LabVIEW Communications 2.0 and Linux RT connection

[jrewienski]

Hello!

I'm trying to run this project on my setup:
http://forums.ni.com/t5/Software-Defined-Radio/NI-NS-3-LTE-Application-Example/ta-p/3572116
following those instructions:

http://forums.ni.com/ni/attachments/ni/3017/663/1/installation_guide.pdf

I have trouble with section C 2.3, which covers connecting LabVIEW Communications 2.0 (hosted on Windows7 PC) with USRP Rios via NI Linux RT (hosted on PXI).

Unfortunately I do not have access to a PXIe-8135 or PXIe-8880, so I've used available PXIe-8840. The Linux RT seems to be running fine, as using lsni lists all my hardware.

I have registered the PXIe-8840 in LabView Communications as instructed, and it seems to connect to all the remote devices (PXIe-8840, USRP-2954R and CPS-8910 are automatically discovered and marked as connected) - screenshot attached.

When I try to run LTE Host DL.gvi, after compilation, I get an error saying:

"Error -63192 occured at Open FPGA VI Reference in LTE DL Host Initialization.gvi" (screenshot attached)

 I tried running the same project omitting the PXIe-8840, by running it on Win7 PC with NI PCIe-8381 card and connecting via CPS to USRP and it worked just fine.

The question is - what causes the error? Is it an incompatible PXIe version? Should the chassis be also connected via ethernet? Is something wrong with my LinuxRT? Maybe it's caused by the CPS (I do not think so, as it works when omitting the PXI)?

I would like for my final setup to be:
1) Win7 PC for LVComms

2) PC + NI PCIe-8381 card, hosting NI Linux RT connected to two NI USRP-2954R (USRP RIO) via NI CPS-8910 (Switch Device for PCI Express)

Is it even possible to connect such setup?

EDIT:
The section when I had an error was C 2.3, not D - my mistake.

[DECONN]

Hi jrewienski,

I hope I can offer some help here. See my comments below:

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@jrewienski wrote:

I have trouble with section D, which covers connecting LabVIEW Communications 2.0 (hosted on Windows7 PC) with USRP Rios via NI Linux RT (hosted on PXI).

Before moving to section D, was the test described in section C.2 successful? The attached screenshot looks more in line with section C than section D.

Unfortunately I do not have access to a PXIe-8135 or PXIe-8880, so I've used available PXIe-8840. The Linux RT seems to be running fine, as using lsni lists all my hardware.

I have registered the PXIe-8840 in LabView Communications as instructed, and it seems to connect to all the remote devices (PXIe-8840, USRP-2954R and CPS-8910 are automatically discovered and marked as connected) - screenshot attached.

We have tested the NS-3/LTE project with the 8135 and 8880. These are officially the supported RT targets for LabVIEW Communications at the moment. You can find these listed in the manual here. That said, they are pretty similar architectures so it may be possible to get it working with some tinkering but it could be an issue that you run into.

When I try to run LTE Host DL.gvi, after compilation, I get an error saying:

"Error -63192 occured at Open FPGA VI Reference in LTE DL Host Initialization.gvi" (screenshot attached)

This sounds like the RIO name of the USRP is not configured correctly (top right corner of the GUI). Check the hardware names in the System Designer. Maybe first try to connect the USRP directly to the PXI chassis without the switching box.

 I tried running the same project omitting the PXIe-8840, by running it on Win7 PC with NI PCIe-8381 card and connecting via CPS to USRP and it worked just fine.

The steps described in section C will work just fine on a regular PC because the regular LTE Framework does not depend on NI Linux RT. The NS-3/LTE project described in section D will not work.

The question is - what causes the error? Is it an incompatible PXIe version? Should the chassis be also connected via ethernet? Is something wrong with my LinuxRT? Maybe it's caused by the CPS (I do not think so, as it works when omitting the PXI)?

I think the above may help narrow this down.

I would like for my final setup to be:
1) Win7 PC for LVComms

2) PC + NI PCIe-8381 card, hosting NI Linux RT connected to two NI USRP-2954R (USRP RIO) via NI CPS-8910 (Switch Device for PCI Express)

Is it even possible to connect such setup?

Currently, only a PXI controller can used as a target for NI Linux RT. A regular PC/laptop will not work. Also, you can check against the manual for additional supported hardware found here.

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[jrewienski]

Hi DECONN,

Thanks for your reply,

1) I've made a mistake, as You have noticed, the error I run into was in section C 2.

2) I hoped, that since it is similar architecture, it would run on our PXIe-8840.

3) The USRP RIO connected via switch to a PXIe-8840 running Win7 or PC running Win7 (with PCIe-8381 card) is automatically discovered and labeled RIO0 (it can also be called by CPS1Port1Dev1). The LabVIEW Communications discovers the whole setup (PXIe-8840, switch, RIO/s) and labels RIO as RIO0. That mentioned, I have tried both RIO0 and the CPS1Port1Dev1, but I am still getting the same error mentioned before.

[DECONN]

Yea, I would just do a verification without the "switch" but I think it may be in the controller image for that model. I did a quick test with a similar setup but using an 8135 (and no "switch", just MXI). It seemed to work fine with the 2.0 LTE project. I haven't been able to replicate that error yet with my setup. Also, make sure that you have at least NI-USRP 15.5 installed for using the 2954R.

[jrewienski]

I have tested the solution with PC+switch+USRP and it worked fine. I have the drivers NI-USRP 16.1.

Unfortunately, I cannot check the solution PXIe-8840 + USRP without the switch, as I only have PXIe-8384 available (which has MXI x8, not x4) - actually that was the reason why the switch was bought. 🙂

We are currently waiting for a delivery of PXIe-8880 and NI PXIe-8374, so we might be able to find the exact source of the problem.

Anyway - what is the difference in the image for those controllers (PXIe-8880, 8135?). What could be done to adjust the image (or distribution) to PXIe-8840? The architecture seems very similar, I do not understand where is the problem. Maybe it's the LabVIEW Communications 2.0?