/*
* This ESP32 code is created by Fajar Himawan
*
* This ESP32 code is released in the public domain
*
* For more detail (instruction and wiring diagram), contact me : 08970355799
*/
#include <ESP32Servo.h>
#define TRIG_PIN 23 // ESP32 pin GIOP23 connected to Ultrasonic Sensor's TRIG pin
#define ECHO_PIN 22 // ESP32 pin GIOP22 connected to Ultrasonic Sensor's ECHO pin
#define SERVO_PIN 26 // ESP32 pin GIOP26 connected to Servo Motor's pin
#define DISTANCE_THRESHOLD 10 // centimeters
Servo servo; // create servo object to control a servo
// variables will change:
float duration_us, distance_cm;
void setup() {
Serial.begin (9600); // initialize serial port
pinMode(TRIG_PIN, OUTPUT); // set ESP32 pin to output mode
pinMode(ECHO_PIN, INPUT); // set ESP32 pin to input mode
servo.attach(SERVO_PIN); // attaches the servo on pin 9 to the servo object
servo.write(0);
}
void loop() {
// generate 10-microsecond pulse to TRIG pin
digitalWrite(TRIG_PIN, HIGH);
delayMicroseconds(10);
digitalWrite(TRIG_PIN, LOW);
// measure duration of pulse from ECHO pin
duration_us = pulseIn(ECHO_PIN, HIGH);
// calculate the distance
distance_cm = 0.017 * duration_us;
if (distance_cm < DISTANCE_THRESHOLD)
servo.write(0); // rotate servo motor to 90 degree
else
servo.write(90); // rotate servo motor to 0 degree
// print the value to Serial Monitor
Serial.print("distance: ");
Serial.print(distance_cm);
Serial.println(" cm");
delay(500);
}