/* * 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 #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 */