From 5b6e35189a7d6d392acb2e5232d7fa5ae2b4e374 Mon Sep 17 00:00:00 2001
From: Edward Shen <code@eddie.sh>
Date: Sat, 17 May 2025 00:09:10 -0700
Subject: [PATCH] tweak period calculation in song pwm code

---
 src/main.rs | 21 ++++++---------------
 1 file changed, 6 insertions(+), 15 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 6fe9971..dd49811 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -99,19 +99,6 @@ async fn heartbeat(mut control: Control<'static>) {
 
 #[embassy_executor::main]
 async fn main(spawner: Spawner) {
-    // let p = embassy_rp::init(Default::default());
-    // let mut led = Output::new(p.PIN_18, Level::Low);
-
-    // loop {
-    //     info!("led on!");
-    //     led.set_high();
-    //     Timer::after_secs(1).await;
-
-    //     info!("led off!");
-    //     led.set_low();
-    //     Timer::after_secs(1).await;
-    // }
-
     let mut p = embassy_rp::init(embassy_rp::config::Config::default());
     let fw = include_bytes!("../embassy/cyw43-firmware/43439A0.bin");
     let clm = include_bytes!("../embassy/cyw43-firmware/43439A0_clm.bin");
@@ -214,7 +201,7 @@ async fn play_music(slice: &mut PWM_SLICE2, pin: &mut PIN_20) {
         F4 = 349,
         G4 = 392,
         A5 = 440,
-        #[allow(dead_code)]
+        #[expect(dead_code)]
         B5 = 494,
         C5 = 524,
     }
@@ -282,7 +269,11 @@ async fn play_music(slice: &mut PWM_SLICE2, pin: &mut PIN_20) {
         let clock_freq_hz = embassy_rp::clocks::clk_sys_freq();
         let divider = 16;
         #[expect(clippy::cast_possible_truncation)]
-        let period = clock_freq_hz.saturating_div(note as u32 * u32::from(divider)) as u16 - 1;
+        let period = clock_freq_hz
+            .checked_div(note as u32 * u32::from(divider))
+            .unwrap_or_default()
+            .checked_sub(1)
+            .unwrap_or(1) as u16;
 
         let mut c = pwm::Config::default();
         c.top = period;