second adc added to example + API todos completed

embassy-stm32/src/adc/ringbuffered_v2.rs

@@ -315,7 +315,7 @@ impl<'d, T: Instance> RingBufferedAdc<'d, T> {
     ///
     /// Receive in the background is terminated if an error is returned.
     /// It must then manually be started again by calling `start()` or by re-calling `read()`.
-    pub async fn read<const N: usize>(&mut self, buf: &mut [u16; N]) -> Result<usize, OverrunError> {
+    pub fn read<const N: usize>(&mut self, buf: &mut [u16; N]) -> Result<usize, OverrunError> {
         let r = T::regs();
 
         // Start background receive if it was not already started
@@ -325,11 +325,7 @@ impl<'d, T: Instance> RingBufferedAdc<'d, T> {
 
         // Clear overrun flag if set.
         if r.sr().read().ovr() {
-            r.sr().modify(|regs| {
+            return self.stop(OverrunError);
-                regs.set_ovr(false);
-                // regs.set_eoc(false);
-            });
-            // return self.stop(OverrunError);
         }
 
         loop {
@@ -355,11 +351,7 @@ impl<'d, T: Instance> RingBufferedAdc<'d, T> {
 
         // Clear overrun flag if set.
         if r.sr().read().ovr() {
-            r.sr().modify(|regs| {
+            return self.stop(OverrunError);
-                regs.set_ovr(false);
-                // regs.set_eoc(false);
-            });
-            // return self.stop(OverrunError);
         }
         match self.ring_buf.read_exact(buf).await {
             Ok(len) => Ok(len),

examples/stm32f4/src/bin/adc_dma.rs

@@ -13,15 +13,18 @@ async fn main(_spawner: Spawner) {
     let mut p = embassy_stm32::init(Default::default());
 
     let adc_data: &mut [u16; ADC_BUF_SIZE] = singleton!(ADCDAT : [u16; ADC_BUF_SIZE] = [0u16; ADC_BUF_SIZE]).unwrap();
+    let adc_data2: &mut [u16; ADC_BUF_SIZE] = singleton!(ADCDAT2 : [u16; ADC_BUF_SIZE] = [0u16; ADC_BUF_SIZE]).unwrap();
 
     let adc = Adc::new(p.ADC1);
+    let adc2 = Adc::new(p.ADC2);
 
     let mut adc: RingBufferedAdc<embassy_stm32::peripherals::ADC1> = adc.into_ring_buffered(p.DMA2_CH0, adc_data);
+    let mut adc2: RingBufferedAdc<embassy_stm32::peripherals::ADC2> = adc2.into_ring_buffered(p.DMA2_CH2, adc_data2);
 
     adc.set_sample_sequence(Sequence::One, &mut p.PA0, SampleTime::CYCLES112);
     adc.set_sample_sequence(Sequence::Two, &mut p.PA2, SampleTime::CYCLES112);
-    adc.set_sample_sequence(Sequence::Three, &mut p.PA1, SampleTime::CYCLES112);
+    adc2.set_sample_sequence(Sequence::One, &mut p.PA1, SampleTime::CYCLES112);
-    adc.set_sample_sequence(Sequence::Four, &mut p.PA3, SampleTime::CYCLES112);
+    adc2.set_sample_sequence(Sequence::Two, &mut p.PA3, SampleTime::CYCLES112);
 
     // Note that overrun is a big consideration in this implementation. Whatever task is running the adc.read() calls absolutely must circle back around
     // to the adc.read() call before the DMA buffer is wrapped around > 1 time. At this point, the overrun is so significant that the context of
@@ -31,10 +34,12 @@ async fn main(_spawner: Spawner) {
     // An interrupt executor with a higher priority than other tasks may be a good approach here, allowing this task to wake and read the buffer most
     // frequently.
     let mut tic = Instant::now();
-    let mut buffer1: [u16; 256] = [0u16; 256];
+    let mut buffer1 = [0u16; 256];
+    let mut buffer2 = [0u16; 256];
     let _ = adc.start();
+    let _ = adc2.start();
     loop {
-        match adc.read(&mut buffer1).await {
+        match adc.read_exact(&mut buffer1).await {
             Ok(_data) => {
                 let toc = Instant::now();
                 info!(
@@ -49,10 +54,25 @@ async fn main(_spawner: Spawner) {
                 warn!("Error: {:?}", e);
                 buffer1 = [0u16; 256];
                 let _ = adc.start();
-                continue;
             }
         }
 
-        Timer::after_micros(300).await;
+        match adc2.read_exact(&mut buffer2).await {
+            Ok(_data) => {
+                let toc = Instant::now();
+                info!(
+                    "\n adc2: {} dt = {}, n = {}",
+                    buffer2[0..16],
+                    (toc - tic).as_micros(),
+                    _data
+                );
+                tic = toc;
+            }
+            Err(e) => {
+                warn!("Error: {:?}", e);
+                buffer2 = [0u16; 256];
+                let _ = adc2.start();
+            }
+        }
     }
 }