Access to the port 'COM4' is denied

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Hello,

Thanks for your answer.

@Alan.Webb

The issue happens on more than one device and under heavy load so I would be looking at power issues rather than port issues personally, but definitely not exclusively. Have you any poor connections anywhere?

As it’s happen on two different device, I also think it come from the board.
I will make mesurement on the output on LM2596 with a multimeter as first test (and also test the tips on bluetooth and ports).

But don’t when: for the moment I’m confined in Paris and I cannot go to my father farm.
I take advantage of this setback to build a PCBv2 as a replacement of my prototype board that should, I hope, solve this problem (luckily the deliveries aren’t suspended).

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