diff --git a/src/platforms/px4_micro_hal.h b/src/platforms/px4_micro_hal.h
index d992ba16c3..68840c9472 100644
--- a/src/platforms/px4_micro_hal.h
+++ b/src/platforms/px4_micro_hal.h
@@ -206,6 +206,7 @@ __BEGIN_DECLS
 #    // Fixme: using ??
 #    define PX4_BBSRAM_SIZE          2048
 #    define PX4_BBSRAM_GETDESC_IOCTL 0
+#    define PX4_NUMBER_I2C_BUSES     SAMV7_NTWIHS
 
 //todo:define this for Atmel and add loader.
 /* Atmel defines the 128 bit UUID as