CAN: Unify API's between BXCAN and FDCAN. Use Envelope for all read methods instead of a tuple sometimes.

2 files changed, 90 insertions, 13 deletions

diff --git a/examples/stm32f1/Cargo.toml b/examples/stm32f1/Cargo.toml
index df5d32f70..4f282f326 100644
--- a/examples/stm32f1/Cargo.toml
+++ b/examples/stm32f1/Cargo.toml
@@ -23,6 +23,7 @@ panic-probe = { version = "0.3", features = ["print-defmt"] }
 futures = { version = "0.3.17", default-features = false, features = ["async-await"] }
 heapless = { version = "0.8", default-features = false }
 nb = "1.0.0"
+static_cell = "2.0.0"
 
 [profile.dev]
 opt-level = "s"
diff --git a/examples/stm32f1/src/bin/can.rs b/examples/stm32f1/src/bin/can.rs
index ac337e8a0..90cb9e46b 100644
--- a/examples/stm32f1/src/bin/can.rs
+++ b/examples/stm32f1/src/bin/can.rs
@@ -4,11 +4,12 @@
 use defmt::*;
 use embassy_executor::Spawner;
 use embassy_stm32::can::{
-    filter, Can, Fifo, Frame, Id, Rx0InterruptHandler, Rx1InterruptHandler, SceInterruptHandler, StandardId,
+    filter, Can, Envelope, Fifo, Frame, Id, Rx0InterruptHandler, Rx1InterruptHandler, SceInterruptHandler, StandardId,
     TxInterruptHandler,
 };
 use embassy_stm32::peripherals::CAN;
 use embassy_stm32::{bind_interrupts, Config};
+use static_cell::StaticCell;
 use {defmt_rtt as _, panic_probe as _};
 
 bind_interrupts!(struct Irqs {
@@ -21,6 +22,27 @@ bind_interrupts!(struct Irqs {
 // This example is configured to work with real CAN transceivers on B8/B9.
 // See other examples for loopback.
 
+fn handle_frame(env: Envelope, read_mode: &str) {
+    match env.frame.id() {
+        Id::Extended(id) => {
+            defmt::println!(
+                "{} Extended Frame id={:x} {:02x}",
+                read_mode,
+                id.as_raw(),
+                env.frame.data()
+            );
+        }
+        Id::Standard(id) => {
+            defmt::println!(
+                "{} Standard Frame id={:x} {:02x}",
+                read_mode,
+                id.as_raw(),
+                env.frame.data()
+            );
+        }
+    }
+}
+
 #[embassy_executor::main]
 async fn main(_spawner: Spawner) {
     let p = embassy_stm32::init(Config::default());
@@ -28,6 +50,9 @@ async fn main(_spawner: Spawner) {
     // Set alternate pin mapping to B8/B9
     embassy_stm32::pac::AFIO.mapr().modify(|w| w.set_can1_remap(2));
 
+    static RX_BUF: StaticCell<embassy_stm32::can::RxBuf<10>> = StaticCell::new();
+    static TX_BUF: StaticCell<embassy_stm32::can::TxBuf<10>> = StaticCell::new();
+
     let mut can = Can::new(p.CAN, p.PB8, p.PB9, Irqs);
 
     can.as_mut()
@@ -43,21 +68,72 @@ async fn main(_spawner: Spawner) {
     can.set_bitrate(250_000);
 
     can.enable().await;
-
     let mut i: u8 = 0;
+
+    /*
+       // Example for using buffered Tx and Rx without needing to
+       // split first as is done below.
+       let mut can = can.buffered(
+           TX_BUF.init(embassy_stm32::can::TxBuf::<10>::new()),
+           RX_BUF.init(embassy_stm32::can::RxBuf::<10>::new()));
+       loop {
+           let tx_frame = Frame::new_data(unwrap!(StandardId::new(i as _)), &[i, 0, 1, 2, 3, 4, 5, 6]).unwrap();
+           can.write(&tx_frame).await;
+
+           match can.read().await {
+               Ok((frame, ts)) => {
+                   handle_frame(Envelope { ts, frame }, "Buf");
+               }
+               Err(err) => {
+                   defmt::println!("Error {}", err);
+               }
+           }
+           i += 1;
+       }
+
+    */
+    let (mut tx, mut rx) = can.split();
+
+    // This example shows using the wait_not_empty API before try read
+    while i < 3 {
+        let tx_frame = Frame::new_data(unwrap!(StandardId::new(i as _)), &[i, 0, 1, 2, 3, 4, 5, 6]).unwrap();
+        tx.write(&tx_frame).await;
+
+        rx.wait_not_empty().await;
+        let env = rx.try_read().unwrap();
+        handle_frame(env, "Wait");
+        i += 1;
+    }
+
+    // This example shows using the full async non-buffered API
+    while i < 6 {
+        let tx_frame = Frame::new_data(unwrap!(StandardId::new(i as _)), &[i, 0, 1, 2, 3, 4, 5, 6]).unwrap();
+        tx.write(&tx_frame).await;
+
+        match rx.read().await {
+            Ok(env) => {
+                handle_frame(env, "NoBuf");
+            }
+            Err(err) => {
+                defmt::println!("Error {}", err);
+            }
+        }
+        i += 1;
+    }
+
+    // This example shows using buffered RX and TX. User passes in desired buffer (size)
+    // It's possible this way to have just RX or TX buffered.
+    let mut rx = rx.buffered(RX_BUF.init(embassy_stm32::can::RxBuf::<10>::new()));
+    let mut tx = tx.buffered(TX_BUF.init(embassy_stm32::can::TxBuf::<10>::new()));
+
     loop {
         let tx_frame = Frame::new_data(unwrap!(StandardId::new(i as _)), &[i, 0, 1, 2, 3, 4, 5, 6]).unwrap();
-        can.write(&tx_frame).await;
-
-        match can.read().await {
-            Ok(env) => match env.frame.id() {
-                Id::Extended(id) => {
-                    defmt::println!("Extended Frame id={:x} {:02x}", id.as_raw(), env.frame.data());
-                }
-                Id::Standard(id) => {
-                    defmt::println!("Standard Frame id={:x} {:02x}", id.as_raw(), env.frame.data());
-                }
-            },
+        tx.write(&tx_frame).await;
+
+        match rx.read().await {
+            Ok(envelope) => {
+                handle_frame(envelope, "Buf");
+            }
             Err(err) => {
                 defmt::println!("Error {}", err);
             }