Preventing reset on serial monitor connect?

Question

Is there a way of preventing the reset when starting the serial monitor in the Arduino IDE?

Answer 1

For the Uno, connect a 10μF capacitor between the reset and ground pins.

For other Arduinos, a 120 Ohm resistor (or equivalent resistance made up of multiple resistors, since 120 Ohms is quite rare on its own) between the 5V and Reset pins should do the trick.

Answer 2

The arduino Playground site has a quite detailed breakdown of different methods of preventing your arduino from restarting, with a bit of background and explanation.

http://playground.arduino.cc/Main/DisablingAutoResetOnSerialConnection

Answer 3

If you would connect a Windows PC, This rudimentary Powershell script works (tested on Arduino Mega):

$port = new-Object System.IO.Ports.SerialPort COM8,9600,None,8,one
$port.DtrEnable = $false
$port.open()
while ($true) {
	$nChar = $port.BytesToRead
	if ($nChar -gt 0) {Write-Host -NoNewline $port.ReadExisting()}
}