`SysCpuAtomicCompareAndSwap` (FUN)

FUNCTION SysCpuAtomicCompareAndSwap : RTS_IEC_RESULT

<description> Function for compare-and-swap in one atomic operation (task safe). Supports only 32- and 64-bit types

The function compares the pAddress value with the pCompareValue value. If the pAddress value is equal to the pCompareValue value, the pSwapValue value is stored in the address specified by pAddress. Otherwise, no operation is performed.

The function was successful if the *pSwapValue value is stored in the address specified by pAddress. </description> <result><p>RESULT: Returns ERR_OK if the swap was successful (if the pSwapValue value is stored in the address specified by pAddress) </p></result> <SIL2/>

InOut:

Scope	Name	Type	Comment
Return	`SysCpuAtomicCompareAndSwap`	`RTS_IEC_RESULT`
Input	`pAddress`	POINTER TO BYTE	pointer to the value to test
	`pSwapValue`	POINTER TO BYTE	pointer to new valid
	`pCompareValue`	POINTER TO BYTE	pointer to compare value
	`valueSize`	`USINT`	size of the value

SysCpuAtomicCompareAndSwap (FUN)

`SysCpuAtomicCompareAndSwap` (FUN)