说明：  此为一利用单片机编写的DDS程序，并且有液晶显示。其中的lcdhead.h中包含利用128*64的液晶显示的头文件，非常好用。
(this as a preparation using the DDS SCM procedures, and a liquid crystal display. The lcdhead.h included the use of 128* 64 LCD in the first document, very useful.)