/*
 * Wather level and pomp controler ESP32
 * Manual and automatic level control
 *
 * Narcyz Wojcik 2024
 *
 * more infos you can find on https://esp32io.com/
 */


const int TRIG_PIN = 23; // ESP32 pin GPIO23 connected to Ultrasonic Sensor's TRIG pin
const int ECHO_PIN = 22; // ESP32 pin GPIO22 connected to Ultrasonic Sensor's ECHO pin

const int RELAY_PIN = 21;

float duration_us, distance_cm;

void setup() {
  // begin serial port
  Serial.begin (9600);

  // configure the trigger pin to output mode
  pinMode(TRIG_PIN, OUTPUT);
  // configure the echo pin to input mode
  pinMode(ECHO_PIN, INPUT);

  // configure the relay_pin to output mode
  pinMode(RELAY_PIN, OUTPUT);
  digitalWrite(RELAY_PIN, LOW);
  delay(500);
}

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;

  // print the value to Serial Monitor
  Serial.print("distance: ");
  Serial.print(distance_cm);
  Serial.println(" cm");

  if (distance_cm < 100) {
    digitalWrite(RELAY_PIN, HIGH);
  }
  if (distance_cm > 100 ) {
    digitalWrite(RELAY_PIN, LOW);
  }
  
  delay(500);
}