void setup() {
  Serial.begin(9600);
  for (int x = 2; x < 6; x++) pinMode(x, OUTPUT);
}


void loop() {
  for (int b = 0; b < 16; b++) {
    Serial.println(b);
    for (int z = 0; z < 4; z++) {
      digitalWrite(2, bitRead(b, 0));
      digitalWrite(3, bitRead(b, 1));
      digitalWrite(4, bitRead(b, 2));
      digitalWrite(5, bitRead(b, 3));
      delay(33); // 这里可以根据需要调整每个电阻连接的时间间隔
    }
  }
}