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tutorial/04-embedded-no-std-hello/solution/src/main.rs

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+#![no_std]
+#![no_main]
+
+use cortex_m::asm;
+use cortex_m_rt::entry;
+use defmt::info;
+use {defmt_rtt as _, panic_probe as _};
+
+#[entry]
+fn main() -> ! {
+    info!("step04: boot ok");
+
+    loop {
+        asm::delay(8_000_000);
+        info!("step04: alive");
+    }
+}