add can driver

embassy-stm32f4-examples/Cargo.toml

@@ -31,3 +31,4 @@ panic-probe = "0.1.0"
 stm32f4xx-hal  = { version = "0.8.3", features = ["rt", "stm32f405"], git = "https://github.com/stm32-rs/stm32f4xx-hal.git"}
 futures = { version = "0.3.8", default-features = false, features = ["async-await"] }
 rtt-target = { version = "0.3", features = ["cortex-m"] }
+bxcan = "0.5.0"

embassy-stm32f4-examples/src/bin/can.rs

@@ -0,0 +1,64 @@
+#![no_std]
+#![no_main]
+#![feature(trait_alias)]
+#![feature(type_alias_impl_trait)]
+
+#[path = "../example_common.rs"]
+mod example_common;
+use example_common::{panic, *};
+
+use cortex_m_rt::entry;
+use embassy::executor::{task, Executor};
+use embassy::traits::gpio::*;
+use embassy::util::Forever;
+use embassy_stm32f4::can;
+use embassy_stm32f4::exti;
+use embassy_stm32f4::interrupt;
+use futures::pin_mut;
+use stm32f4xx_hal::prelude::*;
+use stm32f4xx_hal::stm32;
+
+static EXTI: Forever<exti::ExtiManager> = Forever::new();
+
+#[task]
+async fn run(dp: stm32::Peripherals, _cp: cortex_m::Peripherals) {
+    let rx = gpioa.pa11.into_alternate_af9();
+    let tx = gpioa.pa12.into_alternate_af9();
+    let mut can = bxcan::Can::new(Can::new(dp.CAN1, (tx, rx)));
+
+    // APB1 (PCLK1): 24MHz, Bit rate: 20kBit/s, Sample Point 87.5%
+    // Value was calculated with http://www.bittiming.can-wiki.info/
+    can.modify_config().set_bit_timing(0x001c_004a);
+    // Configure filters so that can frames can be received.
+    can.modify_filters().enable_bank(0, Mask32::accept_all());
+
+    block!(can.enable()).unwrap();
+
+    let can = can::Can::new(
+        can,
+        interrupt::take!(CAN1_TX),
+        interrupt::take!(CAN1_RX0),
+    ));
+
+    let frame = can.receive().await;
+}
+
+static EXECUTOR: Forever<Executor> = Forever::new();
+
+#[entry]
+fn main() -> ! {
+    let dp = stm32::Peripherals::take().unwrap();
+    let cp = cortex_m::peripheral::Peripherals::take().unwrap();
+
+    dp.DBGMCU.cr.modify(|_, w| {
+        w.dbg_sleep().set_bit();
+        w.dbg_standby().set_bit();
+        w.dbg_stop().set_bit()
+    });
+    dp.RCC.ahb1enr.modify(|_, w| w.dma1en().enabled());
+
+    let executor = EXECUTOR.put(Executor::new());
+    executor.run(|spawner| {
+        unwrap!(spawner.spawn(run(dp, cp)));
+    });
+}