STM32WBA5MMG: What happens when BOOT0 is high?

Hariom · ‎2026-01-19

Split from STM32WBA5MMGH6TR Debug interface PCB layout - which is a separate question.

Hi , thank you very much.

In my module (STM32WBA5MMGH6TRTR), there is only one pin for boot selection BOOT0. I believe when it is pulled low booting happens from main flash memory. But when it is high , from where the module is booting.

Andrew Neil · ‎2026-01-19

If your previous question is answered, please mark the solution in that thread.

The STM32WBA5MMG module contains a STM32WBA55UG wireless microcontroller.

You need to look at the microcontroller datasheet for the behaviour of the BOOT0 pin:

https://www.st.com/resource/en/datasheet/stm32wba55ug.pdf#page=22

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