arduino-morse-code.ino

// author: mert akengin

short led = 13;
unsigned morse[256];

typedef enum time
{
  unit = 100,
  sh = 1*unit,
  ln = 3*unit,
  br = (int)(2*unit),
  lt = 3*unit,
  sp = 7*unit,
  msize = 6
} ledtime;

void init_morse()
{
  for(int i=0;i<256;i++)
    morse[i] = 0;
  morse['A'] = 1*3 + 2*9 + 0*27 + 0*81;
  morse['B'] = 2*3 + 1*9 + 1*27 + 1*81;
  morse['C'] = 2*3 + 1*9 + 2*27 + 1*81;
  morse['D'] = 2*3 + 1*9 + 1*27 + 0*81;
  morse['E'] = 1*3 + 0*9 + 0*27 + 0*81;
  morse['F'] = 1*3 + 1*9 + 2*27 + 1*81;
  morse['G'] = 2*3 + 2*9 + 1*27 + 0*81;
  morse['H'] = 1*3 + 1*9 + 1*27 + 1*81;
  morse['I'] = 1*3 + 1*9 + 0*27 + 0*81;
  morse['J'] = 1*3 + 2*9 + 2*27 + 2*81;
  morse['K'] = 2*3 + 1*9 + 2*27 + 0*81;
  morse['L'] = 1*3 + 2*9 + 1*27 + 1*81;
  morse['M'] = 2*3 + 2*9 + 0*27 + 0*81;
  morse['N'] = 2*3 + 1*9 + 0*27 + 0*81;
  morse['O'] = 2*3 + 2*9 + 2*27 + 0*81;
  morse['P'] = 1*3 + 2*9 + 2*27 + 1*81;
  morse['Q'] = 2*3 + 2*9 + 1*27 + 2*81;
  morse['R'] = 1*3 + 2*9 + 1*27 + 0*81;
  morse['S'] = 1*3 + 1*9 + 1*27 + 0*81;
  morse['T'] = 2*3 + 0*9 + 0*27 + 0*81;
  morse['U'] = 1*3 + 1*9 + 2*27 + 0*81;
  morse['V'] = 1*3 + 1*9 + 1*27 + 2*81;
  morse['W'] = 1*3 + 2*9 + 2*27 + 0*81;
  morse['X'] = 2*3 + 1*9 + 1*27 + 2*81;
  morse['Y'] = 2*3 + 1*9 + 2*27 + 2*81;
  morse['Z'] = 2*3 + 2*9 + 1*27 + 1*81;
  morse['0'] = 2*3 + 2*9 + 2*27 + 2*81 + 2*243;
  morse['1'] = 1*3 + 2*9 + 2*27 + 2*81 + 2*243;
  morse['2'] = 1*3 + 1*9 + 2*27 + 2*81 + 2*243;
  morse['3'] = 1*3 + 1*9 + 1*27 + 2*81 + 2*243;
  morse['4'] = 1*3 + 1*9 + 1*27 + 1*81 + 2*243;
  morse['5'] = 1*3 + 1*9 + 1*27 + 1*81 + 1*243;
  morse['6'] = 2*3 + 1*9 + 1*27 + 1*81 + 1*243;
  morse['7'] = 2*3 + 2*9 + 1*27 + 1*81 + 1*243;
  morse['8'] = 2*3 + 2*9 + 2*27 + 1*81 + 1*243;
  morse['9'] = 2*3 + 2*9 + 2*27 + 2*81 + 1*243;
  morse['/'] = 2*3 + 1*9 + 1*27 + 2*81 + 1*243;
  morse['('] = 2*3 + 1*9 + 2*27 + 2*81 + 1*243;
  morse['&'] = 1*3 + 2*9 + 1*27 + 1*81 + 1*243;
  morse['='] = 2*3 + 1*9 + 1*27 + 1*81 + 2*243;
  morse['+'] = 1*3 + 2*9 + 1*27 + 2*81 + 1*243;
  morse['.'] = 1*3 + 2*9 + 1*27 + 2*81 + 1*243 + 2*729;
  morse[','] = 2*3 + 2*9 + 1*27 + 1*81 + 2*243 + 2*729;
  morse['?'] = 1*3 + 1*9 + 2*27 + 2*81 + 1*243 + 1*729;
  morse['`'] = 1*3 + 2*9 + 2*27 + 2*81 + 2*243 + 1*729;
  morse['!'] = 2*3 + 1*9 + 2*27 + 1*81 + 2*243 + 2*729;
  morse[')'] = 2*3 + 1*9 + 2*27 + 2*81 + 1*243 + 2*729;
  morse[':'] = 2*3 + 2*9 + 2*27 + 1*81 + 1*243 + 1*729;
  morse[';'] = 2*3 + 1*9 + 2*27 + 1*81 + 2*243 + 1*729;
  morse['-'] = 2*3 + 1*9 + 1*27 + 1*81 + 1*243 + 2*729;
  morse['_'] = 1*3 + 1*9 + 2*27 + 2*81 + 1*243 + 2*729;
  morse['"'] = 1*3 + 2*9 + 1*27 + 1*81 + 2*243 + 1*729;
  morse['@'] = 1*3 + 2*9 + 2*27 + 1*81 + 2*243 + 1*729;
  morse['\''] = 1*3 + 2*9 + 2*27 + 2*81 + 2*243 + 1*729;
  return;
}
void ledshort()
{
  digitalWrite(led,HIGH);
  delay(sh);
  digitalWrite(led,LOW);
  return;
}
void ledlong()
{
  digitalWrite(led,HIGH);
  delay(ln);
  digitalWrite(led,LOW);
  return;
}
void letter(char c)
{
  switch(c)
  {
    case '\0':
    case '\n':
      Serial.write("\n");
    case '\r':
      Serial.write("\r");
    case ' ':
      if(c == ' ')
        Serial.write(" ");
      delay(sp);
      return;
  }
  if(c < '!' || c > 'z')
    return;
  if(c >= 'a' && c <= 'z')
    c = c-('a'-'A');
  short dig[msize],div[msize+1]={3,9,27,81,243,729,2187};
  for(int i=msize-1;i>0;i--)
    dig[i-1] = (morse[c]%div[i])/div[i-1];
  Serial.write(c);
  for(int i=0;i<msize-1;i++)
  {
    switch(dig[i])
    {
      case 1:
        ledshort();
        break;
      case 2:
        ledlong();
        break;
      default:
        delay(lt);
        return;
    }
    delay(br);
  }
}

void setup()
{
  Serial.begin(9600);
  pinMode(led,OUTPUT);
  init_morse();
}
String input;
void loop()
{
  while(!Serial.available());
  input = Serial.readString();
  //Serial.write(" ");
  for(int i=0;i<input.length();i++)
    letter(input[i]);
  Serial.write("\n");
  delay(25*unit);
}