【作者】 王娜；

【导师】 闵华松；

【作者基本信息】 武汉科技大学 ， 计算机应用技术， 2008， 硕士

【摘要】 随着嵌入式技术在虚拟仪器方面的应用逐渐增多,系统间协同工作也日益普遍,应用范围也更加广阔,涉及到多种语言、通信介质以及操作系统,软件开发往往要求在这些异构环境下运行。这时要实现协同工作,应用开发者不仅要关注具体的应用问题,还要花费大量精力了解底层特性,解决平台差异。为了解决嵌入式虚拟仪器应用中的异构性,加强协同工作能力,本文将“中间件”思想引入到嵌入式虚拟仪器中,设计了嵌入式虚拟仪器中间件模型。中间件作为一种采用组件思想设计的软件,具有实时性特性,符合嵌入式虚拟仪器对效率和资源的要求及限制。它主要为嵌入式虚拟仪器的开发提供跨语言、跨操作平台、模块化和可扩展的接口,借助中间件,只需改变适配层的相关参数,保持中间件层对应用层的接口定义不变,就可以直接将虚拟仪器应用程序移植运行,实现了应用程序“一次编写,多处运行”的思想,依靠中间件的兼容性增强嵌入式虚拟仪器系统的灵活性、适用性。本系统利用嵌入式GUI技术,结合组件化思想设计嵌入式虚拟仪器软面板;利用软硬结合的双缓冲技术消除页面闪烁,提高嵌入式软面板绘图速度以及逼真度;借鉴了IVI(可互换虚拟仪器)技术设计嵌入式虚拟仪器驱动器,并利用驱动引擎机制完成虚拟仪器的动态配置与调用;利用MinimumCORBA中间件规范设计本系统的用户接口,使其具有异构环境下的平台、语言无关性,满足工业现场或恶劣环境下的便携式虚拟仪器的设计需要,提高了嵌入式虚拟仪器的兼容性和可移植性,实现了大粒度的软件可重构。更多还原

【Abstract】 With the development of embedded technology and it is increasingly application to build VI, the requirements of cooperative work between different systems are also increased quickly, involving multiple hardware platforms, communications media, as well as operating systems. Developers are often required to run on in these heterogeneous hardware or software platforms. To achieve cooperative work, developers should not only focus on concrete applications, but also pay more attention to the bottom layer characteristic to solve the platform difference.How to improve the cooperation capability between heterogeneous environments and increase the reconfiguration of the system are the urgent problems we should solve in our presented embedded VI. For these goals, we are attempting to design an embedded VI based on middleware technology. Middleware as a component of software has the real-time characteristic and conforms to the efficiency and resource limit of embedded VI. Standing on the shoulders of the existing achievement made by many practitioners, we not only design a novel specification of the embedded VI, but also focus on the interface standard based on middleware technology. The core goal of the embedded VI middleware (EVIM) is the facilitate adaptation, provided by extensible, hierarchical and modularization middleware interfaces,improving portability and reconfiguration as well as ensuring high retractility, stability and easy-to-upgrade.This system uses the embedded GUI technology, unifies the modularization thought to design the embedded VI soft-panel. Using the double buffering technique to eliminate pages flicker and enhance soft-panel drawing speed and fidelity. Inspired by the standard of interchangeable virtual instruments (IVI), a set of standard class libraries and APIs are made and the configured dynamic calls of the VI are completed by using engine-driven. Based on the integrated analysis of the mainstream embedded middleware-MinimumCORBA, the user interface is designed in order to build a new embedded VI system in component-based mode with higher efficiency and code-reused rate.更多还原