nrz and nrzi are working right now

2sem_sem2/src/bin/main.rs

@@ -16,7 +16,7 @@ use semestralka2::send::{bit_send, nrz};
 
 use {defmt_rtt as _, panic_probe as _};
 
-static PIPE: Channel<CriticalSectionRawMutex, u8, 128> = Channel::new();
+static PIPE_SEND: Channel<CriticalSectionRawMutex, u8, 128> = Channel::new();
 static PIPE_REC: Channel<CriticalSectionRawMutex, u8, 128> = Channel::new();
 // static REC_ALLOWED: AtomicBool = AtomicBool::new(true);
 
@@ -28,11 +28,12 @@ async fn main(spawner: Spawner) {
     let tx = Output::new(p.PF2, gpio::Level::High, gpio::Speed::VeryHigh);
     let rx = ExtiInput::new(p.PA3, p.EXTI3, Pull::Up);
 
-    let sender = PIPE.sender();
+    let sender = PIPE_SEND.sender();
-    let receiver = PIPE.receiver();
+    let receiver = PIPE_SEND.receiver();
 
-    spawner.spawn(bit_send(tx, receiver)).unwrap();
+    let e_nrz = semestralka2::Encoding::Nrz;
-    spawner.spawn(bit_receive_and_decode(rx)).unwrap();
+    spawner.spawn(bit_send(tx, receiver, e_nrz)).unwrap();
+    spawner.spawn(bit_receive_and_decode(rx, e_nrz)).unwrap();
 
     info!("starting loop");
     loop {

2sem_sem2/src/lib.rs

@@ -2,3 +2,9 @@
 
 pub mod receive;
 pub mod send;
+
+#[derive(Copy, Clone, PartialEq)]
+pub enum Encoding {
+    Nrz,
+    Nrzi,
+}

2sem_sem2/src/receive.rs

@@ -1,6 +1,8 @@
 use defmt::info;
-use embassy_stm32::exti::ExtiInput;
+use embassy_stm32::{exti::ExtiInput, sai::FrameSyncDefinition};
-use embassy_time::{Duration, Timer};
+use embassy_time::{Ticker, Timer};
+
+use crate::Encoding;
 
 const START: u8 = 0x7E;
 const STOP: u8 = 0x81;
@@ -18,32 +20,73 @@ fn crc8(crc: u8, byte: u8) -> u8 {
     c
 }
 
-async fn sample_byte(pin: &mut ExtiInput<'static>, bit_time: Duration) -> u8 {
+async fn sample_byte(
+    pin: &mut ExtiInput<'static>,
+    encoding: Encoding,
+    ticker: &mut Ticker,
+    last_physical_level: &mut bool,
+) -> u8 {
     let mut byte = 0u8;
     for _ in 0..8 {
-        let bit = if pin.is_high() { 1 } else { 0 };
+        let current_level = pin.is_high();
+
+        let bit = match encoding {
+            Encoding::Nrz => {
+                if pin.is_high() {
+                    1
+                } else {
+                    0
+                }
+            }
+            Encoding::Nrzi => {
+                let bit = if current_level != *last_physical_level {
+                    1
+                } else {
+                    0
+                };
+                *last_physical_level = current_level;
+                bit
+            }
+        };
         byte = (byte << 1) | bit;
-        Timer::after(bit_time).await;
+        ticker.next().await;
     }
     byte
 }
 
 #[embassy_executor::task]
-pub async fn bit_receive_and_decode(mut pin: ExtiInput<'static>) {
+pub async fn bit_receive_and_decode(mut pin: ExtiInput<'static>, encoding: Encoding) {
     loop {
         pin.wait_for_falling_edge().await;
-
         let t1 = embassy_time::Instant::now();
 
         pin.wait_for_rising_edge().await;
         let bit_time = embassy_time::Instant::now().duration_since(t1);
 
         Timer::after(bit_time / 2).await;
+        let mut ticker = Ticker::every(bit_time);
+
+        let mut last_level = true;
+
         let mut start_byte = 0u8;
         for _ in 0..7 {
-            let bit = if pin.is_high() { 1 } else { 0 };
+            let current_level = pin.is_high();
+            let bit = match encoding {
+                Encoding::Nrz => {
+                    if pin.is_high() {
+                        1
+                    } else {
+                        0
+                    }
+                }
+                Encoding::Nrzi => {
+                    let b = if current_level != last_level { 1 } else { 0 };
+                    last_level = current_level;
+                    b
+                }
+            };
             start_byte = (start_byte << 1) | bit;
-            Timer::after(bit_time).await;
+            ticker.next().await;
         }
 
         if start_byte != START {
@@ -52,7 +95,7 @@ pub async fn bit_receive_and_decode(mut pin: ExtiInput<'static>) {
         }
 
         // len
-        let len = sample_byte(&mut pin, bit_time).await;
+        let len = sample_byte(&mut pin, encoding, &mut ticker, &mut last_level).await;
         if len as usize > MAX_PAYLOAD {
             info!("bad len {}", len);
             continue;
@@ -61,18 +104,32 @@ pub async fn bit_receive_and_decode(mut pin: ExtiInput<'static>) {
         // payload
         let mut payload = [0u8; MAX_PAYLOAD];
         for i in 0..(len as usize) {
-            payload[i] = sample_byte(&mut pin, bit_time).await;
+            payload[i] = sample_byte(&mut pin, encoding, &mut ticker, &mut last_level).await;
         }
 
         // crc
-        let crc_recv = sample_byte(&mut pin, bit_time).await;
+        let crc_recv = sample_byte(&mut pin, encoding, &mut ticker, &mut last_level).await;
 
         // parita
-        let parity_recv = if pin.is_high() { 1 } else { 0 };
+        let current_p = pin.is_high();
-        Timer::after(bit_time).await;
+        let parity_recv = match encoding {
+            Encoding::Nrz => {
+                if current_p {
+                    1
+                } else {
+                    0
+                }
+            }
+            Encoding::Nrzi => {
+                let b = if current_p != last_level { 1 } else { 0 };
+                last_level = current_p;
+                b
+            }
+        };
+        ticker.next().await;
 
         // stop
-        let stop = sample_byte(&mut pin, bit_time).await;
+        let stop = sample_byte(&mut pin, encoding, &mut ticker, &mut last_level).await;
         if stop != STOP {
             info!("bad stop 0x{:02X}", stop);
             continue;

2sem_sem2/src/send.rs

@@ -7,6 +7,8 @@ use embassy_sync::{
 };
 use embassy_time::{Duration, Ticker};
 
+use crate::Encoding;
+
 const START: u8 = 0x7E;
 const STOP: u8 = 0x81;
 const BIT_PERIOD: Duration = Duration::from_millis(10);
@@ -66,15 +68,37 @@ fn crc8(crc: u8, byte: u8) -> u8 {
 pub async fn bit_send(
     mut pin: Output<'static>,
     rx: Receiver<'static, CriticalSectionRawMutex, u8, 128>,
+    encoding: Encoding,
 ) {
     let mut ticker = Ticker::every(BIT_PERIOD);
+    let mut is_high = true;
+    pin.set_high();
+
     loop {
         let bit = rx.receive().await;
+        match encoding {
+            Encoding::Nrz => {
                 if bit == 1 {
+                    is_high = true;
+                    pin.set_high();
+                } else {
+                    is_high = false;
+                    pin.set_low();
+                }
+            }
+            // toggle, ak sme v 1, inac sa nedeje nic
+            Encoding::Nrzi => {
+                if bit == 1 {
+                    is_high = !is_high;
+                    if is_high {
                         pin.set_high();
                     } else {
                         pin.set_low();
                     }
+                }
+            }
+        };
+
         // bitrate
         ticker.next().await;
     }