这是单片机的一个非常好的一个资料，大家可以参考一下，单片机是个非常有用的入门级的，以后学ARM就非常简单了！学单片机最重要的就是看芯片资料-This is a very good single-chip data, we can refer to the microcontroller is a very useful entry-level, after school ARM is very simple! The most important thing is to learn microc