Chapter 2
Hardware Installation
©
National Instruments Corporation
2-5
MXI-Express x16 for PXI Express Series User Manual
Powering On the MXI-Express x16 System
Follow these steps to power on the MXI-Express x16 system.
1.
Power on all expansion chassis in any order you choose.
2.
Power on the host.
Standard PCI-PCI bridges and switches 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 are available as soon
as code execution begins at power on. This assumption means that all
expansion chassis must be powered on before the host PC for the BIOS and
OS to correctly configure a MXI-Express x16 system.
Note
There are no requirements on how MXI-Express x16 expansion chassis are powered
on relative to each other, as long as they are all on before the computer is powered on.
Powering Off the MXI-Express x16 System
Because operating systems and drivers commonly make the assumption
that PCI devices are present in the system from power on to power off, 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 still is on
can cause crashes or hangs.
After the host computer has powered off, the order in which expansion
chassis are powered off relative to each other is not important. However, to
power off a chassis that still has its upstream link active, you must press the
power button for at least 4 seconds.
