MQTT with Arduino Nano + NodeRed

OK, in this case I re-form my question:

What's the most stable and universal way to connect to an Arduino Nano via USB?

By "stable" I mean:

  • it should handle Xon/Xoff buffer overflow control
  • parity check
  • auto reconnection
  • port releasing

I have 25+ years of experience with serial com. and I've learned without these things it's causing many troubles. And there are many cases even on this forum too to show I'm right, like here:

I'd like to avoid cases like that.