embassy-rp: Add Watchdog

examples/rp/src/bin/watchdog.rs

@@ -0,0 +1,48 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+use defmt::info;
+use embassy_executor::Spawner;
+use embassy_rp::gpio;
+use embassy_rp::watchdog::*;
+use embassy_time::{Duration, Timer};
+use gpio::{Level, Output};
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let p = embassy_rp::init(Default::default());
+    info!("Hello world!");
+
+    let mut watchdog = Watchdog::new(p.WATCHDOG);
+    let mut led = Output::new(p.PIN_25, Level::Low);
+
+    // Set the LED high for 2 seconds so we know when we're about to start the watchdog
+    led.set_high();
+    Timer::after(Duration::from_secs(2)).await;
+
+    // Set to watchdog to reset if it's not reloaded within 1.05 seconds, and start it
+    watchdog.start(Duration::from_millis(1_050));
+    info!("Started the watchdog timer");
+
+    // Blink once a second for 5 seconds, refreshing the watchdog timer once a second to avoid a reset
+    for _ in 1..=5 {
+        led.set_low();
+        Timer::after(Duration::from_millis(500)).await;
+        led.set_high();
+        Timer::after(Duration::from_millis(500)).await;
+        info!("Feeding watchdog");
+        watchdog.feed();
+    }
+
+    info!("Stopped feeding, device will reset in 1.05 seconds");
+    // Blink 10 times per second, not feeding the watchdog.
+    // The processor should reset in 1.05 seconds, or 5 blinks time
+    loop {
+        led.set_low();
+        Timer::after(Duration::from_millis(100)).await;
+        led.set_high();
+        Timer::after(Duration::from_millis(100)).await;
+    }
+}