STM32H573: system bootloader not responding on I2C4 (blank device)

[obrahimo]

Hi,

I'm trying to program a blank STM32H573 through the embedded system bootloader over I2C4, but the bootloader does not respond.

Setup

• Blank flash, product state Open, BOOT0 = 1 (measured at the MCU pin), board power-cycled
• Host: Aardvark I2C master at 100 kHz, address 0x65 (per AN2606)
• No debugger, USB or UART connected

Result

• Lines idle high, but 0x65 is NACKed
• A full scan from 0x00 to 0x7F gets no ACK

Questions

1. AN2606 lists I2C4 on PD12/PD13. Does the bootloader use only those pins, or also other I2C4 pins such as PB8/PB9?
2. Is BOOT0 = 1 enough on a blank device, or is STiROT involved in this boot path?

Thanks.

[KDJEM.1]

Hello ​@obrahimo ;

 

For STM32H573 , you can activate the I2C4 bootloader with only by PD12/PD13 pins as mentioned in AN2606.

For STiRoT , The embedded STiRoT in the system memory, is programmed by ST during production. STiRoT is the immutable root of trust managing the secure boot and secure install of the first updatable level to execute in a boot sequence. Refer to AN6007 “Getting started with STiRoT (ST immutable Root of Trust) for STM32H5 MCUs” and Security:How to start with STiRoT on STM32H573 - stm32mcu

 

Thank you.

Kaouthar