trigger on CAN multiplexed signal

[Madottati]

I want to Trigger on a specific Signal in a multiplex Frame. The help says:

To define a trigger signal for a multiplexed signal, use the signal name :trigger:.<frame name>.<signal name>. This signal returns 1.0 only if a frame with appropriate set multiplexer bit has been received since the last Read or Start.

Well, I do it as it is written above, but sometimes I get a 1 for the Trigger Signal, but 0 for the Signal of interest. The value of the Signal of interest is not 0. Sometimes I get the right value, i.e. 16. How to set up the Trigger Signal?

Madottati

[JefeL]

I made a quick test case and it looks like the trigger signal isn't resetting to zero after a new frame is received. Is this the behavior you are seeing or is your scenario different?

[Madottati]

Hi Jeff,

well in my opinion it is not an issue, when the Trigger value stays 1 once the Signal received a single time. For me that is not a Problem.

The Problem is that the Trigger in my case is set to 1, whereas the Signal not yet received. A Frame is received, but the Signal of my interest should come later along another MUX index.

To be more concrete, I want to receive the Signal value of "ad_ai_at1" from the attached database. The corresponding MUX value is 0x0F, but the Trigger Signal seems to be set also when the MUX value is 0x0B --> in this case is the value of "ad_ai_at1" = 0.

[JefeL]

Spent some time modifying my test case but was unable to reproduce the issue as described. Using the database provided, I transmitted multiple frames testing various mode values. In each test case, the trigger signal for the target mode value remained zero as expected. It was only after receiving the specified mode value dd the trigger signal switch to one and stay there.

I'm testing with XNET 17.5 on my end. What version are you using? 

[Madottati]

Hi Jeff,

I use XNET 17.0.1. I will give a try with 17.5.

[Hooovahh]

It is a snippet, go to the image at this address, then drag it to a folder in windows (saving it) then drag from that location to the LabVIEW block diagram to open it.  That being said the code was also attached as a zip.

[bodypillow]

Sorry to bump this super old thread, but can someone tell me exactly logistically how you might programmatically create these trigger signals in an application?  The only way I can get it to happen is by literally manually typing into the XNET signal constant box.  If I try to use the create XNET object (signal), it complains about the syntax.  Furthermore, even if I try to read the name of the trigger signal I created (which works by the way), the property node gives me an error about the syntax! Such a weird backdoor operation to be typing it in manually.

[Hooovahh]

These are just the string data type with some extra features.  I think all of the XNet IO data types can be replicated with a string constant, or string parsing and concatenating functions.  Also you can wire any of these XNet datatypes to a string indicator and see what the string equivalent is.