Is there a way to make the RESET pin work in the inverse? Is there a way for me to have this work the opposite way?
I have one cable with an alligator clip hooked up to the reset pin and another hooked up to ground.
When I clip them both together, the board resets.
However, I would like for this to work in the opposite way such that they’re already clipped together and when you detach the cables, the board resets.
My personal preference would be to attach a NOT gate to the RESET pin.  This can be constructed very simply from a single NPN transistor (or N-channel MOSFET) and a resistor.



simulate this circuit &ndash; Schematic created using CircuitLab
With the wire disconnected R1 turns on Q1 which pulls the RESET pin LOW.  With the wire connected Q1 is turned off, allowing RESET to be pulled back up by the pullup resistor that's built into the Arduino.
This method also won't interfere with the programming reset action of the Arduino.