diff --git a/monitor/display.h b/monitor/display.h
index 2740f76..4c7b418 100644
--- a/monitor/display.h
+++ b/monitor/display.h
@@ -24,6 +24,8 @@
 
 #include <stdbool.h>
 
+#define print_field(fmt, args...) printf("%-8c" fmt "\n", ' ', ## args)
+
 bool use_color(void);
 int num_columns(void);
 
diff --git a/monitor/l2cap.c b/monitor/l2cap.c
index 63f7f48..0675e93 100644
--- a/monitor/l2cap.c
+++ b/monitor/l2cap.c
@@ -29,10 +29,9 @@
 #include <bluetooth/bluetooth.h>
 
 #include "packet.h"
+#include "display.h"
 #include "l2cap.h"
 
-#define print_field(fmt, args...) printf("%-8c" fmt "\n", ' ', ## args)
-
 struct sig_opcode_data {
 	uint8_t opcode;
 	const char *str;
diff --git a/monitor/packet.c b/monitor/packet.c
index 3f8b22b..4cf246e 100644
--- a/monitor/packet.c
+++ b/monitor/packet.c
@@ -238,8 +238,6 @@ static void print_packet(struct timeval *tv, uint16_t index, char ident,
 		printf("%s\n", line);
 }
 
-#define print_field(fmt, args...) printf("%-8c" fmt "\n", ' ', ## args)
-
 static const struct {
 	uint8_t error;
 	const char *str;