Merge #736

736: More `xtasks` and add examples to `rtic` repo r=korken89 a=datdenkikniet

This was in #732 before, but decluttering that PR seemed sensible

Co-authored-by: datdenkikniet <jcdra1@gmail.com>

1 files changed, 115 insertions, 0 deletions

diff --git a/examples/rp2040_local_i2c_init/src/main.rs b/examples/rp2040_local_i2c_init/src/main.rs
new file mode 100644
index 0000000..6776892
--- /dev/null
+++ b/examples/rp2040_local_i2c_init/src/main.rs
@@ -0,0 +1,115 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+#[rtic::app(
+    device = rp_pico::hal::pac,
+    dispatchers = [TIMER_IRQ_1]
+)]
+mod app {
+    use rp_pico::hal::{
+        clocks, gpio,
+        gpio::pin::bank0::{Gpio2, Gpio25, Gpio3},
+        gpio::pin::PushPullOutput,
+        pac,
+        sio::Sio,
+        watchdog::Watchdog,
+        I2C,
+    };
+    use rp_pico::XOSC_CRYSTAL_FREQ;
+
+    use core::mem::MaybeUninit;
+    use embedded_hal::digital::v2::{OutputPin, ToggleableOutputPin};
+    use fugit::RateExtU32;
+    use rtic_monotonics::rp2040::*;
+
+    use panic_probe as _;
+
+    type I2CBus = I2C<
+        pac::I2C1,
+        (
+            gpio::Pin<Gpio2, gpio::FunctionI2C>,
+            gpio::Pin<Gpio3, gpio::FunctionI2C>,
+        ),
+    >;
+
+    #[shared]
+    struct Shared {}
+
+    #[local]
+    struct Local {
+        led: gpio::Pin<Gpio25, PushPullOutput>,
+        i2c: &'static mut I2CBus,
+    }
+
+    #[init(local=[
+        // Task local initialized resources are static
+        // Here we use MaybeUninit to allow for initialization in init()
+        // This enables its usage in driver initialization
+        i2c_ctx: MaybeUninit<I2CBus> = MaybeUninit::uninit()
+    ])]
+    fn init(mut ctx: init::Context) -> (Shared, Local) {
+        // Initialize the interrupt for the RP2040 timer and obtain the token
+        // proving that we have.
+        let rp2040_timer_token = rtic_monotonics::create_rp2040_monotonic_token!();
+        // Configure the clocks, watchdog - The default is to generate a 125 MHz system clock
+        Timer::start(ctx.device.TIMER, &mut ctx.device.RESETS, rp2040_timer_token); // default rp2040 clock-rate is 125MHz
+        let mut watchdog = Watchdog::new(ctx.device.WATCHDOG);
+        let clocks = clocks::init_clocks_and_plls(
+            XOSC_CRYSTAL_FREQ,
+            ctx.device.XOSC,
+            ctx.device.CLOCKS,
+            ctx.device.PLL_SYS,
+            ctx.device.PLL_USB,
+            &mut ctx.device.RESETS,
+            &mut watchdog,
+        )
+        .ok()
+        .unwrap();
+
+        // Init LED pin
+        let sio = Sio::new(ctx.device.SIO);
+        let gpioa = rp_pico::Pins::new(
+            ctx.device.IO_BANK0,
+            ctx.device.PADS_BANK0,
+            sio.gpio_bank0,
+            &mut ctx.device.RESETS,
+        );
+        let mut led = gpioa.led.into_push_pull_output();
+        led.set_low().unwrap();
+
+        // Init I2C pins
+        let sda_pin = gpioa.gpio2.into_mode::<gpio::FunctionI2C>();
+        let scl_pin = gpioa.gpio3.into_mode::<gpio::FunctionI2C>();
+
+        // Init I2C itself, using MaybeUninit to overwrite the previously
+        // uninitialized i2c_ctx variable without dropping its value
+        // (i2c_ctx definined in init local resources above)
+        let i2c_tmp: &'static mut _ = ctx.local.i2c_ctx.write(I2C::i2c1(
+            ctx.device.I2C1,
+            sda_pin,
+            scl_pin,
+            100.kHz(),
+            &mut ctx.device.RESETS,
+            &clocks.system_clock,
+        ));
+
+        // Spawn heartbeat task
+        heartbeat::spawn().ok();
+
+        // Return resources and timer
+        (Shared {}, Local { led, i2c: i2c_tmp })
+    }
+
+    #[task(local = [i2c, led])]
+    async fn heartbeat(ctx: heartbeat::Context) {
+        // Flicker the built-in LED
+        _ = ctx.local.led.toggle();
+
+        // Congrats, you can use your i2c and have access to it here,
+        // now to do something with it!
+
+        // Re-spawn this task after 1 second
+        Timer::delay(1000.millis()).await;
+    }
+}