const int latchPin = 8; //ST_CP or RCLK
const int clockPin = 12; //SH_CP or SRCLK
const int dataPin = 11; //DS or SER

byte seven_seg_digits[10][7] = { 
   { 1,1,1,1,1,1,0 },  // = 0
   { 0,1,1,0,0,0,0 },  // = 1
   { 1,1,0,1,1,0,1 },  // = 2
   { 1,1,1,1,0,0,1 },  // = 3
   { 0,1,1,0,0,1,1 },  // = 4
   { 1,0,1,1,0,1,1 },  // = 5
   { 1,0,1,1,1,1,1 },  // = 6
   { 1,1,1,0,0,0,0 },  // = 7
   { 1,1,1,1,1,1,1 },  // = 8
   { 1,1,1,0,0,1,1 }   // = 9
};

int digits[10] = {
  126, 48, 109, 121, 51, 91, 95, 112, 127, 
}


void writeNumber(int character) {
  /* The shift register shifts out bits to the ADO lines. In binary:
   * 1110 = Sensor on Q0(QA) ~(2^0) = ~1 = 1110 in binary
   * 1101 = Sensor on Q1(QB) ~(2^1) = ~2 = 1101 in binary
   * '~' = not
   */
  //int data = (int) 1 << (sensorNumber - 1); // Shift register serial data input.

  digitalWrite(latchPin, LOW); // Hold low for as long as you are transmitting data.
  shiftOutBits(dataPin, clockPin, character); // Shift out the bits into the shift register; negate data. (0001 = 1000)
  digitalWrite(latchPin, HIGH); // Ends transmission of data.
}

void shiftOutBits(int myDataPin, int myClockPin, int number) {
  // This shifts 8 bits out MSB first.
  
  // Setup Varaibles
  int pinState;

  pinMode(myClockPin, OUTPUT);
  pinMode(myDataPin, OUTPUT);

  // Clear everything out in case to prepare shift register.
  digitalWrite(myDataPin, 0);
  digitalWrite(myClockPin, 0);

  // For each bit in the byte myDataOut.
  for (int i = 7; i >= 0; i--) {
    digitalWrite(myClockPin, 0);

    pinState = 1 - seven_seg_digits[number][i];
    digitalWrite(myDataPin, pinState); // Sets the pin to HIGH or LOW depending on pinState.
    digitalWrite(myClockPin, 1); // Register shifts on HIGH of myClockPin.
    digitalWrite(myDataPin, 0); // Stop sending on myDataPin.
  }
  digitalWrite(myClockPin, 0); // Stop shifting.
}

void setup() {
  writeNumber(5);
}

void loop() {
  return;
}