LabVIEW

cancel
Showing results for 
Search instead for 
Did you mean: 

Combining/Synchronizing Digital and Analog Data

Hi Everyone!

 

I am using a NI 9189 with the NI9205 and NI9425 to measure analog and digital data respectively. 

What I want to do is create an array with both the analog value and digital data. The problem I am having is the I am doing NChannels NSamples for the Analog Read Task and NChannels 1Sample for the digital task. Due to this difference, when I concatenate the arrays it only shows the digital state once per loop iteration. I want them synchronized. Does anyone know how to fix this?  I tried messing around with NChannels NSamples with the digital task, but I was having difficulty. 

 

Any help would be appreciated!

1234.PNG

 

C56.PNG

 

0 Kudos
Message 1 of 3
(2,162 Views)

So I just found this example online, but I am still having problems. It errors saying DAQmx read does not match the type of channels in the task. 

 

https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z0000019PBVSA2&l=en-US

 

error.PNGbuh.PNG

 

 

0 Kudos
Message 2 of 3
(2,147 Views)

I don't have experience with Compact DAQ, but have used USB and PXI DAQ devices.  What happens if you write a routine that does just one of these?  Does Analog alone work?  Does Digital alone work?  If both work stand-alone, then the problem is combining them.

 

When I've configured DAQ input, I always wired the Number of Samples in the Timing function (rather than assume a default).  I also wired this to the Read function (to force it to read all of the points) -- I never used -1 (and so far haven't had a problem doing this).

 

So do some experiments, see precisely where the error is occurring, and see if specifying # of samples and using the same value for the Timing and the Reads helps.

 

Bob Schor

0 Kudos
Message 3 of 3
(2,140 Views)