index.lua

Screen.waitVblankStart()
Screen.refresh()

Screen.debugPrint(5, 5, "Hello world!", Color.new(255, 255, 255), TOP_SCREEN)
Screen.debugPrint(5, 5, "Here's a random number: "..math.random(1, 100), Color.new(255, 0, 0), BOTTOM_SCREEN)

Screen.flip()

while true do
  if Controls.check(Controls.read(), KEY_B) then
    System.exit()
  end
end