error -200877

[bonosA]

When I do

 DAQmxErrChk DAQmxReadAnalogF64(taskHandle1, numSamps, -1, _
                DAQmx_Val_GroupByChannel, data(0), totalSampsAllChannels, sampsPerChanRead, ByVal 0&)

where numSamps  = n * 250, n integer, for certain values of n there is no problem, like n = 1 or n = 5.

But if I use n = 3, or 4 or 7 (and some others), I get error -200877. The message box has a long descriptiion in it, but it is chopped off. It goes like this:

Requested Every N Samples Interval is not supported for the given Data Transfer Mechanism and buffer size. To keep DMA as the data transfer mechanism modify the bufffer size and or the Every N Samples Interval so that the buffer size is an even multiple of the event interval. To keep the same event interval and buffer size change the. (and here it gets chopped off).

I did try making the buffer size an even multiple but that didnt resolve the issue. I wanted to try the second alternative, but of course I have no clue what it is. I looked in the NI error files but there is even less info in there.

Any help would be appreciated.

thanks,

saroj  

[wildcat_600]

Hello saroj,

I have been unable to find the full exact error message that you are looking for.  In some cases depending on your UI you can select the error code text to copy it and even if the text is cut off it can still be selected.  So you might try that to see if you can view the entire error description. 

Can you let me know what device and software you are using?  Also if it is possible could you post a screenshot of the error?  To take a screenshot just hit the Print Screen key on your keyboard and then paste the image into Paint and save it.  Then you can attach it to your next post. 

Thanks and have a good weekend,

Brian P.
Application Engineer

[wildcat_600]

Hello Saroj,

I know you are working with another Applications Engineer on this issue, but I wanted to post the entire error description for completeness.  It is attached below.

Have a good day,

Brian P.
Applications Engineer
National Instruments

[bonosA]

many thanks, Brian. It helps a lot to know what the complete message was.

Brian K has also been working on it, doing an outstanding job and I believe he's resolved the issue. I will test it out at the lab today. I appreciate your input. You guys do great work.

saroj