"use mqtt" morse code flasher

morse.ino

// Morse Code - USE MQTT!
// based on a project from 30 Arduino Projects for the Evil Genius
// thanks to Simon Monk

// Andy Piper @andypiper, Nov 2013

int ledPin = 12;

char* letters[] = {
  ".-", "-...", "-.-.", "-..", ".", "..-.", "--.", "....", "..",    // A-I
  ".---", "-.-", ".-..", "--", "-.", "---", ".--.", "--.-", ".-.",  // J-R
  "...", "-", "..-", "...-", ".--", "-..-", "-.--", "--.."          // S-Z
};

char* numbers[] = {"-----", ".----", "..---", "...--", "....-", ".....", "-....", "--...", "---..", "----."};

int dotDelay = 200;

void setup()                 
{
  pinMode(ledPin, OUTPUT);
  
  digitalWrite(ledPin, HIGH); // quick blinks to acknowledge setup
  delay(100);
  digitalWrite(ledPin, LOW);
  delay(100);
  digitalWrite(ledPin, HIGH);
  delay(100);
  digitalWrite(ledPin, LOW);
  delay(100);
  digitalWrite(ledPin, HIGH);
  delay(100);
  
  digitalWrite(ledPin, LOW); // don't want LED on immediately 
  delay(dotDelay * 20);      // before we get started
}

void loop()                    
{
  
  char ch;
  
  ch = (char)'u';
  flashSequence(letters[ch - 'a']);
  ch = (char)'s';
  flashSequence(letters[ch - 'a']);
  ch = (char)'e';
  flashSequence(letters[ch - 'a']);
  
  delay(dotDelay * 7); // gap between words

  ch = (char)'m';
  flashSequence(letters[ch - 'a']);
  ch = (char)'q';
  flashSequence(letters[ch - 'a']);
  ch = (char)'t';
  flashSequence(letters[ch - 'a']);
  ch = (char)'t';
  flashSequence(letters[ch - 'a']);

  delay(dotDelay * 14); // end message
  
}

void flashSequence(char* sequence)
{
   int i = 0;
   while (sequence[i] != NULL)
   {
       flashDotOrDash(sequence[i]);
       i++;
   }
   delay(dotDelay * 3); // gap between letters
}

void flashDotOrDash(char dotOrDash)
{
  digitalWrite(ledPin, HIGH);
  if (dotOrDash == '.')
  {
    delay(dotDelay);           
  }
  else // must be a -
  {
    delay(dotDelay * 3);           
  }
  digitalWrite(ledPin, LOW);    
  delay(dotDelay); // gap between flashes
}