Hi, I bought a NUCLEO-H7A3ZI-Q, and I updated the firmware, from that on, I cant connect to the target whatever I do.

[SLori.2]

The port is showing in device manager and I can update/downgrade the firmware but I cant flash it. I had some similar problem with a bluepill but I put BOOT0 on 1 and erased the chip. After that it worked. I did the same with this board but it tells me cant connect to the target. I tried also with connect under reset. Nothing works...

[Tesla DeLorean]

Don't use ST-LINK Utilities, want to be using STM32 Cube Programmer

If you get the LDO/SMPS settings messed up I'd suggest the following methodology for H7's

Put a jumper on board so you can pull/drive BOOT0 high. The NUCLEO-144's have VDD/BOOT0 pins next to each other to help facilitate.

With the jumper on power cycle the board a couple of time, complete disconnect USB, and reattach, do this twice counting out 5 seconds at each step.

Then when finally reconnected use STM32 Cube Programmer to Erase chip.

Remove jumper

Fix your code

Proceed

[SLori.2]

you are god, I will call you master Tesla DeLorean from now on. Jesus, I never thought to disconnect and reattach the board. Also yes, using ST LINK utilities was a mistake, thank you so much!

8)

[Tesla DeLorean]

The H7's in particular only latch options on power-up, the NRST is not a complete reset in the manner most expect. I think this is to help protect against glitching type attacks., or general robustness of the code protection methods, keys, etc.

I experienced this very early on, I had just received an engineering sample of the H747-DISCO, and promptly bricked it with some "hello world!" type code ported from the NUCLEO-H743 testing prior. The BOOT0 signal was some 0402 pad next to a BGA, and I told ST they needed a jumper or switch, because bricking them is almost a certainty.