Query interrupted error while acquiring waveform from TDS 3014B

[millepede]

Hi,

I am using LV8 to perform single channel data acquisition from a tektronics TDS 3014B oscilloscope. I am using the single channel acquisition program that come as an example with the labview driver. When run the program I get the following error

TKTDS3K Error Query;
Instrument reports the following:
410:  Query INTERRUPTED;
0:  No events to report - queue empty

I tried to debug the program and found that the Read Waveform subvi generates the error. This subvi has another subvi called fetch waveform.vi which does the actual low level communication with the instrument. I am attaching screenshots of these two subvi as well as of the front panel.vi after I do the acquisition. Could someone please help me debug this error.

Thanks in advance.

-Anand

[smercurio_fc]

duplicate post

[millepede]

Sorry about the duplicate post. I thought that the Instrument control section was probably more appropriate for posting than the Software section and hence the duplication. I tried to delete the previous post but couldn't figure out how to.

-Anand

[Dennis_Knutson]

You did not attach the top level VI. Your front panel shows a PSD graph but the view of the block diagram does not show this indicator. What is the actual top level VI doing besides calling the scope VI?

[millepede]

I am attaching the top level vi. It is very big so I couldn't get the entire screenshot at once. So it is in two lines. I am attaching another vi that uses the fetch waveform vi and encounters the same error.

Thanks,

Anand

[Albert.Geven]

Why not attach the vi, instaed of a drawing?

[millepede]

good point....here are the top level vi's. I think these come with the instrument drivers available at http://sine.ni.com/apps/utf8/niid_web_display.download_page?p_id_guid=014E9F890ACE6DA0E0440003BA7CCD71

-Anand

[Dennis_Knutson]

Didn't realize that you were using one of the shipping examples. A query interupted usually means that while there is still data in the transmit buffer, the instrument receives a new command. You want to make sure that the record length of the acquisition matches the number  of samples you are requesting. In other words, if you set the acquisition for 20000 samples, you need to request that number. If you only request 10000, I think you will get that error.

[millepede]

Where do I specify the number of samples to be acquired? The only relevent fields I can find are the record length and the start and end points of the record. I have record length = 10000, start of record = 1 and end of record = record length.

Thanks,
Anand  

[Dennis_Knutson]

It looks like the record length (number of samples) and number of records to read is matching. Sorry, I don't have that instrument available to see what might be causing the error.