How can I trigger one 5v signal and DAQ assistant with the DAQ assistant

[develop0618]

I plan to trigger one square 5v signal to a camera(simulate signal/daq assistant2) by NI-USB6259 and begin to record DAQ assistant(DAQ assistant3) by other DAQ assistant(different wave gauge)

but the trigger do not work ,there still have Time difference every test，not trigger in same time every test

how can I fix it,thanks for helping

[NIquist]

You will find that most of us never touch the DAQ Assistant and will recommend that you learn the real DAQmx functions.  In your case where you need to synchronize signals you probably have no choice since you will need to access triggering that is beyond the scope of the Assistant.  Especially useful when using a powerful DAQ card like the 6259 you have. 😎  Using the DAQ Assistant with that card is like putting training wheels on a Suzuki Hayabusa!

If you want better help I would also suggest that you do a Save For Previous Version... and post your VI in LabVIEW 2018 or earlier so that more of us can open your code and take a look...

[develop0618]

Thank you for your reply,how about the trigger part，if i don't used DAQ assistant(ex.

create a signal in labview  simulate signal) ,is the trigger time still have a chance that have time difference in each event?

[NIquist]

Can you show us a timing diagram of what you're trying to achieve? 

The triggering functions of the DAQmx primitives (the functions in the palette) are far more powerful than anything you can do with the Assistant.  Plus, I will admit that I have never bothered to learn the details of any of the "Wizard" tools that NI recently added.  I learned DAQmx after using Traditional DAQ for years and it's fantastic.  I generally look through the Example Finder for something that is similar to what I want and then modify it for my specific needs.

[develop0618]

After the trigger，the wave gauge data show as the figure,Same trigger with the same condition, I'm hope it can be the same time or less time different(<0.03)

I have never bothered to learn the details too, but this is Slightly new for me, but thanks for your recommend, I will focus on that , try to make it better

[Bob_Schor]

Do Not Use the Dreaded DAQ Assistant (a.k.a. the DDA), and especially Do Not Use its Evil Twin, the Dynamic Data Wire, for anything other than trying to convince a Newbie to whom you want to sell LabVIEW as "So easy even a beginner can acquire data" that LabVIEW is "so easy even a beginner can acquire data".  [That statement is, at least, partially true -- you can acquire very simple data with the DDA, but linking acquisitions and doing "useful things" with the Data requires a little bit more).

Do a Web Search to locate and download "Learn 10 Functions in NI-DAQmx and Handle 80% of Your Data Acquisition Applications" (I think that is the correct title ...).  Skip over the section about the DAQ Assistant and learn to use DAQmx functions and good LabVIEW Programming to do what you want.

Bob Schor

[develop0618]

Thanks for your reply, I will try to work on it

[develop0618]

I have tried to fix the problem but a new problem has come up

Old problems and solutions

1.the "Time difference": it is because of two thing

(1)the wait(ms) function to clear the task somehow make different delay times

(2)for the simulate signal to trigger the camera shouldn't put in the while loops

2.daq assistant can only have one ai and one ao

the new problem is:

how can I keep record  the data from daq assistant without stop recording when it triggering the camera(simulate signal) in the Dynamic Event Triggering

all I want is to record the data(keep recording for all time) but when the voltage reaches the specific value then it sends a signal to the camera(simulate signal)

please give me some advice,thanks a lot