/* LucidTronix Heart Matrix LEO LED Display. * Demoing the heart matrix clock and sound sensor * For instructions details and schematic, See: * http://www.lucidtronix.com/tutorials/57 */#include #include #include #include // dataPin is on 5, Latch is on 6, and clock is on 7HeartMatrix hm = HeartMatrix(5,6,7);MCP79410 clock = MCP79410();int mode = 0;int num_modes = 3;unsigned long last_press = 0;// clock global variablesString stime = "";unsigned int last_update = 0;// sound global variablesconst int buffer_size = 15;int noises[buffer_size];const int num_cols = 10;int volumes[num_cols];int cur_index = 0;unsigned long last_shift = 0;int mic_pin = 1;int delay_speed = 40;unsigned long max_var = 0;unsigned long min_var = 99999999;void setup() {   Serial.begin(9600);   MsTimer2::set(1,displayer2);   MsTimer2::start();   for (int i = 0 ; i < num_cols; i++) volumes[i] = 8;   for (int i = 0 ; i < buffer_size; i++) noises[i] = random(300,612);   hm.animate();      Wire.begin();    //clock.setDateTime(__DATE__,__TIME__);}void loop() {  if(mode == 0) sound_display();  else if(mode == 1) clock_display();  else if(mode == 2) text_display();  check_buttons();}void displayer2(){  hm.displayer();}void check_buttons(){ if(digitalRead(9) == HIGH && millis() - last_press > 250){   mode = ++mode % num_modes;   if(mode == 0) hm.animate();   if(mode == 2) hm.set_message(" Hello I'm the Heart Matrix! ");    last_press = millis(); } hm.set_scroll_wait(max(20, analogRead(0)/4)); }void text_display(){  hm.on();  }void clock_display(){  hm.on();    if (millis() - last_update > 1000){    stime = " ";        byte a_hour = clock.hour24();    String a_hour_s = String(a_hour,HEX);    int hour_int = a_hour_s.toInt();    String ampm = "am  ";    if (hour_int >= 12){      ampm = "pm  ";      hour_int -= 12;      a_hour_s = String(hour_int);    }    if (a_hour == 0 || a_hour == 12 ) stime += String(12);     else stime += a_hour_s;      stime += ":";    byte a_min = clock.minute();    if (a_min < 10 ) stime += String(0);    stime += String(a_min,HEX);    stime += ":";    byte a_sec = clock.second();    if (a_sec < 10 ) stime += String(0);    stime += String(a_sec,HEX);    hm.set_message(stime+ampm );    last_update = millis();  }}void sound_display(){   // Get a value from the electret microphone      noises[cur_index] = analogRead(mic_pin) ;   cur_index++;   if(cur_index == buffer_size) cur_index = 0;   // Control the scroll speed with a potentiometer on analog pin 0   delay_speed = max(10, (analogRead(0)/4));      // Shift the waveform over one column   if (millis() - last_shift > delay_speed){     last_shift = millis();     unsigned int avg = average(noises, buffer_size);     unsigned long var = variance(noises, buffer_size);     max_var = max(var, max_var);     min_var = min(var, min_var);     var = map(var,min_var , max_var, 0, 9);     for (int i = 1 ; i < num_cols; i++){      volumes[i-1] = volumes[i];     }     volumes[num_cols-1] = var;   }      // Write the wave form to LED display   for (int i = 0 ; i < num_cols; i++){     for (int j = 0 ; j < volumes[i]; j++){       hm.set_pixel(i, j, true);       }     for (int j = volumes[i] ; j < 8; j++){       hm.set_pixel(i, j, false);       }   }  }int average(int* array, int length){  int sum = 0;  int i;  for(i = 0; i < length ; i++){    sum += array[i];  }  int avg = sum / length ;  return avg;}unsigned long variance(int* array, int length){  long sum = 0;  long avg = average(array, length);  for(int i = 0; i < length ; i++){    sum += (array[i] - avg)*(array[i] - avg);  }  unsigned long var = sum / length;  return var;}