Hi, I probably made a big mistake:
usinf repetier firmware V1.0.3 on a rumba board and repetier server on a raspberry Pi.
For BLTouch I did some firmwar changes and transferred from laptop via USB cable. Everything worked fine.
No I found in repetier server the possibility to perform firmware updates.
Compiled in arduino environment and exported. Two files were created , one without and one with bootloader.
By mistake i chose the one with bootloader.
The detail windows shows many "stk500v2_ReceiveMessage(): timeout".
since then I am not able to communicate with the rumba board.
I tried many hours to find a solution with
- putting the board in DFU mode
- Atmel Flip driver in win10 - faile due to missing certification
- Flip driver in a virtual Win XP - failed for incompatible driver
- Flip driver in a virtual Win7 - could be installed
 Now I have an Atmel USB device with ATmega16u2 in device manager - I was hopeful.
 But flip could not open USB device.
I was printing face shield for MakervsVirus, but this is now stopped.
So I would be happy about any advice how to bring my rumba board back to live.
programmer - buy new rumba - buy another board?
And despite this: happy eastern and stay healthy!