diff --git a/src/ANT_defines.h b/src/ANT_defines.h
index d806978..6d52aac 100644
--- a/src/ANT_defines.h
+++ b/src/ANT_defines.h
@@ -93,8 +93,8 @@
  */
 #define CHANNEL_TYPE_BIDIRECTIONAL_RECEIVE    0x00
 #define CHANNEL_TYPE_BIDIRECTIONAL_TRANSMIT   0x10
-#define CHANNEL_TYPE_UNIDIRECTIONAL_RECEIVE   0x50
-#define CHANNEL_TYPE_UNIDIRECTIONAL_TRANSMIT  0x40
+#define CHANNEL_TYPE_UNIDIRECTIONAL_RECEIVE   0x40
+#define CHANNEL_TYPE_UNIDIRECTIONAL_TRANSMIT  0x50
 #define CHANNEL_TYPE_SHARED_RECEIVE           0x20
 #define CHANNEL_TYPE_SHARED_TRANSMIT          0x30