// #define trigpin 13
// #define echopin 12

// void setup() {
//   pinMode(trigpin, OUTPUT);
//   pinMode(echopin, INPUT);
// }

// // the loop function runs over and over again forever
// void loop() {
//   digitalWrite(LED_BUILTIN, HIGH);   // turn the LED on (HIGH is the voltage level)
//   delay(500);              // wait for a second
//   digitalWrite(LED_BUILTIN, LOW);    // turn the LED off by making the voltage LOW
//   delay(500);              // wait for a second
// }
/*
   Created by ArduinoGetStarted, https://arduinogetstarted.com

   Arduino - Ultrasonic Sensor HC-SR04

   Wiring: Ultrasonic Sensor -> Arduino:
   - VCC  -> 5VDC
   - TRIG -> Pin 9
   - ECHO -> Pin 8
   - GND  -> GND

   Tutorial is available here: https://arduinogetstarted.com/tutorials/arduino-ultrasonic-sensor
*/

int trigPin = 13;    // TRIG pin
// int trigPins2 = 11;    // TRIG pin
int echoPins1 = 12;    // ECHO pin
int echoPins2 = 11;    // ECHO pin

float duration_us_s1,duration_us_s2, distance_cm_s1, distance_cm_s2;

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

  // configure the trigger pin to output mode
  pinMode(trigPin, OUTPUT);
  // configure the echo pin to input mode
  pinMode(echoPins1, INPUT);
  pinMode(echoPins2, INPUT);
}

void loop() {
  // generate 10-microsecond pulse to TRIG pin
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  // measure duration of pulse from ECHO pin
  duration_us_s1 = pulseIn(echoPins1, HIGH);
  duration_us_s2 = pulseIn(echoPins2, HIGH);

  // calculate the distance
  distance_cm_s1 = 0.017 * duration_us_s1;
  distance_cm_s2 = 0.017 * duration_us_s2;

  if (distance_cm_s1 < 4.00) {
    Serial.print("Sensor1 distance: ");
    Serial.print(distance_cm_s1);
    Serial.print(" Result: ");
    Serial.println("Alert!");
    
  } else {
    // print the value to Serial Monitor
    Serial.print("Sensor1 distance: ");
    Serial.print(distance_cm_s1);
    Serial.println(" cm");
    

  }

  if (distance_cm_s2 < 4.00){
    Serial.print("Sensor2 distance: ");
    Serial.print(distance_cm_s2);
    Serial.print(" Result: ");
    Serial.println("Alert!");
  } else{
    Serial.print("Sensor2 distance: ");
    Serial.print(distance_cm_s2);
    Serial.println(" cm");

  }



  delay(500);
}