MEMMOVE
Use the MEMMOVE function to copy values from one memory area to another; the memory areas may overlap.
Notice | |
System crash or access to unauthorized memory areas Since the function directly accesses the physical memory, special care must be taken when using it. Incorrect parameter values can result in a system crash, or in access to forbidden memory areas. |
FUNCTION MEMMOVE : UDINT
Inputs
VAR_INPUT
destAddr : PVOID;
srcAddr : PVOID;
n : UDINT;
END_VAR
Name | Type | Description |
|---|---|---|
destAddr | PVOID | Start address of the destination memory area. |
srcAddr | PVOID | Start address of the source memory area. |
n | UDINT | Number of bytes to be copied. |
The function copies n bytes from the memory area with the start address srcAddr to the memory area with the start address 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:
PROGRAM MAIN
VAR
Buffer1 : ARRAY[0..3] OF BYTE;
Buffer2 : ARRAY[0..3] OF BYTE;
MoveResult : UDINT;
END_VAR
In the example, 4 bytes are moved from Buffer2 to Buffer1.
Requirements
|
Development environment |
Target system type |
PLC libraries to include (Category group) |
|---|---|---|
|
TwinCAT v3.1.0 |
PC or CX (x86, x64, ARM) |
Tc2_System (System) |