f0 blinky in 3084 bytes

examples/stm32f0/.cargo/config.toml

@@ -1,3 +1,18 @@
+[unstable]
+# enabling these breaks the float tests during linking, with intrinsics
+# duplicated between embassy-rp and compilter_builtins
+build-std = ["core"]
+build-std-features = ["panic_immediate_abort"]
+
+[target.'cfg(all(target_arch = "arm", target_os = "none"))']
+runner = "teleprobe client run"
+#runner = "teleprobe local run --chip RP2040 --elf"
+
+rustflags = [
+  # Code-size optimizations.
+  "-Z", "trap-unreachable=no",
+]
+
 [target.thumbv6m-none-eabi]
 runner = 'probe-rs run --chip STM32F091RCTX'
 

examples/stm32f0/Cargo.toml

@@ -8,16 +8,16 @@ license = "MIT OR Apache-2.0"
 
 [dependencies]
 # Change stm32f091rc to your chip name, if necessary.
-embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "memory-x", "stm32f091rc", "time-driver-any", "exti", "unstable-pac"] }
+embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly",  "memory-x", "stm32f091rc", "time-driver-any", "unstable-pac"] }
 cortex-m = { version = "0.7.6", features = ["inline-asm", "critical-section-single-core"] }
 cortex-m-rt = "0.7.0"
-defmt = "0.3"
-defmt-rtt = "0.4"
-panic-probe = "0.3"
-embassy-sync = { version = "0.3.0", path = "../../embassy-sync", features = ["defmt"] }
-embassy-executor = { version = "0.3.0", path = "../../embassy-executor", features = ["nightly", "arch-cortex-m", "executor-thread", "executor-interrupt", "defmt", "integrated-timers"] }
-embassy-time = { version = "0.1.3", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
+embassy-sync = { version = "0.3.0", path = "../../embassy-sync", features = [] }
+embassy-executor = { version = "0.3.0", path = "../../embassy-executor", features = ["nightly", "arch-cortex-m", "executor-thread", "integrated-timers"] }
+embassy-time = { version = "0.1.3", path = "../../embassy-time", features = [ "tick-hz-32_768"] }
 static_cell = { version = "1.1", features = ["nightly"]}
+panic-halt = "0.2.0"
 
 [profile.release]
 debug = 2
+opt-level = 's'
+lto = 'fat'

examples/stm32f0/build.rs

@@ -1,5 +1,4 @@
 fn main() {
     println!("cargo:rustc-link-arg-bins=--nmagic");
     println!("cargo:rustc-link-arg-bins=-Tlink.x");
-    println!("cargo:rustc-link-arg-bins=-Tdefmt.x");
 }

examples/stm32f0/src/bin/blinky.rs

@@ -2,26 +2,21 @@
 #![no_main]
 #![feature(type_alias_impl_trait)]
 
-use defmt::*;
 use embassy_executor::Spawner;
 use embassy_stm32::gpio::{Level, Output, Speed};
 use embassy_time::{Duration, Timer};
-use {defmt_rtt as _, panic_probe as _};
+use panic_halt as _;
 
 // main is itself an async function.
 #[embassy_executor::main]
 async fn main(_spawner: Spawner) {
     let p = embassy_stm32::init(Default::default());
-    info!("Hello World!");
     //PA5 is the onboard LED on the Nucleo F091RC
     let mut led = Output::new(p.PA5, Level::High, Speed::Low);
 
     loop {
-        info!("high");
         led.set_high();
         Timer::after(Duration::from_millis(300)).await;
-
-        info!("low");
         led.set_low();
         Timer::after(Duration::from_millis(300)).await;
     }