PXI
Encyclopedia
- This is the article about electronic instrumentationElectronic instrumentationElectronic instrumentation refers to measuring instruments used to measure the properties of electrical devices.Electronics Instrumentation is a subject which deals with various types of electrical instruments with their functionality and operation....
platform, PXI. For the comic by Dan Kim, see Paper Eleven.
PCI eXtensions for Instrumentation (PXI) 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 industry-standard computer buses and permits flexibility in building equipment. Often modules are fitted with custom software to manage the system.
PXI Systems Alliance
PCIPeripheral Component Interconnect
Conventional PCI is a computer bus for attaching hardware devices in a computer...
eXtensions for Instrumentation (PXI) is a modular instrumentation platform originally introduced in 1997 by National Instruments
National Instruments
National Instruments Corporation, or NI , is an American company with over 5,000 employees and direct operations in 41 countries. Headquartered in Austin, Texas, it is a producer of automated test equipment and virtual instrumentation software...
. PXI is promoted by the 54-member PXI Systems Alliance (PXISA), whose sponsor members are (in alphabetical order) ADLINK
ADLINK
ADLINK Technology Inc. designs and manufactures products for embedded computing, test & measurement, and automation applications. ADLINK's product line includes computer-on-modules, industrial motherboards, data acquisition modules and complete systems...
, Aeroflex
Aeroflex
Aeroflex Inc. is an American company which produces and markets RF and microwave integrated circuits, components, and systems used for wireless communications. Aeroflex consists of Aeroflex Microelectronic Solutions , a fabless manufacturer of rad-hard and hi-rel semiconductor devices and...
, Agilent Technologies
Agilent Technologies
Agilent Technologies , or Agilent, is a company that designs and manufactures electronic and bio-analytical measurement instruments and equipment for measurement and evaluation...
, Geotest
Geotest
Geotest - Marvin Test Systems, Inc. is a producer of PXI and PC-Based test equipment, software and automated test solutions for the electronics industry. Geotest’s products and services include PXI chassis, controllers and instruments, Test Executive and development software , test systems and...
, Gigatronics, National Instruments
National Instruments
National Instruments Corporation, or NI , is an American company with over 5,000 employees and direct operations in 41 countries. Headquartered in Austin, Texas, it is a producer of automated test equipment and virtual instrumentation software...
, Pickering Interfaces
Pickering Interfaces
Pickering Interfaces is a test and measurement company headquartered in Clacton-on-Sea, UK. Pickering designs, manufactures and markets a range of programmable switching, instrumentation and cabling products in the LAN eXtensions for Instrumentation, PXI, IEEE-488, PCI and VXI platforms...
and Teradyne
Teradyne
Teradyne , a US company, is a supplier of automatic test equipment . The company's divisions Semiconductor Test and Systems Test Group, are organized by the products they develop and deliver.-History:...
. (Sep 2010)
Executive Members of the alliance include Alfautomazione, BAE Systems
BAE Systems
BAE Systems plc is a British multinational defence, security and aerospace company headquartered in London, United Kingdom, that has global interests, particularly in North America through its subsidiary BAE Systems Inc. BAE is among the world's largest military contractors; in 2009 it was the...
, CHROMA ATE Inc, GOEPEL electronic, LeCroy, MAC Panel, Virginia Panel Corp, and ZTEC Instruments. Another 40 associate member organizations that do not have voting rights are supporting PXI and use the PXI logo on their products and marketing material. (Sep 2010)
Two major players in 2006
In 2006 two major players, Agilent TechnologiesAgilent Technologies
Agilent Technologies , or Agilent, is a company that designs and manufactures electronic and bio-analytical measurement instruments and equipment for measurement and evaluation...
and Keithley Instruments
Keithley Instruments
Keithley Instruments is a measurement and instrument company headquartered in Solon, Ohio, that develops, manufactures, markets, and sells data acquisition products, as well as complete system solutions for high-volume production and assembly testing...
entered the PXI test market.
- Acqiris; was acquired by Agilent Nov 2006 .
- PXIT; an early PXI entrant (acquired by Agilent Nov 2006).
- Keithley InstrumentsKeithley InstrumentsKeithley Instruments is a measurement and instrument company headquartered in Solon, Ohio, that develops, manufactures, markets, and sells data acquisition products, as well as complete system solutions for high-volume production and assembly testing...
; launched a range of 35 Data Acquisition and Instrumentation PXI cards in Nov 2006.
Market estimate
The PXI worldwide market size, estimated in 2007, was and was expected to grow to over by 2010. The PXI market is also larger than the VME eXtensions for Instrumentation (VXI) market at an estimated size in 2007 of . . The LAN eXtensions for Instrumentation (LXI) standard has grown to within . .Overview
PXI is designed for measurement and automation applications that require high-performance and a rugged industrial form-factor. With PXI, one can select the modules from a number of vendors and integrate them into a single PXI system, over 1150 module types available in 2006. A typical 3URack unit
A rack unit or U is a unit of measure used to describe the height of equipment intended for mounting in a 19-inch rack or a 23-inch rack...
PXI module measures approximately (4x6") in size, and a typical 8-slot PXI chassis is 4U high and half rack width, full width chassis contain up to 18 PXI slots.
PXI uses PCI-based technology and an industry standard governed by the PXI Systems Alliance (PXISA) to ensure standards compliance and system interoperability. There are PXI modules available for almost every conceivable test, measurement, and automation application, from the ubiquitous switching modules and DMMs, to high-performance microwave vector signal generation and analysis. There are also companies specializing in writing software for PXI modules, as well as companies providing PXI hardware-software integration services.
PXI is based on CompactPCI
CompactPCI
A CompactPCI system is a 3U or 6U Eurocard-based industrial computer, where all boards are connected via a passive PCI backplane. The connector pin assignments are standardized by the PICMG US and PICMG Europe organizations. PICMG stands for PCI Industrial Computers Manufacturers Group...
, and it offers all of the benefits of the PCI
Peripheral Component Interconnect
Conventional PCI is a computer bus for attaching hardware devices in a computer...
architecture including performance, industry adoption, COTS
Commercial off-the-shelf
In the United States, Commercially available Off-The-Shelf is a Federal Acquisition Regulation term defining a nondevelopmental item of supply that is both commercial and sold in substantial quantities in the commercial marketplace, and that can be procured or utilized under government contract...
technology. PXI adds a rugged CompactPCI mechanical form-factor, an industry consortium that defines hardware, electrical, software, power and cooling requirements, leaving nothing to chance. Then PXI adds integrated timing and synchronization that is used to route synchronization clocks, and triggers internally. PXI is a future-proof technology, and is designed to be simply and quickly reprogrammed as test, measurement, and automation requirements change.
Most PXI instrument modules are register-based products, which use software drivers hosted on a PC to configure them as useful instruments, taking advantage of the increasing power of PCs to improve hardware access and simplify embedded software in the modules. The open architecture allows hardware to be reconfigured to provide new facilities and features that are difficult to emulate in comparable bench instruments. PXI system data bandwidth performance easily exceeds the performance of the older VXI test standard. There is debate within the technical community as to whether newer standards such as LXI will surpass PXI in both performance and overall cost of ownership.
PXI modules providing the instrument functions are plugged into a PXI chassis which may include its own controller running an industry standard operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
such as Windows XP
Windows XP
Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...
, Windows 2000
Windows 2000
Windows 2000 is a line of operating systems produced by Microsoft for use on personal computers, business desktops, laptops, and servers. Windows 2000 was released to manufacturing on 15 December 1999 and launched to retail on 17 February 2000. It is the successor to Windows NT 4.0, and is the...
, or Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
(which is not yet PXI System Alliance approved), or a PCI-to-PXI bridge that provides a high-speed link to a desktop PC controller. Likewise, multiple PXI racks can be linked together with PCI bridge cards, to build very large systems such as multiple source microwave signal generator test stands for complex ATE
Automatic test equipment
Automatic or Automated Test Equipment is any apparatus that performs tests on a device, known as the Device Under Test , using automation to quickly perform measurements and evaluate the test results...
applications.
CompactPCI
CompactPCI
A CompactPCI system is a 3U or 6U Eurocard-based industrial computer, where all boards are connected via a passive PCI backplane. The connector pin assignments are standardized by the PICMG US and PICMG Europe organizations. PICMG stands for PCI Industrial Computers Manufacturers Group...
and PXI products are interchangeable, i.e. they can be used in either CompactPCI or PXI chassis, but installation in the alternate chassis type may eliminate certain clocking and triggering features. So for example you could mount a CompactPCI Network interface controller in a PXI rack to provide additional network interface functions to a test stand. Conversely, a PXI module installed in a CompactPCI chassis would not utilize the additional clocking and triggering features of the PXI module.
PXI Express
The PXI Systems Alliance has passed specification PXI-5, which specifies how to integrate PCI ExpressPCI Express
PCI Express , officially abbreviated as PCIe, is a computer expansion card standard designed to replace the older PCI, PCI-X, and AGP bus standards...
performance into both CompactPCI and PXI while preserving backward compatibility
Backward compatibility
In the context of telecommunications and computing, a device or technology is said to be backward or downward compatible if it can work with input generated by an older device...
. Because PXI is based on CompactPCI, work began first on CompactPCI Express in early 2004. The CompactPCI Express specification defines the fundamental mechanical and electrical features of CompactPCI Express systems and, therefore, PXI Express systems. This includes the selection of connectors to support PCI Express, definitions of slots and board mechanicals, definitions of slot/board electrical signals, and compliance-testing requirements. The CompactPCI Express specification was released on June 27, 2005 and the PXI Express specification was completed in August 2005. PXI Express incorporates CompactPCI Express technology with enhancements for PXI compatibility, timing and synchronization, and system software frameworks.
The attached figure shows the basic layout of a CompactPCI/PXI Express backplane
Backplane
A backplane is a group of connectors connected in parallel with each other, so that each pin of each connector is linked to the same relative pin of all the other connectors forming a computer bus. It is used as a backbone to connect several printed circuit boards together to make up a complete...
and illustrates how PCI Express is integrated into backplanes while preserving compatibility with current PXI modules. PCI Express electrical lanes run from the system slot (either an embedded controller or MXI link) to the hybrid slots, providing a high-bandwidth path from the controller to the backplane slots. In addition, the installation of an inexpensive PCI Express-to-PCI bridge on backplanes provides PCI signaling to all PXI and PXI Express hybrid slots. This ensures compatibility with PXI modules on the backplane. The system controller slot is capable of supporting up to a x16 PCI Express link, plus a x8 link, providing a total of transfer capacity to the PXI backplane. This is a more than 45 times improvement in PXI backplane throughput.
A key new feature is the PXI Express hybrid slot, which delivers support for both PCI and PCI Express signaling by taking advantage of available pins on the high-density backplanes. This creates a level of backward compatibility not available in even desktop PC card-edge connectors. In this hybrid peripheral slot, you can install PXI modules that use PCI signaling, as well as future high-performance PXI Express modules, in the same slot. However PXI modules that have implemented the J2 backplane connector require minor factory modification by the instrument vendor to allow operation in the PXI Express hybrid slot (the majority of PXI cards implement J2).
PCI Express uses the same driver and OS model as PCI, which ensures complete software compatibility among PCI-based systems (such as PXI) and PCI Express-based systems (for example, PXI Express). Neither vendors nor customers need to revise driver software or application software for PCI Express-based systems. Therefore, in addition to providing hardware compatibility through the hybrid slot, PXI Express systems also help engineers preserve existing software investments.
MXI link
A MXI link consist of a PXI card and a PCI/CompactPCI card that provides a PC with direct control over the PXI backplane and connected cards. It's transparent to software. Throughout at maximum using fiber-optic or copper cabling. With fiber-optics the maximum length is .PXI Express patent
National Instruments PXI Express, ; http://www.patentstorm.us/patents/6981086.htmlFurther standards based on PXI
- In September 2009 the PXImc standard was launched http://www.tmworld.com/article/440758-PXI_expands_to_multiple_processors.php Which enables multiple processors.