PXI

cancel
Showing results for 
Search instead for 
Did you mean: 

mapping of triggers on PXI chassis

I have several modules in a PXI-1042 chassis that I am tring to route the same trigger to [on the PXI-Trig0 line].  I am using the VISA Map Trigger VI, but I cannot seem to get it to work without error.  I am trying to use the front panel trigger from the PXI-8501 module [resource name PXI11::13::INSTR] as the souce and the PXI-Trig0 as the destination.
 
Since the VISA Map Trigger does not accept VISA sessions of class INSTR, how do you map a trigger from an instrument to the backplane?
 
Thanks.
 
Chris
0 Kudos
Message 1 of 5
(3,763 Views)

Hi Chris,

I think you will need to change the VISA class to the PXI backplane.  I recommend taking a look at the KnowledgeBase article on Programmatically Routing PXI Trigger Lines.  It does a really good job explaining how to route trigger lines in both LabVIEW and text-based code.

What is the specific error you are receiving?

Regards,

Lauren

Applications Engineering
National Instruments
0 Kudos
Message 2 of 5
(3,755 Views)

Lauren

Thanks for your reply.  I had looked at that example that you mentioned before I made this post and, although it provided some good information, it did not point me to the solution to my problem.  I want to route the trigger from the front panel of an instrument in the PXI chassis to the PXI backplane, not just from one trigger line to another on the backplane.  I did quite a bit of searching and could not find any examples relating to this particular situation.

For me, it doesn't make sense to change the VISA class to PXI backplane, because the trigger source [an instrument front panel] is not on the backplane.  The trigger destination [PXI_Trig0] is, but not the source.  If I use the instrument class and an instrument as the resource I get an error telling me that instrument class cannot be used.  So, even though the documentation on this function seems to indicate that it can be used to route a trigger in the way that I want, there seems to be no way to actually do it using this function.

I spent quite a bit of time searching the Labview help files yesterday and it seems to me that the solution to my problem is going to be to use DAQmx Connect Terminal.  I did not try this intially because it did not come up in the searches that I did on the NI website, Google or in the LabView help files.  The only thing that I was pointed to was the VISA Map Trigger.

I am curious as to why there is not a comprehensive listing of DAQmx functions that can be referenced?  It would have made finding the solution to my problem much easier.

 

Chris Bowers

0 Kudos
Message 3 of 5
(3,747 Views)

Okay, I have tried to use the DAQmx Connect Terminal function and it is still not accomplishing what I want.

As I mentioned in my initial post, I have a PXI-1042 chassis with five modules; a PXI-8105 Embedded Controller, a PXI-6232 Multifunction DAQ, two PXI-4220 Two Channel Bridge Input Strain Gauge Modules, and a PXI-4110 Programmable DC Power Supply.  I want to trigger the analog output and input of the Multifunction DAQ, and well as the analog input of the two Strain Gauge Modules all off of the same trigger.

Question 1:  When I use the DAQmx Connect Terminal function, I can select terminals of the multifunction DAQ or the two strain gauge modules as trigger sources/destinations, but the front panel trigger of the embedded controller does not seem to be available to me.  Why is this.

Question 2:  I can trigger a strain gauge module off of its front panel trigger without any problem but, when I route its front panel trigger to PXI_Trig0 using DAQmx Connect Terminal [Source Trigger = /Dev1/PFI0 & Destination Trigger = /Dev1/PXI_Trig0] and set things up to trigger off of PXI_Trig0 the module will not trigger.  Why is this?

Question 3:  I also cannot get the module to trigger if I route the front panel trigger of the second strain gauge module to PXI_Trig0 [DAQmx Connect Trigger w/Source Trigger = /Dev2/PFI0 & Destination Trigger = /Dev2/PXI_Trig0.  Why is this?

Is there a quicker way to get some response off of these discussion forums?  I made my initial post yesterday, just before lunch my time, but did not see any reply until this morning.  I replied to that posting as soon as I saw it, but I have not gotten any reply to that yet.  At this rate, it willl take me a week to get just this one problem resolved [maybe].  i appreciate the help, but there has to be a quicker way to get this done.

0 Kudos
Message 4 of 5
(3,741 Views)

This customer has contacted National Instruments for support and I will post back with an update when the issue is resolved.

Mallori M.

Mallori M
National Instruments
Sr Product Manager, Customer Proficiency

ni.com/training
0 Kudos
Message 5 of 5
(3,713 Views)