NUCLEO-G071RB catch 22 - PA14 set to GPIO input

pdornier1 · ‎2025-11-06

I flashed firmware that sets. Now STM32Cubeprogrammer refuses to connect to the STLINK portion.

How to recover from this / debrick the boards ? I tried pulling up PA14 / boot0 pin with a pull-up to CN7 pin 7, but no such luck...

Andrew Neil · ‎2025-11-06

Having the ST-Link connect under hardware reset should do it.

A complex system that works is invariably found to have evolved from a simple system that worked.
A complex system designed from scratch never works and cannot be patched up to make it work.

pdornier1 · ‎2025-11-06

Nope...

12:42:17 : UR connection mode is defined with the HWrst reset mode
12:42:22 : UR connection mode is defined with the HWrst reset mode
12:42:22 : ST-LINK error (DEV_USB_COMM_ERR)
12:42:22 : Error: Problem occured while trying to connect

Serial console through STLINK _is_ working, and shows my startup message, so the USB connection is good.

TDK · ‎2025-11-06

Hold reset, click connect, then release reset. You may have to play around a bit to get the timing exactly right. STM32CubeProgrammer needs to connect after NRST is high but before PA14 is reassigned. How quick this happens depends on your program.

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Andrew Neil · ‎2025-11-06

@TDK wrote:
STM32CubeProgrammer needs to connect after NRST is high but before PA14 is reassigned. How quick this happens depends on your program.

@pdornier1 so it's a good idea to have a delay in there - to give time for a debugger or programmer to connect...

A complex system that works is invariably found to have evolved from a simple system that worked.
A complex system designed from scratch never works and cannot be patched up to make it work.