can not debug and program STM32H7B0VBT6 - STM32 ST-LINK Utility Says: " Can not connect to the target!. Unexpected error"

[SEMad]

Hi.

I designed a custom board for STM32H7B0VBT6... But in first test ST-LINK Utility (and obviously other tools) Can not connect to the MCU.

the design is correct, soldering have no error, and the ST-Link firmware version already upgraded to V2-1.

I tried many time in all three mode with different clock speeds... but always same error:

 

It is noteworthy that the ST-LINK Utility even can identify the MCU:

 

I am using SWD mode with 4 (VDD, GND, SWCLK, SWDIO) wires.

how can I solve this?

thanks.

[Tesla DeLorean · Accepted solution]

>>how can I solve this?

Stop using ST-LINK Utilities, this tool has been deprecated for several years

Use STM32 Cube Programmer

https://www.st.com/en/development-tools/stm32cubeprog.html

[Piranha]

Connection mode: Under reset

Reset mode: Hardware

[Andrew Neil]

@SEMad​ "I am using SWD mode with 4 (VDD, GND, SWCLK, SWDIO) wires."

Wot - no RESET ?

[Piranha]

Indeed. Then without NRST line the reset mode should be set to "software".

[Andrew Neil]

and without the NRST line, you won't be able to use hardware reset - eg, if software disables the SWD lines...

[SEMad]

thanks.

worked perfectly.

[SEMad]

I designed many many board without accessing RST pin in debugging.

you can pull up BOOT0 when software disables the SWD lines...