Powering Off The Mxi-Express X1 System; Led Indicators - National Instruments PCI-8361 User Manual

3. Observe the LED status on the PCI-8361, PCIe-8361/8362/8363,
PXI-8360/8364/8367/8368, and PXIe-8360/8364/8367/8368 where applicable. A properly
connected and powered up system should display a valid link and power status on all of
these boards once the host PC is powered on. Refer to the
information.
Typical PCI-PCI bridges are used to add PCI devices to a PCI hierarchy in which all the bridges
and devices are contained within a single chassis. Because of this, BIOSes and operating systems
make the assumption that all PCI devices in the entire hierarchy will be available as soon as code
execution begins at power-up time. This assumption means that all of the expansion chassis must
be turned on before the host PC for the BIOS and OS to correctly configure a MXI-Express
system.
In some cases where there is an invalid MXI-Express x1 connection, some
Note
boards may report a valid link while others do not. It is important to observe a valid
link status across all connected MXI-Express x1 boards when the host is powered on
to ensure a valid configuration.

Powering Off the MXI-Express x1 System

Because operating systems and drivers commonly make the assumption that PCI devices will be
present in the system from power-up to power-down, it is important not to power off the
expansion chassis until after the host PC is powered off. Powering off the expansion chassis
while the host is still on can cause crashes or hangs. However, once the host PC is powered off,
the order that the expansion chassis are powered off is not important.

LED Indicators

The LEDs on MXI-Express x1 cards provide status information about power supplies and link
state. The PCI-8361, PXI-8364/8367, and PXIe-8364 all have one tri-color LED on the panel,
indicating power and link status. The PCIe-8362 has two tri-color LEDs on the panel, indicating
power and link status for each port. The PXI-8360/8368 and PXIe-8360 have two LEDs, one for
power supply status and one for link state.
In some cases where there is an invalid MXI-Express x1 connection, some
Note
boards may report a valid link while others do not. It is important to observe a valid
link status across all connected MXI-Express x1 boards when the host is powered on
to ensure a valid configuration.
MXI-Express x1 Series User Manual
LED Indicators
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