diff --git a/libraries/AP_HAL/board/linux.h b/libraries/AP_HAL/board/linux.h
index 78eba130d9..67faddea01 100644
--- a/libraries/AP_HAL/board/linux.h
+++ b/libraries/AP_HAL/board/linux.h
@@ -82,7 +82,7 @@
 #elif CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_VNAV
     // linux SBC with VectorNav AHRS
     #define HAL_EXTERNAL_AHRS_DEFAULT 1
-    #define HAL_SERIAL3_PROTOCOL 36
+    #define DEFAULT_SERIAL3_PROTOCOL 36
     #define HAL_AIRSPEED_TYPE_DEFAULT 0
     #define HAL_GPS_TYPE_DEFAULT 21
     #define HAL_AHRS_EKF_TYPE_DEFAULT 11