Instrument control consists of connecting a desktop instrument to a computer and taking measurements.

History

In the late 1960s the first bus used for communication was developed by Hewlett-Packard 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 Electronics 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. The standard was updated in 1987 and again in 1992 This bus is known by three different names, General Purpose Interface Bus (

GPIB Glycoprotein Ib (GPIb), also known as CD42, is a component of the GPIb-V-IX complex on platelets. The GPIb-V-IX complex binds von Willebrand factor, allowing platelet adhesion and platelet plug formation at sites of vascular injury. It is defici ...

), Hewlett-Packard Interface Bus (HP-IB), and

IEEE-488 IEEE 488 is a short-range digital communications 8-bit parallel multi-master interface bus specification developed by Hewlett-Packard as HP-IB (Hewlett-Packard Interface Bus). It subsequently became the subject of several standards, and is ...

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 () is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in 1 ...

USB Universal Serial Bus (USB) is an industry standard that establishes specifications for cables, connectors and protocols for connection, communication and power supply (interfacing) between computers, peripherals and other computers. A broad ...

, Serial, PCI, and PXI.

Software

In addition to the hardware bus to control an instrument, software for the PC is also needed.

Virtual Instrument Software Architecture Virtual instrument software architecture (VISA) is a widely used application programming interface (API) in the test and measurement (T&M) industry for communicating with instruments from a computer. VISA is an industry standard implemented by sev ...

, or VISA, was developed by the VME eXtensions for Instrumentation (VXI)

plug and play In computing, a plug and play (PnP) device or computer bus is one with a specification that facilitates the recognition of a hardware component in a system without the need for physical device configuration or user intervention in resolving resou ...

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 A programming language is a system of notation for writing computer programs. Most programming languages are text-based formal languages, but they may also be graphical. They are a kind of computer language. The description of a programming ...

s and defined in-depth specifications to guarantee interoperability of components within each framework. Instruments can be programmed by sending and receiving text based SCPI commands or by using an instrument driver . To ease the programming of instruments, many instruments are provided with industry standard instrument drivers such as VXIplug&play or IVI. These drivers require a VISA library to be to installed on the PC. IVI instrument drivers were designed to enable interchangeability of instruments in a manufacturing setting where automation and reduced down-time are important, but they are often used in other applications as well. Application development environments can support instrument control by supporting VISA and industry standard instrument drivers. Environments supporting VISA include

LabVIEW Laboratory Virtual Instrument Engineering Workbench (LabVIEW) is a system-design platform and development environment for a visual programming language from National Instruments. The graphical language is named "G"; not to be confused with G-c ...

, LabWindows/CVI,

MATLAB MATLAB (an abbreviation of "MATrix LABoratory") is a proprietary multi-paradigm programming language and numeric computing environment developed by MathWorks. MATLAB allows matrix manipulations, plotting of functions and data, implementa ...

, and VEE. Furthermore, the VISA library can support programming languages like C,

C++ C++ (pronounced "C plus plus") is a high-level general-purpose programming language created by Danish computer scientist Bjarne Stroustrup as an extension of the C programming language, or "C with Classes". The language has expanded significan ...

, C#,

Python Python may refer to: Snakes * Pythonidae, a family of nonvenomous snakes found in Africa, Asia, and Australia ** ''Python'' (genus), a genus of Pythonidae found in Africa and Asia * Python (mythology), a mythical serpent Computing * Python (pro ...

and others.

References

External links

Instrument Control Fundamentals
Presents technical content through theory, real-world examples, and interactive audiovisual tutorials - From National Instruments
VXIplug&play

IVI Foundation

Development Hints and Best Practices for Using Instrument Drivers - From Rohde & Schwarz

History

Software

See also

References

External links

Further reading