#define DATA 4
#define CLOCK 5
#define LATCH 6

void setup() {
  pinMode(DATA, OUTPUT);
  pinMode(CLOCK, OUTPUT);
  pinMode(LATCH, OUTPUT);
}

void sendByte(uint8_t val) {
  digitalWrite(LATCH, LOW);
  shiftOut(DATA, CLOCK, MSBFIRST, val);
  digitalWrite(LATCH, HIGH);
}

void loop() {
  sendByte(0b10101010);
  delay(1000);
  sendByte(0b01010101);
  delay(1000);
}