#define DS PB0 // Serial Input
#define STCP PB1 // Output Latch
#define SHCP PB2 // Shift Register Clock

uint8_t data[8] = {0};

void writeData(uint8_t pin_number, uint8_t pin_data) {
  data[pin_number] = pin_data;
}

void update_shiftregister() {
  digitalWrite(STCP, LOW);
  for (uint8_t i = 0, i < 8; i++) {
    digitalWrite(SHCP, HIGH);
    digitalWrite(DS, data[i]);
    digitalWrite(SHCP, LOW);
  }
  digitalWrite(STCP, HIGH);
}

void setup() {
  // Shift Register Initialization
  pinMode(DS, OUTPUT);
  pinMode(STCP, OUTPUT);
  pinMode(SHCP, OUTPUT);

  digitalWrite(SHCP, LOW);
}

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

}