SCXI to LabVIEW communication problems

[nick5446]

I am running LabVIEW 8.0 with updated driver software and an SCXI-1000 chasis with SCXI-1102 modules and the two systems don't seem to be communicating. The SCXI setup was tested and is working fine. Any help or ideas would be appreciated.

[Travis G.]

Hello nick5446,

You should first troubleshoot your SCXI system in Measurement & Automation Explorer (MAX).  It might also help to upgrade to the latest version of the NI-DAQmx driver.  Is your DAQ device passing the self-test in MAX and can you take proper measurements using the Test Panels?  If not, then the SCXI systems are probably not configured properly in MAX.  If they do pass the tests fine, there may be an issue with your LabVIEW program and I would suggest testing with some of the DAQmx LabVIEW shipping examples found in the LabVIEW Example Finder (Help > Find Examples).  Another thought is if you are connecting multiple SCXI chassis to a single DAQ device, you will need to make sure that the chassis are properly addressed. 

Maybe you could reply with some more detailed information about exactly how your program is not working, i.e. error codes or bad readings.  Also, are you connecting your SCXI system to your computer using a DAQ device or an SCXI-1600?

Let us know and hopefully we can give some further suggestions.

Regards,
Travis G.
Applications Engineering
National Instruments
www.ni.com/support

[nick5446]

All of the test panels seem to be workinging fine, and it looks like all of the hardware is in good working order, and connected properly. As far as updating DAQmx, we are using traditionalDAQ, which has been updated to the latest driver.

thanks a lot for your help

~nick

[Travis G.]

Hello Nick,

If you can get good readings with the test panels in Measurement & Automation Explorer (MAX), that indicates that your hardware and driver software is installed and configured correctly, and that the problem lies in your LabVIEW program.  The next troubleshooting step would be to try some of the Traditional NI-DAQ LabVIEW shipping examples, which can be found in the LabVIEW Example Finder under Help > Find Examples.  You can browse for the analog input Traditional NI-DAQ examples under Hardware Input and Output > Traditional DAQ > SCXI.  I would recommend starting with the example titled SCXI-1100 Voltage.vi.  You need to make sure that you are properly addressing your SCXI-1102 module in the Channel control on the front panel of this VI.  You can find more information about how to use the Traditional DAQ functions by right-clicking them on your block diagram and selecting Help.  These VIs will throw an error if you are not configured with acceptable settings.  What errors are you receiving when you try to run your program?

I would also recommend that you consider transitioning to using the NI-DAQmx driver and functions.  These functions are much easier to program with, and usually execute more efficiently than their Traditional NI-DAQ counterparts.  What DAQ device are you using in your SCXI system?  

Also check out the following resources:

Transition from Traditional NI-DAQ to NI-DAQmx

Learn 10 Functions in NI-DAQmx and Solve 80% of Data Acquisition Applications

I hope this helps and let me know how it goes,

Travis G.
Applications Engineering
National Instruments