Method ITcCyclicCaller:AddModule

Reports the ITcCyclic interface of a module to a cyclic caller, e.g. a TwinCAT task.

Syntax

virtual HRESULT TCOMAPI
AddModule(STcCyclicEntry* pEntry, ITcCyclic* ipMod, ULONG_PTR
context=0, ULONG sortOrder=0)=0;

Parameter

pEntry: (type: STcCyclicEntry) [in] pointer to a list item that is inserted into the internal list of the cyclic caller; see also description.

ipMod: (type: ITcCyclic) [in] interface pointer used by the cyclic caller.

context: (type: ULONG_PTR) [optional] a context value that is transferred to the ITcCyclic::CyclicUpdate() method with each call.

sortOrder: (type: ULONG) [optional] the sorting order can be used for controlling the order of execution if various module instances are executed by the same cyclic caller.

Return value

If successful, S_OK ("0") or another positive value will be returned, cf. Return values. Extended messages refer in particular to the column HRESULT in ADS Return Codes.

The error ADSERR_DEVICE_INVALIDSTATE is returned if the cyclic caller, i.e. the TwinCAT task is not in the OP state.

Description

A TwinCAT module class normally uses a Smart Pointer to refer to the cyclic caller type ITcCyclicCallerPtr. The object ID of the task is stored in this Smart Pointer and a reference to the task can be obtained via the TwinCAT object server. In addition, the Smart Pointer class already contains a list item. Therefore the Smart Pointer can be used as the first parameter for the AddModule method.

The following sample code shows the login of the ITcCyclicCaller interface.

RESULT hr =
S_OK;
 
if ( m_spCyclicCaller.HasOID() ) {
 
 if ( SUCCEEDED_DBG(hr =
m_spSrv->TcQuerySmartObjectInterface(m_spCyclicCaller)) )
{
 
     if ( FAILED(hr =
m_spCyclicCaller->AddModule(m_spCyclicCaller,
THIS_CAST(ITcCyclic))) ) {
 
      m_spCyclicCaller = NULL;
 
     } 
 
 }
 
}