#include <Wire.h>
#include <LiquidCrystal_I2C.h>

#define TRIG 2
#define ECHO 4
#define b1 16
#define b2 17


int contador = 0, litro = 0, t_p = 0;
long duration;
int distance;
bool s_e = 0, s_s = 0;


LiquidCrystal_I2C LCD(0x27, 16, 2);

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("by Gabriel Luz");
  LCD.init();
  LCD.backlight();
  LCD.setCursor(0,0);
  LCD.print("  Gabriel Luz  ");
  LCD.setCursor(0,1);
  LCD.print("TEC.MECATRONICA");
  delay(1000);
  LCD.clear();
  pinMode(TRIG, OUTPUT);
  pinMode(ECHO, INPUT);   
  pinMode(b1, OUTPUT);
  pinMode(b2, OUTPUT);
}

void loop() {
  digitalWrite(TRIG, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG, LOW);
  duration = pulseIn(ECHO, HIGH);
  contador = duration * 0.017;
  litro = map(contador, 3, 100, 10000, 0);
  LCD.setCursor(0, 0);
  LCD.print(litro);
  LCD.print(" L    ");
  delay(10);
  if(litro <= 1000){
    s_e = 1;
  }
  if(litro >= 10000){
    s_e = 0;
    digitalWrite(b2, LOW);
    digitalWrite(b1, LOW);
    LCD.setCursor(0, 1);
    LCD.print("b1=OFF    b2=OFF");
    s_s = !s_s;
  }
  if(s_e == 1 && s_s == 1){
    LCD.setCursor(0, 1);
    LCD.print("b1=ON     b2=OFF");
    digitalWrite(b1, HIGH);
    digitalWrite(b2, LOW);
  }
  if(s_e == 1 && s_s == 0){
    LCD.setCursor(0, 1);
    LCD.print("b1=OFF    b2=ON ");
    digitalWrite(b2, HIGH);
    digitalWrite(b1, LOW);

  }
}