#include <LiquidCrystal.h>

LiquidCrystal lcd(12, 11, 10, 9, 8, 7);

uint8_t smile[8] = {
  0b00000,
  0b01010,
  0b00000,
  0b00100,
  0b00100,
  0b10001,
  0b01110,
  0b00000,
};

int count = 0;

const int MAX_SCREEN_WIDTH = 16;
const int FIRST_ROW = 0;
const int SECOND_ROW = 1;

void setup() {
  lcd.createChar(3, smile);
  lcd.begin(16, 2);
  lcd.setCursor(MAX_SCREEN_WIDTH, FIRST_ROW);
  lcd.print("Hello world! \x03");
}

void loop() {
  if (count == 40) {
    lcd.clear();
    lcd.setCursor(MAX_SCREEN_WIDTH, SECOND_ROW);
    lcd.print("Hello world! \x03");
  }
  if (count == 80) {
    lcd.clear();
    lcd.setCursor(MAX_SCREEN_WIDTH, FIRST_ROW);
    lcd.print("Hello world! \x03");
    count = 0;
  }

  lcd.scrollDisplayRight();
  count++;
  delay(100);
}