HC-SR04 not only inexpensive but also practical, use a sample AVR development boar –Arduino , with a LCD screen , you can make a easy rangefinder device , which can ranging 2cm to 500cm .

HC-SR04 not only inexpensive but also practical, use a sample AVR development boar –Arduino , with a LCD screen , you can make a easy rangefinder device , which can ranging 2cm to 500cm .

Now first connect the circuit as below : With module : pin13 to Trig ; pin 12 to Echo ; VCC to VCC; GND to GND ; pin 2 to INT With LCD: RS => pin 11 RW => pin 10 EN => pin 9 D4, D5, D6, D7 => pins 7, 6, 5, 4

Download the code below :

LiquidCrystal lcd(8, 9, 4, 5, 6, 7); int pingPin = 13; int inPin = 12;

void setup() { lcd.begin(16, 2); lcd.print("testing..."); }

void loop() {

long duration, inches, cm; pinMode(pingPin, OUTPUT); digitalWrite(pingPin, LOW); delayMicroseconds(2); digitalWrite(pingPin, HIGH); delayMicroseconds(10); digitalWrite(pingPin, LOW);

pinMode(inPin, INPUT); duration = pulseIn(inPin, HIGH);

inches = microsecondsToInches(duration); cm = microsecondsToCentimeters(duration); lcd.clear(); lcd.setCursor(0, 0); lcd.print(inches); lcd.print("in, "); lcd.print(cm); lcd.print("cm");

delay(100); }

long microsecondsToInches(long microseconds) {
return microseconds / 74 / 2; }

long microsecondsToCentimeters(long microseconds) { return microseconds / 29 / 2; }

Reset the Arduino , then you can see the distance of object in front on the LCD.