Should Serial (dis)connections reset my Arduino Mega 2560?


I have read at many places, that when making connections/disconnections of Serial, (and Serial1 etc), the Arduino resets.

However, this is not the case for my Sainsmart Arduino Mega 2560 R2 board, and it is actually a nice thing for my project that it doesn’t reset itself each time I open the serial monitor on my PC… It only resets when I upload a new program (hopefully).

I’m just wondering if I have a strange board, or if it’s normal ?

I'm just wondering if I have a strange board,

Yes you have.

Sorry to bump my own topic,

I recently installed Win8.1 64 bits and latest Arduino IDE (1.5.6 R2). And now my Arduino reset itself whenever I open or close the Serial Monitor.

As said in the first post, I didn't have this "problem" with an older IDE and Win7 64 bits.

I would like to know if it's possible to get the old behavior because I prefer when the Arduino doesn't reset whenever I open or close the Serial Monitor...

Any idea ?

Just disable the auto reset circuit. There are a few ways you can do this, like putting a large capacitor on the reset line or breaking the connection between the DTR line and the reset line.

I've just tried on my laptop (Win7) to install IDE 1.0.1 and old driver for Arduino Mega, and the "problem" still occur. I don't understand why it worked before, without doing any modifications to disable the auto reset circuit.

Or maybe I'm just wrong and it always been like this, because it only reset if I open/close Serial Monitor on Serial port 0. Ports 1, 2 and 3 doesn't reset the Arduino. I don't remember exactly the context of the first post so... Forget it :wink: