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. Not only are the trigger bus, 10 MHz system
reference clock, and star trigger bus available in PXI retained by PXI Express, but new timing
and synchronization features that include a 100 MHz differential system reference clock for
the synchronization of multiple modules and three differential star trigger buses for the
distribution of precise clock and trigger signals have been added. Differential timing and
synchronization signals provide PXI Express systems with increased noise immunity and the
ability to transmit clock signals at higher frequencies.
PXIe-8238 Overview
Functional Overview
The PXIe-8238 is a peripheral module that provides up to 10 Gigabit Ethernet (GbE)
connectivity on two SFP+ ports for a PXI Express system. It can attach to a PXI Express
system via a high-bandwidth, low-latency PXI Express backplane Gen2 x8 link.
With the 10Gb Ethernet, it allows offloading data from a PXI Express system to an external
storage solution or a server for further analysis. It also allows data exchange and aggregation
across two or more PXI Express systems.
Functional Description
The PXIe-8238 is a peripheral module in a 1-slot 3U PXI Express form factor. The following
figure is a functional block diagram of the PXIe-8238. Following the diagram is a description
of each logic block shown.
Figure 1. PXIe-8238 Block Diagram
PXI Express
PCI Express
Switch
NI ASIC
Ethernet
Controller
SFP+
Connector
SFP+
Connector
x8
x8
x1
OCP Mezzanine Card
The PXIe-8238 consists of the following logic blocks on two circuit card assemblies (CCA):
•
The
PXI Express Connectors
connect the PXIe-8238 to the PXI Express/CompactPCI
Express backplane.
•
The
PCI Express Switch
links the PXI Express backplane to the Ethernet controller on the
OCP mezzanine card with PCI Express x8 links.
•
The
OCP Mezzanine Card
block consists of the Ethernet controller and the SFP+
connectors that provide the 10 GbE connectivity.
PXIe-8238 User Manual
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© National Instruments
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