说明：  一个不错的ARM入门建议,51是一个基础，而且还很重要，这是再我看了ARM之后感觉到的。它可以加速你的ARM学习速度，真得！不相信你试一试好了
(A good entry-ARM suggested that 51 is a basis, and very important, it is no longer felt after I read the ARM. It can speed up your learning speed ARM, really! Do not believe that you try it)