The Interchangeable Virtual Instrument (IVI) is a standard for instrument drivers that aims to solve the problem of software incompatibility between similar instruments from different manufacturers. The IVI Foundation, a consortium of instrument manufacturers and users, defines the standard. The core benefit of IVI is interchangeability. Traditionally, if a test program was written to control a specific power supply model, and that model needed to be replaced with a similar one from a different vendor, the entire test program would have to be rewritten because the driver and command set would be different. IVI addresses this by defining a standardized Application Programming Interface (API) for specific classes of instruments, such as power supplies, digital multimeters, or oscilloscopes.
A programmer writes their code to this generic IVI class driver (e.g., the IviDCPwr class for DC power supplies) rather than to a specific instrument driver. This code might use functions like ConfigureOutput and Measure. The IVI architecture then uses a specific driver for the actual instrument connected to the system to translate these generic commands into the device's native language (e.g., SCPI). This means you can swap the physical power supply with another IVI-compliant model, change a single configuration setting in the software, and the original test program will run without any code modification. This greatly reduces software maintenance costs and increases the long-term viability of test systems.
IVI drivers come in two main flavors: IVI-C (for C/C++ and traditional languages) and IVI-COM (for use with environments like Visual Basic, C#, and LabVIEW).
Matsusada Precision supplies drivers for both IVI-C and IVI-COM.