Instrument control
Encyclopedia
Instrument control consists of connecting a desktop instrument to a computer and taking measurements.
and was called HP-IB (Hewlett-Packard Interface Bus). Since HP-IB was originally designed to only work with HP instruments, the need arose for a standard, high-speed interface for communication between instruments and controllers from a variety of vendors. This need was addressed in 1975 by the Institute of Electrical and Electronic Engineers (IEEE) published ANSI/IEEE Standard 488-1975, IEEE Standard Digital Interface for Programmable Instrumentation, which contained the electrical, mechanical, and functional specifications of an interfacing system. This bus is known by three different names, General Purpose Interface Bus (GPIB), Hewlett-Packard Interface Bus (HP-IB), and IEEE-488
Bus, and is used worldwide.
Today, there are several other buses in addition to the GPIB that can be used for instrument control. These include: Ethernet
, USB, Serial
, PCI
, and PXI
.
is also needed. Virtual Instrument Software Architecture
, or VISA, was developed by the VME eXtensions for Instrumentation (VXI) plug and play Systems Alliance as a specification for I/O software. VISA was a step toward industry-wide software compatibility. The VISA specification defines a software standard for VXI, and for GPIB, serial, Ethernet and other interfaces. More than 35 of the largest instrumentation companies in the industry endorse VISA as the standard. The alliance created distinct frameworks by grouping the most popular operating systems, application development environments, and programming language
s and defined in-depth specifications to guarantee interoperability of components within each framework.
Application development environments can support instrument control by supporting VISA. Environments supporting VISA include LabVIEW
, LabWindows/CVI
, MATLAB
, and VEE
. Furthermore the VISA library can support programming languages like C
, C++
, C# and others.
History
In the late 1960s the first bus used for communication was developed by Hewlett-PackardHewlett-Packard
Hewlett-Packard Company or HP is an American multinational information technology corporation headquartered in Palo Alto, California, USA that provides products, technologies, softwares, solutions and services to consumers, small- and medium-sized businesses and large enterprises, including...
and was called HP-IB (Hewlett-Packard Interface Bus). Since HP-IB was originally designed to only work with HP instruments, the need arose for a standard, high-speed interface for communication between instruments and controllers from a variety of vendors. This need was addressed in 1975 by the Institute of Electrical and Electronic Engineers (IEEE) published ANSI/IEEE Standard 488-1975, IEEE Standard Digital Interface for Programmable Instrumentation, which contained the electrical, mechanical, and functional specifications of an interfacing system. This bus is known by three different names, General Purpose Interface Bus (GPIB), Hewlett-Packard Interface Bus (HP-IB), and IEEE-488
IEEE-488
IEEE-488 is a short-range digital communications bus specification. It was created for use with automated test equipment in the late 1960s, and is still in use for that purpose. IEEE-488 was created as HP-IB , and is commonly called GPIB...
Bus, and is used worldwide.
Today, there are several other buses in addition to the GPIB that can be used for instrument control. These include: Ethernet
Ethernet
Ethernet is a family of computer networking technologies for local area networks commercially introduced in 1980. Standardized in IEEE 802.3, Ethernet has largely replaced competing wired LAN technologies....
, USB, Serial
Serial communications
In telecommunication and computer science, serial communication is the process of sending data one bit at a time, sequentially, over a communication channel or computer bus. This is in contrast to parallel communication, where several bits are sent as a whole, on a link with several parallel channels...
, PCI
Peripheral Component Interconnect
Conventional PCI is a computer bus for attaching hardware devices in a computer...
, and PXI
PXI
PCI eXtensions for Instrumentation is one of several modular electronic instrumentation platforms in current use. These platforms are used as a basis for building electronic test equipment, automation systems, modular laboratory instruments in science, and the like. PXI is based on...
.
Software
In addition to the hardware bus to control an instrument, software for the PCPersonal computer
A personal computer is any general-purpose computer whose size, capabilities, and original sales price make it useful for individuals, and which is intended to be operated directly by an end-user with no intervening computer operator...
is also needed. Virtual Instrument Software Architecture
Virtual Instrument Software Architecture
Virtual Instrument Software Architecture, commonly known as VISA, is a widely used I/O API in the test and measurement industry for communicating with instruments from a PC...
, or VISA, was developed by the VME eXtensions for Instrumentation (VXI) plug and play Systems Alliance as a specification for I/O software. VISA was a step toward industry-wide software compatibility. The VISA specification defines a software standard for VXI, and for GPIB, serial, Ethernet and other interfaces. More than 35 of the largest instrumentation companies in the industry endorse VISA as the standard. The alliance created distinct frameworks by grouping the most popular operating systems, application development environments, and programming language
Programming language
A programming language is an artificial language designed to communicate instructions to a machine, particularly a computer. Programming languages can be used to create programs that control the behavior of a machine and/or to express algorithms precisely....
s and defined in-depth specifications to guarantee interoperability of components within each framework.
Application development environments can support instrument control by supporting VISA. Environments supporting VISA include LabVIEW
LabVIEW
LabVIEW is a system design platform and development environment for a visual programming language from National Instruments. LabVIEW provides engineers and scientists with the tools needed to create and deploy measurement and control systems.The graphical language is named "G"...
, LabWindows/CVI
LabWindows/CVI
LabWindows/CVI is an event-driven, ANSI C programming environment developed by National Instruments. The program was originally released as LabWindows for DOS in 1987, but was soon reinvisioned for the Microsoft Windows platform...
, MATLAB
MATLAB
MATLAB is a numerical computing environment and fourth-generation programming language. Developed by MathWorks, MATLAB allows matrix manipulations, plotting of functions and data, implementation of algorithms, creation of user interfaces, and interfacing with programs written in other languages,...
, and VEE
VEE
VEE or Vee may refer to:* "Vee", common English pronunciation of V, the twenty-second letter in the Latin alphabet* VEE, Venezuelan Equine Encephalomyelitis virus, a mosquito-borne viral horse pathogen...
. Furthermore the VISA library can support programming languages like C
C (programming language)
C is a general-purpose computer programming language developed between 1969 and 1973 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system....
, C++
C++
C++ is a statically typed, free-form, multi-paradigm, compiled, general-purpose programming language. It is regarded as an intermediate-level language, as it comprises a combination of both high-level and low-level language features. It was developed by Bjarne Stroustrup starting in 1979 at Bell...
, C# and others.
See also
- Instrument DriverInstrument DriverAn Instrument Driver, in the context of Test & Measurement application development, is a set of software routines, which simplifies remote instrument control. The specification of instrument drivers is defined by the IVI Foundation....
- AutomationAutomationAutomation is the use of control systems and information technologies to reduce the need for human work in the production of goods and services. In the scope of industrialization, automation is a step beyond mechanization...
- IEEE-488IEEE-488IEEE-488 is a short-range digital communications bus specification. It was created for use with automated test equipment in the late 1960s, and is still in use for that purpose. IEEE-488 was created as HP-IB , and is commonly called GPIB...
- Standard Commands for Programmable Instruments
- Virtual Instrument Software ArchitectureVirtual Instrument Software ArchitectureVirtual Instrument Software Architecture, commonly known as VISA, is a widely used I/O API in the test and measurement industry for communicating with instruments from a PC...
(VISA) - LabVIEWLabVIEWLabVIEW is a system design platform and development environment for a visual programming language from National Instruments. LabVIEW provides engineers and scientists with the tools needed to create and deploy measurement and control systems.The graphical language is named "G"...
- LabWindows
- Agilent VEEAgilent VEEAgilent VEE is a graphical dataflow programming software development environment from Agilent Technologies for automated test, measurement, data analysis and reporting. VEE originally stood for Visual Engineering Environment and developed by HP designated as HP VEE; it has since been officially...
- LAN eXtensions for Instrumentation
External links
- Instrument Control Fundamentals Presents technical content through theory, real-world examples, and interactive audiovisual tutorials - From National Instruments
- VXIplug&play
- GPIB Tutorial
- IVI Foundation
- Development Hints and Best Practices for Using Instrument Drivers - From Rohde & Schwarz