Function Decomposition

I am trying to decompose an Actor Function in the SA phase (see attachment). I have to add one more function called ‘Turn OFF’. However, the tool does not allow me to do so.
I was able to add 3 leaf functions before but cannot add any now. Why is that so? Is this against the rules? If yes, what is the best practice?

The Actor Function too of the palette is actually a shortcut. It created a Function AND an Actor, and allocated the Function to the Actor.
In your case, you need to

  • simply create a System Function inside “Control ACC” (“Control ACC” might temporarily become green because at that point all of its subfunctions are not allocated to Actors)
  • and then allocate it to the same Actor that is in charge of the “set desired distance”, “set desired speed”, etc.

Hi Stephane,
Thanks for the reply.
I tried creating a System Function in the ‘Control ACC’ function and it did not allow me to create that as well. Initially, I had created the ‘Control ACC’ Activity allocated to an Operational Actor and transitioned it. So I am now trying to decompose it in a SDFB. What might be the problem?

There is a strong Arcadia rule stating that “only leaf functions can be allocated”.
So, as your ‘Control ACC’ function is already allocated, the tool tries to prevent you from creating an error!
If you want to decompose your function, you should first deallocate it.
To do this, simply double-click on the Actor to whom it is allocated (go to the Semantic Browser to know it) and remove it in the “Allocated Functions” field.
Then you will be able to create subfunctions inside …

Hi Pascal,
Thanks for the response. It worked this time.