.. zephyr:board:: gd32f407v_start

Overview
********

The GD32F407V-START board is a hardware platform that enables prototyping
on GD32F407VE Cortex-M4 High Performance MCU.

The GD32F407VE features a single-core ARM Cortex-M4 MCU which can run up
to 168 MHz with flash accesses zero wait states, 3072kiB of Flash, 192kiB of
SRAM and 82 GPIOs.

Hardware
********

- GD32F407VET6 MCU
- 1 x User LEDs
- 1 x User Push buttons
- 1 x USART
- GD-Link on board programmer
- J-Link/SWD connector

For more information about the GD32F407 SoC and GD32F407V-START board:

- `GigaDevice Cortex-M4 High Performance SoC Website`_
- `GD32F407X Datasheet`_
- `GD32F40X User Manual`_
- `GD32F407V-START User Manual`_

Supported Features
==================

.. zephyr:board-supported-hw::

Serial Port
===========

The GD32F407V-START board has one serial communication port. The default port
is USART0 with TX connected at PB6 and RX at PB7.

Programming and Debugging
*************************

.. zephyr:board-supported-runners::

Before programming your board make sure to configure boot jumpers as
follows:

- JP3/4: Select 2-3 for both (boot from user memory)

Using GD-Link or J-Link
=======================

The board comes with an embedded GD-Link programmer.
You need to install CMSIS-Pack which is required by pyOCD
when programming or debugging by the GD-Link programmer.
Execute the following command to install CMSIS-Pack for GD32F407VK
if not installed yet.

   .. code-block:: console

      pyocd pack install gd32f407vk

Also, J-Link can be used to program the board via the SWD interface
(PA13/SWDIO and PA14/SWCLK in the JP6 header).

#. Build the Zephyr kernel and the :zephyr:code-sample:`hello_world` sample application:

   .. zephyr-app-commands::
      :zephyr-app: samples/hello_world
      :board: gd32f407v_start
      :goals: build
      :compact:

#. Connect Serial-USB adapter to PB6, PB7, and GND.

#. Run your favorite terminal program to listen for output. On Linux the
   terminal should be something like ``/dev/ttyUSB0``. For example:

   .. code-block:: console

      minicom -D /dev/ttyUSB0 -o

   The -o option tells minicom not to send the modem initialization
   string. Connection should be configured as follows:

      - Speed: 115200
      - Data: 8 bits
      - Parity: None
      - Stop bits: 1

#. To flash an image:

   .. zephyr-app-commands::
      :zephyr-app: samples/hello_world
      :board: gd32f407v_start
      :goals: flash
      :compact:

   When using J-Link, append ``--runner jlink`` option after ``west flash``.

   You should see "Hello World! gd32f407v_start" in your terminal.

#. To debug an image:

   .. zephyr-app-commands::
      :zephyr-app: samples/hello_world
      :board: gd32f407v_start
      :goals: debug
      :compact:

   When using J-Link, append ``--runner jlink`` option after ``west debug``.

.. _GigaDevice Cortex-M4 High Performance SoC Website:
   https://www.gigadevice.com/products/microcontrollers/gd32/arm-cortex-m4/high-performance-line/

.. _GD32F407X Datasheet:
   https://gd32mcu.com/data/documents/datasheet/GD32F407xx_Datasheet_Rev2.5.pdf

.. _GD32F40X User Manual:
   https://gd32mcu.com/data/documents/userManual/GD32F4xx_User_Manual_Rev2.7.pdf

.. _GD32F407V-START User Manual:
   https://www.gd32mcu.com/data/documents/evaluationBoard/GD32F4xx_Demo_Suites_V2.6.1.rar
