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 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[]); 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 */