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Enable JPIN and JPOUT Function Group Behavior

Chris Litwin 5 months ago in IQANdesign updated by Gustav Widén (System support) 3 months ago 5

I'm experiencing, what I believe to be some, odd behavior while using function groups to enable/disable JPINs and JPOUTs in simulator. 

JPIN

When I  disable, then enable a function group containing JPINs they do not reactivate. It does not occur in the initial transition from disable to enable, but each time after that they do not come back online.

JPOUT

The JPOUTs in a disabled function group don't appear to ever be disabled. 

I have attached an example program.

ENABLE J1939 FXN GROUPS.idsx

Looking at your project file, the key is that at a minimum, the JFIN and JFOUT channels need to be located in the disabled function groups to accomplish what you want.

Ok, so you can't disable individual parameters without disabling the frames? And, is that how it would behave on a real system?

correct.  You'd have to define separate jfin / jfout with the relevant parameters that you want to enable and disable.

+1

Normally, the frames and parameters are in the same function group. 


The case with the frame channel in one function group and its corresponding parameters in different function groups that gets disabled works better in 6.02. 

But the function isn't fully supported; for example a JPOUT that is disabled will have error value 0, but the J1939 standard prescribes setting bits to 1 for parameters that aren't available. To implement this, a math channel with two states as input to the JPOUT would be the better way.