FB_HandshakeHmi

Implements a general handshake procedure with life sign mechanism and companion identification.

	Class is abstract Since the class is defined as `ABSTRACT`, the class cannot be instantiated and must be implemented using inheritance.

Syntax:

FUNCTION_BLOCK ABSTRACT FB_HandshakeHmi EXTENDS FB_BaseHmi

Name	Type	Access	Initial value	Description	PLC / HMI¹
Reset	BOOL	Get, Set	FALSE	Request to reinitialize the communication.	HMI
FB_HandshakeHmi
CompanionID	UINT	Get, Set	0	ID of the currently connected HMI Companion.	HMI
LiveSignHMI	UINT	Get, Set	0	Changing value of the HMI client to signal an active connection.	HMI

¹The PLC/HMI column describes the assignment of the write access.

Name	Type	Access	Initial value	Description
Name	STRING	Get, Set	<SourceName>	Specifies the name of the class instance.
FB_HandshakeHmi
CompanionTimeout	LREAL	Get, Set	5.0	Time after which the Companion is considered disconnected (no longer connected) if there is no sign of life.
Disconnected	BOOL	Get	FALSE	The connection to the Companion has been lost.
FB_Base
BaseState	E_BaseState	Get	eNotHandled	Initialization state of the class instance.
Error	BOOL	Get	FALSE	Class is in an error state.
ResultMessage	I_AppMessage	Get	-	Access to the class-internal EventLogger.
[`PROTECTED`] _Name	STRING	Get	<SourceName>	`.Name` without leading 'fb'.

Name	Description
Reset()	Resets the error state of the class.
FB_HandshakeHmi
Cyclic()	Cycle method
FB_Base
GetHMI()	Returns the assigned HMI object. The method is not implemented in the FB_Base class. If the method is not overwritten by inheritance, a pseudo variable is always returned.
SetHMI(`ipBase`)	General assignment method for an `FB_BaseHmi` extending class as a local HMI. The method is not implemented in the FB_Base class. If the method is not overridden by inheritance, it always fails.
[`PROTECTED`] _IsMyself(`iCmp`)	Identifies whether the transferred object corresponds to its own instance.
[`PROTECTED`] _QueryNamespace()	Extracts the first part of the instance path as an object namespace.
[`PROTECTED`] _QueryObjectName()	Extracts the last part of the instance path as the object name.

Type	Description
I_Base	Standard interface on FB_Base.
I_HandshakeHmi	Standard interface on FB_HandshakeHmi
I_BaseDev	Covers all methods and properties of the base class.
I_Comparable	Enables comparisons via `_IsMyself()` or F_IsSameInstance().

Development environment	Target platform	PLC libraries to include
TwinCAT 4026 >= v3.1.4026.19 TwinCAT 4024 >= v3.1.4024.71	PC or CX (x64, x86)	Tc3_PlasticBaseApplication (>= v12.16.0.0)