Cant call a STL written add-on instruction from an SFC main program

[Radu Babau 0]

Hello folks,

 

I am a rookie, self-training in PLC programming.

I have written an SFC exercise (attached ACD file). I also try to call STL written subroutines and add-on instructions, from within the SFC main program.

Calling the created subroutine works fine, but calling the add-on instruction fails from a reason which is above my level. I tried, tried and tried different solutions, with no avail. I am either wrong in writing the add-on (perhaps some missing but missing tag ?), or wrong is calling it.

Can someone please give me a hint on what I do wrong ?

 

Thank you, Radu

PS . I use Studio 5000 v24, combined with RSLogix 5000 Emulator.

 

 

SFC_trial.ACD

[Michael Lloyd 85]

I don't use SFC's. I see the usefulness but not in the things I do. However, I found this online-

To use a subroutine to control a transition, include an End Of Transition (EOT) instruction in the subroutine.

The EOT instruction returns the state of the conditions to the transition.

[Radu Babau 0]

Hello Michael,

Thank you for the quick reply & suggestion, I tried it, with no luck.

Also note that I am having problems with calling the add-on  instruction in my ACD (left-hand path), and not the subroutine (right-hand path). The add-on instructions manual 1756-PM010I, page 31, lists EOT, IOT, RET, etc., as "unavailable instructions", so I guess this is a dead end.

Still digging.

Radu

[Radu Babau 0]

Hello Michael,

I solved it, after learning the following add-on instruction specifics:

-  once you create a complete (Parameters and Local Tags  + Logic: see the rules in the above mentioned manual) add-on instruction (compiled successfully) with a certain name (say MUFFIN), you will observe that a new type of data (named MUFFIN) shows up under DATA TYPES, ADD-ON-DEFINED DATA;

- you now have to define (under Main Task /Programs PARAMETER AND LOCAL TAGS, or in the upper CONTROLLER TAGS) a new reference  tag (say PONNY) of this new MUFFIN type;

- now the set is on for a successfull call of the created add-on instruction: MUFFIN(PONNY, MUFFIN_IN, MUFFIN_OUT).

It is perhaps my rookie impression, after reading the manuals very carefully, that this sequence if NOT explained. 

Thank you again.

Radu

PS. Corrected ACD file attached.

SFC_trial_corrected.ACD