// Source code example and possible behavior of other programming environments
VAR
number_1 : INT := 123;
number_2 : INT := 456;
ref_1 : REFERENCE TO INT;
ref_2 : REFERENCE TO INT;
END_VAR
ref_1 := ADR(number_1);
ref_2 := ADR(number_2);
ref_2 := ref_1; // ref_2^ = number_2 = number_1 = 123
The reference ref_2 still points to number_2, but the value of number_1 is copied to number_2.
With SIMATIC AX, using dereferenced references (e.g. ref_2^ := ref_1^;) gives the same result.