Update documentation

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 * Add support for Raspberry Pi Compute Module 5.
 * **Gpio**: Add `set_bias` to `InputPin` (contributed by @KronsyC).
+* **Gpio**: Add shared state button example (contributed by @CosminPerRam).
 * **Spi**: Fix embedded HAL `SimpleHalSpiDevice` transactions to keep CS low between operations (contributed by @whatisbyandby).
 * **Spi**: (Breaking change) Change `SimpleHalSpiDevice::new()` to require an `Spi` instance, instead of a generic HAL bus (contributed by @whatisbyandby).
 

examples/gpio_shared_button_state.rs

@@ -1,16 +1,16 @@
 // gpio_shared_button_state.rs - Stops the program until a certain amount of event input changes via
-// a non-global shared variable (that can be done using OnceCell for example), this requires a Mutex
-// as it goes across threads and Arc to make sure we have the same entry everywhere.
+// a non-global shared variable (that can be done using OnceCell for example). This requires a Mutex
+// as it goes across threads, and Arc to make sure we have the same entry everywhere.
 
+use rppal::gpio::{Event, Gpio, Trigger};
 use std::error::Error;
 use std::sync::{Arc, Mutex};
 use std::time::Duration;
-use rppal::gpio::{Gpio, Event, Trigger};
 
 const INPUT_PIN_GPIO: u8 = 27;
 const STOP_AFTER_N_CHANGES: u8 = 5;
 
-// The function we will run upon a Trigger
+// The function we will run upon a Trigger.
 fn input_callback(event: Event, my_data: Arc<Mutex<u8>>) {
     println!("Event: {:?}", event);
     *my_data.lock().unwrap() += 1;
@@ -23,26 +23,26 @@ fn main() -> Result<(), Box<dyn Error>> {
     // Configure the input pin.
     let mut input_pin = Gpio::new()?.get(INPUT_PIN_GPIO)?.into_input_pulldown();
 
-    // We need to clone this as set_async_interrupt will move it and cant be used afterward if so
+    // We need to clone this as set_async_interrupt will move it, which means it can't be accessed afterwards.
     let shared_state_hold = shared_state.clone();
     input_pin.set_async_interrupt(
         Trigger::FallingEdge,
         Some(Duration::from_millis(50)),
         move |event| {
-            // Note: you can also add more parameters here!
+            // Note: you could add more parameters here!
             input_callback(event, shared_state_hold.clone());
         },
     )?;
 
-    // We check constantly if we have reached our number of changes.
+    // We constantly check if we have reached our number of changes.
     loop {
         if *shared_state.lock().unwrap() >= STOP_AFTER_N_CHANGES {
             // Reached it, exiting the program.
             println!("Reached {STOP_AFTER_N_CHANGES} events, exiting...");
             break;
         }
 
-        // Suppose we do some work here that takes a second, the shorter the work takes, the quicker
+        // Suppose we do some work here that takes a second. The shorter the work takes, the quicker
         // we will quit upon reaching our condition.
         println!("Still waiting...");
         std::thread::sleep(Duration::from_secs(1));