1、　　利用FLEX10的片内RAM资源，根据DDS原理，设计产生正弦信号的各功能模块和顶层原理图； 2、　　利用实验板上的TLC7259转换器，将1中得到的正弦信号，通过D/A转换，通过ME5534滤波后在示波器上观察； 3、　　输出波形要求： 在输入时钟频率为16KHz时，输出正弦波分辨率达到1Hz； 在输入时钟频率为4MHz时，输出正弦波分辨率达到256Hz； 4、　　通过RS232C通信，实现FPGA和PC机之间串行通信，从而实现用PC机改变频率控制字，实现对输出正弦波频率的控制。-a use FLEX10-chip RAM resources, in accordance with DDS principle, design sinusoidal signal generated by the top-level functional modules and schematics; 2, the experimental board TLC7259 converters, will be a sinusoidal signal, the D / A conversion, after filtering through the ME5534 oscilloscope observation; 3, the output waveform requirements : the input clock frequency of 16KHz, sine wave output resolution of 1Hz; the input clock frequency of 4MHz, the sine wave output resolution of 256Hz; 4, RS232C communications, FPGA and PC serial communications between in order to achieve PC-frequency control characters, the realization of sine wave output frequency control.