本次设计用单片机芯片AT89s52设计一个数字万用表，能够测量交、直流电压值、直流电流、直流电阻以及电容，四位数码显示。此系统由分流电阻、分压电阻、基准电阻、电容测试芯片电路、51单片机最小系统、显示部分、报警部分、AD转换和控制部分组成。-The design used to design a single chip AT89s52 digital multimeter can measure AC and DC voltage, DC current, DC resistance and capacitance, four digital display. This system consists of shunt resistors, voltage divider, reference resistors, capacitors, circuit test chip, the smallest single-chip system 51, display parts, alarm some, AD converter and control components.