NUCLEO-H745 + ST-Link Utility = Can not connect to target

[MMatu]

Dear STM Community

I am facing a problem with flashing/erasing STM32H745 microcontroller using STM32-ST Link Utility. Everytime I try to perform any operation I receive popular "Can not connect to target! If you're trying to connect to a low frequency application, please select a lower SWD Frequency...."

So I did that. I went to Target -> Settings. ST-LINK, Serial Number and Firmware of ST-LINK V3 were recognized correctly. I was even able to upgrade the firmware. But setting Mode to Normal or Connect Under Reset or lowering the frequency of SWD is not helping me with connect to, flash or erase the chip. Is there anything I can do to fix this?

[Tesla DeLorean · Accepted solution]

https://community.st.com/s/question/0D50X0000BL7SnASQV/stlink-problems-with-stm32h745idisco

[MMatu]

Thank you Clive for your quick reply. I don't have any goldpins soldered to the board yet so I need to do that first before I check this BOOT0 method but I will get back with some updates ASAP.

[Tesla DeLorean]

ST really needs to jumper BOOT0 on all the dual core boards, most everyone is going to brick the device at some point during debug/development.

Metal tweezers or micro-grippers also work. The BT0 and VDD/GND are conveniently located.

I'd generally recommend a 500ms idle loop in main() prior to calling SystemClock_Config().

Not sure the ST-LINK/V3 supports a connect-under-reset mode currently.

[MMatu]

The solution worked for me. Thank you once again! 🙂

[CGauk]

I used the spring of a bent paper clip to keep a short between the 3V3_VDD and BT0 (BOOT0) holes to cause the Boot into the System ROM. This allows a connect with ST-LINK/V3 and then Erase the Chip to recover a bricked Nucleo-STM32H745. Remove the short after erasing.