Design And Implementation Of Thermocouple Acquisition System Software Based On LXI

Temperature measurement is not only widely used in traditional industries such as industry,agriculture,mining,automobile and ship,but also has higher precision and more flexible use requirements in frontier disciplines such as aerospace technology,modern energy system,deep-sea and biomedicine.The thermocouple temperature measurement system studied in this thesis is a multichannel high-precision temperature measurement system based on LXI bus.The system has the network control mode of LXI instruments and supports distributed measurement,so it has the characteristics of flexible use and many sampling channels.Starting from the overall design of the thermocouple temperature measurement system,this thesis conducts a comprehensive analysis and design of the system software in combination with hardware functions and actual use scenarios.According to the data characteristics of the multi-channel thermocouple temperature measurement system,an appropriate data processing method is designed to improve the software Operational efficiency and measurement accuracy.The main research contents are as follows:（1）Software architecture design of high-precision multi-channel thermocouple temperature measurement system.In order to improve the decoupling degree of software and increase the scalability,the software is designed by the combination of layered architecture and event driven architecture;In addition,multithreading design is adopted for software parallel business to improve the operation efficiency of the system.（2）Upper computer software design.The remote human-computer interaction interface program is designed from the aspects of communication,discovery,control and display.The interface key response,parameter configuration,data processing and other functional modules are realized hierarchically and independently to improve the scalability of the system.（3）Arm program design.The LXI instrument discovery function is realized based on vxi-11 protocol,and the server program is built on the arm core board.A port mapping program for realizing RPC function is designed for embedded system.The clock synchronization function is realized based on PTP protocol;The design and analysis of instrument SPCI instruction are realized based on LXI protocol.Combined with hardware,the communication interface program based on GPMC bus and I2 C bus is improved;The number of I2C bus mounted devices and the communication mode of interface function are expanded,and the program compatibility is improved.（4）Design of temperature data processing module.Combined with the characteristics of the data collected by the instrument and the hardware functions,the calibration function is designed and implemented on the basis of the traditional thermocouple temperature data processing scheme and the idea of gradient descent.It improves the efficiency of data calibration while ensuring the accuracy of measurement data.The interpolation method of red-black tree is optimized according to the characteristics of data,which improves the efficiency of data storage and query.