Reflashing firmware in st-link (STM32F103CBT6) in Nucleo board ?

[laurentz]

Hello, my Nucleo-F446RE board just went dead this morning (USB device not recognized anymore).
I only get 4 slow red flashes, then nothing. Device manager in Windows 10 says it cannot get the USB descriptor.

Is it possible to re-flash the ST-Link part (STM32F103CBT6 it seems) to get back the original béhavioral (at least to be able to use the ST-Link upgrader STWS-link007) ?
If so, where to find the binary and how to proceed: I suppose I'll need an external ST-link or Serial programmer and connect to some pins on the board ?

Any hope ?

Best regards,
Laurent

[mark03]

It has been a long time since I did this, but I remember it is possible.  The procedure may be different for different boards.  On mine I needed to change some of the solder jumpers to provide access to the JTAG SWD lines on the ST-Link processor, then use a second dev kit (or something like a J-link) to re-program the part via SWD.  I don't know where to find the ST-Link firmware image but I imagine it is available.  I was flashing the Black Magic Probe firmware on mine.  Maybe google for that to see some examples of the procedure?

[GromBeestje]

You can flash the bootloader, available at https://github.com/Krakenw/Stlink-Bootloaders (be sure to take the correct version v2.0 vs v2.1) via SWD.
Then use the official STLINK upgrade tool to reflash the actual firmware.

[emece67]

.

[laurentz]

Thanks to all for giving me some hope

emece67

Could you explain a bit more which pins I should look after on F446RE board ? I've a spare ST-Link V2 (clone unfortunately) that I could use to reflash the board but I can't figure out where to connect it

[GromBeestje]

See this
http://nuft.github.io/arm/2015/08/24/blackmagic-stlink.html
look at wiring

[laurentz]

Amazing, probably the board was scared by reading the instructions to reflash it, I started testing the continuity of the SWD signals from the connector, and it suddenly is working again.