PXI

[SCXI_and_MS_2k…]

Is it possible to use network devices (cDAQ-9188) with a PXI Real Time system and Labwindows/CVI?

[cZach]

Unfortunately, you cannot use and Ethernet cDAQ chassis or any USB cards/chassis with RealTime on a PXI. The PXI does support LabWindows/CVI RealTime programming with DAQmx, but this will only work with PXI cards.

Here is a list of what our USB/Ethernet hardware supports:

http://www.ni.com/white-paper/6913/en

And here is a list of devices that support RealTime (Phar Lap):

http://www.ni.com/white-paper/6910/en

[SCXI_and_MS_2k…]

Thanks for the reply.

I am moving from Windows/Measurement Studio to PXI RT/CVI and the one thing I'm losing (other than low cost!) is distributed IO.  We mount 9188s in the test cell and pump the data back digitally so we can minimize noise.

Perhaps we need to make a RIO solution that pumps data via TCP/IP back to the PXI?

[cZach]

You have a few options for using RIO with a PXI Real-Time chassis. TCP/IP would be the best way to communicate with a cRIO over Ethernet. This would require programming in LabVIEW (or a C dll called from LabVIEW) for the cRIO as it does not support LabWindows/CVI. *Exceptions to this are the cRIO-900x and 908x series which run Phar Lap, the RT OS that works with CVI.

An alternative would be to use one of the PXI R Series cards (FlexRIO) that have onboard FPGAs and can be used directly in a PXI chassis.

[SCXI_and_MS_2k…]

OK Zach, this is news to me.  I had a support request open and the consensus among those on your end was that RIO was not an option.  Do the RT RIO systems run the same OS as a PXI RT system?  This would be really good news for me. 

Also, if this is the case, how would I daisy chain chassis?  Would I need to use TCP IP or is there an easier method (not that TCP/IP is difficult, but that I'll have to have someone else do the LabVIEW programming since my time is better spent on CVI)?  We often require 3 or more 8 slot chassis.

Thanks!

[cZach]

Hi Michael,

There are some other options that might be easier to use with PXI. The PXI R-series cards would give you access to FPGA programming without another chassis. The MXI-Express RIO chassis would give you an easier way to interface with your cRIO modules (http://sine.ni.com/nips/cds/view/p/lang/en/nid/208314).

You may want to call in to discuss the best option for your situation in more detail. You can speak with an Account Representative about the setup options for your system at 888-280-7645.

Most cRIO chassis do run the VxWorks operating system, which does not support LabWindows/CVI programming. PXI RT chassis run the Phar Lap operating system which does support text-based programming. I linked a KnowledgeBase article below that details the operating systems on our Real-Time Controllers.

http://digital.ni.com/public.nsf/allkb/35F1FD98520D6E0E8625783A005AF557?OpenDocument

You would also need to use cRIO chassis that have two Ethernet ports to make sure you could daisy chain them together. This would narrow your choices down to the newer cRIO-9081 or 9082 RT systems.

http://sine.ni.com/np/app/main/p/ap/crioctrl/lang/en/pg/1/sn/n25:controller,n24:cRIO/

TCP/IP would be the best way to communicate between cRIOs and the PXI chassis if you choose this option.

[SCXI_and_MS_2k…]

You've been an excellent help so far.  I don't think I should need to call if you can answer one more question.

I'd use the RT RIO system to replace the PXI system, and I'd use remote RIO chassis programmed in LabVIEW to send data through TCP/IP for any expansion beyond the intitial 8 slots of the RT system. 

The one question is have is, are the CAN and RS232 cards for PXI and RIO programmable using CVI?

Thanks!

[cZach]

The NI-CAN driver page (http://joule.ni.com/nidu/cds/view/p/id/2646/lang/en) lists the PXI cards that are supported in Windows and LabVIEW Real-Time. These should be usable with CVI. The CAN cRIO modules require using the FPGA on the cRIO, but there is limited support for FPGA in LabWindows/CVI.

The NI-Serial for Real-Time readme lists all the supported hardware for that driver (http://download.ni.com/support/softlib//serial/Serial%20NickD/WIN3/NI-Serial%203.7/3.7%20niser%20Rea...) which covers the PXI and cRIO options for RS232. The NI-Serial driver also supports CVI and Real-Time, so you should be able to program for both of these options. The RS232 modules also do not require the FPGA on cRIO, so you could program directly from the Real-Time OS. Hope this helps!

[cZach]

To update this info, DAQmx 9.6 and LabVIEW Real-Time 2012 now allow you to use a USB cDAQ chassis with a Real-Time PXI system.

[SCXI_and_MS_2k…]

Does this also apply to LabWindows CVI?