How do I use the clock output on atmega328p?

Forum 2005-2010 (read only) Hardware Interfacing
6

Each timer is able to directly manipulate up to two output pins. I suggest you configure Timer 1 or Timer 2 to toggle an output pin at 1 MHz. The datasheet and this should help...

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1289879390