differences in DAQmx Trigger (VI)

[faustina]

I am trying to figure out why DAQmx Trigger VI works differently with different hardware.

Case 1; using PXI-6133 and Reference Analog Edge version of VI

Case 2; using PXIe-6368 and Reference Digital Edge version of VI

My users have shown me that using an analog signal on an analog channel for a trigger source in both cases works.  Now, using the same trigger source conditions, I want to use a PXI-6133 and Reference Digital Edge version of VI.  This does not work.  Why?

My goal is to create a subVI that will use the appropriate DAQmx Trigger VI, given the source trigger hardware.  My application will aquire 2 sets of data simultaneously on different hardware.  One set based on a trigger, one set continueuosly.  Does this seem unreasonable? 

[Petru.T]

Hi faustina, 

I had a look into your problem but I just need to clarify your problem a bit. From what I understood you have used an analog signal on an analog channel as a trigger on both PXI cards and that worked. Now, if I understood corectly, you are trying to use the same analog signal on an analog channel on the 6133 card but now using the DAQmx Trigger VI in Reference > Digital Edge mode and this doesn't work. Did an analog signal on an analog channel worked as a trigger with your 6368 card when the DAQmx Trigger VI was set to Reference > Digital Edge? Also, could you please specify what type of PXI chassis you are using? Also, it would be useful if you could upload your VI here so that I can understand better what you are trying to do. 

[faustina]

Case 1; using PXI-6133 card in PXI-1045 chassis
DAQmx Trigger VI in Reference Analog Edge mode
inputs
 - task in [programmatically built by application*]
 - source ['Trigger' of string data type, name corresponds to HScard#/ai#]
 - edge [user selected in application]
 - error in
 - pretrigger samples per channel [computed by application]

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Case 2; using PXIe-6368 card in PXIe-1075 chassis
DAQmx Trigger VI in Reference Digital Edge mode
inputs:
 - task in [programmatically built by application*]
 - source ['HScard#/PFI0' of IO name data type, according to users only valid input]
 - edge [user selected in application]
 - error in
 - pretrigger samples per channel [computed by application]

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

new Case; using PXI-6133 card in PXI-1045 chassis
DAQmx Trigger VI in Reference Digital Edge mode
inputs:
 - task in [programmatically built by application*]
 - source [of IO name data type]
 - edge [user selected in application]
 - error in
 - pretrigger samples per channel [computed by application]

Error is generated at DAQmx Start Task VI prior calling DAQmx Read VI in Analog 1D Wfm NChan NSamp mode.

* Task is programmatically created based on collection of channels per device.  Channel parameters are specified in spreadsheet file created by users.  The application processing the file to create channels (using DAQmx Create Virtual Channel VI) and tasks.

[faustina]

TrigConfig.png - code from main VI that create parameters for Trigger

Setup Triggers.vi - subVI that configures Trigger

Kevins_Triggered Fast DAQ.vi - working VI for PXI-6133 and PXI1045

[faustina]

workingVI inputs.pptx - inputs for working VI with PXI-6133 and PXI-1045

Analog- Finite Input.vi - VI used to test code, borrowed from example Digital-Finite Input.vi

[faustina]

lost last attachment

[Petru.T]

Hey faustina,

I had a look at your new, clarified problem description and VIs.

I see that in case 1, you used the trigger VI in the Reference Analog Edge mode with an AI trigger source whereas in case 2 you used the same VI in the Reference Digital Edge mode with a digital PFI0 trigger source. Therefore, can I just suggest that you make sure that in your new Case you are using a digital line as your trigger source? 

[faustina]

have done so.  Analog signal to an analog line in case 1 works.  Analog signal to a digital line in case 2 works.  Trying to repeat analog signal to a digital line for new case.

[AB@17]

It seems every thing ok with your code can you post the code with values you are giving input

[faustina]

If you run Analog-Finite.vi and specify any analog channel and use Reference Analog Edge mode, I get error -200284 for my hardware for any timeout (except -1) for my new hardware configuration.