stm32f4: flashing causes board to be ST-link to be locked

[Siri2K]

Hi everyone,

I'm trying to run a simple blinky.rs code on the nucleo-f446re (with stm32f446re chip) using the following commands
cargo run --bin blinky.rs --release
The first time, the cde flashes fine. However, if I try this command a second time, my board shows this error:

The error indicates that the board is locked.

Although I have 2 work arounds, it is still frustrating the board gets locked everytime I use cargo to flash my code.

To reproduce:

1. Connect NUCLEO board to the computer and ensure the computer can detect it
2. Flash the board using cargo run --bin blinky.rs --release
3. Unplug NUCLEO board
4. PLug In NUCLEO board
5. Attempt to flash again with cargo run --bin blinky.rs --release

Workaround 1

1. If OpenOCD is not installed, then enter this command:
   sudo apt -y update sudo apt -y install openocd
2. Copy the reset.txt and change the extension from .txt to .cfg
3. Enter this command:
   openocd -f <path to reset.cfg file>/reset.cfg.
4. If no errors occur, then try cargo run --bin blinky.rs --release again, it should work this time

Note: If at Step 3, there are errors, this workaround will not work as the board is deeply locked. At that point, switch to workaround 2

Workaround 2

1. On the Nucleo board, connect the BOOT0 pin to the 3V3 pin
2. Press the RESET button (black button)
3. Enter this command
   openocd -f interface/stlink.cfg -f target/stm32f4x.cfg

[Siri2K]

I encountered this issue during the tutorial phase. I'm more than happy to take on this problem

[lulf]

Is this an issue with embassy per se? It seems like an issue that should be raised with the probe-rs project.

[Siri2K]

There's a separate repo for probe-rs? If there is, can you post the link, I'll put this issue there

[ypearson]

https://github.com/probe-rs/probe-rs