Set up the demo blinky app with a pi pico

pi-usb-serial/.cargo/config

@@ -1,14 +0,0 @@
-[build]
-target = "thumbv6m-none-eabi"
-
-[target.thumbv6m-none-eabi]
-rustflags = [
-    "-C", "link-arg=--nmagic",
-    "-C", "link-arg=-Tlink.x",
-    "-C", "inline-threshold=5",
-    "-C", "no-vectorize-loops",
-]
-
-[target.'cfg(all(target_arch = "arm", target_os = "none"))']
-runner = "elf2uf2-rs -d"
-

pi-usb-serial/.cargo/config.toml

@@ -0,0 +1,6 @@
+[build]
+target = "thumbv6m-none-eabi"
+
+[target.'cfg(all(target_arch = "arm", target_os = "none"))']
+runner = "elf2uf2-rs -d"
+

pi-usb-serial/Cargo.toml

@@ -5,11 +5,14 @@ edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 [dependencies]
-az              = { version = "1" }
-cortex-m-rt     = { version = "0.7.3" }
-cortex-m        = { version = "0.7.7" }
-embedded-alloc  = { version = "0.5.1" }
-embedded-hal    = { version = "0.2.7" }
-panic-halt      = { version = "0.2.0" }
-rp-pico         = { version = "0.8.0" }
+embassy-embedded-hal = { version = "0.1.0", features = ["defmt"] }
+embassy-sync = { version = "0.6.0", features = ["defmt"] }
+embassy-executor = { version = "0.5.0", features = ["task-arena-size-98304", "arch-cortex-m", "executor-thread", "executor-interrupt", "defmt", "integrated-timers"] }
+embassy-time = { version = "0.3.1", features = ["defmt", "defmt-timestamp-uptime"] }
+embassy-rp = { version = "0.1.0", features = ["defmt", "unstable-pac", "time-driver", "critical-section-impl"] }
 
+defmt = "0.3"
+defmt-rtt = "0.4"
+
+cortex-m-rt = "0.7.0"
+panic-probe = { version = "0.3", features = ["print-defmt"] }

pi-usb-serial/build.rs

@@ -4,11 +4,23 @@ use std::io::Write;
 use std::path::PathBuf;
 
 fn main() {
+    // Put `memory.x` in our output directory and ensure it's
+    // on the linker search path.
     let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap());
     File::create(out.join("memory.x"))
         .unwrap()
         .write_all(include_bytes!("memory.x"))
         .unwrap();
     println!("cargo:rustc-link-search={}", out.display());
+
+    // By default, Cargo will re-run a build script whenever
+    // any file in the project changes. By specifying `memory.x`
+    // here, we ensure the build script is only re-run when
+    // `memory.x` is changed.
     println!("cargo:rerun-if-changed=memory.x");
+
+    println!("cargo:rustc-link-arg-bins=--nmagic");
+    println!("cargo:rustc-link-arg-bins=-Tlink.x");
+    println!("cargo:rustc-link-arg-bins=-Tlink-rp.x");
+    println!("cargo:rustc-link-arg-bins=-Tdefmt.x");
 }

pi-usb-serial/src/main.rs

@@ -5,55 +5,26 @@
 #![no_std]
 #![no_main]
 
-use cortex_m::delay::Delay;
-use embedded_hal::digital::v2::OutputPin;
-use panic_halt as _;
-use rp_pico::{
-    entry,
-    hal::{
-        clocks::init_clocks_and_plls,
-        pac::{CorePeripherals, Peripherals},
-        watchdog::Watchdog,
-        Clock, Sio,
-    },
-    Pins,
-};
+use embassy_executor::Spawner;
+use embassy_rp::gpio;
+use embassy_time::Timer;
+use gpio::{Level, Output};
+use defmt::*;
+use defmt_rtt as _;
+use panic_probe as _;
 
-#[entry]
-fn main() -> ! {
-    let mut pac = Peripherals::take().unwrap();
-    let core = CorePeripherals::take().unwrap();
-    let sio = Sio::new(pac.SIO);
-    let pins = Pins::new(
-        pac.IO_BANK0,
-        pac.PADS_BANK0,
-        sio.gpio_bank0,
-        &mut pac.RESETS,
-    );
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let p = embassy_rp::init(Default::default());
+    let mut led = Output::new(p.PIN_25, Level::Low);
 
-    let mut watchdog = Watchdog::new(pac.WATCHDOG);
-    let clocks = init_clocks_and_plls(
-        12_000_000u32,
-        pac.XOSC,
-        pac.CLOCKS,
-        pac.PLL_SYS,
-        pac.PLL_USB,
-        &mut pac.RESETS,
-        &mut watchdog,
-    )
-    .ok()
-    .unwrap();
-
-    let mut delay = Delay::new(core.SYST, clocks.system_clock.freq().to_Hz());
-
-    let mut led_pin = pins.led.into_push_pull_output();
-
-    let delay_ms = 1000;
     loop {
-        let _ = led_pin.set_high();
-        delay.delay_ms(delay_ms);
+        info!("led on!");
+        led.set_high();
+        Timer::after_secs(1).await;
 
-        let _ = led_pin.set_low();
-        delay.delay_ms(delay_ms);
+        info!("led off!");
+        led.set_low();
+        Timer::after_secs(1).await;
     }
 }

rust-toolchain

@@ -1,3 +1,3 @@
 [toolchain]
-channel = "1.77.0"
+channel = "1.80.0"
 targets = [ "wasm32-unknown-unknown", "thumbv6m-none-eabi" ]