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U2702A IVI driver Getting the Acquisition Status

Question asked by jcuzens on Jan 20, 2009
Latest reply on Jan 22, 2009 by yongschew
Hi,

I am writing an application wherein I need to acquire data from a robotic system. I have been successful in implementing most of the application except the initiating and waiting on the acquisition. Largely, this is how my application works:

1.) Initialize
2.) Query Serial Number & Model
3.) Set the system up for Error Queries
4.) Set the trigger delay (0.0s)
5.) Enable Channel 1 disable Channel 2
6.) Set Offset (0.044V)
7.) Set Range (0.1V)
8.) Set Coupling (DC)
9.) Set Attenuation (1.0)
10.) Set Trigger Coupling (DC)
11.) Configure Trigger (Source = "EXT", Level = 7.93V, Slope = Positive)
12.) Set Holdoff (0.0s)
13.) Set Trigger Modifier (None)
14.) ConfigureRecord (Time Per Record = 3.2e-005s, Delay = 0.0s)
15.) Set Acquisition Type (Normal)
16.) Set Measurement Interpolation (None)
17.) Initiate Acquisition
18.) Check Measurement Status

Now, despite the fact that I don't get any errors from the driver or COM, and I don't have anything attached to my external trigger, I always get a Trigger Complete status when I check the measurement! Then, when I go to fetch the waveform I get a COM error because I know I never acquired any data!

Any ideas why this is happening? Is there some step I forgot?

Also, I can't seem to set a trigger delay that is very long when using a high sample rate??? If I sample at 1ns, then the max delay I can use is only 5ns! Why can't the delay be something big like 40uS? I really want to wait 40uS after a trigger pulse and collect 16000 data points sampling at 1 or 2nS but the card won't allow this!

Sorry that is a lot to go over but I appreciate any help!
Justin  

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