From e056bedd553e7fbc7d28f8f516c87fcd12859aef Mon Sep 17 00:00:00 2001
From: Matous Hybl <hyblmatous@gmail.com>
Date: Wed, 8 Dec 2021 17:39:59 +0100
Subject: Port the PWM example to H7, add low-level API example implementing
 32-bit PWM.

---
 examples/stm32h7/src/bin/low_level_timer_api.rs | 147 ++++++++++++++++++++++++
 1 file changed, 147 insertions(+)
 create mode 100644 examples/stm32h7/src/bin/low_level_timer_api.rs

(limited to 'examples/stm32h7/src/bin/low_level_timer_api.rs')

diff --git a/examples/stm32h7/src/bin/low_level_timer_api.rs b/examples/stm32h7/src/bin/low_level_timer_api.rs
new file mode 100644
index 000000000..2640f249d
--- /dev/null
+++ b/examples/stm32h7/src/bin/low_level_timer_api.rs
@@ -0,0 +1,147 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+#[path = "../example_common.rs"]
+mod example_common;
+use core::marker::PhantomData;
+
+use embassy::executor::Spawner;
+use embassy::time::{Duration, Timer};
+use embassy::util::Unborrow;
+use embassy_hal_common::unborrow;
+use embassy_stm32::gpio::NoPin;
+use embassy_stm32::pwm::{pins::*, Channel, OutputCompareMode};
+use embassy_stm32::time::{Hertz, U32Ext};
+use embassy_stm32::timer::GeneralPurpose32bitInstance;
+use embassy_stm32::{Config, Peripherals};
+use example_common::*;
+
+pub fn config() -> Config {
+    let mut config = Config::default();
+    config.rcc.sys_ck = Some(400.mhz().into());
+    config.rcc.hclk = Some(400.mhz().into());
+    config.rcc.pll1.q_ck = Some(100.mhz().into());
+    config.rcc.pclk1 = Some(100.mhz().into());
+    config.rcc.pclk2 = Some(100.mhz().into());
+    config.rcc.pclk3 = Some(100.mhz().into());
+    config.rcc.pclk4 = Some(100.mhz().into());
+    config
+}
+
+#[embassy::main(config = "config()")]
+async fn main(_spawner: Spawner, p: Peripherals) {
+    info!("Hello World!");
+
+    let mut pwm = SimplePwm32::new(p.TIM5, p.PA0, NoPin, NoPin, NoPin, 10000.hz());
+    let max = pwm.get_max_duty();
+    pwm.enable(Channel::Ch1);
+
+    info!("PWM initialized");
+    info!("PWM max duty {}", max);
+
+    loop {
+        pwm.set_duty(Channel::Ch1, 0);
+        Timer::after(Duration::from_millis(300)).await;
+        pwm.set_duty(Channel::Ch1, max / 4);
+        Timer::after(Duration::from_millis(300)).await;
+        pwm.set_duty(Channel::Ch1, max / 2);
+        Timer::after(Duration::from_millis(300)).await;
+        pwm.set_duty(Channel::Ch1, max - 1);
+        Timer::after(Duration::from_millis(300)).await;
+    }
+}
+pub struct SimplePwm32<'d, T: GeneralPurpose32bitInstance> {
+    phantom: PhantomData<&'d mut T>,
+    inner: T,
+}
+
+impl<'d, T: GeneralPurpose32bitInstance> SimplePwm32<'d, T> {
+    pub fn new<F: Into<Hertz>>(
+        tim: impl Unborrow<Target = T> + 'd,
+        ch1: impl Unborrow<Target = impl Channel1Pin<T>> + 'd,
+        ch2: impl Unborrow<Target = impl Channel2Pin<T>> + 'd,
+        ch3: impl Unborrow<Target = impl Channel3Pin<T>> + 'd,
+        ch4: impl Unborrow<Target = impl Channel4Pin<T>> + 'd,
+        freq: F,
+    ) -> Self {
+        unborrow!(tim, ch1, ch2, ch3, ch4);
+
+        T::enable();
+        <T as embassy_stm32::rcc::low_level::RccPeripheral>::reset();
+
+        unsafe {
+            ch1.configure();
+            ch2.configure();
+            ch3.configure();
+            ch4.configure();
+        }
+
+        let mut this = Self {
+            inner: tim,
+            phantom: PhantomData,
+        };
+
+        this.set_freq(freq);
+        this.inner.start();
+
+        unsafe {
+            this.inner
+                .regs_gp32()
+                .ccmr_output(0)
+                .modify(|w| w.set_ocm(0, OutputCompareMode::PwmMode1.into()));
+            this.inner
+                .regs_gp32()
+                .ccmr_output(0)
+                .modify(|w| w.set_ocm(1, OutputCompareMode::PwmMode1.into()));
+            this.inner
+                .regs_gp32()
+                .ccmr_output(1)
+                .modify(|w| w.set_ocm(0, OutputCompareMode::PwmMode1.into()));
+            this.inner
+                .regs_gp32()
+                .ccmr_output(1)
+                .modify(|w| w.set_ocm(1, OutputCompareMode::PwmMode1.into()));
+        }
+        this
+    }
+
+    pub fn enable(&mut self, channel: Channel) {
+        unsafe {
+            self.inner
+                .regs_gp32()
+                .ccer()
+                .modify(|w| w.set_cce(channel.raw(), true));
+        }
+    }
+
+    pub fn disable(&mut self, channel: Channel) {
+        unsafe {
+            self.inner
+                .regs_gp32()
+                .ccer()
+                .modify(|w| w.set_cce(channel.raw(), false));
+        }
+    }
+
+    pub fn set_freq<F: Into<Hertz>>(&mut self, freq: F) {
+        <T as embassy_stm32::timer::low_level::GeneralPurpose32bitInstance>::set_frequency(
+            &mut self.inner,
+            freq,
+        );
+    }
+
+    pub fn get_max_duty(&self) -> u32 {
+        unsafe { self.inner.regs_gp32().arr().read().arr() }
+    }
+
+    pub fn set_duty(&mut self, channel: Channel, duty: u32) {
+        defmt::assert!(duty < self.get_max_duty());
+        unsafe {
+            self.inner
+                .regs_gp32()
+                .ccr(channel.raw())
+                .modify(|w| w.set_ccr(duty))
+        }
+    }
+}
-- 
cgit