diff --git a/printhex.h b/printhex.h
index d26b691a..b3364a8f 100644
--- a/printhex.h
+++ b/printhex.h
@@ -23,6 +23,8 @@ e-mail   :  support@circuitsathome.com
 #include <WProgram.h>
 #endif
 
+#define USB_HOST_SERIAL Serial
+
 void E_Notifyc(char c, int lvl);
 
 template <class T>