/* Código para mostrar valor em dB */
const int Sensor1AI = 0; //Sensor Analogo Interno, Entrada A0
const int PinoDigital1 = 1; 

const int Sensor2AI = 2; //Sensor Analogo Externo, Entrada A1
const int PinoDigital2 = 3;

//int Estado = 0;
int ValorSensor1 = 0;
int valorMayor1 = 0;
float volt1 = 0;
int dB1 = 0;


int ValorSensor2 = 0;
int valorMayor2 = 0;
float volt2 = 0;
int dB2 = 0;

int cont = 0;
/* 
Board I2C / TWI pins
Uno       =   A4 (SDA), A5 (SCL)
 */
#include <Wire.h>
#include <LiquidCrystal_PCF8574.h>
LiquidCrystal_PCF8574 lcd(0x27); // set LCD address 0x27

void setup() {

  Serial.begin(9600);

  lcd.begin(16,2); // initialize 16x2 LCD
  lcd.setBacklight(255); // turn on backlight

  lcd.home(); // go home
  lcd.clear();
  
  lcd.setCursor(0, 0);
  lcd.print("Int:");
  lcd.setCursor(10, 0);
  lcd.print("dB");
  lcd.setCursor(0, 1);
  lcd.print("Ext:");
  lcd.setCursor(10, 1);
  lcd.print("dB");
}
void loop()
{
lcd.setCursor(6,0);
Serial.print(ValorSensor1);

lcd.setCursor(6,1);
Serial.print(ValorSensor2);

while(cont < 10000)
{
ValorSensor1 = analogRead(Sensor1AI);
if(ValorSensor1 > valorMayor1)
{
valorMayor1 = ValorSensor1;
}

ValorSensor2 = analogRead(Sensor2AI);
if(ValorSensor2 > valorMayor2)
{
valorMayor2 = ValorSensor2;
}
cont++;
}
cont = 0;
volt1 = valorMayor1/1023.0*4.53;
dB1 = 87.1*volt1 - 75,4;
if(dB1 < 0)
{
dB1 = 0;
}

volt2 = valorMayor2/1023.0*4.53;
dB2 = 87.1*volt2- 75,4;
if(dB2 < 0)
{
dB2 = 0;
}

lcd.print("");
lcd.setCursor(6,0);
lcd.print(dB1);

lcd.print("");
lcd.setCursor(6,1);
lcd.print(dB2);

valorMayor1 = 0;
valorMayor2 = 0;
delay(100);

}