Instruments Interchangeability Using Interchangeable Virtual Instrument Technology

The ability to exchange the instruments in a test system without changing the test programs is an ongoing challenge in the test and measurement industry. Test systems that are used for years (10 plus) can incur large test program modifications and integration cost due to obsolete instruments or the need to upgrade an instrument to increase the test capability. The IVI Foundation has created specifications for programming test instruments that simplify interchangeability with the goal to reduce the cost of program development and maintenance. The IVI Foundation has defined classes for eight types of instruments at this time, so if IVI technology is going to be used as part of a test software architecture it needs to be expanded based on the requirements of a test system. In this paper, we present an approach for incorporating the use of interchangeable virtual instrument technology for the control and interchangeability of test instrumentation in a test software architecture solution. We identify the layers of the test software architecture and its use of components in the IVI shared components. The functionality of each component within the test software architecture is described, process for creating instruments and custom not defined by the IVI process will include steps and the tools that are used for designing and developing the classes and drivers, such as visual studio wizards that build templates to create new IVI class drivers and IVI instrument specific drivers. Finally, we demonstrate results of expanding the eight foundation IVI classes that were available when the project started into 37 IVI classes that support 54 instruments from multiple vendors.