feat: stop/start chase with button press

Cargo.lock

@@ -284,6 +284,7 @@ dependencies = [
 name = "esp32c3-playground"
 version = "0.1.0"
 dependencies = [
+ "critical-section",
  "esp-hal",
  "panic-halt",
 ]

Cargo.toml

@@ -6,5 +6,6 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+critical-section = "1.1.2"
 esp-hal = { version = "0.17.0", features = ["esp32c3"] }
 panic-halt = "0.2.0"

src/main.rs

@@ -1,15 +1,35 @@
 #![no_std]
 #![no_main]
 
+use core::cell::Cell;
+
+use critical_section::Mutex;
+
 use esp_hal::clock::ClockControl;
 use esp_hal::delay::Delay;
-use esp_hal::gpio::IO;
+use esp_hal::gpio::{Event, IO};
 use esp_hal::ledc::{channel, timer, LSGlobalClkSource, LEDC};
 use esp_hal::peripherals::Peripherals;
 use esp_hal::prelude::*;
+use esp_hal::systimer::SystemTimer;
 
 use panic_halt as _;
 
+const BUTTON_TIMEOUT: u64 = SystemTimer::TICKS_PER_SECOND / 10;
+
+const COLORS: [[u8; 3]; 6] = [
+    [1, 0, 0],
+    [1, 1, 0],
+    [0, 1, 0],
+    [0, 1, 1],
+    [0, 0, 1],
+    [1, 0, 1],
+];
+
+static LAST_TRIGGERED: Mutex<Cell<u64>> = Mutex::new(Cell::new(0));
+
+static STOP_CHASE: Mutex<Cell<bool>> = Mutex::new(Cell::new(false));
+
 #[entry]
 fn main() -> ! {
     let p = Peripherals::take();
@@ -28,7 +48,9 @@ fn main() -> ! {
         })
         .unwrap();
 
-    let io = IO::new(p.GPIO, p.IO_MUX);
+    let mut io = IO::new(p.GPIO, p.IO_MUX);
+
+    io.set_interrupt_handler(gpio_handler);
 
     let mut r = ledc.get_channel(
         channel::Number::Channel0,
@@ -62,27 +84,35 @@ fn main() -> ! {
     })
     .unwrap();
 
-    let _btn = io.pins.gpio9.into_pull_up_input();
+    io.pins.gpio9.into_pull_up_input().listen(Event::RisingEdge);
 
     let delay = Delay::new(&clocks);
 
-    for [r_state, g_state, b_state] in [
+    for [r_duty, g_duty, b_duty] in COLORS.iter().cycle() {
-        [1, 0, 0],
+        let stop_chase = critical_section::with(|cs| STOP_CHASE.borrow(cs).get());
-        [1, 1, 0],
+        if !stop_chase {
-        [0, 1, 0],
+            let _ = r.set_duty(*r_duty);
-        [0, 1, 1],
+            let _ = g.set_duty(*g_duty);
-        [0, 0, 1],
+            let _ = b.set_duty(*b_duty);
-        [1, 0, 1],
+        }
-    ]
-    .iter()
-    .cycle()
-    {
-        let _ = r.set_duty(*r_state);
-        let _ = g.set_duty(*g_state);
-        let _ = b.set_duty(*b_state);
 
         delay.delay_millis(200u32);
     }
 
     loop {}
 }
+
+#[handler]
+fn gpio_handler() {
+    critical_section::with(|cs| {
+        let last_triggered = LAST_TRIGGERED.borrow(cs);
+        if last_triggered.get() + BUTTON_TIMEOUT > SystemTimer::now() {
+            return;
+        }
+
+        let stop_chase = STOP_CHASE.borrow(cs);
+        stop_chase.set(!stop_chase.get());
+
+        last_triggered.set(SystemTimer::now());
+    });
+}