I have a D21G who does not get much farther than its startup, since the code within has a problem. It stays in limbo there, not being able to get to the end of its first loop. The problem is : its USB comm port is stuck too (he is not identified as anything on the USB port, which works perfectly with another D21G I have).
I have tried pressing the reset button during loading : no way. Holding the reset button during powering up (works with some arduinos) : no more success. Loading an empty sketch and holding the reset during loading ...
Is there any known way just to erase the whole memory of the thing so I would start from some firm base ?
Any idea welcome (nothing too esoteric, an no axe wielding, please)
Please try double tapping the reset button on the back of the topboard, the backlight should continue to blink and the serial port should appear. Then upload a very simple sketch such as Blink, it should restore your board.
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