FB_init

Short Summary

The constructor FB_init is needed to create an unique hash code. The hash code is a pseudo random number create with a xorshift_ algorithm. It can be overwritten on derivations, because it will be called implicit, SUPER^.FB_init() is not required. For more information check: Behavoir with derived function blocks_

.. _Behavoir with derived function blocks: https://infosys.beckhoff.com/content/1033/tc3_plc_intro/5482088715.html?id=6983869892358031022 .. _xorshift: https://en.wikipedia.org/wiki/Xorshift

parameters

• Return type: BOOL

Parameters

Name	Type	Comment	Kind
bInitRetains	BOOL	if TRUE, the retain variables are initialized (warm start / cold start)	input
bInCopyCode	BOOL	if TRUE, the instance afterwards gets moved into the copy code (online change)	input
rootNode	INodeApi	first node, e.g. Workflow or Station (can be 0)	input
safety	CNM_OpModeHandlingInterfaces.ISafetyReleaseDistributor	safety to subscribe	input

Code

Declaration

METHOD FB_init : BOOL
VAR_INPUT
	(* if TRUE, the retain variables are initialized (warm start / cold start)*)
	bInitRetains	: BOOL;
	(* if TRUE, the instance afterwards gets moved into the copy code (online change) *)
	bInCopyCode	: BOOL;
	(* first node, e.g. Workflow or Station (can be 0) *)
	rootNode :INodeApi := 0;
	(* safety to subscribe *)
	safety :CNM_OpModeHandlingInterfaces.ISafetyReleaseDistributor;
END_VAR

Implementation

IF ( THIS^.isObjectValid( rootNode ) ) THEN
	THIS^.root := rootNode;
ELSE
	THIS^.root := 0;
END_IF
IF THIS^.isObjectValid(safety) THEN
	safety.subscribe(THIS^);
END_IF