esp-hal/esp32s2-hal/examples/blinky.rs

//! Blinks an LED
//!
//! This assumes that a LED is connected to the pin assigned to `led`. (GPIO4)

#![no_std]
#![no_main]

use esp32s2_hal::{
    clock::ClockControl,
    gpio::IO,
    peripherals::Peripherals,
    prelude::*,
    timer::TimerGroup,
    Delay,
    Rtc,
};
use esp_backtrace as _;
use xtensa_atomic_emulation_trap as _;
use xtensa_lx_rt::entry;

#[entry]
fn main() -> ! {
    let peripherals = Peripherals::take();
    let system = peripherals.SYSTEM.split();
    let clocks = ClockControl::boot_defaults(system.clock_control).freeze();

    let timer_group0 = TimerGroup::new(peripherals.TIMG0, &clocks);
    let mut wdt = timer_group0.wdt;
    let mut rtc = Rtc::new(peripherals.RTC_CNTL);

    // Disable MWDT and RWDT (Watchdog) flash boot protection
    wdt.disable();
    rtc.rwdt.disable();

    // Set GPIO4 as an output, and set its state high initially.
    let io = IO::new(peripherals.GPIO, peripherals.IO_MUX);
    let mut led = io.pins.gpio4.into_push_pull_output();

    led.set_high().unwrap();

    // Initialize the Delay peripheral, and use it to toggle the LED state in a
    // loop.
    let mut delay = Delay::new(&clocks);

    loop {
        led.toggle().unwrap();
        delay.delay_ms(500u32);
    }
}

#[xtensa_lx_rt::exception]
fn exception(
    cause: xtensa_lx_rt::exception::ExceptionCause,
    frame: xtensa_lx_rt::exception::Context,
) {
    use esp_println::*;

    println!("\n\nException occured {:?} {:x?}", cause, frame);

    let backtrace = esp_backtrace::arch::backtrace();
    for b in backtrace.iter() {
        if let Some(addr) = b {
            println!("0x{:x}", addr)
        }
    }
}