Arduino Due Clock output

Does anybody know how to generate a clock signal on an digital pin of an Arduino Due?

'clock' like in minutes/second, or 'clock' like in serial communication clock , or CPU 'clock', counter clock, etc.... , You should tell us in detail what you want.

ps. there is a seperate Arduino Due group a bit lower down the list.

like a CPU clock. I am trying to communicate to a OV3640 but i have to give it a 24 MHz clock signal. I was wondering if there was a way to generate that using the CPU clock of the Due.