uart rx working fully

semestralka_1d_rx_bez_dma/src/bin/main.rs

@@ -26,6 +26,8 @@ use dma_gpio::config::{PIPE_HW_TX, PIPE_HW_RX, PIPE_SW_TX, PIPE_SW_RX};
 use embassy_sync::{blocking_mutex::raw::CriticalSectionRawMutex, pipe::Pipe};
 use dma_gpio::hw_uart_internal::usart2;
 use dma_gpio::hw_uart_internal::driver::uart_task as uart_task_internal;
+use dma_gpio::software_uart::decode_uart_samples;
+use dma_gpio::config::UART_CFG;
 use dma_gpio::config::{PIPE_INT_TX, PIPE_INT_RX};
 use embassy_time::{Duration, Timer};
 use embassy_stm32::pac;
@@ -120,13 +122,44 @@ async fn main(spawner: Spawner) {
     // EDN OF SOFTWARE UART
 
     unsafe { cortex_m::peripheral::NVIC::unmask(pac::Interrupt::TIM7); }
-    let mut last_bit: Option<u8> = None;
+
+    let mut rx_samples = [1u8; 1024];
+    let mut rx_count = 0usize;
     loop {
+        // 1. Drain the channel into the local buffer
         while let Ok(bit) = PD6_BITS.try_receive() {
-            if Some(bit) != last_bit {
-                // PD6 level changed since the last sample → print one 'c'
-                info!("c");
-                last_bit = Some(bit);
+            if rx_count < rx_samples.len() {
+                rx_samples[rx_count] = bit;
+                rx_count += 1;
+            } else {
+                // Buffer full: discarding oldest data by rotating
+                // Simple naive strategy: just clear half
+                // Ideally we should prevent this by processing faster
+                warn!("RX Buffer overflow, resetting");
+                rx_count = 0;
+            }
+        }
+
+        // 2. Try to decode UART frames from the buffer
+        if rx_count > 0 {
+            // Try to decode
+            let (decoded, consumed) = decode_uart_samples(
+                &rx_samples[..rx_count], 
+                RX_OVERSAMPLE, 
+                &UART_CFG
+            );
+
+            // Print received characters
+            for b in decoded {
+                info!("Received: {}", b as char);
+            }
+
+            // 3. Remove processed samples from the buffer
+            if consumed > 0 {
+                // Shift remaining data to the front
+                // copy_within is efficient for slices
+                rx_samples.copy_within(consumed..rx_count, 0);
+                rx_count -= consumed;
             }
         }
         yield_now().await;

semestralka_1d_rx_bez_dma/src/software_uart/gpio_dma_uart_rx.rs

@@ -69,10 +69,10 @@ pub async fn rx_dma_task(
             levels[i] = ((*b >> RX_PIN_BIT) & 1) as u8;
         }
 
-        let decoded = decode_uart_samples(&levels, RX_OVERSAMPLE, &UART_CFG);
+        let (decoded, consumed) = decode_uart_samples(&levels, RX_OVERSAMPLE, &UART_CFG);
         if !decoded.is_empty() {
             info!("SW RX decoded {:a}", decoded.as_slice());
-            pipe_rx.write(&decoded).await;
+            pipe_rx.write(decoded.as_slice()).await;
         }
 
         yield_now().await;

semestralka_1d_rx_bez_dma/src/software_uart/runtime.rs

@@ -0,0 +1,81 @@
+// src/software_uart/runtime.rs
+use embassy_executor::task;
+use embassy_stm32::{
+    dma::Request,
+    peripherals::GPDMA1_CH1,
+    Peri,
+};
+use crate::config::RX_PIN_BIT;
+use embassy_stm32::dma::{
+    ReadableRingBuffer,
+    TransferOptions,
+};
+use crate::config::{RX_OVERSAMPLE, UART_CFG};
+use crate::software_uart::decode_uart_samples;
+use embassy_sync::{blocking_mutex::raw::CriticalSectionRawMutex, pipe::Pipe};
+use embassy_futures::yield_now;
+use defmt::info;
+
+// datasheet tabulka 137
+pub const TIM7_UP_REQ: Request = 5;
+
+/// RX DMA task: reads GPIO samples paced by TIM7 and fills PIPE_RX
+#[task]
+pub async fn rx_dma_task(
+    ch: Peri<'static, GPDMA1_CH1>,
+    register: *mut u8,
+    ring: &'static mut [u8],
+    pipe_rx: &'static Pipe<CriticalSectionRawMutex, 1024>,
+) {
+    let mut opts = TransferOptions::default();
+    opts.half_transfer_ir = true;
+    opts.complete_transfer_ir = true;
+
+    // SAFETY: ring is exclusive to this task
+    let mut rx = unsafe { ReadableRingBuffer::new(ch, TIM7_UP_REQ, register, ring, opts) };
+    rx.start();
+
+    let mut raw_chunk = [0u8; 256];
+    let mut levels = [0u8; 256];
+    let mut last_bytes: [u8; 16] = [0; 16];   // remember previous 16 samples
+    let mut last_value: u8 = 0;              // remember previous single IDR sample (optional)
+
+    loop {
+        let _ = rx.read_exact(&mut raw_chunk).await;
+
+        // If nothing has changed (all bytes same as previous), skip logging
+        if raw_chunk[..16] == last_bytes[..] {
+            continue;
+        }
+
+        // Save for next comparison
+        last_bytes.copy_from_slice(&raw_chunk[..16]);
+        let current_avg = raw_chunk[0];
+
+        // Optionally only if single sample changed
+        if current_avg != last_value {
+            last_value = current_avg;
+
+            info!(
+                "DMA change detected: IDR[0..16]={=[u8]:02X} bit{}={}",
+                &raw_chunk[..16],
+                RX_PIN_BIT,
+                (current_avg >> RX_PIN_BIT) & 1
+            );
+        }
+
+        // Extract logic levels as before
+        for (i, b) in raw_chunk.iter().enumerate() {
+            levels[i] = ((*b >> RX_PIN_BIT) & 1) as u8;
+        }
+
+        // Updated to handle tuple return (bytes, consumed_count)
+        let (decoded, _consumed) = decode_uart_samples(&levels, RX_OVERSAMPLE, &UART_CFG);
+        if !decoded.is_empty() {
+            info!("SW RX decoded {:a}", decoded.as_slice());
+            pipe_rx.write(&decoded).await;
+        }
+
+        yield_now().await;
+    }
+}

semestralka_1d_rx_bez_dma/src/software_uart/uart_emulation.rs

@@ -91,61 +91,82 @@ pub fn encode_uart_byte_cfg(
 }
 
 /// Decode an oversampled stream of logic levels into UART bytes.
+/// Returns (decoded bytes, number of samples consumed/processed).
 pub fn decode_uart_samples(
     samples: &[u8],
     oversample: u16,
     cfg: &UartConfig,
-) -> heapless::Vec<u8, 256> {
-
+) -> (heapless::Vec<u8, 256>, usize) {
     let mut out = Vec::<u8, 256>::new();
     let mut idx = 0usize;
     let nbits = cfg.data_bits as usize;
+    let ovs = oversample as usize;
 
-    while idx + (oversample as usize * (nbits + 3)) < samples.len() {
-        // Wait for start bit (falling edge: high -> low)
+    // Calculate total frame width in samples to ensure we have enough data
+    // 1 start + n data + parity? + stops
+    let parity_bits = match cfg.parity {
+        Parity::None => 0,
+        _ => 1,
+    };
+    let stop_bits_count = match cfg.stop_bits {
+        StopBits::One => 1,
+        StopBits::Two => 2,
+    };
+    let frame_bits = 1 + nbits + parity_bits + stop_bits_count;
+    let frame_len = frame_bits * ovs;
+
+    // We loop while we have enough remaining samples for a full frame
+    while idx + frame_len <= samples.len() {
+        // Wait for falling edge (High -> Low)
+        // samples[idx] == 1 (Idle/Stop) && samples[idx+1] == 0 (Start)
         if samples[idx] != 0 && samples[idx + 1] == 0 {
-            // Align to middle of start bit
-            idx += (oversample / 2) as usize;
+            
+            // Align to center of START bit
+            // Start bit begins at idx+1. Center is at idx + 1 + (ovs/2)
+            let center_offset = 1 + (ovs / 2);
+            let mut scan_idx = idx + center_offset;
 
-            // Sanity check start bit really low
-            if samples.get(idx).copied().unwrap_or(1) != 0 {
+            // Sanity check: is the middle of the start bit actually 0?
+            if samples.get(scan_idx).copied().unwrap_or(1) != 0 {
                 idx += 1;
                 continue;
             }
 
+            // Move to center of first data bit
+            scan_idx += ovs;
+
             // Sample data bits
             let mut data: u8 = 0;
             for bit in 0..nbits {
-                idx += oversample as usize;
                 let bit_val = samples
-                    .get(idx)
+                    .get(scan_idx)
                     .map(|&b| if b != 0 { 1u8 } else { 0u8 })
-                    .unwrap_or(1);
+                    .unwrap_or(1); // Default to high if out of bounds (shouldn't happen)
                 data |= bit_val << bit;
+                scan_idx += ovs;
             }
 
-            // Parity: skip / verify
+            // Parity: skip
             match cfg.parity {
                 Parity::None => {}
                 Parity::Even | Parity::Odd => {
-                    idx += oversample as usize;
-                    // You can optionally add parity check here if needed
+                    scan_idx += ovs;
                 }
             }
 
-            // Move past stop bits
-            let stop_skip = match cfg.stop_bits {
-                StopBits::One => oversample as usize,
-                StopBits::Two => (oversample * 2) as usize,
-            };
-            idx += stop_skip;
-
-            // Push decoded byte
+            // We successfully read a byte. 
+            // Advance main `idx` past this frame.
+            // We processed `frame_len` samples starting from `idx` (which was the idle bit before start).
+            // Actually, to be precise, we should advance by roughly the frame length.
+            idx += frame_len;
+            
+            // If overflow happens in push (unlikely given 256 limit), ignore
             let _ = out.push(data);
         } else {
+            // No start bit detected here, move to next sample
             idx += 1;
         }
     }
 
-    out
+    (out, idx)
 }