SysCpuCallIecFuncWithParams (FUN)

FUNCTION SysCpuCallIecFuncWithParams : RTS_IEC_RESULT

Call an IEC function from plain C code. Since different CPU’s/systems use different calling conventions, this function should be used as a wrapper. IEC functions or methods of function block use all the same calling convention: They have no return value and exactly one parameter, which is a pointer to a struct that contains all required IN and OUT parameters.

NOTE: A call to the function SysCpuCallIecFuncWithParams with the parameter values <pointer (not equal to NULL)> in pParam and <0> in iSize has the same result as a call with the parameter values <NULL pointer> in pParam and <0> in iSize. Both result in a call without parameters of the function passed in parameter pfIECFunc.

IN GENERAL: An IEC function must always be called with the parameters according to its definition. If an IEC function is called with parameters which do not correspond to the definition of the IEC function, the CODESYS Control runtime system may CRASH.

RETURN: Returns the runtime system error code (see CmpErrors.library) <SIL2/>

InOut:

Scope	Name	Type	Comment
Return	SysCpuCallIecFuncWithParams	RTS_IEC_RESULT
Input	pfIECFunc	POINTER TO BYTE	Pointer to the IEC function that should be called
	pParam	POINTER TO BYTE	Pointer to the parameter struct that contains the function parameters. Can be 0 if not used.
	ulSize	UDINT	Size of the parameter structure to copy the content on stack. Can be 0.