Flashing firmware with st-link after failed upload [SOLVED]

[mane2]

I recently uploaded binary with web interface to my Tesla SDU, and stm32 board stopped responding. Now I pulled the board out of the motor and got st-link v2 in my hand. I did not find any instructions how to do this for Small DU logic board V4. I need to find where to connect those swdio, swclk, 3.3v and gnd wires. Here’s how the board looks. Also, should I flash boot loader too, or just the stm32-sine.hex ?

[johu]

Didn't your ST Link come with a straight through cable?
On the top row (i.e. where the notch is) pin 4 is SWDIO and pin 5 is SWCLK

You only need to flash the firmware, not the boot loader.

[mane2]

Thanks. Yes. ST-link came with 4 straight through cables.

How about 3.3v and ground? Where to plug those leads?

[mane2]

Found this schematic for SDU V4, but now I'm bit confused. You said top row, but notch is on the bottom and schematics show that lower row pins from left 4 & 5 have same numbers 46 & 49 as that SWPROG port above in pic.

Can you confirm that the pic is correct where I drawed the pins?

Other question is, do I need to supply 3.3v and ground when I have 12v power supply anyways? Or which power supply should I use?

[royhen99]

With 12V supply connected you do not need 3.3V connected but will require a ground connection to the ST-link. The power connections marked are correct but swclk and swdat are reversed, ( should be pin 7 swdat, pin 9 swclk).

This is not a very good schematic as a label has been added for TMS_46 and TMS_49 that does not match the net name so it's not obvious they are connected to swdat and swclk.

[mane2]

Thanks for the info on 12v, 3.3v and ground! I guess I can choose, use either 3.3v or 12v, both will work?

Ah, my bad with picture. Of course that way! Thanks for correcting!

Agree with the schematic labels. Needs some guesswork

[mane2]

Got it flashed! Thanks for your help.

While it was open, also tried to make a stm32-sine build using Debian running on Windows WSL. Got that uploaded via web-interface and that worked too. So all good now!

[johu]

Great