diff --git a/extruder/watchdog.c b/extruder/watchdog.c
index e4e4306..f31b42e 100644
--- a/extruder/watchdog.c
+++ b/extruder/watchdog.c
@@ -16,7 +16,9 @@
 #include	<avr/interrupt.h>
 
 #include	"arduino.h"
-#include	"serial.h"
+#ifndef	EXTRUDER
+	#include	"serial.h"
+#endif
 
 volatile uint8_t	wd_flag = 0;
 
diff --git a/watchdog.c b/watchdog.c
index e4e4306..f31b42e 100644
--- a/watchdog.c
+++ b/watchdog.c
@@ -16,7 +16,9 @@
 #include	<avr/interrupt.h>
 
 #include	"arduino.h"
-#include	"serial.h"
+#ifndef	EXTRUDER
+	#include	"serial.h"
+#endif
 
 volatile uint8_t	wd_flag = 0;