Introduce clkout peripheral (#36)

Introduces a ClockOut peripheral, allowing for ensuring that internal clocks are operating correctly.

Also fixes some incorrect PLL/Div4 usage.

1 files changed, 69 insertions, 0 deletions

diff --git a/examples/src/bin/clkout.rs b/examples/src/bin/clkout.rs
new file mode 100644
index 000000000..bfd963540
--- /dev/null
+++ b/examples/src/bin/clkout.rs
@@ -0,0 +1,69 @@
+#![no_std]
+#![no_main]
+
+use embassy_executor::Spawner;
+use embassy_mcxa::clkout::{ClockOut, ClockOutSel, Config, Div4};
+use embassy_mcxa::clocks::PoweredClock;
+use embassy_mcxa::gpio::{DriveStrength, SlewRate};
+use embassy_mcxa::{Level, Output};
+use embassy_time::Timer;
+use {defmt_rtt as _, embassy_mcxa as hal, panic_probe as _};
+
+/// Demonstrate CLKOUT, using Pin P4.2
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let p = hal::init(hal::config::Config::default());
+    let mut pin = p.P4_2;
+    let mut clkout = p.CLKOUT;
+
+    loop {
+        defmt::info!("Set Low...");
+        let mut output = Output::new(pin.reborrow(), Level::Low, DriveStrength::Normal, SlewRate::Slow);
+        Timer::after_millis(500).await;
+
+        defmt::info!("Set High...");
+        output.set_high();
+        Timer::after_millis(400).await;
+
+        defmt::info!("Set Low...");
+        output.set_low();
+        Timer::after_millis(500).await;
+
+        defmt::info!("16k...");
+        // Run Clock Out with the 16K clock
+        let _clock_out = ClockOut::new(
+            clkout.reborrow(),
+            pin.reborrow(),
+            Config {
+                sel: ClockOutSel::Clk16K,
+                div: Div4::no_div(),
+                level: PoweredClock::NormalEnabledDeepSleepDisabled,
+            },
+        )
+        .unwrap();
+
+        Timer::after_millis(3000).await;
+
+        defmt::info!("Set Low...");
+        drop(_clock_out);
+
+        let _output = Output::new(pin.reborrow(), Level::Low, DriveStrength::Normal, SlewRate::Slow);
+        Timer::after_millis(500).await;
+
+        // Run Clock Out with the 12M clock, divided by 3
+        defmt::info!("4M...");
+        let _clock_out = ClockOut::new(
+            clkout.reborrow(),
+            pin.reborrow(),
+            Config {
+                sel: ClockOutSel::Fro12M,
+                div: const { Div4::from_divisor(3).unwrap() },
+                level: PoweredClock::NormalEnabledDeepSleepDisabled,
+            },
+        )
+        .unwrap();
+
+        // Let it run for 3 seconds...
+        Timer::after_millis(3000).await;
+    }
+}