Clock / ATxmega 128A1

Hallo,

This program was produced by the
CodeWizardAVR V2.05.1b Evaluation
Automatic Program Generator




void system_clocks_init(void);


int main(void)
{

system_clocks_init();

while (1)
{

}

 return (0);
}

void system_clocks_init(void)
{
unsigned char n,s;

// Save interrupts enabled/disabled state
s=SREG;
// Disable interrupts
cli();

// External 32,000 kHz clock source on XTAL1 initialization
OSC.XOSCCTRL=OSC_XOSCSEL_EXTCLK_gc;
// Enable the external clock source
OSC.CTRL|=OSC_XOSCEN_bm;

// System Clock prescaler A division factor: 1
// System Clock prescalers B & C division factors: B:1, C:1
// ClkPer4: 32,000 kHz
// ClkPer2: 32,000 kHz
// ClkPer:  32,000 kHz
// ClkCPU:  32,000 kHz
n=(CLK.PSCTRL & (~(CLK_PSADIV_gm | CLK_PSBCDIV1_bm | CLK_PSBCDIV0_bm))) 
|
  CLK_PSADIV_1_gc | CLK_PSBCDIV_1_1_gc;
CCP=CCP_IOREG_gc;
CLK.PSCTRL=n;

// Select the system clock source: External Osc. or Clock
n=(CLK.CTRL & (~CLK_SCLKSEL_gm)) | CLK_SCLKSEL_XOSC_gc;
CCP=CCP_IOREG_gc;
CLK.CTRL=n;

// Disable the unused oscillators: 2 MHz, 32 MHz, internal 32 kHz, PLL
OSC.CTRL&= ~(OSC_RC2MEN_bm | OSC_RC32MEN_bm | OSC_RC32KEN_bm | 
OSC_PLLEN_bm);

// Peripheral Clock output: Disabled
PORTCFG.CLKEVOUT=(PORTCFG.CLKEVOUT & (~PORTCFG_CLKOUT_gm)) | 
PORTCFG_CLKOUT_OFF_gc;

// Restore interrupts enabled/disabled state
SREG=s;
// Restore optimization for size if needed
}

Gruß XMEGA