I am currently using the STM32F769I-EVAL MB1219 Rev B board. I wanted to boot the MCU in the DFU bootloader mode, and as the manual suggests I removed the 0 Ohm resistor R124. I also set SW1 to `1`.
This looks like activated the DFU bootloader since it activates some traffic on the USB bus, but the board does not enumerate properly and appears as unknown USB device on my PC.
Reading the options bytes, which should be fine, I got:
Could you please suggest a workaround to overcome the USB enumeration problem? probably I am missed something?