Design of Hydrologic Measuring System Based on MSP430F149
|School||Taiyuan University of Technology|
|Keywords||Pressure Transducer Upper machine Lower machine MSP430F149 Visual basic6.0|
Ordovician water inrush is the main source of coal mine accidents which bring to life harm of the staff who work underground, so it is very important to monitor Ordovician water. Intelligent pressure transmitter is the core of hydrological monitoring system of coal mine. Data acquisition of Ordovician limestone water and ash water is completed by PT403and is transmitted to user computer through RS-485by intelligent pressure transmitter. We can monitor the Ordovician water pressure through the upper machine.The paper describes in detail the design of hydrological monitor system. Coal mine monitor system includes two parts:upper machine and lower machine. The monitoring interface of upper machine is designed based on visual basic6.0.it can communicate with the lower machine through Serial to Ethernet NP5130module. Then we can monitor the pressure of Ordovician water through upper machine easily. Ordovician water pressure is detected by PT403senor.PT403senor convert the pressure signal into voltage signal. The MCU(MSP430F149) convert the voltage signal into digital signal, then transmit digital signal to the upper machine. The monitoring interface of upper machine is designed based on visual basic6.0. visual basic6.0not only inherits the its ancestors feature, simple and easy to use, but also the programming system uses object-oriented mechanisms. VB6.0provides a design method of visual interface. VB6.0contains abundant controls, such as winsocket controls and it can call API function which inside of the package of windows system. upper machine is not only monitor the variation of pressure of Ordovician water but also send messages to the supervisors who can make decision once pressure of Ordovician water is higher than the normal level.MSP430F149microchip is the core of lower machine.MSP430F149microchip integrated12-channel A/D converter.MSP430F149MCU have following characteristics:6bit RISC, Five low power saving mode. PT430pressure senior with a inner thermistor for temperature compensation, could convert the pressure signal into voltage signal. After the voltage signal being amplified, MSP430F149begin to acquire the signal. Software programming into MSP430F149mainly implement hardware functionality. Such as ADC data acquisition program, Serial communication program, LCD display, DS18B20temperature acquisition program.Silicon piezo-resistive sensor is influenced by semiconductor materials; the temperature affects the output characteristics. Output characteristic manifest-tations are usually in the form of zero-degree temperature drift and temperature sensitivity adjustment. So, this paper adapts digital filter algorithms to overcome the system’s random errors and fluctuations due to factors or sample-and-hold caused by unstable pulse interference. This article adapts continuous function fitting method of minimizing system errors and improving the accuracy of intelligent transmitter.