1 /*
2 * Copyright (C) 2014 BlueKitchen GmbH
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the copyright holders nor the names of
14 * contributors may be used to endorse or promote products derived
15 * from this software without specific prior written permission.
16 * 4. Any redistribution, use, or modification is done solely for
17 * personal benefit and not for any commercial purpose or for
18 * monetary gain.
19 *
20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN
24 * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 * Please inquire about commercial licensing options at
34 * [email protected]
35 *
36 */
37
38 #define BTSTACK_FILE__ "sine_player.c"
39
40 /* EXAMPLE_START(audio_duplex): Audio Driver - Play Sine
41 *
42 * @text Play sine to test and validate audio output with simple wave form.
43 */
44
45 #include "btstack.h"
46 #include <stdio.h>
47
48 #define TABLE_SIZE_441HZ 100
49
50 // change to 1 for mono output
51 #define NUM_CHANNELS 2
52
53 static int sine_phase;
54
55 static const int16_t sine_int16[] = {
56 0, 2057, 4107, 6140, 8149, 10126, 12062, 13952, 15786, 17557,
57 19260, 20886, 22431, 23886, 25247, 26509, 27666, 28714, 29648, 30466,
58 31163, 31738, 32187, 32509, 32702, 32767, 32702, 32509, 32187, 31738,
59 31163, 30466, 29648, 28714, 27666, 26509, 25247, 23886, 22431, 20886,
60 19260, 17557, 15786, 13952, 12062, 10126, 8149, 6140, 4107, 2057,
61 0, -2057, -4107, -6140, -8149, -10126, -12062, -13952, -15786, -17557,
62 -19260, -20886, -22431, -23886, -25247, -26509, -27666, -28714, -29648, -30466,
63 -31163, -31738, -32187, -32509, -32702, -32767, -32702, -32509, -32187, -31738,
64 -31163, -30466, -29648, -28714, -27666, -26509, -25247, -23886, -22431, -20886,
65 -19260, -17557, -15786, -13952, -12062, -10126, -8149, -6140, -4107, -2057,
66 };
67
audio_playback(int16_t * pcm_buffer,uint16_t num_samples_to_write)68 static void audio_playback(int16_t * pcm_buffer, uint16_t num_samples_to_write){
69 int count;
70 for (count = 0; count < num_samples_to_write ; count++){
71 unsigned int channel;
72 for (channel = 0; channel < NUM_CHANNELS ; channel++){
73 pcm_buffer[count * NUM_CHANNELS + channel] = sine_int16[sine_phase];
74 }
75 sine_phase++;
76 if (sine_phase >= TABLE_SIZE_441HZ){
77 sine_phase -= TABLE_SIZE_441HZ;
78 }
79 }
80 }
81
82 int btstack_main(int argc, const char * argv[]);
btstack_main(int argc,const char * argv[])83 int btstack_main(int argc, const char * argv[]){
84 (void)argc;
85 (void)argv;
86
87 // setup audio playback
88 const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
89 if (!audio){
90 printf("BTstack Audio Sink not setup\n");
91 return 10;
92 }
93 audio->init(NUM_CHANNELS, 44100, &audio_playback);
94 audio->start_stream();
95
96 return 0;
97 }
98
99 /* EXAMPLE_END */