642b4973ca
Made it possible to select type and number of oscillators to compile (via preprocessor). Made Examples folder to library where tutorials will go in.
729 lines
15 KiB
C++
729 lines
15 KiB
C++
/*
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Music.cpp - Music library
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Copyright (c) 2012 Copenhagen Institute of Interaction Design.
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All right reserved.
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This library is free software: you can redistribute it and/or modify
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it under the terms of the GNU Lesser Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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This library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU Lesser Public License for more details.
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You should have received a copy of the GNU Lesser Public License
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along with Foobar. If not, see <http://www.gnu.org/licenses/>.
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+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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+ author: Jakob Bak
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+ contact: j.bak@ciid.dk
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*/
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#include "Music.h"
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#include "Wavetable.h"
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// Table of MIDI note values to frequency in Hertz
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prog_uint16_t hertsTable[] PROGMEM = {8,8,9,9,10,10,11,12,12,13,14,15,16,17,18,19,20,21,23,24,25,27,29,30,32,34,36,38,41,43,46,48,51,54,58,61,65,69,73,77,82,87,92,97,103,109,116,123,130,138,146,155,164,174,184,195,207,219,233,246,261,277,293,311,329,349,369,391,415,440,466,493,523,554,587,622,659,698,739,783,830,880,932,987,1046,1108,1174,1244,1318,1396,1479,1567,1661,1760,1864,1975,2093,2217,2349,2489,2637,2793,2959,3135,3322,3520,3729,3951,4186,4434,4698,4978,5274,5587,5919,6271,6644,7040,7458,7902,8372,8869,9397,9956,10548,11175,11839,12543};
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prog_uint32_t envTimeTable[] PROGMEM = {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,33,34,35,36,37,38,39,41,42,43,45,46,48,49,51,53,55,57,59,61,63,65,67,70,73,75,78,81,85,88,92,96,100,104,109,114,119,125,131,138,146,154,163,172,183,195,209,225,242,261,284,310,341,379,425,482,556,654,792,998,1342,2030,4095};
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float semitoneTable[] = {0.25,0.2648658,0.2806155,0.29730177,0.31498027,0.33370996,0.35355338,0.37457678,0.39685026,0.4204482,0.44544938,0.47193715,0.5,0.5297315,0.561231,0.59460354,0.62996054,0.6674199,0.70710677,0.74915355,0.7937005,0.8408964,0.8908987,0.9438743,1.0,1.0594631,1.122462,1.1892071,1.2599211,1.3348398,1.4142135,1.4983071,1.587401,1.6817929,1.7817974,1.8877486,2.0,2.1189263,2.244924,2.3784142,2.5198421,2.6696796,2.828427,2.9966142,3.174802,3.3635857,3.563595,3.7754972,4.0};
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MMusic Music;
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// Defining which pins the SPI interface is connected to.
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#define SPI_SCK 5
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#define SPI_MOSI 3
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// timer 2 is audio interrupt timer
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ISR(TIMER2_COMPA_vect) {
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OCR2A = 127;
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// Music.synthInterrupt8bit();
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Music.synthInterrupt12bitSine();
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}
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/////////////////////////////////////
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//
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// INITIALIZING FUNCTION
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//
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/////////////////////////////////////
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void MMusic::init()
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{
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// clear interrupts. to make sure the interrupt timer doesn't start until we've set it up.
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cli();
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// set up syntheziser
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// this is the timer 2 audio rate timer, fires an interrupt at 15625 Hz sampling rate
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TIMSK2 = 1<<OCIE2A; // interrupt enable audio timer
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OCR2A = 127;
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TCCR2A = 2; // CTC mode, counts up to 127 then resets
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TCCR2B = 0<<CS22 | 1<<CS21 | 0<<CS20;
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// OUTPUTS
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// sck + mosi + ss
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DDRB = (1 << DDB2) | (1 << DDB3) | (1 << DDB5);
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// dac_cs output
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DDRD = (1 << DDD6);
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// set up SPI port
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SPCR = 0x50;
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SPSR = 0x01;
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// DAC frame sync HIGH, so that the SPI port doesn't start wirting straight away
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PORTD |= (1<<6);
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// waveform setup
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//setSine();
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setWaveform(0);
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// frequency setup
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setFrequency(440);
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setSemitone1(0);
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setSemitone2(0);
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setSemitone3(0);
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setDetune(0);
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// gain setup
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setGain(1.0f);
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setGain1(1.0f);
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setGain2(1.0f);
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setGain3(1.0f);
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// envelope setup
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setEnvStage(0);
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disableEnvelope();
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env = 0;
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setAttack(4);
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setDecay(90);
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setSustain(32);
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setRelease(64);
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setVelSustain(0);
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sei(); // global interrupt enable
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Serial.println("MUSIC INITIALIZED!");
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}
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/////////////////////////////////////
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//
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// FREQUENCY AND DETUNE FUNCTIONS
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//
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/////////////////////////////////////
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void MMusic::setFrequency(float freq)
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{
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period1 = uint16_t(((freq * semi1 * (1 + detune1 + bend)) * 65536.0) / SAMPLE_RATE);
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period2 = uint16_t(((freq * semi2 * (1 + detune2 + bend)) * 65536.0) / SAMPLE_RATE);
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period3 = uint16_t(((freq * semi3 * (1 + detune3 + bend)) * 65536.0) / SAMPLE_RATE);
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frequency = freq;
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frequency1 = freq;
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frequency2 = freq;
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frequency3 = freq;
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}
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void MMusic::setFrequency1(float freq)
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{
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frequency1 = freq;
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period1 = uint16_t(((frequency1 * semi1 * (1 + detune1 + bend)) * 65536.0) / SAMPLE_RATE);
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}
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void MMusic::setFrequency2(float freq)
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{
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frequency2 = freq;
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period2 = uint16_t(((frequency2 * semi2 * (1 + detune2 + bend)) * 65536.0) / SAMPLE_RATE);
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}
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void MMusic::setFrequency3(float freq)
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{
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frequency3 = freq;
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period3 = uint16_t(((frequency3 * semi3 * (1 + detune3 + bend)) * 65536.0) / SAMPLE_RATE);
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}
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void MMusic::setSemitone1(int8_t semi)
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{
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if(-25 < semi && semi < 25){
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semi1 = semitoneTable[semi+24];
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} else if (semi < -24) {
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semi1 = semitoneTable[0];
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} else {
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semi1 = semitoneTable[48];
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}
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period1 = uint16_t(((frequency1 * semi1 * (1 + detune1 + bend)) * 65536.0) / SAMPLE_RATE);
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}
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void MMusic::setSemitone2(int8_t semi)
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{
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if(-25 < semi && semi < 25){
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semi2 = semitoneTable[semi+24];
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} else if (semi < -24) {
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semi2 = semitoneTable[0];
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} else {
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semi2 = semitoneTable[48];
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}
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period2 = uint16_t(((frequency2 * semi2 * (1 + detune2 + bend)) * 65536.0) / SAMPLE_RATE);
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}
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void MMusic::setSemitone3(int8_t semi)
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{
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if(-25 < semi && semi < 25){
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semi3 = semitoneTable[semi+24];
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} else if (semi < -24) {
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semi3 = semitoneTable[0];
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} else {
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semi3 = semitoneTable[48];
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}
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period3 = uint16_t(((frequency3 * semi3 * (1 + detune3 + bend)) * 65536.0) / SAMPLE_RATE);
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}
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void MMusic::setDetune(float detune)
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{
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detune1 = 0.0;
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detune2 = detune;
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detune3 = -detune;
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period2 = uint16_t(((frequency2 * semi2 * (1 + detune2 + bend)) * 65536.0) / SAMPLE_RATE);
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period3 = uint16_t(((frequency3 * semi3 * (1 + detune3 + bend)) * 65536.0) / SAMPLE_RATE);
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}
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void MMusic::setDetune1(float detune)
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{
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detune1 = detune;
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period1 = uint16_t(((frequency1 * semi1 * (1 + detune1 + bend)) * 65536.0) / SAMPLE_RATE);
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}
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void MMusic::setDetune2(float detune)
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{
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detune2 = detune;
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period2 = uint16_t(((frequency2 * semi2 * (1 + detune2 + bend)) * 65536.0) / SAMPLE_RATE);
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}
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void MMusic::setDetune3(float detune)
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{
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detune3 = detune;
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period3 = uint16_t(((frequency3 * semi3 * (1 + detune3 + bend)) * 65536.0) / SAMPLE_RATE);
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}
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void MMusic::pitchBend(float b)
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{
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bend = b;
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period1 = uint16_t(((frequency1 * semi1 * (1 + detune1 + bend)) * 65536.0) / SAMPLE_RATE);
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period2 = uint16_t(((frequency2 * semi2 * (1 + detune2 + bend)) * 65536.0) / SAMPLE_RATE);
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period3 = uint16_t(((frequency3 * semi3 * (1 + detune3 + bend)) * 65536.0) / SAMPLE_RATE);
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}
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/////////////////////////////////////
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//
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// WAVEFORM FUNCTIONS
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//
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/////////////////////////////////////
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void MMusic::setWaveform(uint16_t waveForm)
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{
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waveForm1 = waveForm * 256;
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waveForm2 = waveForm * 256;
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waveForm3 = waveForm * 256;
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}
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void MMusic::setWaveform1(uint16_t waveForm)
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{
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waveForm1 = waveForm * 256;
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}
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void MMusic::setWaveform2(uint16_t waveForm)
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{
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waveForm2 = waveForm * 256;
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}
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void MMusic::setWaveform3(uint16_t waveForm)
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{
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waveForm3 = waveForm * 256;
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}
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/////////////////////////////////////
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//
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// GAIN FUNCTIONS
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//
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/////////////////////////////////////
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void MMusic::setGainFloat(float value)
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{
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gain = uint16_t(value * 65535);
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gain1 = gain;
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gain2 = gain;
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gain3 = gain;
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}
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void MMusic::setGain16bit(uint16_t value)
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{
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gain = value;
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gain1 = value;
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gain2 = value;
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gain3 = value;
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}
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void MMusic::setGain(float value)
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{
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gain = uint16_t(value * 65535);
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gain1 = gain;
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gain2 = gain;
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gain3 = gain;
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}
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void MMusic::setGain(uint16_t value)
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{
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gain = value;
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gain1 = value;
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gain2 = value;
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gain3 = value;
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}
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void MMusic::setGain1(float value)
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{
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gain1 = uint16_t(value * 65535);
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}
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void MMusic::setGain2(float value)
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{
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gain2 = uint16_t(value * 65535);
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}
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void MMusic::setGain3(float value)
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{
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gain3 = uint16_t(value * 65535);
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}
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void MMusic::setGain1(uint16_t value)
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{
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gain1 = value;
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}
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void MMusic::setGain2(uint16_t value)
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{
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gain2 = value;
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}
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void MMusic::setGain3(uint16_t value)
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{
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gain3 = value;
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}
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float MMusic::getGainFloat()
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{
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return float(gain);
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}
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uint16_t MMusic::getGain()
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{
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return gain;
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}
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/////////////////////////////////////
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//
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// NOTE_ON/OFF FUNCTIONS
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//
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/////////////////////////////////////
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void MMusic::noteOn(uint8_t note, uint8_t vel)
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{
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envStage = 1;
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setVelSustain(vel);
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setVelPeak(vel);
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notePlayed = note;
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memcpy_P(&frequency16bit, &hertsTable[notePlayed],2);
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setFrequency1(frequency16bit);
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setFrequency2(frequency16bit);
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setFrequency3(frequency16bit);
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}
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void MMusic::noteOn(uint8_t note)
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{
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envStage = 1;
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setVelSustain(127);
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setVelPeak(127);
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notePlayed = note;
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memcpy_P(&frequency16bit, &hertsTable[notePlayed],2);
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setFrequency1(frequency16bit);
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setFrequency2(frequency16bit);
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setFrequency3(frequency16bit);
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}
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void MMusic::noteOff(uint8_t note)
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{
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if(notePlayed == note) {
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envStage = 4;
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}
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}
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void MMusic::noteOff()
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{
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envStage = 4;
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}
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/////////////////////////////////////
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//
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// ENVELOPE FUNCTIONS
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//
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/////////////////////////////////////
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void MMusic::enableEnvelope()
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{
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envelopeOn = true;
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}
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void MMusic::disableEnvelope()
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{
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envelopeOn = false;
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}
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void MMusic::setEnvStage(uint8_t stage)
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{
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envStage = stage;
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}
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void MMusic::setAttack16bit(uint16_t att)
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{
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attack = att;
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}
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void MMusic::setDecay16bit(uint16_t dec)
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{
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decay = dec;
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}
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void MMusic::setSustain16bit(uint16_t sus)
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{
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sustain = sus;
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}
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void MMusic::setRelease16bit(uint16_t rel)
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{
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release = rel;
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}
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void MMusic::setAttack(uint8_t att)
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{
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if(att>127) att = 127;
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memcpy_P(&attack, &envTimeTable[127 - att],2);
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//attack = envTimeTable[127 - att];
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}
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void MMusic::setDecay(uint8_t dec)
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{
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if(dec>127) dec = 127;
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memcpy_P(&decay, &envTimeTable[127 - dec],2);
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//decay = envTimeTable[127 - dec];
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}
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void MMusic::setSustain(uint8_t sus)
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{
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sustain = ((sus * MAX_ENV_GAIN)/128);
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}
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void MMusic::setRelease(uint8_t rel)
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{
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if(rel>127) rel = 127;
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memcpy_P(&release, &envTimeTable[127 - rel],2);
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//release = envTimeTable[127 - rel];
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}
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void MMusic::setVelSustain(uint8_t vel)
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{
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velSustain = vel * (sustain / 128);
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}
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void MMusic::setVelPeak(uint8_t vel)
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{
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velPeak = vel * (MAX_ENV_GAIN / 128);
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}
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/////////////////////////////////////////////////////////
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//
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// 8 BIT WAVETABLE - AUDIO INTERRUPT SERVICE ROUTINE
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//
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/////////////////////////////////////////////////////////
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void inline MMusic::synthInterrupt8bit()
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{
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// Frame sync low for SPI (making it low here so that we can measure lenght of interrupt with scope)
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PORTD &= ~(1<<6);
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accumulator1 = accumulator1 + period1;
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index1 = accumulator1 >> 8;
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//oscil1 = 0;
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memcpy_P(&oscil1, &waveTable[index1 + waveForm1],1);
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sample = (oscil1 * gain1);
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#if(NUM_OSCILLATORS==2 || NUM_OSCILLATORS==3)
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accumulator2 = accumulator2 + period2;
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index2 = accumulator2 >> 8;
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//oscil2 = 0;
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memcpy_P(&oscil2, &waveTable[index2 + waveForm2],1);
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sample += (oscil2 * gain2);
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#endif
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#if NUM_OSCILLATORS==3
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accumulator3 = accumulator3 + period3;
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index3 = accumulator3 >> 8;
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//oscil3 = 0;
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memcpy_P(&oscil3, &waveTable[index3 + waveForm3],1);
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sample += (oscil3 * gain3);
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#endif
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sample >>= 10;
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// AMPLIFICATION ENVELOPE
|
|
// Amplification envelope is calculated here
|
|
if(envelopeOn) {
|
|
|
|
// Attack
|
|
if(envStage == 1) {
|
|
env += attack;
|
|
if(velPeak < env) {
|
|
env = velPeak;
|
|
envStage = 2;
|
|
}
|
|
}
|
|
// Decay
|
|
else if(envStage == 2) {
|
|
env -= decay;
|
|
if(env < velSustain || MAX_ENV_GAIN < env) {
|
|
env = velSustain;
|
|
envStage = 3;
|
|
}
|
|
}
|
|
// Sustain
|
|
else if (envStage == 3) {
|
|
env = velSustain;
|
|
}
|
|
|
|
// Release
|
|
else if (envStage == 4) {
|
|
env -= release;
|
|
if(MAX_ENV_GAIN < env) {
|
|
env = 0;
|
|
envStage = 0;
|
|
}
|
|
}
|
|
|
|
// No gain
|
|
else if (envStage == 0) {
|
|
env = 0;
|
|
accumulator1 = 0;
|
|
accumulator2 = 0;
|
|
accumulator3 = 0;
|
|
}
|
|
|
|
} else {
|
|
env = 65535;
|
|
}
|
|
|
|
// Adding the amplification envelope (16bit) we bring it back to the 16bit frame again afterwards.
|
|
sample = (env * sample) >> 16;
|
|
|
|
|
|
// Formatting the samples to be transfered to the MCP4921 DAC
|
|
dacSPI0 = sample >> 8;
|
|
dacSPI0 >>= 4;
|
|
dacSPI0 |= 0x30;
|
|
dacSPI1 = sample >> 4;
|
|
|
|
SPCR |= (1 << MSTR);
|
|
|
|
// transmit value out the SPI port
|
|
SPDR = dacSPI0;
|
|
while (!(SPSR & (1<<SPIF))); // Maybe this can be optimised
|
|
SPDR = dacSPI1;
|
|
while (!(SPSR & (1<<SPIF))); // Maybe this can be optimised
|
|
|
|
// Frame sync high
|
|
PORTD |= (1<<6);
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/////////////////////////////////////////////////////////
|
|
//
|
|
// 12 BIT SINEWAVE - AUDIO INTERRUPT SERVICE ROUTINE
|
|
//
|
|
/////////////////////////////////////////////////////////
|
|
|
|
|
|
void MMusic::synthInterrupt12bitSine()
|
|
{
|
|
// Frame sync low for SPI (making it low here so that we can measure lenght of interrupt with scope)
|
|
PORTD &= ~(1<<6);
|
|
|
|
accumulator1 = accumulator1 + period1;
|
|
index1 = accumulator1 >> 4;
|
|
memcpy_P(&oscil1, &sineTable[index1],2);
|
|
sample = (oscil1 * gain1) << 2;
|
|
|
|
#if(NUM_OSCILLATORS==2 || NUM_OSCILLATORS==3)
|
|
|
|
accumulator2 = accumulator2 + period2;
|
|
index2 = accumulator2 >> 4;
|
|
memcpy_P(&oscil2, &sineTable[index2],2);
|
|
sample += (oscil2 * gain2) << 2;
|
|
|
|
#endif
|
|
#if NUM_OSCILLATORS==3
|
|
|
|
accumulator3 = accumulator3 + period3;
|
|
index3 = accumulator3 >> 4;
|
|
memcpy_P(&oscil3, &sineTable[index3],2);
|
|
sample += (oscil3 * gain3) << 2;
|
|
|
|
#endif
|
|
|
|
sample >>= 16;
|
|
|
|
|
|
// AMPLIFICATION ENVELOPE
|
|
// Amplification envelope is calculated here
|
|
if(envelopeOn) {
|
|
|
|
// Attack
|
|
if(envStage == 1) {
|
|
env += attack;
|
|
if(velPeak < env) {
|
|
env = velPeak;
|
|
envStage = 2;
|
|
}
|
|
}
|
|
// Decay
|
|
else if(envStage == 2) {
|
|
env -= decay;
|
|
if(env < velSustain || MAX_ENV_GAIN < env) {
|
|
env = velSustain;
|
|
envStage = 3;
|
|
}
|
|
}
|
|
// Sustain
|
|
else if (envStage == 3) {
|
|
env = velSustain;
|
|
}
|
|
|
|
// Release
|
|
else if (envStage == 4) {
|
|
env -= release;
|
|
if(MAX_ENV_GAIN < env) {
|
|
env = 0;
|
|
envStage = 0;
|
|
}
|
|
}
|
|
/*
|
|
// No gain
|
|
else if (envStage == 0) {
|
|
env = 0;
|
|
//accumulator1 = 0;
|
|
//accumulator2 = 0;
|
|
//accumulator3 = 0;
|
|
}
|
|
*/
|
|
} else {
|
|
env = 65535;
|
|
}
|
|
|
|
// Adding the amplification envelope (16bit) we bring it back to the 16bit frame again afterwards.
|
|
sample = (env * sample) >> 16;
|
|
|
|
// Formatting the samples to be transfered to the MCP4921 DAC
|
|
dacSPI0 = sample >> 8;
|
|
dacSPI0 >>= 4;
|
|
dacSPI0 |= 0x30;
|
|
dacSPI1 = sample >> 4;
|
|
|
|
SPCR |= (1 << MSTR);
|
|
|
|
// transmit value out the SPI port
|
|
SPDR = dacSPI0;
|
|
while (!(SPSR & (1<<SPIF))); // Maybe this can be optimised
|
|
SPDR = dacSPI1;
|
|
while (!(SPSR & (1<<SPIF))); // Maybe this can be optimised
|
|
|
|
// Frame sync high
|
|
PORTD |= (1<<6);
|
|
|
|
}
|
|
|
|
|
|
|