#![no_main]
#![no_std]
extern crate panic_halt;

use cortex_m_rt::entry;
use hal::{pac, prelude::*, rcc::Config};

#[entry]
fn main() -> ! {
    // get access to the peripherals
    let dp = pac::Peripherals::take().unwrap();
    let cp = cortex_m::Peripherals::take().unwrap();

    // configure the clock
    let mut rcc = dp.RCC.freeze(Config::hsi16());

    // get access to GPIO Port A
    let gpioa = dp.GPIOA.split(&mut rcc);

    // configure Pin 5 og GPIO Port A as output
    let mut led = gpioa.pa5.into_push_pull_output();

    // prepare delays (sleeping)
    let mut delay = cp.SYST.delay(rcc.clocks);

    loop {
        led.set_high().unwrap(); // light on
        delay.delay_ms(500_u16); // wait

        led.set_low().unwrap(); // light off
        delay.delay_ms(500_u16); // wait
    }
}