int d = 3, c = 5, l = 4;
byte data = 0;
char str[8] = "10100000";

void setup() {
  // put your setup code here, to run once:
  pinMode(d, OUTPUT);
  pinMode(c, OUTPUT);
  pinMode(l, OUTPUT);

}

void loop() {
  // put your main code here, to run repeatedly:
  f1();

}

void shiftWrite(int pin, boolean state) {
  bitWrite(data, pin, state);
  shiftOut(d, c, MSBFIRST, data);
  digitalWrite(l, HIGH);
  digitalWrite(l, LOW);
}

void f1() {
  int i;
  for (i = 0 ; i < 8 ; i++) {
    if (str[i] == '0') {
      shiftWrite(i, LOW);
    } else {
      shiftWrite(i, HIGH);
    }
  }
}