AI. to new Labview 18

[dannygzolez]

Hello, 

In the attached image I am trying to transition from Labview 7 to Labview 18. The AI Read One Scan no longer is functioning and I can not figure out how to make it function properly in Labview 18. Any suggestions? I've read in many places that DAQmx is able to perform the function but I have had many failures attempting to get it to operate. 

[RavensFan]

Search DAQmx in Example Finder.

Read Learn 10 Functions in NI-DAQmx and Handle 80 Percent of Your Data Acquisition Applications

[Bob_Schor]

Does your Device (in MAX) allow you to take a Single Sample on Demand?  That's the equivalent of Read One Scan, I believe.

Bob Schor

[dannygzolez]

Yes it does. However when reconnecting to the new DAQmx all wires are broken.

[RavensFan]

Then read the descriptions as to what is broken.  You probably need to delete a control or constant, create a new one off the DAQmx subVI connector panel, and select the correct channel or values.

[mcduff]

This is @KevinPrice territory, but I am guessing your old VI uses the old DAQ functions, I do not remember when DAQmx was introduced. If that is the case you would need to rewrite code but first see if your instrument is compatible with DAQmx.

mcduff

[Bob_Schor]

I believe that LabVIEW 7.0 had DAQmx -- if so, it is at least 12 years old (if not older!).

Bob Schor

[mcduff]

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@Bob_Schor wrote:

I believe that LabVIEW 7.0 had DAQmx -- if so, it is at least 12 years old (if not older!).

Bob Schor

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But the missing function is from traditional DAQ. See what the first knight said

https://forums.ni.com/t5/LabVIEW/How-to-use-AI-Read-one-scan-vi-in-Labview8-0/m-p/430768/highlight/t...

mcduff

[Kevin_Price]

Heard someone say my name...

Yes, "AI Read One Scan" is a function from the old (old, *very* old) traditional NI-DAQ driver.  I think it was an all-in-one that combined configuration and software-timed read of a single sample (then referred to as a "scan", which was once a more common way to help distinguish that there might be data for multiple AI channels in that one single scan / sample)

Labels in the screenshot identify an E-series board which have been supported by both traditional NI-DAQ *and* DAQmx.  I don't know if the very latest versions of DAQmx still support such an old DAQ device.

I would advise that you *first* follow Bob Schor's advice in msg #3.

Then you might look at the shipping example "Voltage - SW-Timed Input.vi" to get a headstart on how you work with your DAQ devices using the DAQmx API.   You might want to use the dropdown menu on DAQmx Read to change *away* from waveform output to a simpler 1D array.  In software-timed mode, the extra timing info in a waveform isn't particularly helpful.

- Kevin P

P.S.  I remember LabVIEW 7 and DAQmx being no later than 2005.  I was an early, though partly reluctant, adopter of DAQmx due to (1) multithreading which supported parallel access to the driver, (2) purchase of newer M-series boards with hw-timed DIO that were *only* supported by DAQmx.