Intelligent Measurement Based On MCU PIC16F877

Based on analyzing the development and tendency of microcontroller unit (MCU) and intelligent measurement, the intelligent measurement based on MCU PIC16F877 is designed, which is following the design principle梒onvenience, good practicability, high reliability and low cost.By this intelligent measurement, 4 ways analog signal and 4 ways switch signal (now international norm voltage and current signal 0-5mA, 4-20mA and 1-5V) can be acquired, transferred, displayed and give warning to defect. To input signal, smoothing is used in order to heightened the lever of confidence of input signal. To exceeding ultimate parameter signal, this device can warn and disply in order to announce on-the-spot operator to ensure productional safety. Using seriel communication mode though RS232C and RS485 interface , we can do near and far distance communicate with the upper microcomputer (PC) or MCU, whereby measured systym can be monitored on real-time.By means of the integrated development environment 桵PLAB-IDE software, assembling program and off-circuit simulation can be made. Together with using the in-circuit debugger, we can make the system realize the fuctions of in-circuit programming, in-circuit debugging, and downloading the assembling program, which makes the designingand developing of the device easier.Programming the communicaton interface by taking advantage of MSComm control component in Visual Basic 6. 0 can solve the problem of serial communication of the device with the upper personal computer, and the real-time data can be displayed.The result of testing every section of the system shows that the system can operate in good order, and meet a demand for designing.