diff --git a/cmake/configs/nuttx_px4fmu-v2_default.cmake b/cmake/configs/nuttx_px4fmu-v2_default.cmake
index c3a3586f66..62f96b12d4 100644
--- a/cmake/configs/nuttx_px4fmu-v2_default.cmake
+++ b/cmake/configs/nuttx_px4fmu-v2_default.cmake
@@ -2,6 +2,8 @@ include(nuttx/px4_impl_nuttx)
 
 set(CMAKE_TOOLCHAIN_FILE ${CMAKE_SOURCE_DIR}/cmake/toolchains/Toolchain-arm-none-eabi.cmake)
 
+set(config_uavcan_num_ifaces 2)
+
 set(config_module_list
 	#
 	# Board support modules
diff --git a/cmake/configs/nuttx_px4fmu-v4_default.cmake b/cmake/configs/nuttx_px4fmu-v4_default.cmake
index 858c95dd05..720b9e74b8 100644
--- a/cmake/configs/nuttx_px4fmu-v4_default.cmake
+++ b/cmake/configs/nuttx_px4fmu-v4_default.cmake
@@ -2,6 +2,8 @@ include(nuttx/px4_impl_nuttx)
 
 set(CMAKE_TOOLCHAIN_FILE ${CMAKE_SOURCE_DIR}/cmake/toolchains/Toolchain-arm-none-eabi.cmake)
 
+set(config_uavcan_num_ifaces 1)
+
 set(config_module_list
 	#
 	# Board support modules
diff --git a/src/modules/uavcan/CMakeLists.txt b/src/modules/uavcan/CMakeLists.txt
index ce348ec910..18ddc0f261 100644
--- a/src/modules/uavcan/CMakeLists.txt
+++ b/src/modules/uavcan/CMakeLists.txt
@@ -41,7 +41,7 @@ add_definitions(
 		-DUAVCAN_NO_ASSERTIONS
 		-DUAVCAN_PLATFORM=stm32
 		-DUAVCAN_STM32_${OS_UPPER}=1
-		-DUAVCAN_STM32_NUM_IFACES=2
+		-DUAVCAN_STM32_NUM_IFACES=${config_uavcan_num_ifaces}
 		-DUAVCAN_STM32_TIMER_NUMBER=5
 		)