(*
  GVL: GVL_IO
  Option C relay feedback only. EL2809 DO: map channels directly in the device tree
  to NVL_Out (e.g. NVL_Out.l_open_plan_living_room.l_1..l_6, ...) and boiler relay.
  Initialize EtherCAT_RelayFeedback to zero at startup (or use default init).
*)
VAR_GLOBAL
    // ---------- Option C: relay feedback (copy of output for next cycle) ----------
    EtherCAT_RelayFeedback: STRUCT
        open_plan_living_room: struct_room_outs;
        open_plan_dining_room: struct_room_outs;
        open_plan_entrance: struct_room_outs;
        open_plan_guest_wc: struct_room_outs;
        kitchen_kitchen: struct_room_outs;
        kitchen_pantry: struct_room_outs;
        bedrooms_office: struct_room_outs;
        bedrooms_hallway: struct_room_outs;
        bedrooms_laundry: struct_room_outs;
        bedrooms_shower: struct_room_outs;
        bedrooms_bedroom: struct_room_outs;
        master_bedroom_suite: struct_room_outs;
        master_bedroom_bathroom: struct_room_outs;
        exterior_veranda: struct_room_outs;
        exterior_entrance: struct_room_outs;
        exterior_yard: struct_room_outs;
    END_STRUCT;
END_VAR
