void setup()
{
 Serial.begin(115200);
 pinMode(13,OUTPUT);
}
void loop()
{
 pinMode(11,OUTPUT);
 digitalWrite(11,0);
 delayMicroseconds(2);
 digitalWrite(11,1);
 delayMicroseconds(5);
 digitalWrite(11,0);
 pinMode(12,INPUT);
 long t = pulseIn(12,1);
 float D = t/29/2;
 Serial.print(D);
 Serial.print(",");
 Serial. println(t);
 if(D < 20.0)
 {
 digitalWrite(13,1);
 delay(D*10);
 digitalWrite(13,0);
 delay(D*10);
 }
 else
 digitalWrite(13,0);
 delay(200);
}void setup()
{
 Serial.begin(115200);
 pinMode(13,OUTPUT);
}
void loop()
{
 pinMode(11,OUTPUT);
 digitalWrite(11,0);
 delayMicroseconds(2);
 digitalWrite(11,1);
 delayMicroseconds(5);
 digitalWrite(11,0);
 pinMode(12,INPUT);
 long t = pulseIn(12,1);
 float D = t/29/2;
 Serial.print(D);
 Serial.print(",");
 Serial. println(t);
 if(D < 20.0)
 {
 digitalWrite(13,1);
 delay(D*10);
 digitalWrite(13,0);
 delay(D*10);
 }
 else
 digitalWrite(13,0);
 delay(200);
}