基于DSP的双路频率-电压转换器的实现

在安卓手机控制外设的应用中,如果有效运用音频输出的频率信息,则可以拓展手机的控制方式。为此,按应用场合,需要测量输出音频信号的频率,并将其转换为模拟电压信号。介绍测周法测量数字信号频率的原理,给出测量误差与时基频率的关系,并详细论述系统软硬件平台的设计思路及实现方法,使用TMS320F28335型DSP处理器测量双路数字信号的频率,并以数模转换器DAC7724相应线性输出双路模拟电压信号,最后给出该系统的转换误差、转换时间与输出更新率。

Realization of 2 channels f-U converter based on DSP

In applications of Android phone controlling peripheral devices, the controlling method of phone can be extended if audio output frequency information is used effectively. Therefore, it is needed to measure frequency of output audio signal and convert it to analog voltage signal by application. This paper will introduce principle of measuring frequency of digital signal in cycle method, give the relationship between measuring error and base frequency, discuss design idea and realization method of system software and hardware platform in detail,measure the frequency of dual digital singals wih DSP （TMS320F28335）, linearly output dual analog voltage signal correspondingly with digital-to- analog convertor DAC7724,and give conversion error.coversion time and output update rate finaly.