//! Uses timer0 and operator0 of the MCPWM0 peripheral to output a 50% duty
//! signal at 20 kHz.
//!
//! The following wiring is assumed:
//! - Output pin => GPIO0

//% CHIPS: esp32 esp32c6 esp32h2 esp32s3

#![no_std]
#![no_main]

use esp_backtrace as _;
use esp_hal::{
    clock::ClockControl,
    gpio::Io,
    mcpwm::{operator::PwmPinConfig, timer::PwmWorkingMode, McPwm, PeripheralClockConfig},
    peripherals::Peripherals,
    prelude::*,
    system::SystemControl,
};

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

    let io = Io::new(peripherals.GPIO, peripherals.IO_MUX);
    let pin = io.pins.gpio0;

    // initialize peripheral
    #[cfg(feature = "esp32h2")]
    let clock_cfg = PeripheralClockConfig::with_frequency(&clocks, 40.MHz()).unwrap();
    #[cfg(not(feature = "esp32h2"))]
    let clock_cfg = PeripheralClockConfig::with_frequency(&clocks, 32.MHz()).unwrap();

    let mut mcpwm = McPwm::new(peripherals.MCPWM0, clock_cfg);

    // connect operator0 to timer0
    mcpwm.operator0.set_timer(&mcpwm.timer0);
    // connect operator0 to pin
    let mut pwm_pin = mcpwm
        .operator0
        .with_pin_a(pin, PwmPinConfig::UP_ACTIVE_HIGH);

    // start timer with timestamp values in the range of 0..=99 and a frequency of
    // 20 kHz
    let timer_clock_cfg = clock_cfg
        .timer_clock_with_frequency(99, PwmWorkingMode::Increase, 20.kHz())
        .unwrap();
    mcpwm.timer0.start(timer_clock_cfg);

    // pin will be high 50% of the time
    pwm_pin.set_timestamp(50);

    loop {}
}
