oscillator wiring with arduino (overclocking)

So i want to overclock my atmega644 running the sanguino software (arduino compatible) . the atmega644 runs on 20Mhz , i want it to run on 27Mhz . i know that's possible , because the uzebox wich is based on an atm644 is overclocked at 28.6.. mhz now i dont want to use a 2 pin crystal , i want to use a 4 pin oscillator (27mhz) so all i need is to know how can i wire the oscillator in the place of the 2 pin crystal (the 20mhz one) and that's it . i can do the fuses and the software part on my own (to get it to work with the new frequency)

Hi, Look up the data sheets for the IC and it should tell you all the different variations on clock options, including using a Oscillator Block.

Tom... :)

thank you TOM :) found it there . it says you should wire the clock_out to the XTAL1 pin and leave XTAL2 pin NC .

karma given .

OSH Park still charges $17 for a 96 MHz overclocked Teensy 3.1.

Those are Arduino compatible too.

amine2:
So i want to overclock my atmega644 running the sanguino software (arduino compatible) .
the atmega644 runs on 20Mhz , i want it to run on 27Mhz .
i know that’s possible , because the uzebox wich is based on an atm644 is overclocked at 28.6… mhz
now i dont want to use a 2 pin crystal , i want to use a 4 pin oscillator (27mhz)
so all i need is to know how can i wire the oscillator in the place of the 2 pin crystal (the 20mhz one)
and that’s it . i can do the fuses and the software part on my own (to get it to work with the new frequency)

Why don’t you want to use a 2 pin crystal? I mod all of my Arduino boards to run at 22.1184 MHz with a tiny 2 pin SMD crystal (this one is on a MEGA R3 board):

(click pic for full size)
crystal.jpg

If you use a 4 pin OSCILLATOR, you’ll need to provide it with +5 and gnd. And a 4 pin CRYSTAL (with two diagonal pins as the crystal and the other two as GND or N/C) won’t fit nicely in place of the original resonator.