STM32F427IIT6 not responding to boot0 pin, runs previously uploaded program, will not connect to STLink

[SSche.4]

Previously, code was repeatedly able to be uploaded and executed following normal operation of the STLink and boot0 pin. However, after a possibly broken peripheral was connected to a separate unit which itself was connected to the board with the STM32F4 on it, said board/microcontroller no longer responds to boot0 high or low. Whenever the ST Link V2 was used to try to connect to the microcontroller, it returned a "No device found on target" error or similar. This was attempted on 3 pieces of software - STM32CubeIDE, STM32CubeProgrammer, and ST-Link Utility.

When powered on, the board still executes the last program uplaoded to it - the two LEDs on the board still flash correctly according to the previously installed program. There is no obvious physical damage to the board, and nothing was smelled during the event.

So far, different ST-Links, different power supplies, different USB cables, different startup sequences, different firmwares, different power interfaces, and different computers have been used, with no difference. Compressed air and light percussive disruption have been used to try to clear any possible pin obstructions.

My best guess is that either something got misconfigured somewhere, or that there is a hardware failure somewhere between the pin connecter and the microcontroller. Both are at the moment beyond my experience. Due to lack of connecters, no attempt has been made to communicate with the unit through other means than the STLink.

Any thoughts on what to attempt next, or what to be on the lookout for as far as hardware failures go? I am very new to working with STM and microcontrollers in general, if more information is needed I will do my best to provide it.

[Tesla DeLorean]

Destruction can happen instantaneously and doesn't necessarily result in smoke or smell.

Core shouldn't need BOOT0 at any specific state unless the user code powers down the internal hardware that the debugger is trying to communicate.

That it runs your code rather than the System Boot Loader whatever BOOT0 state, probably that pin isn't working.

Voltage at power pins and VCAP pins?

You got more than one board?

You able to remove and replace the MCU?

[SSche.4]

Thank you for your assistance. Voltage at power pins is normal, VCAP_1 reads 1.13V, and VCAP_2 reads nothing (although from what I have read, only one needs to be connected I think, so that is likely normal). This implies some things about the power regulator settings that I will look into.

Unfortunately, we do not have another board. Replacing the MCU is probably not an option .