DAQ Assistant changes from LV 8.0 to 8.2?

[Dr. Ed]

I recently wrote a simple VI to acquire data from 4 LVDT's and one full-bridge pressure transducer.  The machine I created the VI on is running LV 8.0, and I used the DAQ Assistant to configure the input channels.

I then copied the VI onto the actual computer that is used in the field, which is running 8.2.  My VI would not run on that computer due to a DAQ Assistant error.  I have my channels set to acquire a sample at a given frequency (5Hz, variable from the front panel), which works on 8.0 but on 8.2 the error message informs me that I have to either choose "Acquire N samples" or "Continuous" sampling.

Did something change from 8.0 to 8.2 with the DAQ Assistant?  I really need to be able to sample at a given frequency, which I can adjust as needed during the acutal event.

[Ed W]

Hi Dr. Ed,

Thank you for posting to the NI forums.  The DAQ Assistant installs with the DAQmx driver, not LabVIEW.  Therefore, the LabVIEW version that you’re using should not affect this express VI’s ability to setup sampling rates for your device.  Instead, the problem is probably related to the DAQmx driver or the actual device that you’re trying to use.

1.  What devices are you using on these computers?  If they are not of the same type, then perhaps the problematic PC’s device is just incapable of acquiring data in this way.

2.  What version of the DAQmx driver are you using on each computer?  If it is not the same, then this could be another source of the problem that you’re seeing on these different computers. 

3.  Make sure that the name of your device, within Measurement and Automation Explorer (MAX), is the same from PC to PC.  If you’ve hardcoded the name of the device into the DAQ Assistant, you may need to change it on the new computer.

I hope this helps.  Post back if you have any further questions.

Ed W.

Applications Engineer
National Instruments

[Dr. Ed]

Thanks.

I wrote and tested the VI and hardware on a desktop computer then moved everything to the laptop.  It worked on the desktop, but not on the laptop, so I don't believe it to be a hardware issue.  I uninstalled LV8.2 on the laptop and installed LV8.0 and everything works now.