static void InitMainClockPll(void)
{
CLKSYS_XOSC_Config( OSC_FRQRANGE_2TO9_gc, 0, OSC_XOSCSEL_XTAL_16KCLK_gc );
CLKSYS_Enable( OSC_XOSCEN_bm );
do {} while ( CLKSYS_IsReady( OSC_XOSCRDY_bm ) == 0 );
PORTE.OUTSET = PIN0_bm;
CLKSYS_Main_ClockSource_Select( CLK_SCLKSEL_XOSC_gc );
CLKSYS_Disable( OSC_RC2MEN_bm );
CLKSYS_Disable( OSC_RC32MEN_bm );
}
char system_clocks_init(void)
{
/******************************************************************
* System Clock 32MHz (XOSC Quarz 16MHz, PLL Faktor 2)
******************************************************************/
/* Nach dem Reset ist die Quelle des Systemtaktes der interne
2MHz RC-Oszillator (System Clock Selection: RC2MHz)
*/
// Oszillator XOSC konfigurieren (12..16MHz, 256 clocks startup time)
CLKSYS_XOSC_Config( OSC_FRQRANGE_12TO16_gc,
false,
OSC_XOSCSEL_XTAL_256CLK_gc );
// Oszillator XOSC enable
CLKSYS_Enable( OSC_XOSCEN_bm );
// Warten bis der Oszillator bereit ist
do {} while ( CLKSYS_IsReady( OSC_XOSCRDY_bm ) == 0 );
// PLL source ist XOSC, Multiplikator x2
CLKSYS_PLL_Config( OSC_PLLSRC_XOSC_gc, 2 );
// Enable PLL
CLKSYS_Enable( OSC_PLLEN_bm );
// Prescalers konfigurieren
CLKSYS_Prescalers_Config(CLK_PSADIV_1_gc, CLK_PSBCDIV_1_1_gc );
// Warten bis PLL locked
do {} while ( CLKSYS_IsReady( OSC_PLLRDY_bm ) == 0 );
// Main Clock Source ist Ausgang von PLL
CLKSYS_Main_ClockSource_Select( CLK_SCLKSEL_PLL_gc );
// Nun ist der System Clock 32MHz !
/* Hinweis:
32kHz TOSC kann nicht in Verbindung mit PLL genutzt werden, da
die minimale Eingangsfrequenz des PLLs 400kHz beträgt.
*/
return(1);
} // Sets System Clock to 32MHz
/** \brief Initialize and set cpu and periheral clocks.
*
* CPU clock frequencies set are:
* -CPU: 32HMZ
* -Peripheral Prescaling: NONE */
void setup_clocks(void) {
// set 32MHZ oscillator as CPU clock source
CLKSYS_Enable(OSC_RC32MEN_bm); // enable
do { nop(); } while (!CLKSYS_IsReady(OSC_RC32MRDY_bm)); // wait til stable
CLKSYS_Main_ClockSource_Select(CLK_SCLKSEL_RC32M_gc); // select for CPU
// disable all presacalers, until we decide otherwise
CLKSYS_Prescalers_Config(CLK_PSADIV_1_gc, CLK_PSBCDIV_1_1_gc);
// set up external 32KHz oscillator (NOTE: first param is ignored)
CLKSYS_XOSC_Config(OSC_FRQRANGE_04TO2_gc, false, OSC_XOSCSEL_32KHz_gc);
// set internal 32KHz oscillator as source for DFLL and autocalibrate 32MHz
CLKSYS_Enable(OSC_XOSCEN_bm); //enable
do { nop(); } while (!CLKSYS_IsReady(OSC_XOSCRDY_bm)); // wait til stable
CLKSYS_AutoCalibration_Enable(OSC_RC32MCREF_bm, true); // true == ext 32KHz
// disable unused oscillators (internal 2MHz and 32KHz oscillators)
CLKSYS_Disable(OSC_RC2MEN_bm | OSC_RC32KEN_bm);
}
void InitClock ()
{
/* Clock Setup */
/* Enable for external 2-9 MHz crystal with quick startup time
* (256CLK). Check if it's stable and set it as the PLL input.
*/
CLKSYS_XOSC_Config( OSC_FRQRANGE_2TO9_gc, false, OSC_XOSCSEL_EXTCLK_gc );
CLKSYS_Enable( OSC_XOSCEN_bm );
do {} while ( CLKSYS_IsReady( OSC_XOSCRDY_bm ) == 0 );
/* Configure PLL with the 8 MHz external clock as source and
* multiply by 4 to get 32 MHz PLL clock and enable it. Wait
* for it to be stable and set prescaler C to divide by two
* to set the CPU clock to 16 MHz.
*/
CLKSYS_PLL_Config(OSC_PLLSRC_XOSC_gc, 4 );
CLKSYS_Enable( OSC_PLLEN_bm );
CLKSYS_Prescalers_Config( CLK_PSADIV_1_gc, CLK_PSBCDIV_1_2_gc );
do {} while ( CLKSYS_IsReady( OSC_PLLRDY_bm ) == 0 );
CLKSYS_Main_ClockSource_Select( CLK_SCLKSEL_PLL_gc );
}
