diff --git a/boards/arm/stm32/stm32f429i-disco/configs/gdbstub/defconfig b/boards/arm/stm32/stm32f429i-disco/configs/gdbstub/defconfig
new file mode 100644
index 0000000000..7b6f26d781
--- /dev/null
+++ b/boards/arm/stm32/stm32f429i-disco/configs/gdbstub/defconfig
@@ -0,0 +1,58 @@
+#
+# This file is autogenerated: PLEASE DO NOT EDIT IT.
+#
+# You can use "make menuconfig" to make any modifications to the installed .config file.
+# You can then do "make savedefconfig" to generate a new defconfig file that includes your
+# modifications.
+#
+# CONFIG_LIBC_FLOATINGPOINT is not set
+# CONFIG_NSH_DISABLE_MW is not set
+# CONFIG_STM32_FLASH_PREFETCH is not set
+CONFIG_ARCH="arm"
+CONFIG_ARCH_BOARD="stm32f429i-disco"
+CONFIG_ARCH_BOARD_STM32F429I_DISCO=y
+CONFIG_ARCH_BUTTONS=y
+CONFIG_ARCH_CHIP="stm32"
+CONFIG_ARCH_CHIP_STM32=y
+CONFIG_ARCH_CHIP_STM32F429Z=y
+CONFIG_ARCH_INTERRUPTSTACK=4096
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_BOARD_LOOPSPERMSEC=16717
+CONFIG_BUILTIN=y
+CONFIG_DEBUG_FEATURES=y
+CONFIG_DEBUG_SYMBOLS=y
+CONFIG_FS_PROCFS=y
+CONFIG_HAVE_CXX=y
+CONFIG_HAVE_CXXINITIALIZE=y
+CONFIG_HEAP2_BASE=0xD0000000
+CONFIG_HEAP2_SIZE=8388608
+CONFIG_INIT_ENTRYPOINT="nsh_main"
+CONFIG_INTELHEX_BINARY=y
+CONFIG_LIB_GDBSTUB=y
+CONFIG_LIB_GDBSTUB_DEBUG=y
+CONFIG_MM_REGIONS=3
+CONFIG_NSH_BUILTIN_APPS=y
+CONFIG_NSH_FILEIOSIZE=512
+CONFIG_NSH_LINELEN=64
+CONFIG_NSH_READLINE=y
+CONFIG_PREALLOC_TIMERS=4
+CONFIG_RAM_SIZE=114688
+CONFIG_RAM_START=0x20000000
+CONFIG_RAW_BINARY=y
+CONFIG_RR_INTERVAL=200
+CONFIG_SCHED_WAITPID=y
+CONFIG_SERIAL_GDBSTUB=y
+CONFIG_SPI=y
+CONFIG_START_DAY=6
+CONFIG_START_MONTH=12
+CONFIG_START_YEAR=2011
+CONFIG_STM32_DISABLE_IDLE_SLEEP_DURING_DEBUG=y
+CONFIG_STM32_EXTERNAL_RAM=y
+CONFIG_STM32_FMC=y
+CONFIG_STM32_JTAG_SW_ENABLE=y
+CONFIG_STM32_PWR=y
+CONFIG_STM32_USART1=y
+CONFIG_STM32_USART3=y
+CONFIG_SYSTEM_NSH=y
+CONFIG_TASK_NAME_SIZE=0
+CONFIG_USART1_SERIAL_CONSOLE=y
diff --git a/boards/arm/stm32/stm32f429i-disco/include/board.h b/boards/arm/stm32/stm32f429i-disco/include/board.h
index cfa65ba030..0cee8a9d2b 100644
--- a/boards/arm/stm32/stm32f429i-disco/include/board.h
+++ b/boards/arm/stm32/stm32f429i-disco/include/board.h
@@ -203,6 +203,8 @@
 #define GPIO_USART1_RX GPIO_USART1_RX_1
 #define GPIO_USART1_TX GPIO_USART1_TX_1
 
+#define GPIO_USART3_RX GPIO_USART3_RX_1
+#define GPIO_USART3_TX GPIO_USART3_TX_1
 /* PWM
  *
  * The STM32F4 Discovery has no real on-board PWM devices, but the board can