/* Audio Library for Teensy 3.X * Copyright (c) 2014, Paul Stoffregen, paul@pjrc.com * * Development of this audio library was funded by PJRC.COM, LLC by sales of * Teensy and Audio Adaptor boards. Please support PJRC's efforts to develop * open source software by purchasing Teensy or other PJRC products. * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice, development funding notice, and this permission * notice shall be included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ #include "Audio.h" #include "arm_math.h" // data_waveforms.c extern "C" { extern const int16_t AudioWaveformSine[257]; } void AudioSynthWaveformSine::frequency(float f) { if (f > AUDIO_SAMPLE_RATE_EXACT / 2 || f < 0.0) return; phase_increment = (f / AUDIO_SAMPLE_RATE_EXACT) * 4294967296.0f; } void AudioSynthWaveformSine::update(void) { audio_block_t *block; uint32_t i, ph, inc, index, scale; int32_t val1, val2; //Serial.println("AudioSynthWaveformSine::update"); block = allocate(); if (block) { ph = phase; inc = phase_increment; for (i=0; i < AUDIO_BLOCK_SAMPLES; i++) { index = ph >> 24; val1 = AudioWaveformSine[index]; val2 = AudioWaveformSine[index+1]; scale = (ph >> 8) & 0xFFFF; val2 *= scale; val1 *= 0xFFFF - scale; block->data[i] = (val1 + val2) >> 16; //Serial.print(block->data[i]); //Serial.print(", "); //if ((i % 12) == 11) Serial.println(); ph += inc; } //Serial.println(); phase = ph; transmit(block); release(block); return; } phase += phase_increment * AUDIO_BLOCK_SAMPLES; } void AudioSynthWaveformSineModulated::frequency(float f) { if (f > AUDIO_SAMPLE_RATE_EXACT / 2 || f < 0.0) return; phase_increment = (f / AUDIO_SAMPLE_RATE_EXACT) * 4294967296.0f; } void AudioSynthWaveformSineModulated::update(void) { audio_block_t *block, *modinput; uint32_t i, ph, inc, index, scale; int32_t val1, val2; //Serial.println("AudioSynthWaveformSineModulated::update"); modinput = receiveReadOnly(); ph = phase; inc = phase_increment; block = allocate(); if (!block) { // unable to allocate memory, so we'll send nothing if (modinput) { // but if we got modulation data, update the phase for (i=0; i < AUDIO_BLOCK_SAMPLES; i++) { ph += inc + modinput->data[i] * modulation_factor; } release(modinput); } else { ph += phase_increment * AUDIO_BLOCK_SAMPLES; } phase = ph; return; } if (modinput) { for (i=0; i < AUDIO_BLOCK_SAMPLES; i++) { index = ph >> 24; val1 = AudioWaveformSine[index]; val2 = AudioWaveformSine[index+1]; scale = (ph >> 8) & 0xFFFF; val2 *= scale; val1 *= 0xFFFF - scale; block->data[i] = (val1 + val2) >> 16; //Serial.print(block->data[i]); //Serial.print(", "); //if ((i % 12) == 11) Serial.println(); ph += inc + modinput->data[i] * modulation_factor; } release(modinput); } else { ph = phase; inc = phase_increment; for (i=0; i < AUDIO_BLOCK_SAMPLES; i++) { index = ph >> 24; val1 = AudioWaveformSine[index]; val2 = AudioWaveformSine[index+1]; scale = (ph >> 8) & 0xFFFF; val2 *= scale; val1 *= 0xFFFF - scale; block->data[i] = (val1 + val2) >> 16; //Serial.print(block->data[i]); //Serial.print(", "); //if ((i % 12) == 11) Serial.println(); ph += inc; } } phase = ph; transmit(block); release(block); }