While the Arduino family of boards connect to your computer using a USB virtual serial port, the ATmega ones have an actual serial connection on-board.

His code is available for download from his site, and works perfectly in the Arduino IDE. The whole thing consists of some simple, easily ported code to implement a bare minimum bit-banged serial ...

You can read the state of a button using Arduino and a few lines of code. The actual state is shown in the Serial Monitor window as 0 or 1, 0 meaning the ...