.. zephyr:board:: stm32h747i_disco

Overview

The discovery kit enables a wide diversity of applications taking benefit from audio, multi-sensor support, graphics, security, video, and high-speed connectivity features.

The board includes an STM32H747XI SoC with a high-performance DSP, Arm Cortex-M7 + Cortex-M4 MCU, with 2MBytes of Flash memory, 1MB RAM, 480 MHz CPU, Art Accelerator, L1 cache, external memory interface, large set of peripherals, SMPS, and MIPI-DSI.

Additionally, the board features:

On-board ST-LINK/V3E supporting USB reenumeration capability
USB ST-LINK functions: virtual COM port, mass storage, debug port
Flexible power-supply options:
- ST-LINK USB VBUS, USB OTG HS connector, or external sources
4” capacitive touch LCD display module with MIPI® DSI interface
Ethernet compliant with IEEE802.3-2002
USB OTG HS
Stereo speaker outputs
ST-MEMS digital microphones
2 x 512-Mbit QUAD-SPI NOR Flash memory
256-Mbit SDRAM
4 color user LEDs
1 user and reset push-button
4-direction joystick with selection button
Arduino Uno V3 connectors

More information about the board can be found at the STM32H747I-DISCO website_. More information about STM32H747XIH6 can be found here:

STM32H747XI on www.st.com_
STM32H747xx reference manual_
STM32H747xx datasheet_

Supported Features

.. zephyr:board-supported-hw::

.. note: From UM2411 Rev 4: With the default setting, the Ethernet feature is not working because of a conflict between ETH_MDC and SAI4_D1 of the MEMs digital microphone. Make sure you have SB8 closed and SB21 open to get Ethernet working.

Pin Mapping

STM32H747I Discovery kit has 9 GPIO controllers. These controllers are responsible for pin muxing, input/output, pull-up, etc.

For more details please refer to STM32H747I-DISCO website_.

Default Zephyr Peripheral Mapping:

UART_1 TX/RX : PA9/PA10 (ST-Link Virtual Port Com)
UART_8 TX/RX : PJ8/PJ9 (Arduino Serial)
SPI_5 NSS/SCK/MISO/MOSI : PK1/PK0/PJ11/PJ10 (Arduino SPI)
SDMMC_1 D0/D1/D2/D3/CK/CMD: PC8/PC9/PC10/PC11/PC12/PD2
LD1 : PI12
LD2 : PI13
LD3 : PI14
LD4 : PI15
W-UP : PC13
J-CENTER : PK2
J-DOWN : PK3
J-LEFT : PK4
J-RIGHT : PK5
J-UP : PK6

System Clock

The STM32H747I System Clock can be driven by an internal or external oscillator, as well as by the main PLL clock. By default, the CPU1 (Cortex-M7) System clock is driven by the PLL clock at 400MHz, and the CPU2 (Cortex-M4) System clock is driven at 200MHz. PLL clock is feed by a 25MHz high speed external clock.

Serial Port

The STM32H747I Discovery kit has up to 8 UARTs. Default configuration assigns USART1 and UART8 to the CPU1. The Zephyr console output is assigned to UART1 which connected to the onboard ST-LINK/V3.0. Virtual COM port interface. Default communication settings are 115200 8N1.

Ethernet

Disclaimer: This section is mostly copy-paste of corresponding DISCO_H747I modifications for Ethernet_ mbed blog post. The author of this article sincerely allowed to use the images and his knowledge about necessary HW modifications to get Ethernet working with this board.

To get Ethernet working following HW modifications are required:

SB21, SB45 and R87 should be opened
SB22, SB44, SB17 and SB8 should be closed

Following two images shows necessary changes on the board marked:

.. image:: img/disco_h747i_ethernet_modification_1.jpg :align: center :alt: STM32H747I-DISCO - Ethernet modification 1 (SB44, SB45)

.. image:: img/disco_h747i_ethernet_modification_2.jpg :align: center :alt: STM32H747I-DISCO - Ethernet modification 2 (SB21, R87, SB22, SB17 and SB8)

Display

The STM32H747I Discovery kit has a dedicated DSI LCD connector CN15, where the MB1166 (B-LCD40-DSI1) display extension board can be mounted. Enable display support in Zephyr by adding the shield st_b_lcd40_dsi1_mb1166 or st_b_lcd40_dsi1_mb1166_a09 to your build command, for example:

.. zephyr-app-commands:: :zephyr-app: samples/drivers/display :board: stm32h747i_disco/stm32h747xx/m7 :shield: st_b_lcd40_dsi1_mb1166 :goals: build flash

.. note:: The shield comes in different hardware revisions, the MB1166-A09 is utilizing a NT35510 panel controller and shall specifically use st_b_lcd40_dsi1_mb1166_a09 as SHIELD when building. Prior versions are utilizing an OTM8009a controller and shall use shield name without postfix, that is: st_b_lcd40_dsi1_mb1166. Shield version is printed on a sticker placed below the two bottom mounting holes and has the format: MB1166-Axx.

The dual core nature of STM32H747 SoC requires sharing HW resources between the two cores. This is done in 3 ways:

Compilation: Clock configuration is only accessible to M7 core. M4 core only has access to bus clock activation and deactivation.
Static pre-compilation assignment: Peripherals such as a UART are assigned in devicetree before compilation. The user must ensure peripherals are not assigned to both cores at the same time.
Run time protection: Interrupt-controller and GPIO configurations could be accessed by both cores at run time. Accesses are protected by a hardware semaphore to avoid potential concurrent access issues.

Programming and Debugging

.. zephyr:board-supported-runners::

STM32H747I-DISCO board includes an ST-LINK/V3 embedded debug tool interface.

Applications for the stm32h747i_disco board should be built per core target, using either stm32h747i_disco/stm32h747xx/m7 or stm32h747i_disco/stm32h747xx/m4 as the target. See :ref:build_an_application for more information about application builds.

.. note::

Check if the board's ST-LINK V3 has the newest FW version. It can be updated using STM32CubeProgrammer_.

.. note::

With OpenOCD, sometimes, flashing does not work. It is necessary to erase the flash (with STM32CubeProgrammer for example) to make it work again. Debugging with OpenOCD is currently working for this board only with Cortex M7, not Cortex M4.

Flashing

Flashing operation will depend on the target to be flashed and the SoC option bytes configuration.

The board is configured to be flashed using west STM32CubeProgrammer_ runner for both cores, so its :ref:installation <stm32cubeprog-flash-host-tools> is required. The target core is detected automatically.

Alternatively, OpenOCD or JLink can also be used to flash the board using the --runner (or -r) option:

.. code-block:: console

$ west flash --runner openocd $ west flash --runner jlink

It is advised to use STM32CubeProgrammer_ to check and update option bytes configuration.

By default:

CPU1 (Cortex-M7) boot address is set to 0x80000000 (OB: BOOT_CM7_ADD0)
CPU2 (Cortex-M4) boot address is set to 0x81000000 (OB: BOOT_CM4_ADD0)

Also, default out of the box board configuration enables CM7 and CM4 boot when board is powered (Option bytes BCM7 and BCM4 are checked). It is possible to change Option Bytes so that CM7 boots first in stand alone, and CM7 will wakeup CM4 after clock initialization. Drivers are able to take into account both Option Bytes configurations automatically.

Zephyr flash configuration has been set to meet these default settings.

Flashing an application to STM32H747I M7 Core

First, connect the STM32H747I Discovery kit to your host computer using the USB port to prepare it for flashing. Then build and flash your application.

Here is an example for the :zephyr:code-sample:hello_world application.

.. zephyr-app-commands:: :zephyr-app: samples/hello_world :board: stm32h747i_disco/stm32h747xx/m7 :goals: build flash

Run a serial host program to connect with your board:

.. code-block:: console

$ minicom -D /dev/ttyACM0

You should see the following message on the console:

.. code-block:: console

Hello World! stm32h747i_disco

.. note:: Sometimes, flashing is not working. It is necessary to erase the flash (with STM32CubeProgrammer for example) to make it work again.

Similarly, you can build and flash samples on the M4 target. For this, please take care of the resource sharing (UART port used for console for instance).

Here is an example for the :zephyr:code-sample:blinky application on M4 core.

.. zephyr-app-commands:: :zephyr-app: samples/basic/blinky :board: stm32h747i_disco/stm32h747xx/m4 :goals: build flash