说明：  使用LabVIEW实现了DDS芯片AD9833的编程助手的功能，输入晶振频率和想要的输出频率即可得到控制字。很方便编程。
(Using LabVIEW to implement the function of the DDS chip AD9833 s programming assistant, you can get the control word by typing the oscillator frequency and the desired output frequency. It s easy to program. )