Unable to connect to target device - STM32H7S3L8H6 (NUCLEO-H7S3L8)

[neo-knight-td]

Dear all,

I have purchased the NUCLEO-H7S3L8. I am facing an issue when trying to debug a basic (blank) project. The Debugger is unable to connect to the target. Here is the console output :

"

STMicroelectronics ST-LINK GDB server. Version 7.10.0

Copyright (c) 2025, STMicroelectronics. All rights reserved.

Starting server with the following options:

Persistent Mode : Disabled

Logging Level : 1

Listen Port Number : 61234

Status Refresh Delay : 15s

Verbose Mode : Disabled

SWD Debug : Enabled

InitWhile : Enabled

Waiting for debugger connection...

Debugger connected

Waiting for debugger connection...

Debugger connected

Waiting for debugger connection...

-------------------------------------------------------------------

STM32CubeProgrammer v2.19.0

-------------------------------------------------------------------

Log output file: /tmp/STM32CubeProgrammer_fldzzj.log

ST-LINK SN : 0020002B3433511830343835

ST-LINK FW : V3J16M7

Board : NUCLEO-H7S3L8

Voltage : 3,30V

SWD freq : 8000 KHz

Connect mode: Under Reset

Reset mode : Hardware reset

Device ID : 0x485

Revision ID : Rev B

Device name : STM32H7RSxx

Flash size : 64 KBytes (default)

Device type : MCU

Device CPU : Cortex-M7

BL Version : 0xE4

Opening and parsing file: ST-LINK_GDB_server_YZEder.srec

Memory Programming ...

File : ST-LINK_GDB_server_YZEder.srec

Size : 6.39 KB

Address : 0x08000000

Erasing memory corresponding to sector 0:

Erasing internal memory sector 0

Download in Progress:

File download complete

Time elapsed during download operation: 00:00:00.057

-------------------------------------------------------------------

STM32CubeProgrammer v2.19.0

-------------------------------------------------------------------

Log output file: /tmp/STM32CubeProgrammer_MGG0Vd.log

Error: Unable to connect to the target device, Access port is not valid.

Encountered Error when opening /opt/st/stm32cubeide_1.18.1/plugins/com.st.stm32cube.ide.mcu.externaltools.cubeprogrammer.linux64_2.2.100.202412061334/tools/bin/STM32_Programmer_CLI

Error in STM32CubeProgrammer

Shutting down...

Exit.

"

The project I am trying to debug is the standard code generated when creating a new project in STM32CubeIDE. The only thing I changed is the Debugger Configuration (I changed it iaw this guide : https://community.st.com/t5/stm32-mcus/stm32cubeide-how-to-debug-an-stm32h7rx-sx-project-without/ta-p/737120).

I have already tried a mass erase (using the BOOT0 pin and STM32 Programmer) but the issue persists.

Can someone assist me on how to launch a Debug session (even from an Example project) with the NUCLEO-H7S3L8 ?

[KDJEM.1]

Hello @neo-knight-td and welcome to the community;

Are you able to connect your board using STM32CubeProgrammer toolchain?

Could you please

• Try to refer and follow the steps shared in this FAQ: How can I recover my STM32H7 board after facing a power configuration deadlock?
• Try to upgrade Firmware using STM32CubeProgrammer and erase external memory.
• If you run an STM32Cube_FW_H7RS example, it is recommended to check the readme file for the HSLV bits level. Please take look at this FAQ.

I hope this help you.

Thank you.

Kaouthar

[AScha.3]

Hi,

so you are on a Linux system, IDE 1.18.1 ; can you debug any other board ?

because maybe your system missing the outdated libs, libncurses.so.5 etc,  IDE still expects.

Read here in forum about solutions... just search : libncurses.so.5 .

[neo-knight-td]

Hi @KDJEM.1 ,

As I said, I am able to connect with STM32CubeProgrammer when setting the BOOT0 pin high.

I tried the two power configuration : 

/*!< Supply configuration update enable */
HAL_PWREx_ConfigSupply(PWR_DIRECT_SMPS_SUPPLY);

Or

/*!< Supply configuration update enable */
HAL_PWREx_ConfigSupply(PWR_LDO_SUPPLY);

None has worked for me.

I have done a mass erase using STM32CubeProgrammer, but I am still not able to debug the base project with that.

I looked at the HSLV bits. I don't see them being modified anywhere in the code. By default (after the mass erase), they are unset.

I am not trying an example yet. I have just opened a new blank project for the NUCLEO-H7S3L8 but even this is undebuggable.

Do you have any other suggestion ?