一种基于ARM9的多路差分信号采集系统

文章针对多路差分信号采集问题,提出了一种基于ARM9的高精度采集系统。该系统通过采用I/O模拟SPI接口工作时序的方法,把ADC纳入ARM9的存储管理;通过将差分信号转换为单端信号,简化了整个系统设计。通过比较采集软件实际接收数据值和从采集的SPI时序图读出的采样数据值,得出CPLD控制逻辑和采集软件设计符合要求以及单次采样误差小于2%。

Multi-channel Differential Signal Acquisition System Based on ARM9

To be aimed at the application of multi-channel differential signal acquisition, this paper proposed a new acquisition system based on ARM9 controller. The ADC module was brought into the orbit of memory management of ARM9 controller by the method of I/O simulating the timing sequence of SPI interface, The system design was simplified by converting differential signals to single-end ones. After comparing the actual received value with those gained from picked SPI sequence charts, the conclusion is obtained that the software works well and the single sampling error is less than 2 percents.