add code to make an AVR chip play some improvised music

AVR_code/harmonisk_improvisasjon_v001.c.ino

@@ -0,0 +1,62 @@
+
+const int Output = 1;                                   // Can be 1 or 4
+// Cater for 16MHz, 8MHz, or 1MHz clock:
+const int Clock = ((F_CPU/1000000UL) == 16) ? 4 : ((F_CPU/1000000UL) == 8) ? 3 : 0;
+const uint8_t scale[] PROGMEM = {239,226,213,201,190,179,169,160,151,142,134,127};
+void note (int n, int octave) {
+  int prescaler = 8 + Clock - (octave + n/12);
+  if (prescaler<1 || prescaler>15 || octave==0) prescaler = 0;
+  DDRB = (DDRB & ~(1<<Output)) | (prescaler != 0)<<Output;
+  OCR1C = pgm_read_byte(&scale[n % 12]) - 1;
+  GTCCR = (Output == 4)<<COM1B0;
+  TCCR1 = 1<<CTC1 | (Output == 1)<<COM1A0 | prescaler<<CS10;
+}
+
+
+int cm[] = {0,3,7};
+int fm[] = {0,5,8};
+int g[] = {11,7,2,5,8};
+int member = 3;
+int note_length = 50;
+int n = 0;
+int octave = 1;
+int akkord = 0;
+unsigned long seconds = 0;
+unsigned long prev = 0;
+
+void setup() {
+  // put your setup code here, to run once:
+  //pinMode(1, OUTPUT);
+}
+
+void loop() {
+  // put your main code here, to run repeatedly:
+
+  note_length = random(30,70);
+  octave = random(3,7);
+  
+  seconds = millis();
+  seconds = seconds/1000;
+  if (prev != seconds) 
+    akkord = random(0,3);
+  prev = seconds;
+
+  switch (akkord) {
+    case 0: // cm
+      member = random(3);
+      n = cm[member];
+      break;
+    case 1: // fm
+      member = random(3);
+      n = fm[member];
+      break;
+    case 2: // g
+      member = random(5);
+      n = g[member];
+      break;
+  }
+
+  note(n,octave);
+
+  delay(note_length);
+}