Multi Platform Equipment Interchangeable Engine Research

With the rapid development of electronic measurement technique, the kinds of instruments for measuring are increasing day by day, but different manufacturers to develop similar instruments have different standards, it extends the instrument development cycle, and reduces the reuse of instrument UI. In order to reduce the development cycle and the cost for the upper UI of similar instrument, and easy to amend and maintain at the same time, the development standard of similar instruments by different manufactures needs unify, the interchangeable realization of device driver and hardware has great significance.The thesis references the IVI(Interchangeable Virtual Instrument) idea, the interchangeable engine module is formed through extracting the common attributes and functions of the same kind instruments. Meanwhile, the design and realization of interchangeable engine interfaces are analyzed in detail, the unified standard of developing the same kind instruments by different manufactures is formed finally. The main research contents are as follows:1.The design of the software uses the overall architecture layered design. The layered structure of developing instruments is given, functions and roles of upper UI,middle layer, device driver, hardware layer are analyzed. The structure of middle layer which is named interchangeable engine is provided in detail, this structure includes class driver and attribute engine modules. The idea of layered design is used to improve the independence among various modules and to reduce the coupling among various modules.2.The design and realization of interchangeable engine each module in detail.Class driver only finished the load and realization of device driver, the concrete operation for hardware is not referred, upper UI and device driver are separated.Attribute engine makes use of the feature which is keys corresponding of hash table to store attributes, the speed of looking up the attributes is improved; It makes uses of the dynamic storage feature of double-linked circular list to store the physical channel name and channel index of instrument, the convertible method between physical channel name and channel index is analyzed, the method of obtaining channel index is given;Combined with the principle of callback function, the callback function of different attributes are realized through the same function to operate attributes by using the3.callback mechanism. The range check of attributes is implemented through range check mechanism, the reliability of operating attribute is improved; The secure of data at the multi-thread running process is ensured by the thread synchronization method; Through method of the checkErr macro for handling error is to judge the value that return by function whether occurs abnormal, the security of running program is promoted.4.The design and implementation of cross-platform. Combined with the principle of conditional compilation, the compilation and application of different platform is distinguished through built-in macro_WIN32 on the Windows and built-in macro linux on the Linux, the load and destroy of dynamic link library on the different platform is analyzed, the realization of some functions for different platform are given. Finally,attribute engine library and class driver library are generated through the compiled environment tool chain on Windows and GCC command on Linux.According to the test result, for the same manufacturers to develop the same kind instruments, the interchangeable engine by this thesis ensures the interchange of device driver and hardware at the condition of maintaining UI program not be modified sharply.