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Associate
March 17, 2025
Solved

Can't connect to STM32H755 after changing boot option byte

  • March 17, 2025
  • 2 replies
  • 722 views

Hello,

after changing one of the BCM4/7 boot option bytes of my Nucleo STM32H755 board with STM32CubeProgrammer, I can't connect to the MCU any more. When trying to connect with STM32CubeProgrammer, I get

Error: Unable to read device id from ROM table

Error: ST-LINK error (DEV_CONNECT_ERR)

 

Is this related to the change in option bytes or did the board get damaged somehow?

Thanks and regards,

Martin

Best answer by TDK

Try connecting using access port 3 instead of access port 0.

2 replies

TDK
TDKBest answer
Super User
March 17, 2025

Try connecting using access port 3 instead of access port 0.

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mt7883Author
Associate
March 18, 2025

Wow, this works, thanks a lot!

I just double checked: When I turn option BCM7 back on I can connect again on port 0. When I turn BCM7 off I can only connect on port 3.

mƎALLEm
Technical Moderator
March 18, 2025

Hello @mt7883 ,

Read this new article.

"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."