Namespace PlcDocu.TcoCore

Classes

Describes the status of a step of the sequencer.

StringBuilder

Allows to concat strings using fluent interface. It's similar to C# StringBuilder class Usage as follows :

	ErrorString := _stringBuilder
		.Clear()
		.Append('Error number: ')
		.Append(INT_TO_STRING(ErrorNumber))
		.Append('. Message: ')
		.Append(ErrorMessage)
		.Append('.')
		.ToString();

Inspired by Gerhard Barteling blogpost at https://www.plccoder.com/fluent-code/

Root construction container, provides context information for TcoObjects declared within its scope. This function block is abstract and cannot be instantiated. Use Run() to run this context, Run method must be called only once per PLC Task cycle. Several 'TcoContext' instances can be declared and called inside one TwinCAT PlcTask, but only once per PLC cycle. The instance should not be accessed from several Twincat PlcTasks. Default implemenation of the 'TcoContext' allows its child members access properties StartCycleCount and EndCycleCount, messenger settings, rtc and other information related to the context of the running logic.

tip

A TcoContext can contain objects, components and PLC logic of one independent station of the machine, while the another one can cover the same for another station.

tip

TwinCAT PlcTask and TcoTask() refer to two different concepts.

TcoContextCompatibility

TcoContextEnvironment

TcoContextNfCompatibility

TcoDialog

Provides standard dialog to interact with the user.

TcoDialogBase

Base block for interactive dialogs.

TcoLogger

Default implementation of Logger.

tip

This type is partially extended by IVF to retrieve messages from the logger in IVF application.

TcoLogItem

Logger message object contains complete message details including time stamp, message text, message category, identity of the message provider, context cycle in which the message was posted.

TcoMessage

Complete message details including time stamp, message text, message category, identity of the message provider, context cycle in which the message was posted.

TcoMessageDigest

TcoMessenger

Provides mechanism for delivering static messages to the supervising applications (SCADA/HMI).

important

Each messenger has a single placeholder for the message; it stores the most important message from the last context cycle. If there are more messages in a single cycle for the same messenger then less important messages are discarded and replaced by the message with the category of higher severity.

important

Messenger can send the data to context logger. There is a maximum limit of 10 different messages per messenger in 2 consecutive context cycles. The messages that exceed this limit won't be logged when `OnEventRisen` logging is set. Take this behaviour into account when designing your system.

TcoMessengerEnv

TcoMomentaryTask

Provides basic momentary on function.

To get the actual state of the momentary task, , and State properties are available.

TcoObject

Basic construction block from which all blocks of a TcOpen application should derive in order to take advantage of the framework. This function block is abstract and must be implemented in a derived block. TcoObject, must be constructed via FB_init(ITcoObject) method at instantiation. TcoObjects that belong to same TcoContext share the same context. This is typically achieved by constructing the object with FB_init(THIS^), where THIS^ is of ITcoObject (note that ITcoContext also implements ITcoObject).

warning

Whenever it is required to pass function block parameters of a block type that derives from `TcoObject` it should be passed as **reference**. This means either via appropriate interface or as `REFERENCE TO` in VAR_INPUT and VAR_OUTPUT sections or as VAR_IN_OUT. Be aware the VAR_INPUT and VAR_OUTPUT create a copy of the variable.

Example

All the variables _myContext, _ContextTcoObjectA, _ContextTcoObjectB, _ContextChildTcoObject should have all the same value.

All the variables _myIdentity, _TcoObjectAidentity, _TcoObjectBidentity, _ChildTcoObjectidentity should have uniques values.

		//Definition of the myTcoObject 
		FUNCTION_BLOCK myTcoObject EXTENDS TcoObject
		VAR
			  _myChildTcoObject	:	myChildTcoObject(THIS^);
		END_VAR
		//Definition of the myTcoContext 
		FUNCTION_BLOCK myTcoContext EXTENDS TcoContext
		VAR
			  _myTcoObjectA		:	myTcoObject(THIS^);					
			  _myTcoObjectB		:	myTcoObject(_myTcoObjectA.Context); 
			  _myContext		:	ITcoContext;
			  _ContextTcoObjectA	:	ITcoContext;
			  _ContextTcoObjectB	:	ITcoContext;
			  _ContextChildTcoObject	:	ITcoContext;
			  _myIdentity		:	ULINT;
			  _TcoObjectAidentity	: 	ULINT;
			  _TcoObjectBidentity	: 	ULINT;
			  _ChildTcoObjectidentity	: 	ULINT;							
		END_VAR
		//Plc code of the myTcoContext 
		_myContext		:= 		THIS^.Context;
		_ContextTcoObjectA	:=		_myTcoObjectA.Context;
		_ContextTcoObjectB	:=		_myTcoObjectB.Context;
		_ContextChildTcoObject	:=		_myTcoObjectB._myChildTcoObject.Context;
		_myIdentity		:=		THIS^.Identity;
		_TcoObjectAidentity	:=		_myTcoObjectA.Identity;
		_TcoObjectBidentity	:=		_myTcoObjectB.Identity;
		_ChildTcoObjectidentity	:=		_myTcoObjectB._myChildTcoObject.Identity;

Explanation

The context of the myTcoContext instance is assigned to itself. As the _myTcoObjectA context is assigned to this instance of the myTcoContext, it is assigned to the same context, and the value of the _ContextTcoObjectA will be the same as the value of the _myContext.

The context of the _myTcoObjectB instance is assigned to the _myTcoObjectA, that has already assigned context to this instance of the myTcoContext. So the value of the _ContextTcoObjectB will be the same as the values of the _ContextTcoObjectA and _myContext.

The context of the _myTcoObjectB._myChildTcoObject instance is assigned to the _myTcoObjectB, that has already assigned context to _myTcoObjectA, that has already assigned its context to this instance of the myTcoContext. So the value of the _ContextChildTcoObject wile be the same as the values _ContextTcoObjectB,_ContextTcoObjectA and _myContext.

As the Identities of all objects points to the themselves, all identities will have different values, as all objects are unique.

TcoParentedStructure

TcoRemoteTask

Remote tasks delegates its execution to C#. When this task is invoked a C# method will be called. To initiliaze

RemoteTask

with C# method use the

Initiliaze

InitializeExclusively

method.

        partial void PexConstructor(IVortexObject parent, string readableTail, string symbolTail)
		{
			_remoteTaskInstance.InitializeExclusively(Create);  			
			//_remoteTaskInstance.Initialize(Create);           
		}
		private bool Create()
		{
			//your code.
			return true;
		}

TcoRtc

TcoSequence

TcoSequencer

TcoSequencerBase

Provides basic sequential control, including step mode, which allows to run the sequence step-by-step, steping forward and steping backward.

TcoSequencerModeController

Provides switching between sequencer modes so as handling stepping tasks in the step mode.

TcoSequencerObserver

TcoSignalInfo

Provides symbol information about a I/O signal.

important

`SymbolPath` can only contain string of 255 characters.

tip

This block is partially extended by IVF to provide more information about the symbol.

TcoState

TcoStateBase

Provides basic state controller. It could be implemented using IF, IF ELSIF or CASE statement. The transition to the different state needs to be perfromed by calling method. This method ensures also calling the OnStateChange(Object, Object) every time that state is changed. The OnStateChange()could be overloaded and some custom code that needs to be executed on each change of the state could be placed here. The TcoState could be used like this:

Example 1

_myTask() is not a member of this TcoState(), it is restored manually to be able to trigger it in the next state.

	IF State = 10 THEN
		Main._myTask.Invoke();
		Main._myTask.Execute();
		IF Main._myTask.Done THEN
			ChangeState(State + 10);
			Main._myTask.Restore();
		END_IF
	END_IF
	IF State = 20 THEN
		Main._myTask.Invoke();
		Main._myTask.Execute();
		IF Main._myTask.Done THEN
			ChangeState(State + 10);
			Main._myTask.Restore();
		END_IF
	END_IF

Example 2

_myTask() is a member of this TcoState(), it is restored manually using the fluent syntax to be able to trigger it in the next state.

	CASE State OF
		10:	
		_myTask.Invoke();
		_myTask.Execute();
		IF _myTask.Done THEN
			ChangeState(State + 10).RestoreObject(_myTask);
		END_IF
		20:
		_myTask.Invoke();
		_myTask.Execute();
		IF _myTask.Done THEN
			ChangeState(State + 10).RestoreObject(_myTask);
		END_IF	
	END_CASE

See for more details.

TcoStateExtendible

TcoStruct

Basic structure block from which most of the structures in TcOpen derive. TcoStruct provides construction mechanism to allow for access to the parent function block and the context.

important

The derived structure must be initialized in the declaration of the function block `mystruct : MyCustomStructure := (Parent := THIS^)`, when nested in another structure `mystruct : MyCustomStructure := (Parent := THISSTRUCT)`. This will provide access to the `TcoContext` and parent `TcoObject`.