STM32F4 Discovery stops connecting via ST-LINK with my end-of-degree project

[ReIvAj501]

I'm working on my end-of-degree project using an STM32F407 Discovery board. I have been working with it the last couple of months with no problems, doing the pin configuration with STM32CubeMX and developing the program in ARM Keil uVision 5.

Yesterday, while doing some debugging the board stopped being recognized by the program. When trying to load any program Keil says "No ST-LINK detected", 30 seconds before it worked perfectly.

After looking on the internet this is what I have been able to find.

• The microcontroller part of the board seems to work correctly, being able to run the last program I loaded. This includes among other things an LCD display, using the micro USB as a COM PORT and reading an ADC showing the reading on both the LCD and the COM PORT. This makes me believe that the problem must with the ST-LINK, while the microcontroller is working correctly and the board is properly powered and voltages at all the pins are ok.
• Other than that the board shows LEDs LD2 and LD8 lighted ON and COM LD1 lighted up Red.

• From the computer (Windows 10) I can see the board on the device manager and it is recognized as ST-LINK. If I access the board from windows there is a text document named FAIL.txt that contains the message: "The interface firmware FAILED to reset/halt the target MCU".

• From ST-LINK Utility I am able to connect with the board for a firmware update, but unable to connect to target afterwards, showing the message: "Can not connect to target! If you're trying to connect to a low freqyency application, please select a lower SWD Frecuency mode from Target->Settings menu." When trying to use Automatic Mode it stops at the message: "Waiting for device Nº 1...".

Any help would be appreciated; I have reached to a blocking point and cannot go on with my project. 

Thanks.

[ReIvAj501]

I'm glad to hear that you found a workaround, but unfortunately that's not my case. I didn't update my firmware recently, maybe in April when I bought it, and I have mine connected directly at the laptop's USB port. I tried connecting it to one of the other ports but it had no effect.

[ReIvAj501 · Accepted solution]

At this point I give up on fixing the board.

In retrospective I believe that the cause of the damage might have been a connection I did between one of the GPIOs and one of the power supplies of the project (an ETX power supply). I did that connection to have an interruption to stop the program if that power supply stops working, but I guess it might have broken the board.

[jab_el]

Hello, I have a very similar problem to yours. I'm also working on an end-of-studies project using a STEVAL-BFA001V2B. When I tried to test it for the first time, I powered up the sensor node with an 18V voltage from a controlled power supply. However, when I configured the terminal to start receiving data from the sensor node, I noticed that there was a disk containing the files FAIL.txt, DETAILS.txt, and GETSTARTED.html, but I couldn't see any current consumption on the power supply screen. Could the issue be an electrical defect with the node or just a software configuration problem?

Thank you.