diff --git a/solution/tc_project_app/GVLs/GVL_APP.TcGVL b/solution/tc_project_app/GVLs/GVL_APP.TcGVL
index 8a98ec7..aae7171 100644
--- a/solution/tc_project_app/GVLs/GVL_APP.TcGVL
+++ b/solution/tc_project_app/GVLs/GVL_APP.TcGVL
@@ -8,7 +8,8 @@ VAR_GLOBAL
 END_VAR
 
 VAR_GLOBAL CONSTANT
-    nAXIS_NUM : UINT:=0;
+    nAXIS_NUM : UINT:=0; (*~ (OPC: 1 : available for OPC-clients)
+                         (OPC_PROP[0005]: 1 : OPC_PROP_RIGHTS, here read only) *)
 END_VAR]]></Declaration>
   </GVL>
 </TcPlcObject>
\ No newline at end of file