基于模拟IIC总线的电压测量系统  

A design of voltage measurement system based on simulated IIC bus

作　　者：徐伟[1] 刘建成[1] 

机构地区：[1]南京信息工程大学电子与信息工程学院,南京210044

出　　处：《南京信息工程大学学报（自然科学版）》2011年第1期91-96,共6页Journal of Nanjing University of Information Science & Technology（Natural Science Edition）

基　　金：国家自然科学基金(61072133)

摘　　要：根据IIC总线的时序,编程模拟了IIC总线.基于模拟的IIC总线,采用8位串行接口A/D转换器PCF8591设计了电压测量系统.给出了系统硬件电路和主程序流程图.系统因采用IIC总线式结构而具有硬件结构简单、扩展性强的突出优点,为IIC总线在其他采集系统中的应用提供了参考.IIC bus is simulated by C51 program according to its time sequence.Based on this simulated IIC bus,a voltage measurement system is designed by the single chip microcomputer and 8-bit A/D and D/A converter PCF8591.The PCF8591 is a single-chip,single-supply low power 8-bit CMOS data acquisition device with four analog inputs,one analog output and a serial IIC bus interface.Three address pins A0,A1 and A2 are used for programming the hardware address,allowing the use of up to eight devices connected to the IIC bus without additional hardware.Address,control and data to and from the device are transferred serially via the two-line bidirectional IIC bus.The functions of the PCF8591 include analog input multiplexing,on-chip track and hold function,8-bit analog-to-digital conversion and an 8-bit digital-to-analog conversion.The maximum conversion rate is given by the maximum speed of the IIC bus.The circuit and main program flow chart are proposed in this paper.The system has simple structure and strong expandability owes to the IIC bus.It provides reference for the application of IIC bus in acquisition system.

关 键 词：IIC总线 电压测量 PCF8591 

分 类 号：TP274[自动化与计算机技术—检测技术与自动化装置]