#include <LiquidCrystal_I2C.h>
#define I2C_ADDR    0x27
#define LCD_COLUMNS  20 // ou 20
#define LCD_LINES   4   // ou 4
LiquidCrystal_I2C lcd(I2C_ADDR, LCD_COLUMNS, LCD_LINES);

void setup() {
  lcd.init();
  lcd.backlight();
}

void loop() {
    lcd.setCursor(0, 0);
    unsigned long tempo = millis();
    lcd.print("Tempo(s): ");
    lcd.print((tempo/1000.),2);
    lcd.setCursor(0, 1);
     lcd.print("S1:");
     float v1 = analogRead(0)*5./1023;
     lcd.print(v1,1);
     lcd.print("V S2:");
     float v2 = analogRead(1)*5./1023;
     lcd.print(v2,1);
     lcd.print("V");
     
     lcd.setCursor(0, 2);
     lcd.print("S1:");
     lcd.print(v1,3);
     lcd.print("V S2:");
     lcd.print(v2,3);
     lcd.print("V");
     delay(10);  
}