Virtual instrument software architecture
Virtual Instrument Software Architecture, commonly known as VISA, is a widely used I/O API in the test and measurement (T&M) industry for communicating with instruments from a PC. VISA is an industry standard implemented by several T&M companies, such as, Anritsu, Bustec, Keysight Technologies, Kikusui, National Instruments, Rohde & Schwarz, and Tektronix.
The VISA standard[1] includes specifications for communication with resources (usually, but not always, instruments) over T&M-specific I/O interfaces such as GPIB and VXI. There are also some specifications for T&M-specific protocols over PC-standard I/O, such as HiSLIP[2] or VXI-11[3] (over TCP/IP) and USBTMC[4] (over USB).
The VISA library has standardized the presentation of its operations over several software reuse mechanisms, including through a C API exposed from Windows DLL, visa32.dll, over the Microsoft COM technology, and through a .NET API. Although there are several VISA vendors and implementations, applications written against VISA are (nominally) vendor-interchangeable thanks to the standardization of VISA's presentation and operations/capabilities. Implementations from specific vendors [specify] are also available for less common programming languages [specify] and software reuse technologies.
History
VISA was originally standardized through the VXIplug&play Alliance, a now-defunct T&M standards body. The current standard, "VISA Specification 5.0", is maintained by the IVI Foundation.
See also
- Standard Commands for Programmable Instruments (SCPI)
- High Speed LAN Instrument Protocol (HiSLIP)
- Instrument Driver
References
- ^ "VISA Specification". IVI Foundation.
- ^ "IVI-6.1: High-Speed LAN Instrument Protocol (HiSLIP)" (PDF). IVI Foundation.
- ^ "VXI-11 Bus Specification". VXI Bus Consortium.
- ^ "USB Test & Measurement Class Specification". USB Implementers Forum Inc.