Need Arduino's clock

[gettingstartedinarduino]

Hi everyone,
We are working on a project where we need the current clock of the Arduino. We have searched and found out that there is a pin in ATMega that is call CLK0, they said that if we put a wire on this one it will take the clock out, but it doesn't. This pin doesn't have anything, it value in the oscilloscope is 0. I also read that it can be done with two arduino together, but how do you connect them and where the clock comes out? If someone could help us we would be very grateful.

Thanks for reading us.

[groundFungus]

What, exactly, does "clock" mean to you? The oscillator that runs the processor? A keeper of time of day?

[gettingstartedinarduino]

The pulses of 16 MHz where the clock takes values of 1 or 0.

[CrossRoads]

You have to change a fuse but to bring the system clock out on the CLK0 pin.
Get yourself a Programmer, this one is $7.77 with free shipping in the US.
Change the needed bit in boards.txt, then Burn Bootloader to change the fuse.

Pololu USB AVR Programmer v2.1

[gettingstartedinarduino]

Thank you so much!
We will try this.

[gettingstartedinarduino]

Hi CrossRoads,
We bought the pololu use avr programmer, we did what you told us but we can't see the clock. Now when we want to load other program in the Arduino it comes out this error: " avrdude: ser_drain(): read error: Device not configured". Do you know what can we do to solve this?
Thank you for reading us!

[CrossRoads]

Did you change the port? There is one port to use it as a Programmer, and another port to use it as a USB/Serial interface.

And then there is the USB port of the Arduino if you are using that.

Worse case, put the fuse back to what it was.