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Kshor
Associate
September 17, 2026
Question

STM32H7RS-DK Open Bootloader – “Timeout error occurred while waiting for acknowledgement”

  • September 17, 2026
  • 1 reply
  • 34 views

Hello ST Community,

I am working with the STM32H7RS-DK (STM32H7S78-DK) board and trying to program/activate the Open Bootloader using STM32CubeProgrammer.

The Open Bootloader .bin file downloads successfully to RAM, but the Init Open Bootloader operation fails with an acknowledgement timeout.

  1. Provisionning logs

=====
===== Provisioning of OEMiROT boot path
===== Application selected through env.bat: ..\..\..\Applications\ROT\OEMiROT_Appli
===== Product state must be Open. Execute  \ROT_Provisioning\DA\regression.bat if not the case.
===== DTCM/ITCM_AXI_SHARE is going to be forced to 0 for the provisioning steps
===== (if needed uncomment DTCM/ITCM_AXI_SHARE lines with the wished value in the ob_flash_programming script).
=====

Step 0: Preliminary stage

   * Define product state value (* default choice)
OPEN
       [ OPEN | CLOSED* | LOCKED ]: CLOSED

   * Define Debug Authentication method (* default choice)
       [ CERTIFICATE* | PASSWORD ]: PASSWORD


Step 1: Configuration management

   * OEMiROT_Config.obk generation:
       From TrustedPackageCreator (OBkey tab in Security panel).
       Select OEMiROT_Config.xml(Default path is \ROT_Provisioning\OEMiROT\Config\OEMiROT_Config.xml)
       Warning: Default keys must NOT be used in a product. Make sure to regenerate your own keys
       Run Keygen script to randomly regenerate your own keys (Keys/*.pem)
       Update the configuration (if/as needed) then generate OEMiROT_Config.obk file
       Press any key to continue...

   * Configure OEMiROT_Config.xml for CLOSED or LOCKED
   * Force the update of OEMiROT_Config.obk


   * DA_ConfigWithPassword.obk generation:
       From TrustedPackageCreator (OBkey tab in Security panel).
       Select DA_ConfigWithPassword.xml(Default path is \ROT_Provisioning\DA\Config\DA_ConfigWithPassword.xml)
       Update the configuration (if/as needed) then generate DA_ConfigWithPassword.obk file
       Press any key to continue...

Step 2: Image generations

   * Configure OEMIROT_Boot project as OEMIROT...

   * Boot firmware image generation
       Open the OEMiROT_Boot project with preferred toolchain and rebuild all files.
       At this step the project is configured for OEMiROT boot path.
       Press any key to continue...


   * Code firmware image generation:
       Open the OEMiROT_Appli project with your preferred toolchain
       Rebuild all files. The appli_enc_sign.hex file is generated with the postbuild command
       Press any key to continue...

Step 3: Provisioning

   * Force DTCM/ITCM_AXI_SHARE to 0...
   * Setting the product state PROVISIONING

   * Provisionning the .obk files...
       Successful obk provisioning
       (see "obkey_provisioning.log" for details)

   * Programming the option bytes and flashing the images...
     Error when trying to "Write OEMiROT_Appli Code"
     Programming aborted

=====
===== Error while executing "Programming the option bytes and flashing the images...".
===== See "ob_flash_programming.log" for details. Then try again.
=====

  1. ob_flash_programming.log

AUTO CLOSED NOT_OPEN
Remove Protection and erase All
"C:/Program Files/STMicroelectronics/STM32Cube/STM32CubeProgrammer/bin/STM32_Programmer_CLI.exe" -c port=SWD speed=fast ap=1 mode=Hotplug -obrss 0x5200221c 0x000000ff 0xff 0x00
      -------------------------------------------------------------------
                       STM32CubeProgrammer v2.21.0                  
      -------------------------------------------------------------------

ST-LINK SN  : 001D00423433510F37363934
ST-LINK FW  : V3J16M8
Board       : STM32H7S78-DK
Voltage     : 3.28V
SWD freq    : 8000 KHz
Connect mode: Hot Plug
Reset mode  : Software 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

Reconnecting...
ST-LINK SN  : 001D00423433510F37363934
ST-LINK FW  : V3J16M8
Board       : STM32H7S78-DK
Voltage     : 3.28V
SWD freq    : 8000 KHz
Connect mode: Hot Plug
Reset mode  : Software reset
Device ID   : 0x485
Revision ID : Rev B
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Set Option Bytes RSS succeeded

"C:/Program Files/STMicroelectronics/STM32Cube/STM32CubeProgrammer/bin/STM32_Programmer_CLI.exe" -c port=SWD speed=fast ap=1 mode=Hotplug -obrss 0x52002234 0x03ff03ff 255 0x00
      -------------------------------------------------------------------
                       STM32CubeProgrammer v2.21.0                  
      -------------------------------------------------------------------

ST-LINK SN  : 001D00423433510F37363934
ST-LINK FW  : V3J16M8
Board       : STM32H7S78-DK
Voltage     : 3.27V
SWD freq    : 8000 KHz
Connect mode: Hot Plug
Reset mode  : Software 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

Reconnecting...
ST-LINK SN  : 001D00423433510F37363934
ST-LINK FW  : V3J16M8
Board       : STM32H7S78-DK
Voltage     : 3.27V
SWD freq    : 8000 KHz
Connect mode: Hot Plug
Reset mode  : Software reset
Device ID   : 0x485
Revision ID : Rev B
圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹 100%
Set Option Bytes RSS succeeded

      -------------------------------------------------------------------
                       STM32CubeProgrammer v2.21.0                  
      -------------------------------------------------------------------

ST-LINK SN  : 001D00423433510F37363934
ST-LINK FW  : V3J16M8
Board       : STM32H7S78-DK
Voltage     : 3.28V
SWD freq    : 8000 KHz
Connect mode: Hot Plug
Reset mode  : Software 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


Mass erase ... 

Mass erase successfully achieved
Set SRAM ECC configuration
"C:/Program Files/STMicroelectronics/STM32Cube/STM32CubeProgrammer/bin/STM32_Programmer_CLI.exe" -c port=SWD speed=fast ap=1 mode=Hotplug -ob ECC_ON_SRAM=1
      -------------------------------------------------------------------
                       STM32CubeProgrammer v2.21.0                  
      -------------------------------------------------------------------

ST-LINK SN  : 001D00423433510F37363934
ST-LINK FW  : V3J16M8
Board       : STM32H7S78-DK
Voltage     : 3.27V
SWD freq    : 8000 KHz
Connect mode: Hot Plug
Reset mode  : Software 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


UPLOADING OPTION BYTES DATA ...


  Bank          : 0x01
  Address       : 0x52002200 
  Size          : 32 Bytes

北北北北北北北北北北北北北北北北北北北北北北北北北 0% 圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹 100%

  Bank          : 0x02
  Address       : 0x52002230 
  Size          : 8 Bytes

北北北北北北北北北北北北北北北北北北北北北北北北北 50% 圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹 100%

  Bank          : 0x03
  Address       : 0x52002260 
  Size          : 16 Bytes

北北北北北北北北北北北北北北北北北北北北北北北北北 50% 圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹 100%


PROGRAMMING OPTION BYTES AREA ...
Warning: Option Byte: ecc_on_sram, value: 0x1, was not modified.

Warning: Option Bytes are unchanged, Data won't be downloaded
Time elapsed during option Bytes configuration: 00:00:00.000
Set XSPI1_HSLV configuration (needed to use external memories)
"C:/Program Files/STMicroelectronics/STM32Cube/STM32CubeProgrammer/bin/STM32_Programmer_CLI.exe" -c port=SWD speed=fast ap=1 mode=Hotplug -ob XSPI1_HSLV=1
      -------------------------------------------------------------------
                       STM32CubeProgrammer v2.21.0                  
      -------------------------------------------------------------------

ST-LINK SN  : 001D00423433510F37363934
ST-LINK FW  : V3J16M8
Board       : STM32H7S78-DK
Voltage     : 3.28V
SWD freq    : 8000 KHz
Connect mode: Hot Plug
Reset mode  : Software 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


UPLOADING OPTION BYTES DATA ...


  Bank          : 0x01
  Address       : 0x52002200 
  Size          : 32 Bytes

北北北北北北北北北北北北北北北北北北北北北北北北北 0% 圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹 100%

  Bank          : 0x02
  Address       : 0x52002230 
  Size          : 8 Bytes

北北北北北北北北北北北北北北北北北北北北北北北北北 50% 圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹 100%

  Bank          : 0x03
  Address       : 0x52002260 
  Size          : 16 Bytes

北北北北北北北北北北北北北北北北北北北北北北北北北 50% 圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹 100%


PROGRAMMING OPTION BYTES AREA ...
Warning: Option Byte: xspi1_hslv, value: 0x1, was not modified.

Warning: Option Bytes are unchanged, Data won't be downloaded
Time elapsed during option Bytes configuration: 00:00:00.000
Set XSPI2_HSLV configuration (needed to use external memories)
"C:/Program Files/STMicroelectronics/STM32Cube/STM32CubeProgrammer/bin/STM32_Programmer_CLI.exe" -c port=SWD speed=fast ap=1 mode=Hotplug -ob XSPI2_HSLV=1
      -------------------------------------------------------------------
                       STM32CubeProgrammer v2.21.0                  
      -------------------------------------------------------------------

ST-LINK SN  : 001D00423433510F37363934
ST-LINK FW  : V3J16M8
Board       : STM32H7S78-DK
Voltage     : 3.28V
SWD freq    : 8000 KHz
Connect mode: Hot Plug
Reset mode  : Software 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


UPLOADING OPTION BYTES DATA ...


  Bank          : 0x01
  Address       : 0x52002200 
  Size          : 32 Bytes

北北北北北北北北北北北北北北北北北北北北北北北北北 0% 圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹 100%

  Bank          : 0x02
  Address       : 0x52002230 
  Size          : 8 Bytes

北北北北北北北北北北北北北北北北北北北北北北北北北 50% 圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹 100%

  Bank          : 0x03
  Address       : 0x52002260 
  Size          : 16 Bytes

北北北北北北北北北北北北北北北北北北北北北北北北北 50% 圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹 100%


PROGRAMMING OPTION BYTES AREA ...
Warning: Option Byte: xspi2_hslv, value: 0x1, was not modified.

Warning: Option Bytes are unchanged, Data won't be downloaded
Time elapsed during option Bytes configuration: 00:00:00.000
Write OEMiROT_Boot
"C:/Program Files/STMicroelectronics/STM32Cube/STM32CubeProgrammer/bin/STM32_Programmer_CLI.exe" -c port=SWD speed=fast ap=1 mode=Hotplug -d "C:\Users\kishor.c\STM32Cube\Repository\STM32Cube_FW_H7RS_V1.3.0\Projects\STM32H7S78-DK\ROT_Provisioning\OEMiROT\..\..\Applications\ROT\OEMiROT_Boot\Binary\OEMiROT_Boot.bin" 0x8000000 -v
      -------------------------------------------------------------------
                       STM32CubeProgrammer v2.21.0                  
      -------------------------------------------------------------------

ST-LINK SN  : 001D00423433510F37363934
ST-LINK FW  : V3J16M8
Board       : STM32H7S78-DK
Voltage     : 3.27V
SWD freq    : 8000 KHz
Connect mode: Hot Plug
Reset mode  : Software 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: OEMiROT_Boot.bin


Memory Programming ...
  File          : OEMiROT_Boot.bin
  Size          : 63.24 KB 
  Address       : 0x08000000


Erasing memory corresponding to segment 0:
Download in Progress:
北北北北北北北北北北北北北北北北北北北北北北北北北 0% 圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹?95%圹?100%

File download complete
Time elapsed during download operation: 00:00:00.309

Verifying...


Read progress:
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Time elapsed during verifying operation: 00:00:00.223


Download verified successfully


OEMiROT_Boot Written
Define write protected area and hide protected area
"C:/Program Files/STMicroelectronics/STM32Cube/STM32CubeProgrammer/bin/STM32_Programmer_CLI.exe" -c port=SWD speed=fast ap=1 mode=Hotplug -obrss 0x5200221c 0x000000ff 0 0x00
      -------------------------------------------------------------------
                       STM32CubeProgrammer v2.21.0                  
      -------------------------------------------------------------------

ST-LINK SN  : 001D00423433510F37363934
ST-LINK FW  : V3J16M8
Board       : STM32H7S78-DK
Voltage     : 3.28V
SWD freq    : 8000 KHz
Connect mode: Hot Plug
Reset mode  : Software 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

Reconnecting...
ST-LINK SN  : 001D00423433510F37363934
ST-LINK FW  : V3J16M8
Board       : STM32H7S78-DK
Voltage     : 3.27V
SWD freq    : 8000 KHz
Connect mode: Hot Plug
Reset mode  : Software reset
Device ID   : 0x485
Revision ID : Rev B
圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹 100%
Set Option Bytes RSS succeeded

"C:/Program Files/STMicroelectronics/STM32Cube/STM32CubeProgrammer/bin/STM32_Programmer_CLI.exe" -c port=SWD speed=fast ap=1 mode=Hotplug -obrss 0x52002234 0x03ff03ff 16711680 0x00
      -------------------------------------------------------------------
                       STM32CubeProgrammer v2.21.0                  
      -------------------------------------------------------------------

ST-LINK SN  : 001D00423433510F37363934
ST-LINK FW  : V3J16M8
Board       : STM32H7S78-DK
Voltage     : 3.27V
SWD freq    : 8000 KHz
Connect mode: Hot Plug
Reset mode  : Software 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

Reconnecting...
ST-LINK SN  : 001D00423433510F37363934
ST-LINK FW  : V3J16M8
Board       : STM32H7S78-DK
Voltage     : 3.28V
SWD freq    : 8000 KHz
Connect mode: Hot Plug
Reset mode  : Software reset
Device ID   : 0x485
Revision ID : Rev B
圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹圹 100%
Set Option Bytes RSS succeeded

Application image programming in download slots
Application image programming in download slots
"C:/Program Files/STMicroelectronics/STM32Cube/STM32CubeProgrammer/bin/STM32_Programmer_CLI.exe" -c port=COM4 br=115200 -elbl C:/Program Files/STMicroelectronics/STM32Cube/STM32CubeProgrammer/bin/ExternalLoader/MX66UW1G45G_STM32H7S78-DK_XSPIM1-SFIx.stldr -d ..\..\Applications\ROT\OEMiROT_Appli\Binary\rot_app_enc_sign.hex --verify
      -------------------------------------------------------------------
                       STM32CubeProgrammer v2.21.0                  
      -------------------------------------------------------------------

Serial Port COM4 is successfully opened.
Port configuration: parity = even, baudrate = 115200, data-bit = 8,                     stop-bit = 1.0, flow-control = off
Activating device: OK
Board       : --
Chip ID: 0x485 
BootLoader protocol version: 4.0
Device name : STM32H7RSxx
Flash size  : 64 KBytes (default)
Device type : MCU
Revision ID : --  
Device CPU  : Cortex-M7

Loading Flashloader..

Flashloader Load done with success

Loading Open Bootloader..


Opening and parsing file: OpenBootloader_STM32H7RS-DK.bin


Memory Programming ...
  File          : OpenBootloader_STM32H7RS-DK.bin
  Size          : 79.62 KB 
  Address       : 0x24030000


Erasing memory corresponding to segment 0:
Not flash Memory : No erase done
Download in Progress:
北北北北北北北北北北北北北北北北北北北北北北北北北 0% ? 2%? 4%? 6%? 8%?10%?12%?14%?16%?18%?20%?22%?24%?26%?28%?30%?32%?34%?36%?38%?40%?42%?44%?46%?48%?50%?52%?54%?56%?58%?60%?62%?64%?66%?68%?70%?72%?74%?76%?78%?80%?82%?84%?86%?88%?90%?92%?94%?96%?98%?100%

File download complete
Time elapsed during download operation: 00:00:08.612

Open Bootloader Load done with success
Serial Port COM4 is successfully opened.
Port configuration: parity = even, baudrate = 115200, data-bit = 8,                     stop-bit = 1.0, flow-control = off
Timeout error occured while waiting for acknowledgement.
Error: Activating device: KO. Please, verify the boot mode configuration and check the serial port configuration. Reset your device then try again... 
Error: Init Open Bootloader operation failed.
 

    1 reply

    Aziz BRIGUI
    Aziz BRIGUI
    ST Technical Moderator
    September 23, 2026

    Hi ​@Kshor,

    Do you encounter the same issue when using the latest STM32CubeProgrammer release (v2.23.0)?

    Aziz

    In order to give better visibility on the answered topics, please click on 'Accept as Solution' on the reply which solved your issue or answered your question.
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