How to use Start_ code block in AC800M ?and how to find it?

Hi,
I need to detect first start cycle of application,e.g. Enable logic just in one Cycle after warm restart,
I checked "FirstScanAfterApplicationStart" function, but it acts after Download the changed Application,
the Start_ code block is other way mentioned in on of posts,as below:
https://forum-controlsystems.abb.com/...
but i cannot find it in AC800m CBM, Where is it?
Thanks for Help

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aminjalili Rank: 971

Asked 4 months ago

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You just make a code block and call it "Start_Something"

Note that this ONLY works in Control Modules - NOT POU Programs. In this case you can use "FirstScanAfterApplicationStart" or "FirstScanAfterWarmStart"

or you can just code code a very simple workaround ...

Define "FirstScan" as Local Variable, type = Bool, Retain = Blank (ie not retained), Initial Value = TRUE

```
IF FirstScan THEN
FirstScan:=FALSE;

// Your Initialization Code Goes Here

END_IF;
```

Every time the controller is downloaded (warmstarted) "FirstScan" will be set to "TRUE" ( This initital value is not retained ) Your Initialization Code will then execute once only.

You can adapt the same trick for Cold Restarts by setting FirstScan to "Retain" ( ie a Cold Start will reset the variable )