diff --git a/lopper/assists/bmcmake_metadata_xlnx.py b/lopper/assists/bmcmake_metadata_xlnx.py
index 5b90d40c..a92cd722 100644
--- a/lopper/assists/bmcmake_metadata_xlnx.py
+++ b/lopper/assists/bmcmake_metadata_xlnx.py
@@ -202,7 +202,7 @@ def lwip_topolgy(outdir, config):
     }},'''
     topology_str += f'''
     {{
-        NULL
+        0
     }}
 }};'''
     topology_fd.write(topology_str)