【作者】 石磊；

【导师】 李兵兵； 金文仁；

【作者基本信息】 西安电子科技大学 ， 电子与通信工程， 2011， 硕士

【摘要】 随着材料科学的发展,X射线衍射仪越来越广泛地应用于人们的生产和科研领域,如冶金、材料、石油化工、航空航天和教学研究等。这些领域对材料成分的要求越来越高,而分析材料成分和结构的主要设备之一就是X射线衍射仪,所以对其精度和稳定性的要求也就越来越高。材料分析精度的提高,有利于更好的促进生产工艺和方法的改进,生产出更好的合格的材料。衍射仪控制系统需要完成多项任务。本系统主要功能是实现衍射仪的测角仪控制及X射线强度脉冲测量。根据要完成的功能,衍射仪控制系统由硬件和软件两部分组成。硬件包括上位机、控制板、高压电源板和LCD显示屏等,控制板为控制核心,与其他几部分均由RS232接口连接。控制板需要完成接收上位机发出的控制命令并实现对测角仪θ_θ方式控制、x射线强度脉冲计数、间接完成对高压电源板的控制等。本文给出了基于双ARM为控制单元,CPLD实现相关逻辑处理的硬件架构。主ARM主要完成对上位机命令分析和处理、X射线强度脉冲计数和实现LCD实时显示,从ARM接收主ARM的控制命令,实现对测角仪θ_θ方式电机同步控制,配合主ARM完成各种控制方式下的测量任务。经过深入的分析论证和大量的实验,验证了该方案的合理性和可行性。上述系统已完成安装调试和验收。测试结果表明,该系统满足设计要求,达到了预期的效果。更多还原

【Abstract】 More and more applications of X-ray diffractometers are presented in a lot of fields of production and scientific research with development of the society, including metallurgy, materials production, petrochemical industry, aerospace, science research and so on. The requirement for analysing material composition and structure is higher and higher, so are precision and stability for X-ray diffractometers which are one of main devices for it. Improvement for that would make productive technology and methods better, and produce better materials.Control system of X-ray diffractometers will realize a lot of tasks, the main functions are controling goniometer and counting pulses.Hardware contains PC,control board,high-voltage control system and LCD and so on.And control board is the key connecting other parts with RS232.Control board need to receive control instructions from PC,control goniometer with modeθ_θ,count pulses and control high-voltage board indectly.This paper adopts the hardware design of dual CPUs adding CPLD for related logical process based on the multitask of this system. This system with principal and subordinate CPUs being main controlling chip has completed analysis and pocessing PC instructions, the counting of X-ray pulses and LCD; and coprocessor receives control instruction,completes the modeθ_θcontrol of goniometer and motor control together with main CPU.Rationality and feasibility of this precept have been tested via refined analysis and plenty of experiments.The system has been installed, debugged and in used.The test result indicates that the system meets the requirements of the design and realizes all the expected function excellently.更多还原