Test Connections

The PXI Express (PXI-5) standard was created by the PXI Systems Alliance to integrate PCI Express advances into the PXI standard to improve performance attainable in modular instrumentation and automation systems such as those utilized by automated test developers and technicians.  The PXI-Express standard brings with it several improvements but still provides a high degree of compatibility with the PXI-1 standard and compatibility with industry-standard software and operating systems.  For more information on the PXI-1 standard, please follow the link to this article: What is PXI?.

Instead of a shared parallel bus, PXI Express uses multiple point-to-point serial connections (“lanes”) for instrument communication.  Each lane consists of a pair of lines:  one transmitting and one receiving, each able to transfer data independently allowing unimpeded bidirectional communication.  A single-lane connection (‘x1’ or ‘by 1') has a bandwidth of 250 Mbytes/sec/direction.  The lanes are assigned to the instruments by a matrix switch and can routed to provide one or more instruments with additional bandwidth.  In this manner, devices with a higher bandwidth requirement can be allocated more resources.   The PXI Express standard also incorporates a 100 MHz differential system clock that is phase-aligned with the existing 10 MHz PXI system clock and can work in conjunction with the 33MHz PCI system clock.  Additional features include signaling to ensure that modules using system clocks or clock divisions are synchronized and point-to-point differential triggering.  A PXI Express controller utilizes the
PXI Express
same operating system and driver model as PXI.  This ensures that the test designer can reuse existing code and software with the newer PXI Express system.


A PXI Express chassis can have five slot types:
PXI Express System Slot: slot 1 shown above
PXI Express Peripheral Slot: slot 5 shown above
PXI Express System Timing Slot: slot 4 shown above
PXI Peripheral (PXI-1) Slot: slots 2 and 6 through 9 shown above
PXI Hybrid Slot: slot 3 shown above

To learn about the different slot types you can read the entire discussion on the PXI Express standard on the Geotest site.
(If the Print button is not supported, simply use your
Web browser's "Print" command instead.)

Geotest-Marvin Test Systems, Inc.
1770 Kettering
Irvine, CA 92614

Geotest - Marvin Test Systems, Inc.
©2011 Geotest-Marvin Test Systems, Inc. (www.geotestinc.com). All rights reserved.
Geotest - Marvin Test Systems, Inc. - Geat A Head Start With Geotest