I tried preventing my Arduino Mega 2560 from restarting every time I open the serial monitor. This link didn't work for me at all.

I tried connecting the RESET pin to 3.3v pin via a 60 ohm resistor and it worked for me. The question is: If I leave that resistor permanently connected, will this solution damage my board as time passes?

  • 2
    Personally I use a large capacitor between reset and ground. 22uF or greater should do it.
    – Majenko
    Dec 16 '17 at 10:28
  • You should connect the resistor to 5V instead of 3.3V. There is no way you can damage the Arduino with this resistor, since the reset pin is pulled low by the USB-to-Serial chip through a (100nF) capacitor. So current can only flow for a tiny moment.
    – Gerben
    Dec 16 '17 at 14:34
  • i already tried 5v with a 120ohm resistor but didn't work
    – Safa Seed
    Dec 16 '17 at 15:49

A 22uF cap between reset and ground does work on my Mega 2560 - opening the serial monitor will not restart the program. However, the Mega is then not downloadable. Therefore, I grounded the cap thru a normally closed relay and connected its control to a digital output. I normally operate with the relay closed. When I want to download a new program I open the relay first. It works great :-)

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