Changes to README and TODO

14Slower/14Slower.ino

@@ -16,8 +16,8 @@ int note = 0;
 // int pitch[] = { 8, 4, 5, -1, 4, 3, -1, 2, 3, 4, -1, 6, 3, 4, 5, -1 };
 // float dur[] = { 0.5,0.5,0.5,0.5,0.25,0.25,0.25,0.25,0.5,0.5,0.5,0.5,0.25,0.25,0.25,0.25,0.25, };
 
-int pitch[] = { 1, -1, -1, -1, 1, -1, -1, -1, 1, -1, -1, -1, 0, -1, -1, -1  };
-float dur[] = { 3, 0, 0, 0, 3, 0, 0, 0, 3, 0, 0, 0, 3, 0, 0, 0 };
+int pitch[] = { 12, -1, 11, -1, 12, -1, 15, -1, 12, -1, 11, -1, -1, -1, -1, -1  };
+float dur[] = { 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0 };
 
 
 int phrase = 16;
@@ -43,7 +43,7 @@ void setup() {
   //OCR1A = 15624;// = (16*10^6) / (1*1024) - 1 (must be <65536)
   //OCR1A = 7812;// = (16*10^6) / (1*1024) - 1 (must be <65536)
   //OCR1A = 15624;
-  OCR1A = 31248;
+  OCR1A = 48000;
   // turn on CTC mode
   TCCR1B |= (1 << WGM12);
   // Set CS10 and CS12 bits for 1024 escaler

19CloudPitch/19CloudPitch.ino

@@ -0,0 +1,88 @@
+// Basic demo for configuring the MCP4728 4-Channel 12-bit I2C DAC
+#include <Adafruit_MCP4728.h>
+#include <Wire.h>
+
+Adafruit_MCP4728 mcp;
+
+
+// idea behind this - sequence a cloud of gate events
+
+
+float hexany[] = { 0.12928301694496647, 0.32192809488736235, 0.3923174227787603, 0.5849625007211562, 0.8073549220576041, 0.9068905956085185 };
+float tuning[18];
+
+int chord[10] = { 0, 2, 4, 6, 8, 7, 11, 15, 14, 10 };
+
+int bpm = 60;
+float beat_s = 60.0 / (float)bpm;
+int beat_m = round(1000.0 * beat_s); 
+float mod_b = 3.141592653589793 / 4.0;
+float voltrange = 4.85;  // measured this, probably not accurate
+float octave = 4096.0 / voltrange; // number of DAC steps in an octave
+
+
+int gate = 0;
+int gatel = 1000;
+int tick = 16;
+long init_t;
+float p_gate = 0.0;
+
+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");
+  }
+
+  float n0 = 0;
+  for( int o = 0; o < 3; o++ ) {
+    for( int i = 0; i < 18; i++ ) {
+      tuning[o * 6 + i] = round(n0 + octave * (o + hexany[i]));
+    }
+  }
+
+
+  init_t = millis();
+
+  mcp.setChannelValue(MCP4728_CHANNEL_B, 0);
+}
+
+
+
+void loop() {
+  int note;
+  int k = 0;
+  if( gate > 0 ) {
+    gate--;
+    if( gate == 0 ) {
+      mcp.setChannelValue(MCP4728_CHANNEL_B, 0);
+    } 
+  } else {
+    long now = millis();
+    long mod_t = now - init_t;
+    tick--;
+    if( tick == 0 ) {
+      tick = 32;
+      p_gate = sin(mod_b * (float)mod_t / (float)beat_m);
+    }
+    if( (float)random(10000) / 20.0 < abs(p_gate)) {
+      if( p_gate > 0 ) {
+        note = random(5);
+      } else { 
+        note = 5 + random(5);
+      }
+      mcp.setChannelValue(MCP4728_CHANNEL_B, 4095);
+      mcp.setChannelValue(MCP4728_CHANNEL_A, tuning[note]);
+      gate = gatel;
+    }
+  }
+
+}
+
+

20Fibonacci/20Fibonacci.ino

@@ -0,0 +1,109 @@
+// can fibomod make an interesting noise?
+
+
+#include <Adafruit_MCP4728.h>
+#include <Wire.h>
+
+Adafruit_MCP4728 mcp;
+
+#define nsamp 1500
+#define dacmax 256
+
+unsigned int phase = 0;
+unsigned int fibo = 3;
+unsigned int scale = 0;
+unsigned int fibi = 0;
+unsigned int gate = 4095;
+unsigned int pmax = nsamp;
+unsigned int beat = 0;
+
+unsigned int fibosort[] = { 4,3,11,8,29,7,21,19,38,76,5,55,199,6,9,12,16,18,24,36,48,72,144,13,22,31,44,62,124,47,141,17,34,68,136,152,15,33,41,123,165,205,58,116,211,89,139,14,23,28,32,42,46,56,63,69,84,92,96,112,126,138,161,168,184,207,224,252,101,151,233,39,87,59,10,20,40,61,88,110,122,155,220,244,248,71,27,51,54,57,102,107,108,114,153,171,204,214,216,228,37,113,79,158,35,77,105,231,26,52,104,232,43,129,181,209,64,94,188,192,25,53,106,109,212,218,121,49,91,147,203,229,30,45,60,66,80,82,90,93,99,120,132,164,176,180,183,186,198,240,246,131,178,67,201,65,143,145,119,133,189,238,73,149,202,111,235,78,83,117,156,166,174,208,234,249,118,236,179,85,95,170,187,190,191,128,97,75,103,142,81,159,162,74,148,226,177,239,70,115,140,154,160,210,217,230,241,253,251,221,247,127,86,172,137,195,213,219,50,100,200,237,157,163,242,98,167,182,196,173,135,255,169,185,193,197,175,134,130,215,146,223,222,227,125,245,194,150,225,206,243,254,250 };
+
+
+byte waveform[nsamp];
+
+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 = 3200;
+  // turn on CTC mode
+  TCCR1B |= (1 << WGM12);
+  // Set CS10 and CS12 bits for 1024 prescaler
+  TCCR1B |= (1 << CS12) | (1 << CS10);  
+  // enable timer compare interrupt
+  TIMSK1 |= (1 << OCIE1A);
+
+  sei();
+
+
+
+  Serial.begin(115200);
+
+  if (!mcp.begin(0x64)) {
+    while (1) {
+      delay(100);
+    }
+  }
+
+  mcp.setSpeed(800000L);
+
+  for( int i = 0; i < nsamp; i++ ) {
+    waveform[i] = 1;
+  }
+  fibi = 3;
+  fibo =  3; //fibosort[fibi];
+  setwave();
+}
+
+void setwave(){
+  waveform[0] = 0;
+  waveform[1] = 1;
+  fibo = fibi; // fibosort[fibi];// + 3;
+  pmax = nsamp;
+  for (int i=2; i<nsamp; ++i){
+    waveform[i] = (waveform[i - 1] + waveform[i - 2]) % fibo;
+    if( waveform[i - 1] == 0 && waveform[i] == 1 ) {
+      pmax = i - 1;
+      break;
+    }
+  }
+  float scale = 256 / fibo;
+  for( int i = 0; i < nsamp; ++i ) {
+    waveform[i] *= scale;
+  }
+}
+
+ISR(TIMER1_COMPA_vect){//timer1
+  fibi++;
+  if( fibi == 67 ) {
+    fibi = 3;
+  }
+  
+  setwave();
+  phase = 0;
+  beat++;
+  if ( beat == 4 ) {
+    gate = 4095;
+    beat = 0;
+  }
+  
+}
+
+
+void loop() {
+  mcp.fastWrite(waveform[phase] << 4, gate, 0, 0);
+  phase += 1;
+  if( phase == pmax ) {
+    phase = 0;
+    gate = 0;
+  }
+}
+

README.md

@@ -3,4 +3,6 @@ Looptober 2024
 
 This year for Looptober I decided to use my Arduino (in combination with my
 modular synth rack) for every track. The source code for each day's track
-is here and the tracks are on [my Funkwhale server](https://music.mikelynch.org/library/albums/31/)
+is here and the tracks are on [my Funkwhale server](https://music.mikelynch.org/library/albums/31/)
+
+

TODO.md

@@ -1,11 +1,35 @@
 ## TODO 
-
-Sunday 6 October
+ 6 October
 
 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
+f 11 - Scratchy karplus-strong beats
+s 12 - sequencer 2
+s 13 - accidental FM synth
+m 14 - slow dank
+t 15 - rattatat
+w 16 - 
+t 17
+f 18
+s 19
+s 20
+m 21 
+t 22
+w 23
+t 24
+f 25
+s 26
+s 27
+m 28
+t 29
+w 30
+t 31
+
+More ideas
+
+deliberate FM synthesis
+KR to AR modulation and back
+Envelopes