OK! Execute the following tested codes. the Hello! should appear on the Top Line of your LCD.
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x3F, 16, 2);
void setup()
{
lcd.init();
lcd.backlight();
lcd.setCursor(0, 0); //DP0 of Top Line
lcd.print("Hello!");
}
void loop()
{
}