基于嵌入式ARM7和μClinux的PSD称重系统研究

Research of PSD weighting system based on ARM7 and μClinux

基于嵌入式ARM7(S3C44B0)和μClinux操作系统设计了一个秤重设备。该设备应用了位置敏感探测器(Posi-tion Sensitive Detector,简称PSD),即将重量信号转换成PSD的电流信号,再将PSD电流信号转换为ARM7微处理器可以采集到的电压信号,经过整流和滤波电路,最后进入A/D转换器。在得到A/D输出的数字量后,根据其与物体重量存在的关系可得物体的重量。经试验验证,设计的秤重设备具有灵敏度高,速度快,精度佳,测量范围大,成本低的特点。

Based on ARM7（S3C44B0） and μClinux operating system, a weighting system is designed in this paper.This system uses position sensitive detector（PSD）.First,it can change an weighting signal into current signal of the PSD, then change the current signal into a voltage signal which the ARM7 microprocessor gather.Through undergo rectification and filter circuit,Finally this signal enters to MD converter.According to the relation of the digital signal and the weight of the object,we can get the weight of the object.Experimental results showed that the weighting system is high sensitivity, high speed, high precision, wide measure range and low cost.