每次按下 K1 时递增点亮一只 LED，全亮时再次按下则再次循环开始， K2 按下后点亮上面 4 只 LED，K3 按下后点亮下面 4 只 LED，K4 按下后关闭所有 LED -Each press K1 increments lit a LED full brightness when pressed again, the cycle begins again after 4 LED lit above press K2, K3 Press lit following four LE