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MEMORY_COPY

Type	Function
Description	Copies data from one runtime system data area (source data area) to another runtime system data area (destination data area).
Notes	For this type of data management it is recommended to use the data types STRUCT and ARRAY. The function may only be useful for special data operations that are carried out performantly as copying is done synchronously with the task.
Parameters	Inputs SRC Data type: ANY Description: Variable of the source data area. Note Specifying an array element such as MyArray[5] is permitted but this references a single array element and not the start element for the entire area. SRC_OFF Data type: ANY_INT Description: Offset in bytes related to the beginning of the source data area. The value must be greater than or equal to zero. DST Data type: ANY Description: Variable of the destination data area. Note Specifying an array element such as MyArray[5] is permitted but this references a single array element and not the start element for the entire area. DST_OFF Data type: ANY_INT Description: Offset in bytes related to the beginning of the destination data area. The value must be greater than or equal to zero. CNT Data type: ANY_INT Description: Number of bytes to be copied. The value must be greater than or equal to zero. Output OUT Data type: UINT Description: Status of the copy process. 0 The copy process has been finished correctly. 1 The VAR_IN_OUT descriptors used for the parameters SRC and DST are invalid. This is an internal error. 2 The length of the source buffer or the value of SRC_OFF does not fit. The size of bytes to be copied assigned in CNT is larger than the available size of SRC - SRC_OFF. SRC_OFF must be >= 0. 3 The length of the destination buffer or the value of DST_OFF does not fit. The sum of the bytes to be copied assigned in CNT and the offset in the connected byte stream assigned in DST is larger than the size of the connected byte stream. DST_OFF must be >= 0. 12 Value of CNT not in range.
Error behavior	Error behavior The following table shows the errors which may occur while executing the function and the value returned by the function in the corresponding error case. Error case Output value OUT != 0 Error code
Additional information	EN/ENO behavior The POU is only executed if TRUE is applied to the EN input. If EN = FALSE, the POU is not executed and ENO = FALSE indicates the inactivity. If any of the errors listed under "Error behavior" occurs while executing the function, ENO is set to FALSE. Further Info See the topic "General information on execution control with EN/ENO" for further details.
Example	Example in ST Data type declaration:    TYPE       MyArray : ARRAY[0..7] OF BYTE;    END_TYPE 'Variables' table with declarations: Code in ST: Out := MEMORY_COPY(MyVar_SRC, MyVar_SRCOFF, MyVar_DST, MyVar_DSTOFF, MyVar_CNT);