/*
  Arduino ASCII- Braille Translator
  by Cesare Brizio | CC by-sa-nc
  this sketch is in the public domain

  Version 1.0 - 29 June 2019
  ------------------------------
  This sketch will use six small solenoids/electromagnets arranged in
  three rows of two columns to operate a Braille dot matrix.
  Any ASCII character sent to Arduino via COM port will be "translated"
  in a timed sequence of Braille symbols by configuring, one character 
  at a time, the dot matrix, so that the "dots" (solenoids) corresponding
  to the current ASCII character are raised for 500 msec before passing to
  the subsequent character. 
  When an un-translatable character is sent, a short buzz is emitted.

  ==== DOT NUMBERING ====
  Dots are not numbered according to the Braille convention, but are
  conventionally numbered from left to right, then from top to bottom:
  1  2
  3  4
  5  6
  As an example, showing letter "b" (asterisk represent an high dot):
  *-
  *-
  --
  will require raising dots number 1 and 3


  ==== DOT CONFIGURATION ====
  Dot configuration will be stored as a series of six binary values. As an example, 
  according to the preceding explanation, the configuration for "b" is 101000.
  As long as configurations contain just 6 bits of information, they can be stored
  in a single char that, translated bitwise (least significant bit at right), corresponds 
  to the needed configuration.
  So, 101000 (configuration for "b"), corresponding to DEC 40 and HEX 28, will be
  represented by ASCII character "(".
  Summarizing, considering that ascii code for "b" is 98D (62H) I will say that 
  myBrailleDots[98] = 40; 
  that is equivalent to
  myBrailleDots[98] = '('; 
  meaning that the binary sextet corresponding to letter "b" is 101000.
 
  When needed, a bitwise AND with increasing powers of two (from 1 to 32) will reveal 
  which dots shall be raised: this is accomplished by iterating through a 6 bit mask:
   
  Some simplifications will be applied, e.g.:
  a) the multi-letter Braille glyphs (ch, ing, for, ar, th and others)
  b) number prefix (010111), 
  c) letter prefix (000101), 
  d) uppercase prefix (000001) and other prefixes
  will not be implemented in this version, but this sketch can
  be quite easily implemented with the needed modifications.
*/  

// Declare a char array with one index for every possible ASCII byte / character
byte myBrailleDots[255];
int firstOutputPin = 2; // pin corresponding to least significant bit
int buzzerPin = 8; // Buzzer on pin 8
byte matrixPoints = 0; // byte that will store the point matrix configuration
                       // for a specific ASCII character
byte inByte;
byte mask = 1; //our bitmask

void setup() {
  // Temporarily assign 99 to every possible ASCII byte/character
  // All the characters in the input string will decode to "99" by default
  for (int i = 0; i < 256; i = i + 1) {
     myBrailleDots[i] = 99;
  }

  // Now, only for the ASCII characters with a corresponding Braille character.
  // assign the corresponding Braille Dot configuration
  myBrailleDots[32] = 0;  // blank is 000000
  myBrailleDots[33] = 14;  // exlamation mark is 001110
  myBrailleDots[34] = 7;  // double quote is 000111
  myBrailleDots[34] = 2;  // single quote is 000010
  myBrailleDots[40] = 15;  // left parenthesis is 001111
  myBrailleDots[41] = 15;  // right parenthesis is 001111
  myBrailleDots[44] = 8;  // comma is 001000
  myBrailleDots[46] = 13;  // period is 001101
  myBrailleDots[48] = 28; // 0 is 011100
  myBrailleDots[49] = 32; // 1 is 100000
  myBrailleDots[50] = 40; // 2 is 101000
  myBrailleDots[51] = 48; // 3 is 110000
  myBrailleDots[52] = 52; // 4 is 110100
  myBrailleDots[53] = 36; // 5 is 100100
  myBrailleDots[54] = 56; // 6 is 111000
  myBrailleDots[55] = 60; // 7 is 111100
  myBrailleDots[56] = 44; // 8 is 101100
  myBrailleDots[57] = 24; // 9 is 011000
  myBrailleDots[58] = 12; // colon is 001100
  myBrailleDots[59] = 10; // semicolon is 001010
  myBrailleDots[63] = 11; // question mark is 001011
  myBrailleDots[65] = 32; // A is 100000
  myBrailleDots[66] = 40; // B is 101000
  myBrailleDots[67] = 48; // C is 110000
  myBrailleDots[68] = 52; // D is 110100
  myBrailleDots[69] = 36; // E is 100100
  myBrailleDots[70] = 56; // F is 111000
  myBrailleDots[71] = 60; // G is 111100
  myBrailleDots[72] = 44; // H is 101100
  myBrailleDots[73] = 24; // I is 011000
  myBrailleDots[74] = 28; // J is 011100
  myBrailleDots[75] = 34; // K is 100010
  myBrailleDots[76] = 42; // L is 101010
  myBrailleDots[77] = 50; // M is 110010
  myBrailleDots[78] = 54; // N is 110110
  myBrailleDots[79] = 38; // O is 100110
  myBrailleDots[80] = 58; // P is 111010
  myBrailleDots[81] = 62; // Q is 111110
  myBrailleDots[82] = 46; // R is 101110
  myBrailleDots[83] = 26; // S is 011010
  myBrailleDots[84] = 30; // T is 011110
  myBrailleDots[85] = 35; // U is 100011
  myBrailleDots[86] = 43; // V is 101011
  myBrailleDots[87] = 29; // W is 011101
  myBrailleDots[88] = 51; // X is 110011
  myBrailleDots[89] = 55; // Y is 110111
  myBrailleDots[90] = 39; // Z is 100111
  myBrailleDots[97] = 32; // A is 100000
  myBrailleDots[98] = 40; // B is 101000
  myBrailleDots[99] = 48; // C is 110000
  myBrailleDots[100] = 52; // D is 110100
  myBrailleDots[101] = 36; // E is 100100
  myBrailleDots[102] = 56; // F is 111000
  myBrailleDots[103] = 60; // G is 111100
  myBrailleDots[104] = 44; // H is 101100
  myBrailleDots[105] = 24; // I is 011000
  myBrailleDots[106] = 28; // J is 011100
  myBrailleDots[107] = 34; // K is 100010
  myBrailleDots[108] = 42; // L is 101010
  myBrailleDots[109] = 50; // M is 110010
  myBrailleDots[110] = 54; // N is 110110
  myBrailleDots[111] = 38; // O is 100110
  myBrailleDots[112] = 58; // P is 111010
  myBrailleDots[113] = 62; // Q is 111110
  myBrailleDots[114] = 46; // R is 101110
  myBrailleDots[115] = 26; // S is 011010
  myBrailleDots[116] = 30; // T is 011110
  myBrailleDots[117] = 35; // U is 100011
  myBrailleDots[118] = 43; // V is 101011
  myBrailleDots[119] = 29; // W is 011101
  myBrailleDots[120] = 51; // X is 110011
  myBrailleDots[121] = 55; // Y is 110111
  myBrailleDots[122] = 39; // Z is 100111
  pinMode(buzzerPin, OUTPUT);
  pinMode(2, OUTPUT);
  pinMode(3, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(7, OUTPUT);
  Serial.begin(9600); 
  Serial.println("ASCII - Braille Arduino Converter");
  Serial.println("LED test - begin");
  digitalWrite(2,HIGH);
  digitalWrite(3,HIGH);
  digitalWrite(4,HIGH);
  digitalWrite(5,HIGH);
  digitalWrite(6,HIGH);
  digitalWrite(7,HIGH);
  delay(3000);
  digitalWrite(2,LOW);
  digitalWrite(3,LOW);
  digitalWrite(4,LOW);
  digitalWrite(5,LOW);
  digitalWrite(6,LOW);
  digitalWrite(7,LOW);
  Serial.println("LED test - end");
  Serial.println("Type some character: it will be transmitted to Arduino and displayed on a Braille 2 x 3 matrix");
}


void loop() {
   // Braille print data only when you receive data:
   if (Serial.available() > 0) {
      // read the incoming byte:
      inByte = Serial.read();
      // say what you got:
      Serial.print("Received (inByte): ");
      Serial.println(inByte);
      // Translate inByte in matrix points
      Serial.print("Matrix points variable (myBrailleDots[inByte]): ");
      Serial.println(myBrailleDots[inByte]);

      // Braille print only admissible characters
      // the unadmissible ones decode to 99
      if (myBrailleDots[inByte] == 99)   // if unadmissible
      {
         Serial.println("Not a translatable character");
         digitalWrite(buzzerPin,HIGH); // buzz
         delay(250); 
         digitalWrite(buzzerPin,LOW); // stop buzzing
      }
      else{ 
              int thisPin = 2;
              for (mask = 000001; mask<64; mask <<= 1) { 
                  Serial.print("thisPin = ");
                  Serial.println(thisPin); 
                  if (myBrailleDots[inByte] & mask){ // if bitwise AND resolves to true
                     Serial.print("AND successful, put pin on!");
                     Serial.println(mask);  
                     digitalWrite(thisPin,HIGH);               
                  }
                  else{ //if bitwise and resolves to false
                     Serial.print("AND unsuccessful, put pin off!");
                     Serial.println(mask);  
                     digitalWrite(thisPin,LOW);
                  }
              thisPin = thisPin + 1;   
              }
      } 
      delay(3000); // allow 3 sec before passing to next character
   }
}