Discussion:
one device aquires one triggers
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Beaton
2008-07-31 19:10:11 UTC
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Here is my problem
 
I have a NI-9234 using a NI USB-9162 sleeve. The NI-9234 does not support hardware triggering, and the software triggering does not meet my needs for timing. Is there a way to use my DAQCard 6062E to trigger in someway either the vi or the acquisition
 
 
Beaton
2008-07-31 19:40:08 UTC
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PS
I need to aquire with th NI 9234 because of noise issues with the DAQCard
samantham
2008-08-04 12:40:20 UTC
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Hello,
You mentioned that the software triggering does not meet your needs for triggering ... What are your needs?  Please provide a little more information about the application and how triggering is involved. 
You could very well have a VI look for a trigger on the 6062E and then use this status to route (in software) to the 9234 task.  However, this is like using an software trigger.  Would this work for you?
 
Beaton
2008-08-05 12:10:22 UTC
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Hi Sam

The problem I have with the software trigger is that I need my program to wait for the trigger pulse then to acquire a certain amount of samples a a certain rate to give me the record length of data that I need. The software trigger does not work for me because it first acquires the samples then analysis them for the trigger. If the trigger happens late in the samples acquired, the record length is too short. I tried to loop the program around to acquire more after the trigger has occurred but there is a gap in the samples acquired.
Thanks
Beaton
2008-08-05 19:10:18 UTC
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Hi
This is what I have tried, is there any simplier way that reduce the time delay between trigger and acquistion. I would like to have the trigger to be time zero of the data waveforms, or as close as possible
 
Thanks


Software_Trigger.vi:
http://forums.ni.com/attachments/ni/170/346826/1/Software_Trigger.vi
samantham
2008-08-11 14:10:10 UTC
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Hello,
I am assuming that you are using the example from the Example Finder titled Cont Acq&Graph Voltage - Analog Software Trigger.vi.  Please clarify if this is the example that you are unhappy about the samples relative to the trigger.  This type of software trigger is going to be the best solution of a trigger on the 9234.  If you believe that the examples is not grabbing all the post samples that you would like, please futher example the setup with how many pre and post samples are needed.
I do understand that you have a 6062E to hardware trigger from, however routing this trigger in software is also going to have some limitations.  The code you have attached is going to have delay between when the trigger happens ... the 6062E task will have to finish the read of 100 samples and then the error status will trigger the 9234 task.  I also wanted to note that the code posted in missing a sub vi needed to run.  I look forward to hearing back from you.
Beaton
2008-08-11 17:10:06 UTC
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Hi
Thanks for your reply. I should have posted that I have posted that I have solved my trigger issue by using seperate while loops for the continuous acq. and the software trigger and this eliminated my problem.
 

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