No device found on target

[fontanella]

Hi, I mistakenly used the pin for swd on my F446RE for other purposes and now it does not connect through st link.

Can anyone guide me through a solution for it? The only thing I can do now is update the board. The two leds are always red.

[TDK]

What board?

If NRST is connected, Select Mode: Under reset and Reset mode: Hardware reset in STM32CubeProgrammer. Then connect and erase the flash to recover the chip. These options are also in STM32CubeIDE in the run/debug configuration.

 

[fontanella]

The problem is it does not connect, so i cant erase it

[fontanella]

also, how do i check if nrst is connected? Thanks for helping

 

[TDK]

Did you do what I suggested? What happened? If it did not work, show relevant logs and error messages.

[fontanella]

here is the message that appears

[TDK]

Hmm, If I recreate this issue (reassign SWD pins), I can connect to a Nucleo-64 board with these settings. If that is the only issue, I don't know why would be seeing different behavior. I assume you haven't modified the jumpers or solder bridges on the board at all?

[fontanella]

No modifications at all. I searched and some websites told to reset using the boot pin but I don't know how to do it properly. It said to connect boot to 3.3v pin and then hold reset and then try to connect.

Hi! It sounds like the SWD pins on your F446RE got messed up. If your board only shows red LEDs and ST-Link won’t connect, you might need to use bootloader mode to recover it. Try these steps:

1. Put the board in bootloader mode:

   • Press and hold the BOOT0 button.

   • While holding it, press RESET, then release RESET first, then BOOT0.

2. Connect via USB: Your PC should now see it as a USB device.

3. Use STM32CubeProgrammer:

   • Open STM32CubeProgrammer.

   • Choose USB connection.

   • Try to erase the chip and reprogram your firmware.

4. Reset BOOT0 to 0 after programming.

This should fix the board. If not, the SWD pins may be damaged, and you might need pinterest download another programmer or an external ST-Link.