From 7c1e1ee288bc46dbf030749c242d60e222d1fbe5 Mon Sep 17 00:00:00 2001
From: Bruno Bousquet <21108660+brunob45@users.noreply.github.com>
Date: Tue, 28 May 2024 22:30:10 -0400
Subject: [PATCH] example is working now
---
embassy-stm32/src/timer/input_capture.rs | 63 +++++++++++++++++++-----
examples/stm32f4/.vscode/launch.json | 2 +-
examples/stm32f4/.vscode/tasks.json | 2 +-
3 files changed, 54 insertions(+), 13 deletions(-)
diff --git a/embassy-stm32/src/timer/input_capture.rs b/embassy-stm32/src/timer/input_capture.rs
index a1c1486f9..ab6f10a1d 100644
--- a/embassy-stm32/src/timer/input_capture.rs
+++ b/embassy-stm32/src/timer/input_capture.rs
@@ -26,6 +26,10 @@ pub enum Ch3 {}
/// Channel 4 marker type.
pub enum Ch4 {}
+fn regs_gp16(ptr: *mut ()) -> crate::pac::timer::TimGp16 {
+ unsafe { crate::pac::timer::TimGp16::from_ptr(ptr) }
+}
+
/// Capture pin wrapper.
///
/// This wraps a pin to make it usable with capture.
@@ -76,10 +80,6 @@ impl<'d, T: GeneralInstance4Channel> InputCapture<'d, T> {
freq: Hertz,
counting_mode: CountingMode,
) -> Self {
- Self::new_inner(tim, freq, counting_mode)
- }
-
- fn new_inner(tim: impl Peripheral<P = T> + 'd, freq: Hertz, counting_mode: CountingMode) -> Self {
let mut this = Self { inner: Timer::new(tim) };
this.inner.set_counting_mode(counting_mode);
@@ -148,11 +148,52 @@ impl<'d, T: GeneralInstance4Channel> InputCapture<'d, T> {
}
fn new_future(&self, channel: Channel, mode: InputCaptureMode, tisel: InputTISelection) -> InputCaptureFuture<T> {
- self.inner.enable_channel(channel, true);
- self.inner.set_input_capture_mode(channel, mode);
- self.inner.set_input_ti_selection(channel, tisel);
- self.inner.clear_input_interrupt(channel);
- self.inner.enable_input_interrupt(channel, true);
+ use stm32_metapac::timer::vals::*;
+
+ let regs = regs_gp16(T::regs());
+ let idx = channel.index();
+
+ // Select the active input: TIMx_CCR1 must be linked to the TI1 input, so write the CC1S
+ // bits to 01 in the TIMx_CCMR1 register. As soon as CC1S becomes different from 00,
+ // the channel is configured in input and the TIMx_CCR1 register becomes read-only.
+ regs.ccmr_input(idx / 2)
+ .modify(|r| r.set_ccs(idx % 2, CcmrInputCcs::from(tisel)));
+
+ // Program the appropriate input filter duration in relation with the signal connected to the
+ // timer (by programming the ICxF bits in the TIMx_CCMRx register if the input is one of
+ // the TIx inputs). Let’s imagine that, when toggling, the input signal is not stable during at
+ // must 5 internal clock cycles. We must program a filter duration longer than these 5
+ // clock cycles. We can validate a transition on TI1 when 8 consecutive samples with the
+ // new level have been detected (sampled at fDTS frequency). Then write IC1F bits to
+ // 0011 in the TIMx_CCMR1 register.
+ regs.ccmr_input(idx / 2)
+ .modify(|r| r.set_icf(idx % 2, FilterValue::NOFILTER));
+
+ // Select the edge of the active transition on the TI1 channel by writing the CC1P and
+ // CC1NP bits to 00 in the TIMx_CCER register (rising edge in this case).
+ let ccpnp = match mode {
+ InputCaptureMode::Rising => (false, false),
+ InputCaptureMode::Falling => (false, true),
+ InputCaptureMode::BothEdges => (true, true),
+ };
+ regs.ccer().modify(|r| {
+ r.set_ccp(idx, ccpnp.0);
+ r.set_ccnp(idx, ccpnp.1);
+ });
+
+ // Program the input prescaler. In our example, we wish the capture to be performed at
+ // each valid transition, so the prescaler is disabled (write IC1PS bits to 00 in the
+ // TIMx_CCMR1 register).
+ regs.ccmr_input(idx / 2).modify(|r| r.set_icpsc(idx % 2, 0));
+
+ // Enable capture from the counter into the capture register by setting the CC1E bit in the
+ // TIMx_CCER register.
+ regs.ccer().modify(|r| r.set_cce(idx, true));
+
+ // If needed, enable the related interrupt request by setting the CC1IE bit in the
+ // TIMx_DIER register, and/or the DMA request by setting the CC1DE bit in the
+ // TIMx_DIER register.
+ regs.dier().modify(|r| r.set_ccie(idx, true));
InputCaptureFuture {
channel,
@@ -206,7 +247,7 @@ struct InputCaptureFuture<T: GeneralInstance4Channel> {
impl<T: GeneralInstance4Channel> Drop for InputCaptureFuture<T> {
fn drop(&mut self) {
critical_section::with(|_| {
- let regs = unsafe { crate::pac::timer::TimGp16::from_ptr(T::regs()) };
+ let regs = regs_gp16(T::regs());
// disable interrupt enable
regs.dier().modify(|w| w.set_ccie(self.channel.index(), false));
@@ -220,7 +261,7 @@ impl<T: GeneralInstance4Channel> Future for InputCaptureFuture<T> {
fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
T::state().cc_waker[self.channel.index()].register(cx.waker());
- let regs = unsafe { crate::pac::timer::TimGp16::from_ptr(T::regs()) };
+ let regs = regs_gp16(T::regs());
let dier = regs.dier().read();
if !dier.ccie(self.channel.index()) {
diff --git a/examples/stm32f4/.vscode/launch.json b/examples/stm32f4/.vscode/launch.json
index a9849e0da..20cd4d2e8 100644
--- a/examples/stm32f4/.vscode/launch.json
+++ b/examples/stm32f4/.vscode/launch.json
@@ -15,7 +15,7 @@
"cwd": "${workspaceRoot}",
"preLaunchTask": "Cargo Build (debug)",
"runToEntryPoint": "main",
- "executable": "./target/thumbv7em-none-eabihf/debug/pwm_input",
+ "executable": "./target/thumbv7em-none-eabihf/debug/input_capture",
/* Run `cargo build --example itm` and uncomment this line to run itm example */
// "executable": "./target/thumbv7em-none-eabihf/debug/examples/itm",
"device": "STM32F446RET6",
diff --git a/examples/stm32f4/.vscode/tasks.json b/examples/stm32f4/.vscode/tasks.json
index de7013b12..e153722da 100644
--- a/examples/stm32f4/.vscode/tasks.json
+++ b/examples/stm32f4/.vscode/tasks.json
@@ -9,7 +9,7 @@
],
"args": [
"--bin",
- "pwm_input"
+ "input_capture"
],
"group": {
"kind": "build",