Sequencer in sync is starting to come together

Xmas/Xmas.ino

@@ -8,12 +8,42 @@ Adafruit_MCP4728 mcp;
 float tuning[16];
 // 0 = A, 8 = F (tonic)
 
-int m1[] =   { 3, 8, 8, 10, 8, 7, 5, 5, 5, 10, 10, 12, 10, 8, 7, 3, 7, 12, 12, 13, 12, 10, 8, 5, 3, 3, 5, 10, 7, 8, 3, 8, 8, 8, 7, 7, 8, 7, 5, 3, 10, 12, 10, 10, 8, 8, 15, 3, 3, 3, 5, 10, 7, 8  };
+/*
-int d1[] = { 2, 2, 1, 1, 1, 1, 2, 2, 2, 2, 1, 1, 1, 1, 2, 2, 2, 2, 1,  1, 1, 1, 2, 2, 1, 1, 2, 2, 2, 4, 2, 2, 2, 2, 4, 2, 2, 2, 2, 4, 2, 2, 1, 1, 1, 1,  2, 2, 1, 1, 2, 2, 2, 4 };
+
-int m2[] =   { -1, 8, 1, 2, 3, 4, 5, 0, 1, 3, 8, 8, 3, 5, 7, 8, 7, 0, 1, 3, 8  };
+For each note: pitch, absolute start time (in beats) and duration - either preset these or compute it
-int d2[] = { 2,  6, 6, 6, 6, 6, 4, 2, 4, 2, 6, 6, 6, 6, 6, 6, 4, 2, 4, 2, 4  };
+
+For a sequencer: is time-elapsed > start time of next note?
+
+if yes - set the play time to now, increment the note
+  - if a note happens to be playing now, doesn't matter, just change the pitch and reset the timer
+
+if no - is there still a note playing?
+
+if still playing, is now - play start > the note's duration? if so, stop playing
+
+the absolute start time should include a count-in
+
+*/
+
+// int m1[] =   { 3, 8, 8, 10,  8,  7,  5,  5,  5, 10, 10, 12, 10,  8,  7,  3,  7, 12, 12, 13, 12, 10,  8,  5, 3,  3,  5,  10,  7,  8,  3, 8,   8,  8,  7,  7,  8,  7,  5,  3, 10, 12, 10, 10, 8, 8,   15, 3,   3,  3, 5, 10, 7, 8  };
+// int s1[] =   { 2, 4, 5, 6, 7, 8, 10, 12, 14, 16, 17, 18, 19, 20, 22, 24, 26, 28, 29, 30, 31, 32, 34, 36, 37, 38, 40, 42, 44, 48, 50, 52, 54, 56, 60, 62, 64, 66, 68, 72, 74, 76, 77, 78, 79, 80, 82, 84, 85, 86, 88, 90, 92, 96 };
+// int d1[] =   { 2, 2, 1, 1, 1, 1, 2, 2, 2, 2, 1, 1, 1, 1, 2, 2, 2, 2, 1,  1, 1, 1, 2, 2, 1, 1, 2, 2, 2, 4, 2, 2, 2, 2, 4, 2, 2, 2, 2, 4, 2, 2, 1, 1, 1, 1,  2, 2, 1, 1, 2, 2, 2, 4 };
+
+//int m2[] =   { -1, 8, 1, 2, 3, 4, 5, 0, 1, 3, 8, 8, 3, 5, 7, 8, 7, 0, 1, 3, 8  };
+//int d2[] =   { 2,  6, 6, 6, 6, 6, 4, 2, 4, 2, 6, 6, 6, 6, 6, 6, 4, 2, 4, 2, 4  };
+
+
+
+int m1[] =     { 0,    2,    4,   5,     7,   9,  11, 12 };
+int s1[] =     { 3,    5,    7,   9,    11,  13,  15, 17 };
+float d1[] =   { 1.0, 0.5, 1.0, 0.5,  1.0, 0.5, 1.0, 0.5  };
+int m2[] =     { 0,    3,    6,   9,     1,   4,  7, 11, 2, 5, 8, 13, 1, 4, 7, 11  };
+int s2[] =     { 1,    2,    3,   4,    5,  6,  7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
+float d2[] =   { 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5 };
+
+
 float gate = 0.5;
-int bpm = 240;
+int bpm = 180;
 float beat_s = 60.0 / (float)bpm;
 int beat_m = round(1000.0 * beat_s); 
 float voltrange = 5.0; 
@@ -21,21 +51,23 @@ float octave = 4096.0 / voltrange; // number of DAC steps in an octave
 float mod_b = 3.141592653589793 / 4.0;
 
 typedef struct {
-  int s = 0;
+  int s = -1;
-  bool noteOn = false;
+  int playing = 0;
   long play = 0;
   long rel = 0;
   long last = 0;
   long init = 0;
   int *melody;
-  int *duration;
+  int *start;
+  float *duration;
   int len = 0;
   MCP4728_channel_t pitch;
   MCP4728_channel_t gate;
 } sequencer;
 
 sequencer seq1, seq2;
-
+long start_time;
+int repeat = 8;
 
 void setup(void) {
   Serial.begin(115200);
@@ -50,17 +82,18 @@ void setup(void) {
     Serial.println("MCP4728 initialised");
   }
 
-  mcp.setChannelValue(MCP4728_CHANNEL_B, 0);
 
   float n0 = 0;
   for( int i = 0; i < 16; i++ ) {
       tuning[i] = round(n0 + octave * (float)i / 12.0);
   }
   long now = millis();
+  start_time = now;
   seq1.last = now;
   seq1.pitch = MCP4728_CHANNEL_A;
   seq1.gate = MCP4728_CHANNEL_B;
   seq1.melody = m1;
+  seq1.start = s1;
   seq1.duration = d1;
   seq1.len = sizeof(m1) / sizeof(m1[0]);
 
@@ -69,6 +102,7 @@ void setup(void) {
   seq2.gate = MCP4728_CHANNEL_D;
   seq2.melody = m2;
   seq2.duration = d2;
+  seq2.start = s2;
   seq2.len = sizeof(m2) / sizeof(m2[0]);
 
 }
@@ -76,41 +110,44 @@ void setup(void) {
 
 void loop() {
   long now = millis();
-  runSequencer(seq1, now);
+  float beat = (float)(now - start_time) / (float)beat_m;
-  runSequencer(seq2, now);
+  runSequencer(seq1, now, beat);
+  runSequencer(seq2, now, beat);
 }
 
-void runSequencer(sequencer& seq, long now) {
+void runSequencer(sequencer& seq, long now, float beat) {
-  if( seq.noteOn ) {
+  if( seq.s < seq.len - 1 ) {
-    if( now - seq.last > seq.rel ) {
+    if( beat > (float)seq.start[seq.s + 1] ) {
-      noteOff(seq);
-      seq.last = now;
-      seq.play = 0; // no gate for now
-      seq.noteOn = false;
       seq.s += 1;
-      if( seq.s > seq.len ) {
+      Serial.print("seq / note ");
-        seq.s = 0;
+      Serial.print(seq.s);
+      Serial.print(" / ");
+      Serial.println(seq.melody[seq.s]);
+      seq.rel = now + round((float)beat_m * seq.duration[seq.s]);
+      if( seq.melody[seq.s] > -1 ) {
+        mcp.setChannelValue(seq.pitch, tuning[seq.melody[seq.s]]);
+        mcp.setChannelValue(seq.gate, 4095);
       }
-    }
+      seq.playing = 1;
-  } else {
-    if( now - seq.last > seq.play ) {
-      noteOn(seq, seq.melody[seq.s]);
-      seq.last = now;
-      seq.rel = beat_m * seq.duration[seq.s];
-      seq.noteOn = true;
     }
   }
-  
+  if( seq.playing ) {
-}
+    if( now > seq.rel ) {
-
+      Serial.println("release");
-
+      mcp.setChannelValue(seq.gate, 0);
-void noteOn(sequencer seq, int note) {
+      seq.playing = 0;
-  if( note > -1 ) {
+    }
-    mcp.setChannelValue(seq.pitch, tuning[note]);
-    mcp.setChannelValue(seq.gate, 4095);
   }
 }
 
-void noteOff(sequencer seq) {
+
-    mcp.setChannelValue(seq.gate, 0);
+// void noteOn(sequencer& seq, int note) {
-}
+//   if( note > -1 ) {
+//     mcp.setChannelValue(seq.pitch, tuning[note]);
+//     mcp.setChannelValue(seq.gate, 4095);
+//   }
+// }
+
+// void noteOff(sequencer& seq) {
+//     mcp.setChannelValue(seq.gate, 0);
+// }