In conventional DDS architecture, mapping from phase codes to amplitude codes is implemented through addressing ROM memory by phase codes. 在传统的直接频率合成器(DDS)中,相位到幅度的转化是通过相位码寻址只读存储器(ROM)来实现的。
According to demand of an applying system, this paper designs an extern circuit, which visits 96K memory by 16 addressing lines, and solves the problem of reuse of ROM/ RAM memory. 根据应用系统的要求,设计了用16根地址线寻扯96K内存的扩展电路,解决了ROM与RAM32K地址空间的复用问题。
The design of the traditional DDS is mainly based on look-up table to achieve, which put the output value corresponding to the phase store in ROM, and require the output waveform by addressing. 传统DDS的设计主要是基于查找表实现的,即将输出相位所对应的幅度值存储于ROM中,通过寻址的方式输出所需波形。