diff --git a/RFM69registers.h b/RFM69registers.h
index 2d815ec..b02fbbb 100644
--- a/RFM69registers.h
+++ b/RFM69registers.h
@@ -903,12 +903,12 @@
 #define RF_DIOMAPPING2_DIO5_10            0x20
 #define RF_DIOMAPPING2_DIO5_11            0x30
 
-#define RF_DIOMAPPING2_CLKOUT_32          0x00
-#define RF_DIOMAPPING2_CLKOUT_16          0x01
-#define RF_DIOMAPPING2_CLKOUT_8           0x02
-#define RF_DIOMAPPING2_CLKOUT_4           0x03
-#define RF_DIOMAPPING2_CLKOUT_2           0x04
-#define RF_DIOMAPPING2_CLKOUT_1           0x05  // Reset value
+#define RF_DIOMAPPING2_CLKOUT_32MHZ       0x00
+#define RF_DIOMAPPING2_CLKOUT_16MHZ       0x01
+#define RF_DIOMAPPING2_CLKOUT_8MHZ        0x02
+#define RF_DIOMAPPING2_CLKOUT_4MHZ        0x03
+#define RF_DIOMAPPING2_CLKOUT_2MHZ        0x04
+#define RF_DIOMAPPING2_CLKOUT_1MHZ        0x05  // Reset value
 #define RF_DIOMAPPING2_CLKOUT_RC          0x06
 #define RF_DIOMAPPING2_CLKOUT_OFF         0x07  // Recommended default