I have an Arduino Due and I want to connect the output from the DAC as an input to an Arduino Uno's analog input pin. From this link http://forum.arduino.cc/index.php?topic=164763.0, user DuaneB suggested that a resistor should be used in series with the DAC output to prevent an excessive flow of current that could damage the pin. But he was talking about this when the question was about powering a motor using the current generated from the DAC's voltage.
However, is this series resistor required when simply connecting the output of the pin to the input of another pin? I haven't seen any issue when connecting the output of my Raspberry Pi's GPIO to an arduino's input.