I2C bootloader is not responding on NUCLEO-G031K8 board

[MMisa]

I succesfully use I2c slave mode on address 0x52 in my application.

I can get into bootloader via software by rebooting and in early state remapping SYSCFG_MEMRM = 0x1.

But in bootloader, I2C on pins PB6 and PB7 is not responding to address 0x51 - (stm32flash posts "responding Failed to send command"), as for other random - not used - I2C addresses .

I can use succesfully serial bootloader (I am using patched stm32flash) on pins PA9,PA10 (USART1), so I suppose I am getting bootloader mode correctly. PA3 pin od USART2 is high, so I hope I am not affected with problem "stuck in USART2 detection" described in AN2606.

If I would try stm32flash on I2C in running state (not bootloader) on address 0x52, it will respond with Unexpected reply from device on command 0x01 (which is normal, because it is my application running, not bootloader).

I have tried also to use the same address as bootloader (0x51) in my application, but also no luck.

Please give me any advice what I should try more.

Finally I want to use STM32G030K8T6 processor on my custom board and I really need to use I2C bootloader.

Is anybody using I2C bootloader on NUCLEO-G031K8 board or other STM32G03x succesfully?

[MMisa]

I have also checked the NUCLEO-G031K8 board schematics, but no interference or pin problem is present.

[MMisa]

Still no luck,

now we are using STM32G030K8T6 MCU on custom board and problem still persist. I can upload firmware only via USART1, i2c is dead / not responding in bootloader. I tried also lower I2C clock but no luck.

Can somebody from ST look at it?

here https://community.st.com/s/question/0D53W0000093IXeSAM/stm32g030f6-i2c-bootloader-not-working-no-ack

is similar (if not the same) problem.

[MMisa · Accepted solution]

It seems that is wrong i2c address in the manual - it should be not 0x51, but 0x56. Now I can succesfully detect CPU with the stm32flash software.