stm32/hrtim: add example impl.

examples/stm32f334/src/bin/hello.rs

@@ -0,0 +1,23 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+use defmt::info;
+use embassy_executor::Spawner;
+use embassy_stm32::time::Hertz;
+use embassy_stm32::Config;
+use embassy_time::{Duration, Timer};
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) -> ! {
+    let mut config = Config::default();
+    config.rcc.hse = Some(Hertz(8_000_000));
+    config.rcc.sysclk = Some(Hertz(16_000_000));
+    let _p = embassy_stm32::init(config);
+
+    loop {
+        info!("Hello World!");
+        Timer::after(Duration::from_secs(1)).await;
+    }
+}