Nucleo H755ZI-Q

Overview

The NUCLEO-H755ZI-Q board, based on the MB1363 reference board, provides an affordable and flexible way for users to try out new concepts and build prototypes on the STM32H755ZIT6 microcontroller.

The ST Zio connector, which extends the ARDUINO® Uno V3 connectivity, and the ST morpho headers provide an easy means of expanding the functionality of the Nucleo open development platform with a wide choice of specialized shields. The NUCLEO-H755ZI-Q board does not require any separate probe as it integrates the ST-LINK V3 debugger/programmer.

Key Features

  • STM32H755ZIT6 microcontroller in LQFP144 package

  • Ethernet compliant with IEEE-802.3-2002 (depending on STM32 support)

  • USB OTG or full-speed device (depending on STM32 support)

  • 3 user LEDs

  • 2 user and reset push-buttons

  • 32.768 kHz crystal oscillator

  • Board connectors:

  • USB with Micro-AB

  • Ethernet RJ45 (depending on STM32 support)

  • SWDST Zio connector including Arduino* Uno V3ST

  • ST morpho expansion

  • Flexible power-supply options: ST-LINK USB VBUS or external sources

  • External or internal SMPS to generate Vcore logic supply

  • On-board ST-LINK/V3 debugger/programmer with USB re-enumeration

  • capability: mass storage, virtual COM port and debug port

  • USB OTG full speed or device only

More information about the board can be found at the Nucleo H755ZI-Q website.

Hardware

Nucleo H755ZI-Q provides the following hardware components:

  • STM32H755ZI in LQFP144 package

  • ARM 32-bit Cortex-M7 CPU with FPU

  • ARM 32-bit Cortex-M4 CPU with FPU

  • Chrom-ART Accelerator

  • Hardware JPEG Codec

  • 480 MHz max CPU frequency

  • VDD from 1.62 V to 3.6 V

  • 2 MB Flash

  • 1 MB SRAM

  • High-resolution timer (2.1 ns)

  • 32-bit timers(2)

  • 16-bit timers(12)

  • SPI(6)

  • I2C(4)

  • I2S (3)

  • USART(4)

  • UART(4)

  • USB OTG Full Speed and High Speed(1)

  • USB OTG Full Speed(1)

  • CAN-FD(2)

  • SAI(2)

  • SPDIF_Rx(4)

  • HDMI_CEC(1)

  • Dual Mode Quad SPI(1)

  • Camera Interface

  • GPIO (up to 114) with external interrupt capability

  • 16-bit ADC(3) with 36 channels / 3.6 MSPS

  • 12-bit DAC with 2 channels(2)

  • True Random Number Generator (RNG)

  • 16-channel DMA

  • LCD-TFT Controller with XGA resolution

  • CRYPT and HASH peripherals

Supported Features

The Zephyr nucleo_h755zi_q board configuration supports the following hardware features:

Interface

Controller

Driver/Component

NVIC

on-chip

nested vector interrupt controller

UART/USART

on-chip

serial port

PINMUX

on-chip

pinmux

GPIO

on-chip

gpio

RTC

on-chip

counter

I2C

on-chip

i2c

PWM

on-chip

pwm

ETHERNET

on-chip

ethernet

RNG

on-chip

True Random number generator

USB OTG FS

on-chip

USB device

Other hardware features are not yet supported on this Zephyr port.

The default configuration per core can be found in the defconfig files: boards/st/nucleo_h755zi_q/nucleo_h755zi_q_stm32h755xx_m7_defconfig and boards/st/nucleo_h755zi_q/nucleo_h755zi_q_stm32h755xx_m4_defconfig

For mode details please refer to STM32 Nucleo-144 board User Manual.

Default Zephyr Peripheral Mapping:

The Nucleo H755ZI board features a ST Zio connector (extended Arduino Uno V3) and a ST morpho connector. Board is configured as follows:

  • USART_3 TX/RX : PD8/PD9 (ST-Link Virtual Port Com)

  • USER_PB : PC13

  • LD1 : PA5

  • LD2 : PE1

  • LD3 : PB14

  • I2C : PB8, PB9

System Clock

Nucleo H755ZI-Q System Clock can be driven by an internal or external oscillator, as well as the main PLL clock. By default, the System clock is driven by the PLL clock at 480MHz, driven by an 8MHz high-speed external clock.

Serial Port

Nucleo H755ZI-Q board has 4 UARTs and 4 USARTs. The Zephyr console output is assigned to USART3. Default settings are 115200 8N1.

Resources sharing

The dual core nature of STM32H755 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

Nucleo H755ZI-Q board includes an ST-LINK/V3 embedded debug tool interface.

Applications for the nucleo_h755zi_q board should be built per core target, using either nucleo_h755zi_q/stm32h755xx/m7 or nucleo_h755zi_q/stm32h755xx/m4 as the target (see Building an Application and Run an Application for more details).

Note

Check if the board’s ST-LINK/V3 has the newest firmware version. It can be updated with STM32CubeProgrammer

Flashing

The board is configured to be flashed using west STM32CubeProgrammer runner for both cores, so its installation is required. The target core is detected automatically.

It is advised to use STM32CubeProgrammer to check and update option bytes configuration and flash nucleo_h755zi_q/stm32h755xx/m7 and nucleo_h755zi_q/stm32h755xx/m4 board targets.

By default:

  • CPU0 (Cortex-M7) boot address is set to 0x08000000 (OB: BOOT_CM7_ADD0)

  • CPU1 (Cortex-M4) boot address is set to 0x08100000 (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). In that configuration, Kconfig boot option STM32H7_BOOT_CM4_CM7 should be selected. Zephyr flash configuration has been set to meet these default settings.

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

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

Flashing an application to STM32H755ZI M7 Core

First, connect the NUCLEO-H755ZI-Q 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 Hello World application.

Run a serial host program to connect with your NUCLEO-H755ZI-Q board.

$ minicom -b 115200 -D /dev/ttyACM0

or use screen:

$ screen /dev/ttyACM0 115200

Build and flash the application:

# From the root of the zephyr repository
west build -b nucleo_h755zi_q/stm32h755xx/m7 samples/hello_world
west flash

You should see the following message on the console:

$ Hello World! nucleo_h755zi_q/stm32h755xx/m7

Note

Sometimes, flashing via OpenOCD does not work. 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 Blinky application on M4 core.

# From the root of the zephyr repository
west build -b nucleo_h755zi_q/stm32h755xx/m4 samples/basic/blinky
west flash

Note

Flashing both M4 and M7 and pushing RESTART button on the board leads to LD1 and LD2 flashing simultaneously.

Debugging

You can debug an application on the Cortex M7 core in the usual way. Here is an example for the Hello World application.

# From the root of the zephyr repository
west build -b nucleo_h755zi_q/stm32h755xx/m7 samples/hello_world
west debug

Debugging a Zephyr application on Cortex M4 side with west is currently not available. As a workaround, STM32CubeIDE can be used.