Research On Electronic Measurement Station Software Integration Techniques Base On Virtual Instrument Architecture

Virtual Instrument (VI) is a landmark in the development of testing field, it promotes greatly the research and application of the Electronic Measurement technology. VI brings forward the new concept of "Software is the Instrument". In a VI system, software is the core of the testing system, it separates the key platform of the software system and the concrete functional modules, the two inter-associate each other with the contracted software interfaces. The function of the instrument can be defined and designed by the user, then to change and enhance the function and size of the instrument system to meet all kinds of specific requirements. The development of the VI technology makes the construction of multi-module integrated testing device possible, and the complexity of the objects under test makes the research of multi-function integrated testing device that can perform multi-parameter testing task necessary. This dissertation addresses key techniques of the multi-module VI software integration domain. The research focuses on multi-module VI software architecture, driver, synchronization, cooperation and multi-module user interface techniques. The impressive contributions are as follows.1. The thesis Extents the VI software integration from single module work mode to multi-module cooperation work mode. A top layer integration architecture of the multi-module cooperation is presented, it simplified the management between the top layer and the modules to the call of the module interface. The top layer integration architecture seperates the two layers, and makes the increase/decrease and upgrade of modules more convenient, it meets the requirements of openness and extensibility. The user interface configuration and management is based on the XML technique and can realizes the dynamic configureation. It can automatically implement deployment and display of the user interface, and can conveniently transfer between multi-module and single module user interfaces.2. A command interface is presented base on the command queue. It uses command queue as the buffer of the commands that the upper function module layer send to control the device, the command parser parses the commands taken from the queue and transfers the commands to the command dispatcher, there the lower driver will be called. The command interface simplified the interface between the upper layer and lower driver, and it also separates the two layers. It transfers the mutually exclusive and competitive share mode of the device to the ordinal share mode, it also enhances the exchangeability of the upper modules.3. A data interface is presented based on the data queue. While a round of sampling is over, the data interface reads all modules'data from the device and store to the data queue. The data dispatcher first gets the measure data and parts the data according to the modules, and then dispatches the data to the modules, thus ends a round of test. The use of data queue to store, part and dispatch the sampling data, ensures the multi-module's synchronization based on the instruments'function.4. A driver abstract interface layer is presented based on the command interface and the data interface. The driver interface layer abstracts and encapsulates the instruments'driver. It uses command interface as the device manipulation mechanism, and data interface as the data notification mechanism, between the upper modules and lower driver layer. The driver interface layer improves the query and waiting mechanism to the queue and notification mechanism. Experimental results are given, showing that the queue and notification mechanism solves the competition for the bus and the device, and it increases the efficiency of the instruments driver compares to the query and wait mechanism.