Update PWM example with latest pwm changes

Author: TheZoq2

examples/pwm.rs

@@ -10,7 +10,7 @@ use cortex_m::asm;
 use stm32f1xx_hal::{
     prelude::*,
     pac,
-    timer::Timer,
+    timer::{Tim2NoRemap, Timer},
 };
 use cortex_m_rt::entry;
 
@@ -25,14 +25,16 @@ fn main() -> ! {
 
     let mut afio = p.AFIO.constrain(&mut rcc.apb2);
 
-    // let mut gpioa = p.GPIOA.split(&mut rcc.apb2);
-    let mut gpiob = p.GPIOB.split(&mut rcc.apb2);
+    let mut gpioa = p.GPIOA.split(&mut rcc.apb2);
+    // let mut gpiob = p.GPIOB.split(&mut rcc.apb2);
 
     // TIM2
     let c1 = gpioa.pa0.into_alternate_push_pull(&mut gpioa.crl);
     let c2 = gpioa.pa1.into_alternate_push_pull(&mut gpioa.crl);
     let c3 = gpioa.pa2.into_alternate_push_pull(&mut gpioa.crl);
-    let c4 = gpioa.pa3.into_alternate_push_pull(&mut gpioa.crl);
+    // If you don't want to use all channels, just leave some out
+    // let c4 = gpioa.pa3.into_alternate_push_pull(&mut gpioa.crl);
+    let pins = (c1, c2, c3);
 
     // TIM3
     // let c1 = gpioa.pa6.into_alternate_push_pull(&mut gpioa.crl);
@@ -46,9 +48,9 @@ fn main() -> ! {
     // let c3 = gpiob.pb8.into_alternate_push_pull(&mut gpiob.crh);
     // let c4 = gpiob.pb9.into_alternate_push_pull(&mut gpiob.crh);
 
-    let mut pwm = Timer::tim4(p.TIM4, &clocks, &mut rcc.apb1)
-        .pwm((c1, c2, c3, c4), &mut afio.mapr, 1.khz())
-        .3;
+    let mut pwm = Timer::tim2(p.TIM2, &clocks, &mut rcc.apb1)
+        .pwm::<Tim2NoRemap, _, _, _>(pins, &mut afio.mapr, 1.khz())
+        .2;
 
     let max = pwm.get_max_duty();
 

src/pwm.rs

@@ -13,12 +13,24 @@
 
   ```rust
   let gpioa = ..; // Set up and split GPIOA
+  // Select the pins you want to use
   let pins = (
       gpioa.pa0.into_alternate_push_pull(&mut gpioa.crl),
       gpioa.pa1.into_alternate_push_pull(&mut gpioa.crl),
       gpioa.pa2.into_alternate_push_pull(&mut gpioa.crl),
       gpioa.pa3.into_alternate_push_pull(&mut gpioa.crl),
   );
+
+  // Set up the timer as a PWM output. Since there are multiple remap
+  // options for tim2 that use the same pins, you need to specify
+  // the remap generic parameter.
+  let (c1, c2, c3, c4) = Timer::tim2(p.TIM2, &clocks, &mut rcc.apb1)
+      .pwm::<Tim2NoRemap, _, _, _>(pins, &mut afio.mapr, 1.khz())
+      .3;
+
+  // Start using the channels
+  c1.set_duty(c1.get_max_duty());
+  // ...
   ```
 
   Then call the `pwm` function on the corresponding timer.

src/qei.rs

@@ -1,4 +1,10 @@
-//! # Quadrature Encoder Interface
+/**
+  # Quadrature Encoder Interface
+
+  NOTE: In some cases you need to specify remap you need, especially for TIM2
+  (see [Alternate function remapping](super::timer)):
+*/
+
 use core::u16;
 
 use core::marker::PhantomData;

src/timer.rs

@@ -3,6 +3,9 @@
 
   ## Alternate function remapping
 
+  This is a list of the remap settings you can use to assign pins to PWM channels
+  and the QEI peripherals
+
   ### TIM1
 
   Not available on STM32F101.