網頁文章 javax.portlet.title.56

 const int pingPin =13;

 
void setup() {
  Serial.begin(9600);
}
 
void loop()
{
long duration, inches, cm;
 
pinMode(2, OUTPUT);
pinMode(4, OUTPUT);
pinMode(6, OUTPUT);
pinMode(pingPin, OUTPUT);
digitalWrite(pingPin, LOW);
delayMicroseconds(5);
digitalWrite(pingPin, HIGH);
delayMicroseconds(10);
digitalWrite(pingPin, LOW);
 
 
pinMode(12, INPUT);
duration = pulseIn(12, HIGH);
inches = microsecondsToInches(duration);    //duration/74/2
cm = microsecondsToCentimeters(duration);    //duration/29/2
 
 
 
Serial.print(inches);
Serial.print("in, ");
Serial.print(cm);
Serial.print("cm");
Serial.println();
 
if (cm < 10){    
digitalWrite(2, HIGH);
}else{digitalWrite(2, LOW);}
 
if (cm > 10 && cm < 20)
digitalWrite(4, HIGH);
}else{digitalWrite(4, LOW);}
 
if (cm > 20)
digitalWrite(6, HIGH);
}else{digitalWrite(6, LOW);}
 
delay(100);
 
}
 
long microsecondsToInches(long microseconds)
{
    return microseconds / 74 / 2;
}
 
long microsecondsToCentimeters(long microseconds)
{
    return microseconds / 29 / 2;
}