6. Chassis and host controller power up or down sequence
This section describes the chassis and host controller PC power up and power down sequences. In order for the chassis and the host controller PC to interoperate correctly, they must be powered up and down in specific sequences.
Furthermore, the PC must be restarted in certain situations after the chassis and
PC are powered up. If these sequences are not followed, the PC may not be able to access the chassis or the modules in the chassis.
The chassis has three power states: Powered up, powered down, and unplugged. When powered up, the chassis is fully operational. When powered down, the Primary Power Module
(described in Power supply operation on page 1
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) is turned off,
but 5 Vaux is available to the Monitor Processor and the modules. When unplugged, the chassis is completely unpowered. Unless otherwise stated, the chassis is presumed to be plugged in, and is changing power states between powered up and powered down.
When you press the chassis power-on button, if the chassis does not power up and the front panel LEDs do not light, it is possible for the chassis to be in a safety shutdown state. Remove the chassis AC power cord from the chassis for one minute.
Reconnect the power cord and turn on the chassis again. If it still does not power on, refer to the
Keysight PXIe Chassis Service
Guide .
The following sections describe differences in starting up the host controller PC based on the version of Keysight IO Libraries Suite installed on your system controller.
Power sequencing
When powering up the system, the chassis must be powered up first. After powering up the chassis, you should wait at least three seconds before turning on the PC. The chassis front panel temperature LED, which is on for three seconds after the chassis is powered up, provides a convenient way to measure this delay, as shown below.
Keysight PXIe Chassis Family User Guide 21
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The PC should be shut down before the chassis is powered down. This will prevent the chassis, as it is being powered down, from disrupting operation of the PC.
In brief, the PC should be off whenever the chassis is powered up or down. Because chassis modules are not hot-swappable, chassis modules should only be added or removed when the chassis is powered down.
The above power sequence does not apply to an embedded controller installed in the chassis because the embedded controller and chassis are powered together.
PC startup requirements for Keysight IO Libraries Suite
This section describes the PC startup events for Keysight IO Libraries Suite.
Improvements have been made in Keysight IO Libraries Suite that considerably simplify the PC startup process. Keysight recommends use of latest version
Keysight IO Libraries Suit.
Before describing the PC startup events for each version, two situations are described where Connection Expert, which is part of Keysight IO Libraries Suite, will not display a PCIe device, be it the chassis or a module in the chassis.
1.
If Windows can not find a driver for a device, Windows will not be able to identify the device and therefore Connection Expert will not be able to display it. If this occurs, you will typically be presented with the Windows
New Hardware Found Wizard, which will give you the opportunity to assist
Windows in finding a driver. If a driver is found, you should restart the PC and verify that Windows identifies the device (which will be evident by the lack of the New Hardware Found Wizard for that device).
2.
The other situation where Connection Expert will not display a PCIe device is in the event that, when Connection Expert is started, Windows has not yet completed assigning drivers to the devices (the chassis or modules in the chassis) found during enumeration. Connection Expert will not display modules that it cannot identify. In this situation, however, the driver exists but it has not yet been assigned to the device by the time Connection Expert is started.
Keysight PXIe Chassis Family User Guide
This situation should be very rare; if it occurs, it would be expected to occur with slower PCs. The solution for this situation depends on which version of IO Libraries
Suite you have installed and is described below. For the first-ever connection of the chassis to the PC, or after changing the chassis configuration, only a single boot of the PC is needed. However, sufficient time needs to be allowed between when
Windows is up and when Keysight Connection is started in the following figure.
The two cases described above where Connection Expert does not display the chassis or a module in the chassis can occur with Connection Expert. If the New
Hardware Found Wizard is displayed, follow the steps in the Using Connection
Expert to connect to the chassis section in the Keysight PXIe Chassis Family
Startup Guide to associate a driver with the device. If Connection Expert, does not display a particular device, click the Rescan button to see if Windows has now assigned a driver to the device, which will allow Connection Expert to display the device.
In general, if it ever appears that your chassis configuration as displayed by
Connection Expert differs from your actual configuration, click the Rescan button.
This should align the displayed configuration to the actual configuration.
Even with the latest version of IO Libraries, it is always advisable to boot the PC a second time to ensure that the PC properly enumerates all of the modules within the chassis.
Performing a chassis hard reset
A chassis hard reset refers to powering down the chassis and then disconnecting it from AC power. A hard reset is required in response to certain self test failures as described in
Self test codes and messages on page 55 . As noted in in the above
image, when the chassis is connected to AC power, the 5Vaux supply is powered, and is supplying power to certain chassis components, such as the Monitor
Processor. Performing a hard reset ensures that power is removed from all chassis components.
Keysight PXIe Chassis Family User Guide 23
To perform a chassis hard reset, the chassis should be removed from AC power for a minimum of 30 seconds, this is to ensure that the 5Vaux supply is completely powered down. The entire sequence is shown in below image.
In essence, a chassis hard reset is a system restart that includes unplugging the chassis from AC power after the chassis is powered down.
Performing a system restart
For a system with a remote controller PC, system restart refers to the power sequence shown in the following image. The remote controller PC is turned off followed by the chassis being powered down for at least one second. The chassis is then powered up followed by turning on the PC.
When the chassis is powered down using the front panel ON/Standby pushbutton or the Inhibi t signal on the rear panel DB-9 connector, the chassis is still connected to AC power. Therefore, the 5Vaux (auxiliary) supply is powered, and is supplying power to components such as the Monitor
Processor. The other chassis supplies (3.3V, 5V, 12V, and -12V) are not powered.
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If the chassis contains an embedded controller, a system restart consists simply of power cycling the chassis, which will also restart the embedded controller.
Keysight PXIe Chassis Family User Guide
