NI PCI-6031E wil not acquire data from channels 16-63 using OSX, LV7, and Daqmx Base

[bradj0]

Hello-

I can already guess the response of my question will be "Sorry, unfortunately not all funcationality is implement for the 6031E in OSX under the Base drivers...."

I upgraded my data acquistion from OS9 and LV6 to OSX and LV7 and so far it has been nothing but a nightmare. Turns out about 25k of hardware I have sitting around isnt compatible and might never be again. I've worked around so many problems already it is getting ridiculous and the only reason I havent reverted back to LV6 is ... ? stupidity I guess. After I switched to the new version, I rewrote my software in mx base and everything seemed OK although it is much slower in both loading and effective data collection rates. I am now scaling everything up and need the rest of the channels on my cards (64 SE). It turns out that I am unable to acquire data in either SE or DI mode for any channel above 15. I tried a second 6031e card to the same result. Is this a known problem? can anyone verify if these channels work on other installations? Is it finally time for me to revert back to LV6 to get full functionality ?

Brad

[bradj0]

I just remembered, I have a sync cable between the two PCI-6031E cards in my Mac. I couldnt imagine this would mess things up. I will remove the cable and try again but not optimistic.

[bradj0]

I removed the PFI cable and no improvement.

I am testing the system as follows. I have a sine wave generated from analog out 0 (AO_0). I am software timed reading AI channel X on the same card. To test differential mode, I connected AO_GND to the -Ain and AO_0 to Ain+ of whatever channel I am testing. For NRSE mode testing, I connect AO_GND to AI_SENSE and then just connect AO_0 to whatever channel I want to test. In either case, I cannot get any channel above 15 to respond but 0..15 work perfectly.

Brad

[Tom_W_[DE]]

Hi Brad-

It sounds like you may be experiencing the problem discussed in this thread.  There is a patch VI available that should address the problem.

Hopefully this helps-

[bradj0]

Hi thanks for the link. I replaced the VI and now channels 16-63 are "on" but they have voltage offsets. If I generate a 0-5 V sine wave from AO-0, I get 0-5 on channels 0-15. However on channels 16-63 the sine wave amplitude is 5 volts but the offset is not zero, it seems to be drifting around. Eg. I will get a sinewave from 1-6 volts. Seems like maybe the channels are set to RSE and should be NRSE. I will look through the VI you suggested and try to find the problem... but if anyone has already fixed this that would be great.

brad

[bradj0]

The offset is only occuring in NRSE mode... does not occur in diff or RSE modes.... and again, only on channels 16-63.

Brad

[Tom_W_[DE]]

Hi Brad-

Is it possible that you are referencing the upper channels to AI SENSE rather than AI SENSE 2?  For NRSE channels above ai15 you must use AI SENSE 2 (pin 75) as the negative reference point.

Thanks-

[bradj0]

Yes I was using AISENSE1 and using AISENSE2 fixed the offset, thanks. Is there any problem shorting AISENSE1 and AISENSE2 together? I am driving 60 sensors from AO_1 and then measuring the voltage response of the sensors, where the voltage is all referenced to AO_GND (because they are driven by AO_1).  Thus, I will be shorting AISENSE1 and AISENSE2 directly to AO_GND, close to my sensors.

Brad

[Tom_W_[DE]]

Hi Brad-

There should be no problem shorting the two AI SENSE pins- actually, they are already effectively shorted because of the common reference point as you mentioned.  Regardless, I'm glad to hear you're up and running now.

Thanks-