USB 6008 input/output test failing

[bigdawg25]

OK I am posting this for third time but everytime I go back to forum homepage, I am not able to find my post. If by any chance I am creating duplicates than my apologies.

Iam trying to test the USB-6008 I just got, and decided to hook up the analog out to analog input and see it using labview VI.the wiring were done as:

http://i284.photobucket.com/albums/ll5/bigdawg6/usb%206008%20wiring_zpss2b7hql9.jpg

the problem is that the labview VI wasnt doing anything, so I go to NI Max and try and see it in test panels. But I keep getting 1.4V consistently as my analog input value even when I am changing my analog out value:

http://i284.photobucket.com/albums/ll5/bigdawg6/aio%20screenshot_zps9beiimbj.png

the analog output is working fine since I hooked it up to my multimeter and I can see the voltage I see on this test panel:

http://i284.photobucket.com/albums/ll5/bigdawg6/ao0%20screenshot_zpsqpei37bw.png

I created an input/output tasks; the screenshots of them are:

http://i284.photobucket.com/albums/ll5/bigdawg6/task_ao_zpsykmvczew.png

 http://i284.photobucket.com/albums/ll5/bigdawg6/task_ai_zpsix5se9yg.png

I am pretty fustrated by all this since I am unable to get to my actaul project. I know that 1.4 V value is coming from the device itself; since in the manual it says "internal resistor divider may cause the terminal to float to approximately 1.4 V when the analog input terminal is configured as RSE" but the funny thing is I am using this in differential mode so I dont know what to do and any help is appreciated.

BTW, I did a google search, and there are other tutorials onlune which seem to be doing exactly what I am doing and they seem to making it work fine; so I dont know what else to do.

[Dennis_Knutson · Accepted solution]

Please don't host images on some odd third-party site. Attach them to your post.

I don't understand what you have done. The 6009 can only output an rse signal so configuring the input for differential does not make much sense. If you want to measure something differentially, try a simple battery.

[bigdawg25]

my apologies for using a third party image hosting website, I didnt know its frowned upon. I tried to run it as RSE right now, but it still doesnt work. I am trying to follow this tutorial:

http://techteach.no/tekdok/usb6009/

The VI I am using is: http://techteach.no/tekdok/usb6009/files/ao_ai.vi its not letting me attach this here.

even when I am attaching source of other signals, the analog input never seems to read that, and keeps returning 1.4V value regardless of source of input. I have not put AA battery terminals across and seen if it can read that value or not since I am concerned if too much current might flow to the DAQ but if you suggest, I can try it and get back on here reporting the results.

[Dennis_Knutson]

Can you describe the exact pins you are using for input? Please don't attach a link to some other site.

[bigdawg25]

I had connected AO0 (14)  to AI0 (2) and GND (13) to AI4 (3). My VI was changing the output of AO0 and I could visualize that in AI0. I went back to the NI-DAQmx tasks and editied my voltage input task, in the terminal configuration column from "differential" to " "let the NI-DAQ choose" and that seems to make my VI run fine.

Thanks for reminding me that setting it to differential couldve been the source of the error.

[Dennis_Knutson]

Letting the driver choose can be problematic if or when you change DAQ devices. It's better, in my opinion, to explicitly select the type of connection.