change existing pwm example to reflect both existing ways to use pwm output

1 files changed, 48 insertions, 7 deletions

diff --git a/examples/rp23/src/bin/pwm.rs b/examples/rp23/src/bin/pwm.rs
index 15eae09ee..7314ee637 100644
--- a/examples/rp23/src/bin/pwm.rs
+++ b/examples/rp23/src/bin/pwm.rs
@@ -1,6 +1,8 @@
-//! This example shows how to use PWM (Pulse Width Modulation) in the RP2040 chip.
+//! This example shows how to use PWM (Pulse Width Modulation) in the RP235x chip.
 //!
-//! The LED on the RP Pico W board is connected differently. Add a LED and resistor to another pin.
+//! We demonstrate two ways of using PWM:
+//! 1. Via config
+//! 2. Via setting a duty cycle
 
 #![no_std]
 #![no_main]
@@ -8,8 +10,10 @@
 use defmt::*;
 use embassy_executor::Spawner;
 use embassy_rp::block::ImageDef;
-use embassy_rp::pwm::{Config, Pwm};
+use embassy_rp::peripherals::{PIN_25, PIN_4, PWM_SLICE2, PWM_SLICE4};
+use embassy_rp::pwm::{Config, Pwm, SetDutyCycle};
 use embassy_time::Timer;
+// use embedded_hal_1::pwm::SetDutyCycle;
 use {defmt_rtt as _, panic_probe as _};
 
 #[link_section = ".start_block"]
@@ -17,13 +21,22 @@ use {defmt_rtt as _, panic_probe as _};
 pub static IMAGE_DEF: ImageDef = ImageDef::secure_exe();
 
 #[embassy_executor::main]
-async fn main(_spawner: Spawner) {
+async fn main(spawner: Spawner) {
     let p = embassy_rp::init(Default::default());
+    spawner.spawn(pwm_set_config(p.PWM_SLICE4, p.PIN_25)).unwrap();
+    spawner.spawn(pwm_set_dutycycle(p.PWM_SLICE2, p.PIN_4)).unwrap();
+}
 
-    let mut c: Config = Default::default();
-    c.top = 0x8000;
+/// Demonstrate PWM by modifying & applying the config
+///
+/// Using the onboard led, if You are using a different Board than plain Pico2 (i.e. W variant)
+/// you must use another slice & pin and an appropriate resistor.
+#[embassy_executor::task]
+async fn pwm_set_config(slice4: PWM_SLICE4, pin25: PIN_25) {
+    let mut c = Config::default();
+    c.top = 32_768;
     c.compare_b = 8;
-    let mut pwm = Pwm::new_output_b(p.PWM_SLICE4, p.PIN_25, c.clone());
+    let mut pwm = Pwm::new_output_b(slice4, pin25, c.clone());
 
     loop {
         info!("current LED duty cycle: {}/32768", c.compare_b);
@@ -32,3 +45,31 @@ async fn main(_spawner: Spawner) {
         pwm.set_config(&c);
     }
 }
+
+/// Demonstrate PWM by setting duty cycle
+///
+/// Using GP4 in Slice2, make sure to use an appropriate resistor.
+#[embassy_executor::task]
+async fn pwm_set_dutycycle(slice2: PWM_SLICE2, pin4: PIN_4) {
+    let mut c = Config::default();
+    c.top = 32_768;
+    let mut pwm = Pwm::new_output_a(slice2, pin4, c.clone());
+
+    loop {
+        // 100% duty cycle, fully on
+        pwm.set_duty_cycle_fully_on().unwrap();
+        Timer::after_secs(1).await;
+
+        // 50% duty cycle, half on. Expressed as simple percentage.
+        pwm.set_duty_cycle_percent(50).unwrap();
+        Timer::after_secs(1).await;
+
+        // 25% duty cycle, quarter on. Expressed as (duty / max_duty)
+        pwm.set_duty_cycle(8_192 / c.top).unwrap();
+        Timer::after_secs(1).await;
+
+        // 0% duty cycle, fully off.
+        pwm.set_duty_cycle_fully_off().unwrap();
+        Timer::after_secs(1).await;
+    }
+}