void setup() {  
  pinMode(28, OUTPUT); //a
  pinMode(27, OUTPUT); //b
  pinMode(26, OUTPUT); //c
  pinMode(22, OUTPUT); //d
  pinMode(21, OUTPUT); //e
  pinMode(20, OUTPUT); //f
  pinMode(19, OUTPUT); //g
}

void loop() {
  digitalWrite(28,LOW);  //a
  digitalWrite(27,LOW); //b
  digitalWrite(26,HIGH);  //c
  digitalWrite(22,LOW); //d
  digitalWrite(21,LOW);  //e
  digitalWrite(20,HIGH); //f
  digitalWrite(19,LOW); //g
}