PXI-6133 Reference Analog Multi Edge Triggering

[aweesner]

I am new to LabVIEW, and so am trying my best to figure it out but I am having trouble. I am using the NI PXI-6133 S series device.

I have two AI Voltage channels and I need to trigger both channels, with pre- and post- trigger samples for both, whenever either one meets its individual trigger condition. I have successfully been able to trigger both channels with just one as the trigger source, but ultimately I need to be able to use all of the channels as trigger sources.

It seems like I should be able to do this with Reference Analog Multi Edge Triggering, according to the DAQmx 19.0 Manual: "[...] you can configure multiple channel sources acquiring in the same task to each have their own analog trigger condition. When any of the multiple channel sources satisfy their respective condition, a trigger is generated and the device will perform the specified action associated with the trigger." But when I tried this (vi attached) I got the following error: 

-200077 at DAQmx Reference Trigger (Analog Multi Edge).vi: 

Possible reasons: Requested value is not a supported value for this property. The property value may be invalid because it conflicts with another property. 

Property: Ref.TrigType

Requested Value: Analog Multi Edge

Possible Values: Analog Edge, Analog Window, Digital Edge, none

Additionally, I read here (https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z0000004A09SAE&l=en-US) that an AI channel cannot be used as the reference trigger source when you need pre-trigger samples for multiple channels, which is what I need to do. It says that the PFI  needs to be used as the trigger source instead. But that is only for E series devices, whereas I am using an S series device. I read something similar here (http://www.ni.com/documentation/en/ni-daqmx/latest/devconsid/anltrigeseries/), which also says that with more than one channel being used for the reference trigger the PFI needs to be used instead of AI, but again, this is in reference to E series devices. 

So, I am not sure if I need to change something in my vi in order to get the Multi Edge triggering working, or if I need to use the PFI rather than just the analog inputs, or if there is a completely different way to achieve this. I have been trying to work this out for a few days now but I am a bit lost at this point. Any help would be greatly appreciated.

--Alex

[BrinkHombre]

Hello aweesner,

Great research. You seem to be looking into some good resources. Could you clarify what your end application is?

• Start acquisition on every channel after any channel is triggered?
• Start acquisition for an individual channel based on a unique trigger for each channel?

Secondly, I noticed your edge configurations array of clusters (pink wire) is set at index 2. The first two elements in the array (0-1), have no channel name specified.

1. Is there a reason you are specifying two "blank" elements as edge configurations when only 2 channels exist in the task?
2. If you remove those first two elements, so that only the edge configurations for Voltage_0 and Voltage_1 are included, does the error go away?

Best regards,

[aweesner]

Hi Ryan,

What I ultimately need to do is start acquisition on every channel after any channel is triggered. 

That is a great question. I don’t think I fully understood what that part of the edge configurations is actually doing. I set it at two thinking that it represented the number of elements in the array, so two elements in the array for each the two channels. There is no reason for having the two blank edge configurations because I didn’t realize they were there. I will have to try getting rid of those when I can get back to my project on Monday to see if that changes anything. 

Thanks,

Alex

[aweesner]

Unfortunately I still get the same error as before after fixing the edge configurations. It seems that I just can't set the Reference Trigger type to Analog Multi Edge, which is disheartening as the multi edge triggering does exactly what I need my VI to do. I don't know what the reason is for it to not be working, and I am having trouble finding examples online that use this type of triggering. 

--Alex

[BrinkHombre]

Hello aweesner,

Thanks for the clarity. This is odd because the PXI-6133 supports the Analog Multi Edge triggering, according to the DAQmx C Reference help.

Have you seen this help documentation yet, Analog Triggering Considerations for C Series, E Series, M Series, and S Series Devices?

Can you replicate the error if both of the edge configuration settings are identical?

Can you replicate the error if you use only one of the Analog Multi Edge trigger subVI's at a time?

[aweesner]

Hi again Ryan,

Yes, I have seen that help page; in fact I linked it in my original post. That is where I saw that for E series devices the PFI's must be used as the trigger source, but apparently not for the PXI-6133. It does give a lot of good information but ultimately doesn't help me figure out why the multi edge triggering isn't working. 

And yes, I get the same error when I make both edge configurations identical. I am not sure exactly what you mean by "using only one of the Analog Multi Edge Trigger subVI's at a time," but if I create and configure only one edge configuration for one channel I also get the same error.

If I use two separate Start Analog Edge triggers before the Reference Analog Multi Edge Trigger, then the error occurs at the Reference Trigger. If I instead use the Start Analog Multi Edge Trigger as my start trigger rather than two separate start triggers then I get the same error, but it now occurs at the Start Trigger rather than the Reference Trigger (shown in image).

--Alex

[Mark_Gamble]

Did you ever get a sastisfactory solution/answer to this problem. I am getting exactly the same error and have the same requirement.

[aweesner]

Hi Mark,

Unfortunately I was never able to get the Analog Multi-Edge Triggering to work with my device. For my last project I had to settle and use a single trigger source in my VI. In future variations of the same project I will need the Analog Multi-Edge Triggering to work but I have yet to find the solution. 

[ja_austin]

Hi Aweesner,

I have been looking over the forums and came across your post about the Analog Multi Edge Triggering. I have the same DAQ card as you and we are also looking at capturing a trigger on multiple channels.

Looking at your previous messages with other users, and the code snippets you have put up, it seems we have come to the same code setup without any guidance from NI.

Have you managed to find a solution?

A previous user mentioned that the Analog Multi Edge Triggering was in the properties for the PXI 6133 in the following link http://zone.ni.com/reference/en-XX/help/370471AM-01/cdaqmxsupp/pxi-6133/ 

However I cannot see any reference to Analog Multi Edge Triggering, was this in originally when you checked but potentially has since been removed by NI?

[ja_austin]

Hi everyone,

Following on from my message yesterday, I have since spoken to NI and have been given confirmation that the 6133 cannot utilise the multi channel triggering. I have been told the card does not have an updated firmware that would allow this. 

NI recommend either doing the trigger check yourself instead of getting the DAQmx drivers to do this, this would be very heavy especially if you are capturing at very high rates.

Or to go with a card that has FPGA functionality built in such as the PXIe 7858. I am still in contact with NI and will look to post an outcome once I have one.

Thanks,

Jason