diff --git a/apps/netbios/netbios.c b/apps/netbios/netbios.c
index efbb9e4..54547b5 100644
--- a/apps/netbios/netbios.c
+++ b/apps/netbios/netbios.c
@@ -79,24 +79,24 @@
 #define NETBIOS_NAME_TTL 300000
 
 /** NetBIOS header flags */
-#define NETB_HFLAG_RESPONSE           0x8000
-#define NETB_HFLAG_OPCODE             0x7800
-#define NETB_HFLAG_OPCODE_NAME_QUERY  0x0000
-#define NETB_HFLAG_AUTHORATIVE        0x0400
-#define NETB_HFLAG_TRUNCATED          0x0200
-#define NETB_HFLAG_RECURS_DESIRED     0x0100
-#define NETB_HFLAG_RECURS_AVAILABLE   0x0080
-#define NETB_HFLAG_BROADCAST          0x0010
-#define NETB_HFLAG_REPLYCODE          0x0008
-#define NETB_HFLAG_REPLYCODE_NOERROR  0x0000
+#define NETB_HFLAG_RESPONSE           0x8000U
+#define NETB_HFLAG_OPCODE             0x7800U
+#define NETB_HFLAG_OPCODE_NAME_QUERY  0x0000U
+#define NETB_HFLAG_AUTHORATIVE        0x0400U
+#define NETB_HFLAG_TRUNCATED          0x0200U
+#define NETB_HFLAG_RECURS_DESIRED     0x0100U
+#define NETB_HFLAG_RECURS_AVAILABLE   0x0080U
+#define NETB_HFLAG_BROADCAST          0x0010U
+#define NETB_HFLAG_REPLYCODE          0x0008U
+#define NETB_HFLAG_REPLYCODE_NOERROR  0x0000U
 
 /** NetBIOS name flags */
-#define NETB_NFLAG_UNIQUE             0x8000
-#define NETB_NFLAG_NODETYPE           0x6000
-#define NETB_NFLAG_NODETYPE_HNODE     0x6000
-#define NETB_NFLAG_NODETYPE_MNODE     0x4000
-#define NETB_NFLAG_NODETYPE_PNODE     0x2000
-#define NETB_NFLAG_NODETYPE_BNODE     0x0000
+#define NETB_NFLAG_UNIQUE             0x8000U
+#define NETB_NFLAG_NODETYPE           0x6000U
+#define NETB_NFLAG_NODETYPE_HNODE     0x6000U
+#define NETB_NFLAG_NODETYPE_MNODE     0x4000U
+#define NETB_NFLAG_NODETYPE_PNODE     0x2000U
+#define NETB_NFLAG_NODETYPE_BNODE     0x0000U
 
 /** NetBIOS message header */
 #ifdef PACK_STRUCT_USE_INCLUDES