DAQ acquire continously

[Nghtcrwlr]

I have two Analog inputs ( voltages) and a Counter (for which i use a mechanical switch). I need to acquire data for 10 sec continoulys with 1000samples per second.This VI waits till it acquires first 1000 samples and then stops. How is it possible to acquire continoulsy the data ( i.e 1000 * 10 = 10'000 data values. Also I need to see the graph in real time. i.e when i change the input voltages, the graph should also show the change in real time. See attachment for the VI
Any ideas? pls

[JarleEkanger · Accepted solution]

That's because you use the "Last value" tunnell mode for the acquired data. Change it to indexing.

Using finite samples will have the DAQ read VI sample N samples before they are output. Changing to continuous sample mode and setting the DAQ read to read single samples outputs data real time. To display it you need to change your graph to a chart, and move it inside the while loop. Use timing to stop the loop after 10000ms.

I highlighted the changes I made to your VI in yellow, see attached pic.

[Nghtcrwlr]

Thanx Jarle

[NunoSilva]

I'm kind of new using DAQs, with Labview, and came across with a problem I can't find a way to fix it.
I'm using an old DAQ NI PCI-6013 with an also old computer (dinosaurs), but they (don't ask who are they) will not provide me with
newer stuff. I read (analog to digital convert) 15 sensors using a DAQ Assistant and, directly or after some signal processing, send
data to a Write To Measurement File vi. The DAQ assistant is configured so that Acquisition Mode = Continuous, buffer size (Samples to
Read) = 800 and Rate = 6KHz. The Write to Measurement File is configured to "Save a series of files" with File format as Text(LVM), No headers and "One column only" for Time.

Everything seemed to be working fine but when analyzing the data I noticed that there was a cut in some data. It is something like the DAQ
stopped acquiring data from some sensors. Researching led me to find out that the cuts happen at some buffer size ticks. I attached a
figure where you can see an example of what is happening. Series 1, 2 and 4 signals go to zero, instantly, at sample number 1600 (2 x 800) but Series 3 signal continues to be acquired. But then, Series 3 signal also goes down, this time at sample 2400 (3 x 800). Why does this happen?

I tried many combinations of configurations like, N Samples instead of continuous, other rates and buffer size or number of samples to
read, and the issue still occurs and always at multiples of "N Samples to read" (or buffer size).