Wemos buzzer shield example

In this example we look at another Wemos mini shield, this time its the buzzer_shield which as its name suggests is a basic buzzer. Its an MLT_8540.

The product page is https://wiki.wemos.cc/products:d1_mini_shields:buzzer_shield

Code

This example plays a few notes from a popular song

[codesyntax lang=”cpp”]

int buzzerPin=D5; //Buzzer control port, default D5
const int songLength = 18;
char notes[] = "cdfda ag cdfdg gf ";
int beats[] = {1,1,1,1,1,1,4,4,2,1,1,1,1,1,1,4,4,2};
int tempo = 150;


void setup() 
{
  pinMode(buzzerPin, OUTPUT);
}


void loop() 
{
  int i, duration;
 
  for (i = 0; i < songLength; i++) // step through the song arrays
  {
    duration = beats[i] * tempo;  // length of note/rest in ms
    
    if (notes[i] == ' ')          // is this a rest? 
    {
      delay(duration);            // then pause for a moment
    }
    else                          // otherwise, play the note
    {
      tone(buzzerPin, frequency(notes[i]), duration);
      delay(duration); // wait for tone to finish
    }
    delay(tempo/10);              // brief pause between notes
  }
  
  while(true){}

}


int frequency(char note) 
{

  int i;
  const int numNotes = 8;  // number of notes we're storing
  char names[] = { 'c', 'd', 'e', 'f', 'g', 'a', 'b', 'C' };
  int frequencies[] = {262, 294, 330, 349, 392, 440, 494, 523};
  

  for (i = 0; i < numNotes; i++)  // Step through the notes
  {
    if (names[i] == note)         // Is this the one?
    {
      return(frequencies[i]);     // Yes! Return the frequency
    }
  }
  return(0); 
}

[/codesyntax]