I have a Matek F405-WMN and I cannot get it to go into DFU mode. This happened after I installed Ardupilot on it. The board went into DFU mode easily and I was able to flash the arduplane_with_bl.hex file but now when I press the DFU button and plug in my USB cable the board always boots right into Arduplane. Has anyone had problems getting their boards to go back onto DFU mode after flashing Arduplane?
FAQs and user guide – Matek Systems // Red/Blue/Green LEDs light up/blink normal when FC booting, but FC can‘t connect to configurator, or can’t go into DFU mode.//