Detecting chassis is powered up

[Les__Bartel]

What is the proper way for my LabView 8.0.1 application to detect that my PXI chassis is powered up?  At first I was checking the status of a switch topology initialize vi.  But to my surprise, if the chassis was powered up and then the laptop controller powered up and the the chassis powered down, the switch initialize would be successfull!  I want to be as user friendly as possible.  While I can train a user of the system, I am skeptical that the trained user would be able to train another user properly and that user train yet another user....

[minh.tran@ni.com]

Good afternoon Les,

Thanks for contacting National Instruments with your issue, we'll try our best to resolve it for you as quickly and efficiently as possible.

I'm assuming you're connecting to your chassis via a MXI or Starfabric connection since you didn't specify.  Both of these products serve as a PCI-to-PCI bridge, effectively extending the amount of PCI devices that can be connected to your laptop.  This is transparent to LabVIEW and actually occurs at the OS level, "fooling" the computer into thinking it has more PCI slots than it actually does. 

Unfortunately, this means that there is no direct way I can think of to programmatically detect if the chassis is indeed powered on.  The best approach I can think of would be to attempt to reset your switch devices with the niSwitch Reset.vi.  There should be no reason that a reset can be successful if the chassis is off.  You would then of course programmatically handle that by suprressing the error Clear Errors.vi and then moving along with your program accordingly under the assumption the chassis is powered off.

Best of luck with your project.

Sincerely,

Minh Tran

Applications Engineering

National Instruments