VXI support under LabVIEW for Linux

[Kevin Valentine]

A potential client contacted me regarding a small project using VXI hardware under Linux. I'm considering using LabVIEW for Linux but I'm not too clear on NI's VXI driver support and whether they have a VI library for the particular hardware. I contacted NI tech support over the phone but they didn't have any answers. BTW, I've used LV with PCI and ISA DAQ boards under Windows and Linux but I've never used VXI.

Here is the hardware in question:
PCI/VXI-MXI-2(8026) - PCI to VXI bridge
VXI-AO-48XDC - 48 channel analog output board
VXI-MIO-64XE-10 - multifunction DAQ board

Anyone know what's involved in building a LV app for this system under Linux, i.e. what's NI's HW driver and LabVIEW support?

-kevin

[Shawn B.]

Kevin,

National Instruments has NI-VXI for Linux. The driver provides support for the PCI/VXI-MXI-2(8026), and VXI embedded Controllers. The NI-VXI driver also provides the programming API that will allow you to communicate with the VXI boards in your system.

If you have never used VXI before I should note that it is different from using a PCI DAQ card. 

The LabVIEW for Linux system requirements can be found here. I should note that LabVIEW will work on the 2.6 kernel, however since you are looking at NI-VXI you will need to use the 2.4 kernel anyway.

Hopefully this answers your question, but if you have any further questions feel free to ask!

Shawn B.
National Instruments

[Kevin Valentine]

Thanks Shawn.

I'm looking through the Short Tutorial on VXI/MXI (AN030) right now. Will I have to buy the NI-VXI/VISA Support Kit? (http://sine.ni.com/apps/we/nioc.vp?cid=10603〈=US})

Is there a library of LV VIs to use for specific VXI DAQ hardware or do I have to make my own with low-level VISA functions?

-kevin

[Shawn B.]

Kevin,

I forgot about the DAQ boards you wanted to use. Unfortunately these boards are obsolete, and no longer supported by NI. In Windows you would normally use NI-DAQ 6.9.3 to communicate with the boards. In Linux there never was an official driver for the cards. I thought initially that you could use develop you own low level functions like you mentioned, and you possibly could, however I just looked at the manuals and there is no documentation about what registers to use or messages to send.

Hopefully I didn't get you started in the wrong direction with my previous post.

Shawn B.
National Instruments

[Kevin Valentine]

Sorry about my bad links in this and the other post. Almost every message forum I use has a different way of inserting links...

Thanks for your help. So to summarize, this client can only use Windows with NI-DAQ 6.9.3.

I contacted Frank Hess of the Comedi project. He seemed confident that Comedi could support VXI hardware if he had the register-level docs for the PCI/VXI-MXI-2(8026) board. He expressed an interest in this too because he has a VXI project coming up that uses the MXI-2 board. How difficult is it to get the register-level docs for at least the MXI-2 board?

[Shawn B.]

Kevin,

The PCI/VXI-MXI-2(8026) is supported by NI-VXI/VISA in Linux. The VXI-MIO-64XE-10 and VXI-AO-48XDC need NI-DAQ 6.9.3 in Windows and are no longer supported by NI. Unfortunately there are no RLP manuals for these boards. You can always check http://www.ni.com/manuals to see what RLP manuals we do have.

Shawn B.
National Instruments

[Kevin Valentine]

The client wants to use a 2.6.x kernel so I guess that rules out MXI-2 interface support too. I checked the link to the manuals but for VXI there's mostly simple start-up guides.

It's strange that NI wouldn't want to provide the register-level docs, especially for obsolete boards. When the boards become obsolete are certain documentation thrown away or locked up? Does NI need me and the client to sign a non-disclosure agreement? There must be a solution to this, other than forcing the client to switch to Windows.

[Shawn B.]

Kevin,

The reality is that we never developed this documentation for external use and do not have the resources to do so now. The developers here generally work from internal chip-based documentation that was used in the development of the board, and later format this into an external documentation.

The DAQ-STC Technical Reference Manual would be relevant for the MIO board, however the EEPROM information is not available for this board.

Shawn B.
National Instruments

[Kevin Valentine]

Thanks for your time Shawn. This has been an enlightening discussion! I'll talk with the client about the possiblity of upgrading their hardware, if they choose to stay with Linux.