btstack/example/sine_player.c
2022-06-23 20:56:29 +02:00

99 lines
3.9 KiB
C

/*
* Copyright (C) 2014 BlueKitchen GmbH
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the copyright holders nor the names of
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
* 4. Any redistribution, use, or modification is done solely for
* personal benefit and not for any commercial purpose or for
* monetary gain.
*
* THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN
* GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
* THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* Please inquire about commercial licensing options at
* contact@bluekitchen-gmbh.com
*
*/
#define BTSTACK_FILE__ "sine_player.c"
/* EXAMPLE_START(audio_duplex): Audio Driver - Play Sine
*
* @text Play sine to test and validate audio output with simple wave form.
*/
#include "btstack.h"
#include <stdio.h>
#define TABLE_SIZE_441HZ 100
// change to 1 for mono output
#define NUM_CHANNELS 2
static int sine_phase;
static const int16_t sine_int16[] = {
0, 2057, 4107, 6140, 8149, 10126, 12062, 13952, 15786, 17557,
19260, 20886, 22431, 23886, 25247, 26509, 27666, 28714, 29648, 30466,
31163, 31738, 32187, 32509, 32702, 32767, 32702, 32509, 32187, 31738,
31163, 30466, 29648, 28714, 27666, 26509, 25247, 23886, 22431, 20886,
19260, 17557, 15786, 13952, 12062, 10126, 8149, 6140, 4107, 2057,
0, -2057, -4107, -6140, -8149, -10126, -12062, -13952, -15786, -17557,
-19260, -20886, -22431, -23886, -25247, -26509, -27666, -28714, -29648, -30466,
-31163, -31738, -32187, -32509, -32702, -32767, -32702, -32509, -32187, -31738,
-31163, -30466, -29648, -28714, -27666, -26509, -25247, -23886, -22431, -20886,
-19260, -17557, -15786, -13952, -12062, -10126, -8149, -6140, -4107, -2057,
};
static void audio_playback(int16_t * pcm_buffer, uint16_t num_samples_to_write){
int count;
for (count = 0; count < num_samples_to_write ; count++){
unsigned int channel;
for (channel = 0; channel < NUM_CHANNELS ; channel++){
pcm_buffer[count * NUM_CHANNELS + channel] = sine_int16[sine_phase];
}
sine_phase++;
if (sine_phase >= TABLE_SIZE_441HZ){
sine_phase -= TABLE_SIZE_441HZ;
}
}
}
int btstack_main(int argc, const char * argv[]);
int btstack_main(int argc, const char * argv[]){
(void)argc;
(void)argv;
// setup audio playback
const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
if (!audio){
printf("BTstack Audio Sink not setup\n");
return 10;
}
audio->init(NUM_CHANNELS, 44100, &audio_playback);
audio->start_stream();
return 0;
}
/* EXAMPLE_END */