Example Code for Arduino-Distance Measurement

Wiring Diagram

Sample Code

#include "Arduino.h"

/*
 Trig:  Measurement trigger pin - Low level pulse over 50us triggers one distance measurement.
 Holding this pin LOW will repeats the measurement every 100ms.
 */
#define  TRIGGER   2

/*
 OUT: analog output 0.33mV equals 1mm
 */
#define  ANALOG    1

void setup()
{
  pinMode(TRIGGER, OUTPUT);
  digitalWrite(TRIGGER, HIGH);
  Serial.begin(9600);
}
void loop()
{
  // generate the pulse to trigger the sensor
  digitalWrite(TRIGGER, LOW);
  delayMicroseconds(50);
  digitalWrite(TRIGGER, HIGH);
  delayMicroseconds(50);

  unsigned int distance = analogRead(ANALOG);  //read the analog pin
  distance = (unsigned int)(((unsigned long)distance * 5000)/1024);  //change from analog value to voltage
  distance = (unsigned int)((float)distance / 0.33f); //0.33mV equals to 1mm,
  //distance = (unsigned int)((float)distance / 0.2129f); //For new version, 0.2129mV equals to 1mm. 

  Serial.print("distance:");
  Serial.print(distance);
  Serial.println("mm");
  delay(500);
}