National Instruments NI PXIe-8105 Introduction

Introduction

This chapter provides overview information for PXI Express and the

NI PXIe-8105 embedded controller.

The PXI (PCI eXtensions for Instrumentation) industry standard, an open

specification governed by the PXI Systems Alliance (PXISA), has quickly

gained adoption and grown in prevalence in test, measurement, and control

systems since its release in 1998. One of the key elements driving the rapid

adoption of PXI is its use of PCI in the communication backplane. As the

commercial PC industry has improved the available bus bandwidth by

evolving PCI to PCI Express, PXI is now able to meet even more

application needs by integrating PCI Express into the PXI standard. By

taking advantage of PCI Express technology in the backplane, PXI Express

increases the available PXI bandwidth from up to 132 MB /s t o up to 6 GB/ s

for a more than 45x improvement in bandwidth.

PXI Express maximizes both hardware and software compatibility with

PXI modules. PXI Express hybrid slots deliver both PCI and PCI Express

signaling to accept devices that use PXI communication and triggering or

the newer PXI Express standard. Software compatibility is maintained

because PCI Express uses the same OS and driver model as PCI, resulting

in complete software compatibility among PCI-based systems, for example

PXI, and PCI Express-based systems such as PXI Express.

PXI Express, like PXI, leverages from the CompactPCI specification to

define a rugged, modular form factor that offers superior mechanical

integrity and easy installation and removal of hardware components.

PXI Express products offer higher and more carefully defined levels of

environmental performance required by the shock, vibration, temperature,

and humidity extremes of industrial environments. Mandatory

environmental testing and active cooling is added to the CompactPCI

mechanical specification to ease system integration and ensure multivendor

interoperability.

The demanding timing and synchronization requirements of

instrumentation systems are met by the integrated features of PXI Express.