STM32U545REI6Q Bootloader GPIO config

[CSmit.4]

AN2606 does a very good job of describing communication peripheral usage by the bootloader, but not so much GPIO pins.Can I get a description of how each of the GPIO pins on the ST32U545REI6Q is configured by the bootloader? This could be important in determining behavior when new chips arrive from the factory and are placed on our custom circuit boards.

Thank you!

 

[Chris21]

AN2606 does describe the pins used, e.g., USART1: specifically pins PA9 and PA10.

I would expect pins not list in the document to be left in the state described by the reset conditions for the microcontroller, as shown in the reference manual.

[TDK]

Pins not used by the bootloader are left in their current state, which after reset is generally high impedance input mode or analog mode depending on the family.