int trig =8;
int echo = 9;
int led = 3;
void setup()
{                                                                            
  Serial.begin(9600);
  pinMode(trig,OUTPUT);
  pinMode(echo,INPUT);
  pinMode(led,OUTPUT);
}
void loop()
{
  digitalWrite(trig,LOW);
  digitalWrite(echo,LOW);
  delayMicroseconds(2);
  digitalWrite(trig,HIGH);
  delayMicroseconds(10);
  digitalWrite(trig,LOW);
  unsigned long duration = pulseln(echo,HIGH);
  float distance = duration/29.0/2.0;
  Serial.print(distance);
  Serial.print("cm");
  if(distance<10)
  {
    digitalWrite(led,HIGH);
  }
  delay(200);
}모가 틀린거죠?