diff --git a/max3421e.h b/max3421e.h
index 9fdff593..21138be4 100644
--- a/max3421e.h
+++ b/max3421e.h
@@ -27,9 +27,6 @@ e-mail   :  support@circuitsathome.com
 
 //#define MAX_GPX   8
 
-#define ON  true
-#define OFF false
-
 #define SE0     0
 #define SE1     1
 #define FSHOST  2
diff --git a/usbhost.h b/usbhost.h
index efadcabf..fe0cdda6 100644
--- a/usbhost.h
+++ b/usbhost.h
@@ -60,8 +60,8 @@ typedef SPi< Pb7, Pb5, Pb6, Pb4 > spi;
 #endif
 
 typedef enum VBUS_t {
-        on = 0,
-        off = GPX_VBDET
+        vbus_on = 0,
+        vbus_off = GPX_VBDET
 };
 
 template< typename SS, typename INTR > class MAX3421e /* : public spi */ {