working log via usb example

.cargo/config.toml

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+[target.'cfg(all(target_arch = "arm", target_os = "none"))']
+runner = "elf2uf2-rs -d -s"
+
+[build]
+target = "thumbv6m-none-eabi"        # Cortex-M0 and Cortex-M0+
+
+[env]
+DEFMT_LOG = "debug"

.gitignore

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

Cargo.toml

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+[package]
+name = "pico-website"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+embassy-executor = {version="*", features = ["task-arena-size-32768", "arch-cortex-m", "executor-thread", "executor-interrupt", "defmt"]}
+embassy-rp = {version ="*", features = ["rp2040", "time-driver", "critical-section-impl"] }
+embassy-time = "*"
+embassy-usb-logger = "*"
+
+defmt-rtt = "*"
+panic-probe = "*"
+cortex-m = { version = "*", features = ["inline-asm"] }
+cortex-m-rt = "*"
+
+log = "*"

build.rs

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+//! This build script copies the `memory.x` file from the crate root into
+//! a directory where the linker can always find it at build time.
+//! For many projects this is optional, as the linker always searches the
+//! project root directory -- wherever `Cargo.toml` is. However, if you
+//! are using a workspace or have a more complicated build setup, this
+//! build script becomes required. Additionally, by requesting that
+//! Cargo re-run the build script whenever `memory.x` is changed,
+//! updating `memory.x` ensures a rebuild of the application with the
+//! new memory settings.
+
+use std::env;
+use std::fs::File;
+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");
+}

memory.x

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+MEMORY {
+    BOOT2 : ORIGIN = 0x10000000, LENGTH = 0x100
+    FLASH : ORIGIN = 0x10000100, LENGTH = 2048K - 0x100
+
+    /* Pick one of the two options for RAM layout     */
+
+    /* OPTION A: Use all RAM banks as one big block   */
+    /* Reasonable, unless you are doing something     */
+    /* really particular with DMA or other concurrent */
+    /* access that would benefit from striping        */
+    RAM   : ORIGIN = 0x20000000, LENGTH = 264K
+
+    /* OPTION B: Keep the unstriped sections separate */
+    /* RAM: ORIGIN = 0x20000000, LENGTH = 256K        */
+    /* SCRATCH_A: ORIGIN = 0x20040000, LENGTH = 4K    */
+    /* SCRATCH_B: ORIGIN = 0x20041000, LENGTH = 4K    */
+}

src/main.rs

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+#![no_std]
+#![no_main]
+
+use embassy_executor::Spawner;
+use embassy_rp::bind_interrupts;
+use embassy_rp::peripherals::USB;
+use embassy_rp::usb::{Driver, InterruptHandler};
+use embassy_time::Timer;
+use {defmt_rtt as _, panic_probe as _};
+
+bind_interrupts!(struct Irqs {
+    USBCTRL_IRQ => InterruptHandler<USB>;
+});
+
+#[embassy_executor::task]
+async fn logger_task(driver: Driver<'static, USB>) {
+    embassy_usb_logger::run!(1024, log::LevelFilter::Info, driver);
+}
+
+#[embassy_executor::main]
+async fn main(spawner: Spawner) {
+    let p = embassy_rp::init(Default::default());
+    let driver = Driver::new(p.USB, Irqs);
+    spawner.spawn(logger_task(driver)).unwrap();
+
+    let mut counter = 0;
+    loop {
+        counter += 1;
+        log::info!("Tick {}", counter);
+        Timer::after_secs(1).await;
+    }
+}