Using Arduino GPL3+ for Morse Code Communication

define SIZE 26
const int ledPin=8;
const int speakerPin=12;
const int dotButton=2;
const int dashButton=7;

String morseCode=””;
String text=””;
int characterAscii=0;
int startPos=0, endPos=0;
int startPos1=0, endPos1=0;
String characterCode=””;
int dashButtonState=0;
int dotButtonState=0;

//Array of MorseCode for letters of English Language A to Z
String letters[SIZE]={

// A to I
“.-“, “-…”, “-.-.”, “-..”, “.”, “..-.”, “–.”, “….”, “..”,
// J to R
“.—“, “-.-“, “.-..”, “–“, “-.”, “—“, “.–.”, “–.-“, “.-.”,
// S to Z
“…”, “-“, “..-“, “…-“, “.–“, “-..-“, “-.–“, “–..”
};

void setup() {
// put your setup code here, to run once:
//Getting things Ready
pinMode(ledPin, OUTPUT);
pinMode(dotButton, INPUT);
pinMode(dashButton, INPUT);
Serial.begin(9600);

Serial.println(““); Serial.println(” Demonstration of Morse Code “); Serial.println(“ “);
Serial.println(“\nInstructions”);
Serial.println(“1. First Write Your Morse code”);
Serial.println(“2. When you are done Write 1 on above input box and Press Enter or click Send Button “);
Serial.println(“3. For Space between letters write 2 and Press Enter “);
Serial.println(“4. For Space between words write 3 and Press Enter “);

Serial.println(“5. Thats all Translation of Morse Code will then be Shown “);

Serial.println(“\n\nEnter Your Morse Code Here “);

}

void loop() {
// put your main code here, to run repeatedly:

while(Serial.available() > 0 )
{
int ascii=Serial.read();

  switch(ascii)
  {
    case 49: // 49 is Ascii value of 1

    Serial.print("\n");
    morseCode.concat('#');// Placeing # at the end of morseCode to simplify further processing

     Serial.print("\nYour Morse code Translation :  ");

    endPos1=morseCode.indexOf('#');

    while(endPos1 < morseCode.length() )
    {
        extractLetters(morseCode.substring(startPos1, endPos1)); // This function would extract Letter as name suggest and would convert  code to text SIMPLE!
       startPos1=endPos1+1;
       if(startPos1 == morseCode.length() )
       {
          break; 
       }
       endPos1= morseCode.indexOf('#', startPos1);
    }
    startPos1=0;
    endPos1=0;

    text=""; //  For New Translation   
    morseCode="";
    Serial.println("\n\nEnter Your Morse Code Here ");


    break;

    case 50: // 50 is Ascii value of 2

    morseCode.concat("@");
    Serial.print("@");
    delay(200);

    break;

    case 51: // 51 is Ascii value of 3

    morseCode.concat("#");
    Serial.print("#");
    delay(200);

    break;

  }

}

process();

}

void turnONLedSpeaker()
{
//Turn ON LED
digitalWrite(ledPin, HIGH);
tone(speakerPin, 4699, 300); // tone(speakerPin, frequency, duration in milliSec)

}

void process()
{

dotButtonState=digitalRead(dotButton);
dashButtonState=digitalRead(dashButton);

if(dashButtonState == HIGH)
{
turnONLedSpeaker();

morseCode.concat("-"); // Storing code in variable morseCode with the help of concatenation function
Serial.print("-");//Prints User entered Code
delay(200);

}
else if(dotButtonState == HIGH)
{
turnONLedSpeaker();

morseCode.concat(“.”);
Serial.print(“.”);
delay(200);

}
else
{
//Turn OFF LED
digitalWrite(ledPin, LOW);

}

}

char convertIntoText(String characterCode)
{
characterAscii=65;

for(int index=0; index<SIZE; index++)
{
if(characterCode == letters[index])
{
return characterAscii;
}
characterAscii++;
}

}

void extractLetters(String words)
{
words.concat(‘@’); // Placeing @ at the end of word to simplify further processing

    endPos=words.indexOf('@');


    //Loop to extracting single character morse Code from string of word        
    while( endPos<words.length() )
   {
     characterCode=words.substring(startPos, endPos);

     //Now CharacterCode will now convert in text

     text.concat(convertIntoText(characterCode));

     startPos=endPos+1;
     characterCode="";

      // if condition is just to terminate loop when our extracting single character code is complete thats all
     if(startPos == words.length() )
     {
       break;
     }

     endPos=words.indexOf('@', startPos);   

   }


    Serial.print(text);
    Serial.print(" ");
    startPos=0;
    endPos=0;
    text="";    

}