Trigger With 9205 Module

[DePeppers]

The aim of this community VI ( I've had help) is to record and log data off of channels that you preselect in the VI.  I have a 9223 module and a 9205 module paired to 9185 chassis. The only reason I am using the 9205 is for a trigger signal for the 9223 BNC.

My problem is, I'm a bad programmer, and I lack the knowledge to configure the trigger.  I have the 9205 in differential terminal configuration and the 9223 is setup that way by default.

Where am I missing the mark. 

Thanks to everyone that

has helped me to this point,  mcduff, Jay14159265, and altenbach.

[mcduff · Accepted solution]

You need to specify an analog trigger. The trigger Channel must be ON, that is, one of the AI inputs you specify in the beginning of the task along with setting the level and slope. The trigger should be a single channel, not multiple channels. 2020 version attached.

EDIT: You need to use a different trigger VI also, Start Analog Edge.

[mcduff]

One more thing, just played around with simulated instruments, 9205, 9223. You need to use a channel on the 9205 as the analog trigger, the 9223 does not support analog triggering.

But if you combine 9205 and 9223 channels in the same task you can use a channel in the 9205 as an analog trigger for both modules.

[DePeppers]

Thanks mcduff.  

What you are saying is (like in the daqmx code), I have to initialize the settings plus the operations.  What I need to do is create tasks for different tests we plan on running and I can leave the physical channel control if I need to just record the voltage.  All a task is a collection of preset calibrations, trigger, and sample options.  If I create the task and decide to have a control for sample rate does this cancel the trigger.

[mcduff]

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@DePeppers wrote:

Thanks mcduff.  

What you are saying is (like in the daqmx code), I have to initialize the settings plus the operations.  What I need to do is create tasks for different tests we plan on running and I can leave the physical channel control if I need to just record the voltage.  All a task is a collection of preset calibrations, trigger, and sample options.  If I create the task and decide to have a control for sample rate does this cancel the trigger.

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You can have a general task that you can use over and over for multiple situations. I have a program that does exactly that. Look in the example finder for DAQmx and see how NI does it.

This is what I am trying to say:

• If you want an analog trigger, then that channel needs to be active for the analog trigger. That is, in your data acquisition you analog trigger is recorded. This is not the case for a digital trigger.
• You can specify or change things before the task starts, like trigger level, sample rate, etc. Once the task starts, you cannot change these things without stopping and clearing the task.
• For your particular devices, 9223 and 9205. If you only acquire data from the 9223, then you CANNOT use an analog trigger; the 9223 does not support it. If you combine your 9223 acquisition with a channel from the 9205, you can use that channel in the 9205 as an analog trigger; it will then trigger the 9223. Reread the first bullet. The analog trigger channel from the 9205 must be on and configured in your task for this to work.

[DePeppers]

Awesome.  I was making this more difficult than it actually is.  I had a bnc coming off of the 9223 and a split bnc cable attached to the 9205 reading the same signal.  Like you are saying, it is simpler to use the 9205 to record the signal and as the trigger instead of separating the actions.

[mcduff]

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@DePeppers wrote:

Awesome.  I was making this more difficult than it actually is.  I had a bnc coming off of the 9223 and a split bnc cable attached to the 9205 reading the same signal.  Like you are saying, it is simpler to use the 9205 to record the signal and as the trigger instead of separating the actions.

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Not exactly as I did not know your complete problem. Maybe this is more clear, if you use an analog trigger, then that channel has to be in the analog input task configuration VI. For example, ai1 is the analog trigger. Then I must include ai1 in the physical channels for the AI Voltage configuration.

Glad it is working for you.