ian-arduino/4button-keyboard.ino

/*THE WORKING VERSION OF THE 4 BUTTON KEYBOARD

LAYOUT

RedWire->|
         |
____________
| L1   L2  |
|          |
|          |
| L3   L4  |
|          |
------------
    |  |
    |  |
    ----
L1 = buttonState3, b4, v1, var + 5
L2 = buttonState1, b2, v3, var - 1
L3 = buttonState, b1, v2, var + 1
L3 = buttonState2, b3, v4, var + 10


*/

//Ints for counting multipress
int v1 = 0;
int v2 = 0;
int v3 = 0;
int v4 = 0;

//ints for button pins (only b1 - 4 are in use)
const int b1 = 2;
const int b2 = 3;
const int b3 = 4;
const int b4 = 5;
const int b5 = 6;
const int b6 = 7;

//int for counting number and submit
int var = 0;
int subvar = 0;

//Not sure what this does, but don't want to delete it
int ptrue = 0;

//ints for counting button presses
int buttonState = 0;
int lastButtonState = 0;
int buttonState1 = 0;
int lastButtonState1 = 0;
int buttonState2 = 0;
int lastButtonState2 = 0;
int buttonState3 = 0;
int lastButtonState3 = 0;

//ints for debouncing each button
long debounceDelay = 50;
long lastDebounceTime = 0;
int state = 0;
long lastDebounceTime1 = 0;
int state1 = 0;
long lastDebounceTime2 = 0;
int state2 = 0;
long lastDebounceTime3 = 0;
int state3 = 0;

/* the pins are set up as inputs and then set high,
so that when the button is grounded it will notice it
and count it as a button press.  this way, there are
no resistors needed for the curcuit.

The button should be connected from the pin, to the
button, to ground, like this:

PIN# --> Pin1 of button |--| -- Ground
                         ^         
                 Button  |
                       
*/
void setup() {
  Serial.begin(9600);
  Serial.println("Begin Typing");
  pinMode(b1, INPUT);
  pinMode(b2, INPUT);
  pinMode(b3, INPUT);
  pinMode(b4, INPUT);
  pinMode(b5, INPUT);
  pinMode(b6, INPUT);
  digitalWrite(b1, HIGH);
  digitalWrite(b2, HIGH);
  digitalWrite(b3, HIGH);
  digitalWrite(b4, HIGH);
  digitalWrite(b5, HIGH);
  digitalWrite(b6, HIGH);
}

void loop() {

  
  
  state3 = digitalRead(b4); //read if grounded or not
  if ((millis() - lastDebounceTime3) > debounceDelay) { //if the button has not been pressed within debouncetime, do...
    buttonState3 = digitalRead(b4);
    if (buttonState3 != lastButtonState3) {  //if the button is different from before (it was pessed) do...
      if (buttonState3 == HIGH) { //if the switch was released, do...
        lastDebounceTime3 = millis();
        v1 = 0;  //reset the multipress counter, so it does not count it as a press after you release the button
      } 
      else {  //if switch pressed, do...
        var = var + 5;  //setting for what the button does
        lastDebounceTime3 = millis(); //reset the last debounce
        v1 = 1;  //set multipress variable to one, or, pressed
      }
    }
  }

  //the same goes for this
  state = digitalRead(b1);
  if ((millis() - lastDebounceTime) > debounceDelay) {
    buttonState = digitalRead(b1);
    if (buttonState != lastButtonState) {
      if (buttonState == HIGH) {
        lastDebounceTime = millis();
        v2 = 0;
      } 
      else {
        var = var + 1;
        lastDebounceTime = millis();
        v2 = 1;
      }
    }
  }

  //and this
  state1 = digitalRead(b2);
  if ((millis() - lastDebounceTime1) > debounceDelay) {
    buttonState1 = digitalRead(b2);
    if (buttonState1 != lastButtonState1) {
      if (buttonState1 == HIGH) {
        lastDebounceTime1 = millis();
        v3 = 0;
      } 
      else {
        var = var - 1;
        lastDebounceTime1 = millis();
        v3 = 1;
      }
    }
  }

  //... and this
  state2 = digitalRead(b3);
  if ((millis() - lastDebounceTime2) > debounceDelay) {
    buttonState2 = digitalRead(b3);
    if (buttonState2 != lastButtonState2) {
      if (buttonState2 == HIGH) {
        lastDebounceTime2 = millis();
        v4 = 0;
      } 
      else {
        var = var + 10;
        lastDebounceTime2 = millis();
        v4 = 1;
      }
    }
  }


// this whole section controls what letters correspond to what numbers,
// and when to send the letter out
  if (var == 1) { //if the variable is 1,
    if (subvar == 1) { //and, if you pressed the submit button,
      Serial.print('A'); //print the letter 'A' (A is the first letter in the alphabet)
      subvar = 0; //reset the submit button so it doesnt happen forever
      var = 0; //reset the variable, so you can count to the next word.
    }
  }
  
//the same goes for all the code below, untill the next comment.

  if (var == 2) {
    if (subvar == 1) {
      Serial.print('B');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 3) {
    if (subvar == 1) {
      Serial.print('C');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 4) {
    if (subvar == 1) {
      Serial.print('D');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 5) {
    if (subvar == 1) {
      Serial.print('E');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 6) {
    if (subvar == 1) {
      Serial.print('F');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 7) {
    if (subvar == 1) {
      Serial.print('G');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 8) {
    if (subvar == 1) {
      Serial.print('H');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 9) {
    if (subvar == 1) {
      Serial.print('I');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 10) {
    if (subvar == 1) {
      Serial.print('J');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 11) {
    if (subvar == 1) {
      Serial.print('K');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 12) {
    if (subvar == 1) {
      Serial.print('L');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 13) {
    if (subvar == 1) {
      Serial.print('M');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 14) {
    if (subvar == 1) {
      Serial.print('N');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 15) {
    if (subvar == 1) {
      Serial.print('O');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 16) {
    if (subvar == 1) {
      Serial.print('P');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 17) {
    if (subvar == 1) {
      Serial.print('Q');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 18) {
    if (subvar == 1) {
      Serial.print('R');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 19) {
    if (subvar == 1) {
      Serial.print('S');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 20) {
    if (subvar == 1) {
      Serial.print('T');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 21) {
    if (subvar == 1) {
      Serial.print('U');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 22) {
    if (subvar == 1) {
      Serial.print('V');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 23) {
    if (subvar == 1) {
      Serial.print('W');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 24) {
    if (subvar == 1) {
      Serial.print('X');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 25) {
    if (subvar == 1) {
      Serial.print('Y');
      subvar = 0;
      var = 0;
    }
  }
  if (var == 26) {
    if (subvar == 1) {
      Serial.print('Z');
      subvar = 0;
      var = 0;
    }
  }

// i know everything above could've been done with a map, but, i didn't do it like that.

//this next code part control all the multipress.


  if (v1 == 1) {  //if one of the two buttons in the multipress section was pressed, 
    if (v3 == 1) { //and the second button in the multipress section was pressed, 
      subvar = 1;  //do what you want that multipres section to do.  In this case, it was
      //presss the top two buttons to submit the number.
      v1 = 0; //reset multipress button stats
      v3 = 0; //ya, again
      var = var - 5;  //take into account what would normall happen to the variable.
      //the top two button can add + 5 and - 1, so doing - 5 and + 1 will reset the 
      //variable to what it would normally be.
      var = var + 1; //the same here too
    }
  }
  
  //the same goes for the below code, but with different buttons for 
  //multipress, and different actions based on that
  
  if (v2 == 1) {
    if (v4 == 1) {
      Serial.print(" ");
      v2 = 0;
      v4 = 0;
      var = var + 1;
      var = - 5;
    }
  }  

if (v3 == 1) {
    if (v4 == 1) {
      Serial.println("");
      v3 = 0;
      v4 = 0;
      var = var + 1;
      var = var - 10;
    }
  }  

if (v1 == 1) {
    if (v2 == 1) {
      Serial.print(".");
      v1 = 0;
      v2 = 0;
      var = var - 1;
      var = var - 5;
    }
  }  


  //reset the button states.   not sure if i still need these, but dont want to risk deleting them.
  //
  lastButtonState = buttonState;
  lastButtonState1 = buttonState1;
  lastButtonState2 = buttonState2;
  lastButtonState3 = buttonState3;
}