#include <LiquidCrystal.h>

int screen = 0;

LiquidCrystal lcd(3, 4, 5, 6, 7, 8);

// You can put your own variables below this comment

void setup() {

lcd.begin(20, 4);

}

void loop() {

lcd.clear();

for(int i = 0; i < 255; i = i + 1) {
  lcd.write(i);
  delay(20);
}
delay(1000);
}