Query the digitizer about trigger status

[geraldW]

Hello,

I want to use the NI5112 digitizer. For some of my use cases it is only relevant if the digitizer has received a trigger signal or not. Is there a possibility to query the digitizer about the trigger status?

Kind regards,

Gerald

[Marco_Brauner]

Hi,

could please explain a little mor detailed what you mean and want to do?
For me, a trigger is configured for a specific action, i.e. an acquisition, and u can see that the trigger occured
when the action is executed. So I don´t  understand your question exactly...

regards

Marco B. NIG

[geraldW]

Hello,

I am want to test an electronic device with an automatic test system. For some of my tests, I need only the information if the device has set its trigger-output (which is connected to the digitizers trigger-input). Therefore, it would be enough information for me to find out if the oscilloscope has received the trigger signal or not.

Gerald

[Marco_Brauner]

Well,

I think there are basically two ways to check if the trigger occured:

1.)   measuring and monitoring the trigger signal it in parallel with a DIO-Line or Analog

2.)   just checking the Signal-Acquisition - if a trigger was configured and the Scope acquired a value, than the
       trigger has occured.

That are the possibilities in my opinion.


regards


Marco B. NIG

[Jeff_B.]

You should be able to configure your trigger for the 5112, initiate the acquisition, and then poll the acquisition status by calling "niScope Acquisition Status".  If the acquisition completes, your trigger was received.  You do not have to fetch any data in this case.

[DFGray]

If you acquisition would be long, you can also query the Fetch->Points Done attribute.  If it is over zero, the trigger occurred.  If your reference position is over 0% (it is 50% by default), then the first number over zero you get will be the full number of pretrigger points.

[MarcBAE]

I'm having a triggering/acquisition issue as well.

My digitizer is set up for triggered acquisitions. I initialize the acq then start polling the device using Acquisition_Status for a specified amount of time. Every now and then my loop times out (i.e. didn't get the IVISCOPE_VAL_ACQ_COMPLETE response from the function call). So I'm trying to determine if the problem is:

1. Unit did not receive the trigger.

2. Unit received the trigger but didn't have enough time to complete the acquisition.

3. Received the trigger but had some other problem.

It would be helpful if I could query the instrument to see if it did in fact receive a trigger signal which would help isolate the fault. I can't find anything in the NI_SCOPE documentation that indicates if this would work with a 5154 digitizer.

[Nathan-P]

The last post in this thread was in 2007, your question will get better visibility if you post your question as a new topic and link this thread.

To answer your question, if the fuction returns NISCOPE_VAL_ACQ_IN_PROGRESS, then that means that the trigger was recieved, but that the acquisition engine is still acquiring samples.  COMPLETE means that all the samples that have been requested have been acquired and are ready to send to the host.

You can also use the Attribute NISCOPE_ATTR_POINTS_DONE or NISCOPE_ATTR_BACKLOG to find out if the acquisition has begun (recieved reference trigger), the values will be greater than 0.

I hope this helps.

[MarcBAE]

Great - Thanks!

[MarcBAE]

"To answer your question, if the fuction returns NISCOPE_VAL_ACQ_IN_PROGRESS, then that means that the trigger was recieved"

Nathan, can you confirm this please? When I look at the header file 

#define NISCOPE_VAL_ACQ_COMPLETE IVISCOPE_VAL_ACQ_COMPLETE
#define NISCOPE_VAL_ACQ_IN_PROGRESS IVISCOPE_VAL_ACQ_IN_PROGRESS

ACQ_COMPLETE = 1

ACQ_IN_PROGRESS = 0

I seem to be getting the in progress message before the trigger is occurring and I'm wondering if the "in progress" message could mean that the instrument is also waiting for a trigger or rather, that the acquistion has been initiated but not completed.