MEMCPY

MEMCPY 1:

The function MEMCPY can be used to copy the values of PLC variables from one memory area to another.

FUNCTION MEMCPY : UDINT

VAR_INPUT
    destAddr      : UDINT;
    srcAddr       : UDINT;
    n             : UDINT;
END_VAR

destAddr: start address of the target memory area.

srcAddr: start address of the source memory area.

n: number of bytes to be copied.

The function copies n bytes from the memory area that starts at srcAddr to the memory area that starts at destAddr.

Return parameter	Meaning
0	Incorrect parameter values. destAddr == 0 or srcAddr==0 or n == 0
> 0	If successful, the number of bytes copied (n).

Example of a call in FBD

VAR
    Buffer1    : ARRAY[0..3] OF BYTE;
    Buffer2    : ARRAY[0..3] OF BYTE;
    CpyResult  : UDINT;
END_VAR

MEMCPY 2:

In the example, 4 bytes are copied from Buffer2 to Buffer1.