Did I broke my STM32?

[Simsalabim]

Hello together,

I just tried to get my STM32F407-Discovery working. I wanted to upload the firmware by putting it into DFU Mode, connecting it via USB to my computer and using CubeProgrammer to upload the code into the STM32s memory. So I connected BOOT0 to VDD and PA9 to GND. Unfortunally CubeProgrammer didnt recognized the board. And yes, I'm 100% sure, that the cable can transfer Data and works properly. Pressing the restart button didnt change anything. Only LD7 and the Power LED were turned on.

10min later I plug the USB Cable again in into my PC to power the board but now it doesn't turn on at all. There is not a single LED turned on. I have to say that I have two STM32F407-Discovery board and both seem to be dead. Does anyone have an Idea how I could have broken both of them just by powering them via micro USB and doing some wiring? Or a suggestion of how I can verify that they are definitely broken. My theory is, that I connected the 5V Pin accidentally to a different PIN than BOOT0 what caused a short circuit ad broke the board. Is that possible?

[waclawek.jan]

Connecting the miniUSB (i.e. STLink) to PC works?

> PA9 to GND

I don't think that's OK.

JW

[TDK · Accepted solution]

If you're connected to LD1, and no LEDs come on, the board is probably dead.

Pulling up BOOT0 is not necessary to program the board in the majority of cases. The SWD connection is active when a program is being run.

Probing voltages on the board and seeing if 5V is present, and if 3.3V is present, would likely confirm if there are issues.

[BarryWhit]

---

Pulling up BOOT0 is not necessary to program the board in the majority of cases. The SWD connection is active when a program is being run. 

OP says he was trying to use DFU (i.e. bootloader via USB) to program device. Pulling up BOOT0 during reset is the standard way of activating the bootloader.