I just would like to know how fast the system clock is in default setting. Since the crystal oscillator providing frequency to board is only 4MHZ, i just wonder whether real system clock is 4MHZ.
And if it is, anyone know how can use more than 4MHZ, may be 16MHZ clock speed?
If your board has a 4MHz crystal then the bus /clock speed will be 2MHz (for XEP100). If you want 16MHz clock speed with the same 4MHz crystal , you may use PLL for your application.