Assignment operator REF=

The operator generates a reference (pointer) to a value.

Syntax:

<variable name> REF= <variable name>

Sample:

PROGRAM MAIN
VAR
    refA  : REFERENCE TO ST_Sample;
    stA   : ST_Sample;
    refB  : REFERENCE TO ST_Sample;
    stB1  : ST_Sample;
    stB2  : ST_Sample;
END_VAR

refA REF= stA;   // represents => refA  := ADR(stA);
refB REF= stB1;  // represents => refB  := ADR(stB1);
refA := refB;    // represents => refA^ := refB^; (value assignment of refB as refA and refB are implicitly dereferenced) 
refB := stB2;    // represents => refB^ := stB2; (value assignment of stB2 as refB is implicitly dereferenced)
END_VAR