The AT Declaration in CoDeSys is only for Physical Addresses like %IW80 and so on.
To solve Problems like this i use Pointer.
bytARR : ARRAY[0..3] OF BYTE;
dwHELP : POINTER TO DWORD;
TEST : DWORD; (* Example *)
(* Get the Adress of the Array *)
dwHELP := ADR(bytARR);
(* Read the ByteArray Value in an DWORD *)
TEST := dwHELP^;
(* Write an DWORD Value to an ByteArray *)
dwHELP^ := TEST;
Pay attention to the ^
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