Getting NaN readings

[Xchus]

Hello, new guy here, I looked everywhere for a logical answer to this problem, we have 5 laptops with LabVIEW 8.2 and we are using DAQ-6024E PCMCIA cards. All the laptops have the exact same, hardware, software and drivers installed (except one that has a different video card and cpu).

The problem is that 4 of the laptops after taking data and creating around 203 files (files are created every 2 mins) the computer starts spitting NaN values instead of data (also it stops creating the files with the data), the weird part is that the laptop that has the different hardware keeps recording the data with no problems, I double checked everything (hardware, software, drivers, ran diagnostics (hdd, ram, cpu)) and still the computers spit the NaN values past 200 and so files. Any suggestions?

Thanks.

[Xchus]

I found out that now if I run the Highlight execution it would spit the error right away on all the computers. The error handler says to increase the buffer size but I can't seem to find where to change it.

[crelf]

I found out that now if I run the Highlight execution it would spit the error right away on all the computers. The error handler says to increase the buffer size but I can't seem to find where to change it.

What's the error code? Can you post your code here so we can make suggestions? If not, can you post an example written specifically to post that demonstrates the issue? Sounds like a buffer overrun / underrun, but without the error code I'm just speculating...

[Xchus]

Error -200279

[crelf]

Error -200279

Under the "Help" menu, there's an "Explain Error" item, which reports:

Warning -200279 occurred at an unidentified location

Possible reason(s):

Attempted to read samples that are no longer available. The requested sample was previously available, but has since been overwritten.Increasing the buffer size, reading the data more frequently, or specifying a fixed number of samples to read instead of reading all available samples might correct the problem.

Looks like you're sampling faster than you can get the data out of the buffer (ie: "buffer overrun").

[Xchus]

I finally have time to post a pic of the code, please look at it and tell me if you have any ideas, thanks in advance.

[Ton Plomp]

I finally have time to post a pic of the code, please look at it and tell me if you have any ideas, thanks in advance.

Hello Xchus,

the error you gave means that the data you want to read is no longer available.

Looking at you code it means that processing the data (save data through post process data) and the countddown VI take more than 2 minutes. Could you time the loop rate (tip:

)

If you want to measure only every two minutes, you could skip the countdown (I think this will generate the wait time) and set the timeout of the read DaqMX to 150 or so. Also set the #samples on the DaqMx timing VI to 2400 so it can keep 4 minutes of data

Ton

[Xchus]

I'm testing the code with your suggestions, in another laptop im trying to setup the loop timing code shown above but it spits weird numbers and spits them before the loop even finishes, suggestions? again thanks for all your help

[Xchus]

Update

Following both Ton and Jennifers suggestions I apparently fixed it. I got both computers running for about 12 hours one taking 1200 samples and the other 3000 samples, however I only added the timeout to DAQmx read and the Available Samples per Channel read node. I will continue testing. Again thanks for your help.

[crelf]

I got both computers running for about 12 hours one taking 1200 samples and the other 3000 samples...

That's great news! :thumbup:

[Xchus]

The error showed up again after the 710th file (~ 24h of data), but the indicator doesn't show any remaining samples in the buffer, now I'm clueless.

I got to take at least 72h of data. I made some changes to the code, but if anyone have any other suggestions feel free to post them. Thanks!