Files
upm/src/buzzer/buzzer.h
2020-03-05 15:13:36 -08:00

104 lines
2.5 KiB
C

/*
* Author: Jon Trulson <jtrulson@ics.com>
* Copyright (c) 2016 Intel Corporation.
*
* based on original C++ driver by
* Author: Yevgeniy Kiveisha <yevgeniy.kiveisha@intel.com>
* Copyright (c) 2014 Intel Corporation.
*
* This program and the accompanying materials are made available under the
* terms of the The MIT License which is available at
* https://opensource.org/licenses/MIT.
*
* SPDX-License-Identifier: MIT
*/
#pragma once
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <upm.h>
#include <mraa/pwm.h>
#include "buzzer_tones.h"
#ifdef __cplusplus
extern "C" {
#endif
/**
* @file buzzer.h
* @library buzzer
* @brief C API for the buzzer driver
*
* @include buzzer.c
*/
/**
* Device context
*/
typedef struct _buzzer_context {
mraa_pwm_context pwm;
float volume;
bool initialized;
} *buzzer_context;
/**
* Initialize a buzzer context.
*
* @param pin Buzzer pin number (pwm capable)
* @return buzzer device context
*/
buzzer_context buzzer_init(int pin);
/**
* Buzzer object destructor.
*
* @param dev Device context.
*/
void buzzer_close(buzzer_context dev);
/**
* Plays a tone for a certain amount of time or indefinitely. When delay
* is not used, the sound can be stopped by calling stopSound().
*
* @param dev Device context.
* @param note Note to play (DO, RE, MI, etc.) or frequency
* @param delay Time in microseconds for which to play the sound;
* if the value is 0, the sound is played indefinitely
* @return UPM result
*/
upm_result_t buzzer_play_sound(const buzzer_context dev, int note,
int delay);
/**
* Stops the sound currently playing. Should be called when playSound()
* does not have a delay value.
*
* @param dev Device context.
* @return UPM result
*/
upm_result_t buzzer_stop_sound(const buzzer_context dev);
/**
* Sets the volume for the buzzer, but may affect the sound timbre.
* Works best with halved values; e.g., 1.0, 0.5, 0.25, etc.
*
* @param dev Device context.
* @param vol Value to set the volume to, from 0.0 to 1.0
*/
void buzzer_set_volume(const buzzer_context dev, float vol);
/**
* Gets the buzzer volume.
*
* @param dev Device context.
* @return Value the volume was set to
*/
float buzzer_get_volume(const buzzer_context dev);
#ifdef __cplusplus
}
#endif