s
+     Running tests/integration.rs (target/thumbv6m-none-eabi/debug/deps/integration-aaaff41151f6a722)
+      Erasing ✔ 100% [####################]   8.00 KiB @  16.03 KiB/s (took 0s)
+  Programming ✔ 100% [####################]   8.00 KiB @  13.19 KiB/s (took 1s)                                                                                                                        Finished in 1.11s
+(1/1) running `it_works`...
+all tests passed!
+```
+
+Note that to add a new test file to the `tests` directory you also need to add a new `[[test]]` section to `Cargo.toml`.
+
+To run all the tests via `cargo test` the tests need to be explicitly disabled for all the existing binary targets.
+See `Cargo.toml` for details on how to do this.
+
+## Support
+
+`app-template` is part of the [Knurling] project, [Ferrous Systems]' effort at
+improving tooling used to develop for embedded systems.
+
+If you think that our work is useful, consider sponsoring it via [GitHub
+Sponsors].
+
+## License
+
+Licensed under either of
+
+- Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or
+  http://www.apache.org/licenses/LICENSE-2.0)
+
+- MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
+
+at your option.
+
+### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally submitted
+for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
+licensed as above, without any additional terms or conditions.
+
+[Knurling]: https://knurling.ferrous-systems.com
+[Ferrous Systems]: https://ferrous-systems.com/
+[GitHub Sponsors]: https://github.com/sponsors/knurling-rs

usart_async_dma/src/lib.rs

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

usart_async_dma/tests/integration.rs

@@ -0,0 +1,16 @@
+#![no_std]
+#![no_main]
+
+use stm32u5_blinky as _; // memory layout + panic handler
+
+// See https://crates.io/crates/defmt-test/0.3.0 for more documentation (e.g. about the 'state'
+// feature)
+#[defmt_test::tests]
+mod tests {
+    use defmt::assert;
+
+    #[test]
+    fn it_works() {
+        assert!(true)
+    }
+}