diff --git a/097TET/097TET.ino b/097TET/097TET.ino new file mode 100644 index 0000000..8dce476 --- /dev/null +++ b/097TET/097TET.ino @@ -0,0 +1,104 @@ +// Basic demo for configuring the MCP4728 4-Channel 12-bit I2C DAC +#include +#include + +Adafruit_MCP4728 mcp; + + +// 1 3 5 7 hexany log2 +float tuning[22]; +// bassline +//int pitch[] = { 1, 2, -1, 0, -1, 1, -1, 0, -1, 1, -1 }; +//float dur[] = { 0.25, 0.25, 0.5, 0.25, 0.5, 0.25, 0.5, 0.25, 0.5, 0.25, 0.5 }; +// kick +//int pitch[] = { 1, -1, 1, -1, 1, -1, 1, -1, 1 }; +//float dur[] = { 0.25, 0.75, 0.25, 0.75, 0.25, 0.75, 0.25, 0.75}; +int pitch[] = { 9, 7, 5, 3, 8, 6, 5, 3 }; +float dur[] = { 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5 }; + + +float gate = 0.25; +int bpm = 140; +int phrase = 8; +float beat_s = 60.0 / (float)bpm; +int beat_m = round(1000.0 * beat_s); +float voltrange = 4.85; // measured this, probably not accurate +float octave = 4096.0 / voltrange; // number of DAC steps in an octave +float mod_b = 3.141592653589793 / 4.0; + + +int s; +bool noteon = false; +long play_t; +long release_t; +long last_t; +long init_t; + + +void setup(void) { + Serial.begin(115200); + while (!Serial) + delay(10); // will pause Zero, Leonardo, etc until serial console opens + + if (!mcp.begin(0x64)) { + Serial.println("Failed to find MCP4728 chip"); + while (1) { + delay(10); + } + Serial.println("MCP4728 initialised"); + } + + mcp.setChannelValue(MCP4728_CHANNEL_B, 0); + + float n0 = 0; + for( int i = 0; i < 22; i++ ) { + tuning[i] = round(n0 + octave * (float)i / 7.0); + } + + s = 0; + release_t = 0; + play_t = 0; + last_t = millis(); + init_t = last_t; +} + + + +void loop() { + long now = millis(); + if( noteon ) { + if( now - last_t > release_t ) { + noteOff(); + last_t = now; + play_t = round(beat_m * dur[s] * (1.0 - gate)); + noteon = false; + s += 1; + if( s == phrase ) { + s = 0; + } + } + } else { + if( now - last_t > play_t ) { + noteOn(pitch[s]); + last_t = now; + release_t = round(beat_m * dur[s] * gate); + noteon = true; + } + } + // sychronise this better + long mod_t = (now - init_t); + float mod = 0.5 + 0.5 * sin(mod_b * (float)mod_t / (float)beat_m); + mcp.setChannelValue(MCP4728_CHANNEL_C, round(4095.0 * mod)); +} + + +void noteOn(int note) { + if( note > -1 ) { + mcp.setChannelValue(MCP4728_CHANNEL_A, tuning[note]); + mcp.setChannelValue(MCP4728_CHANNEL_B, 4095); + } +} + +void noteOff() { + mcp.setChannelValue(MCP4728_CHANNEL_B, 0); +} diff --git a/10MultiMod/10MultiMod.ino b/10MultiMod/10MultiMod.ino new file mode 100644 index 0000000..927d797 --- /dev/null +++ b/10MultiMod/10MultiMod.ino @@ -0,0 +1,49 @@ +// Basic demo for configuring the MCP4728 4-Channel 12-bit I2C DAC +#include +#include + +Adafruit_MCP4728 mcp; + + +int bpm = 98; +float beat_s = 60.0 / (float)bpm; +int beat_m = round(1000.0 * beat_s); +long init_t; + +float pi = 3.141592653589793; +float mod_a = pi; +float mod_b = pi / 4.0; +float mod_c = pi / 3.0; +float mod_d = pi / 5.0; + + + +void setup(void) { + Serial.begin(115200); + while (!Serial) + delay(10); // will pause Zero, Leonardo, etc until serial console opens + + if (!mcp.begin(0x64)) { + Serial.println("Failed to find MCP4728 chip"); + while (1) { + delay(10); + } + Serial.println("MCP4728 initialised"); + } + + init_t = millis(); + mcp.setChannelValue(MCP4728_CHANNEL_B, 0); + +} + + +void loop() { + long now = millis(); + long mod_t = (now - init_t); + float tf = (float)mod_t / (float)beat_m; + uint16_t a = round(4095.0 * (0.5 + 0.5 * sin(mod_a * tf))); + uint16_t b = round(4095.0 * (0.5 + 0.5 * sin(mod_b * tf))); + uint16_t c = round(4095.0 * (0.5 + 0.5 * sin(mod_c * tf))); + uint16_t d = round(4095.0 * (0.5 + 0.5 * sin(mod_d * tf))); + mcp.fastWrite(a, b, c, d); +} diff --git a/11KarplusStrongAgain/11KarplusStrongAgain.ino b/11KarplusStrongAgain/11KarplusStrongAgain.ino new file mode 100644 index 0000000..5f3a51d --- /dev/null +++ b/11KarplusStrongAgain/11KarplusStrongAgain.ino @@ -0,0 +1,93 @@ +// Very basic Karplus-Strong + +// based on this explanation http://sites.music.columbia.edu/cmc/MusicAndComputers/chapter4/04_09.php + + +#include +#include + +Adafruit_MCP4728 mcp; + +#define nsamp 256 +#define dacmax 256 + +unsigned int phase; +unsigned int length; +unsigned int repeats; +int note = 0; +int freqs[] = { 256, 112, 102, 96, 84, 76, 64, 56, 50, 48, 42, 38, 34, 32 }; +int tune2[] = { 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 1, -1, -1, -1 }; + +byte waveform[nsamp]; + +int pd = 30; + +void setup() { + + cli(); + +//set timer1 interrupt at 1Hz + TCCR1A = 0;// set entire TCCR1A register to 0 + TCCR1B = 0;// same for TCCR1B + TCNT1 = 0;//initialize counter value to 0 + // set compare match register for 1hz increments + //OCR1A = 15624;// = (16*10^6) / (1*1024) - 1 (must be <65536) + //OCR1A = 7812;// = (16*10^6) / (1*1024) - 1 (must be <65536) + OCR1A = 800; + // turn on CTC mode + TCCR1B |= (1 << WGM12); + // Set CS10 and CS12 bits for 1024 escaler + TCCR1B |= (1 << CS12) | (1 << CS10); + // enable timer compare interrupt + TIMSK1 |= (1 << OCIE1A); + + sei(); + + + + if (!mcp.begin(0x64)) { + while (1) { + delay(100); + } + } + + randomSeed(analogRead(A0)); + mcp.setSpeed(800000L); + + phase=0; + note=0; +} + +ISR(TIMER1_COMPA_vect){//timer1 + if( tune2[note] > -1 ) { + length=freqs[tune2[note]]; + for (int i=0; i 15 ) { + note = 0; + } + pd = analogRead(A0) >> 4; +} + + + +void loop() { + byte s1, s2; + int p0 = phase; + int p1 = phase - pd; + if( p1 < 0 ) { + p1 += length; + } + phase += 1; + if( phase >= length ) { + phase = 0; + } + s1 = waveform[p1]; + s2 = waveform[p0]; + waveform[p0] = ( s1 & s2 ) + ((s1 ^ s2) >> 1); + mcp.fastWrite(s1 << 4, 0, 0, 0); +} + diff --git a/TODO.md b/TODO.md index 7a65022..c1408c7 100644 --- a/TODO.md +++ b/TODO.md @@ -2,10 +2,10 @@ Sunday 6 October -6 - Wavetable updates -7 - Change a sequence while it's playing -8 - Sound clouds -9 - 7TET groove -10 - Drum pattern -11 - FM -12 - Karplus-Strong +s 6 - Wavetable updates +m 7 - Change a sequence while it's playing +t 8 - Sound clouds +w 9 - 7TET groove +t 10 - Drum pattern +f 11 - FM +s 12 - Karplus-Strong