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Chapter 3
Hardware Overview
©
National Instruments Corporation
3-3
Fiber-Optic MXI-Express x4 for PXI Express User Manual
Cabled Fiber-Optic MXI-Express x4 Connector
The cabled Fiber-Optic MXI-Express x4 connector provides the transmit
and receive signals to connect an NI PCIe-8375 and an NI PXIe-8375.
PCI Express-to-PCI Bridge
The PCI Express Base Specification defines a PCI Express-to-PCI bridge
as a device that connects a PCI Express fabric and a PCI hierarchy. On the
NI PXIe-8375, the PCI Express-to-PCI bridge connects the PCI Express
switch and an SMBus Master on the card.
SMBus Master
The SMBus is a low-speed bus for reading and configuring devices outside
the normal PCI Express mechanism. The PXI Express specification
requires controllers to supply an SMBus for reading chassis configuration
information from an EPROM. It may also be used for fan control, power
monitors, or other system devices. In addition, devices on plug-in boards
may connect to the SMBus for purposes specific to those devices.
LED Indicators
The LEDs on Fiber-Optic MXI-Express x4 cards give status information
about power supplies and link state. The NI PCIe-8375 has one tri-color
LED for the port on the panel. The NI PXIe-8375 has two tri-color LEDs,
one for each port.
The front-panel LEDs on the NI PCIe-8375 and NI PXIe-8375 indicate the
following:
Table 3-1.
NI PCIe-8375 and NI PXIe-8375 Status LED Messages
LED
Meaning
Off
Power is off
Red, Blinking
Power is out of spec
Amber
Power is within spec; link not established
Green
Power is within spec; link established