I was just trying to avoid having to have a pair of resistors similar to the serial pin. It is okay to drive LOW (ground) on the reset pin, but NOT okay to drive HIGH (+5V) on that pin.

Since the Arduino has an internal pull-up resistor available (INPUT_PULLUP), I used that instead of "HIGH". A pull-up is just a suitable resistor (eg. 50-100K-ohm) connected between the pin and +5V internally. It would still give +5V for a very weak current draw, but won't pass enough current to harm stuff.

When the pin is later programmed to plain "INPUT", it actually has a very very weak pull-down (to ground) resistance.

So the simple code I supplied just puts a high pulse onto the reset pin for a few hundred milliseconds, and then pulls the pin down to ground and leaves it there.

Safe so long as one never drives HIGH on that pin.

Cheers