/**
 * Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

// Output buzzer sound signal on specific pin.
#include "pico/stdlib.h"
#include "hardware/pwm.h"
#include "hardware/clocks.h"  

void buzzer_gpio_init(uint16_t gpio_pin){
	gpio_set_function(gpio_pin, GPIO_FUNC_PWM);
}

void buzzer_play(uint16_t gpio_pin, uint16_t frequency){
	uint16_t slice_num = pwm_gpio_to_slice_num(gpio_pin);
  pwm_config config = pwm_get_default_config();
	float div = (float)clock_get_hz(clk_sys) / (frequency * 9999);
	pwm_config_set_clkdiv(&config, div);
	pwm_config_set_wrap(&config, 10000); 
	pwm_init(slice_num, &config, true); // start the pwm running according to the config
	pwm_set_gpio_level(gpio_pin, 5000); //connect the pin to the pwm engine and set the on/off level.
}

void buzzer_stop( uint16_t gpio_pin ){

	uint16_t slice_num = pwm_gpio_to_slice_num(gpio_pin);
	// Set the PWM stop
  pwm_set_enabled(slice_num, false);
}

int main() {

    const uint16_t gpio_buzzer_pin = 16;

		buzzer_gpio_init(gpio_buzzer_pin);

    while (true){

			buzzer_play(gpio_buzzer_pin, 700);
			sleep_ms(500);
			buzzer_play(gpio_buzzer_pin, 560);
			sleep_ms(500);
			buzzer_play(gpio_buzzer_pin, 700);
			sleep_ms(500);
			buzzer_play(gpio_buzzer_pin, 560);
			sleep_ms(500);

			buzzer_stop(gpio_buzzer_pin);
			sleep_ms(2000);
    }
        
}