Interrupt am Xmega256A3BU wird nicht aktiviert

#include <asf.h>

void clock_init(void);

void timer_init(void);

void clock_init (void)  // scheint zu funktionieren

{

  OSC.CTRL |= OSC_RC32MEN_bm;

  while(!(OSC.STATUS & OSC_RC32MRDY_bm));

  CCP = CCP_IOREG_gc;

  CLK.CTRL = CLK_SCLKSEL_RC32M_gc;

}

void timer_init(void){

PORTCFG.CLKEVOUT = PORTCFG_CLKOUT_PD7_gc;    // Clockoutput an PD7! funktioniert!

TCD0.PER = 4095;

TCD0.CTRLA = TC_CLKSEL_DIV1_gc;

TCD0.CTRLB = TC_WGMODE_SINGLESLOPE_gc;

TCD0.INTCTRLA = TC_OVFINTLVL_HI_gc;

  PMIC.CTRL = PMIC_HILVLEN_bm;

    sei();  

}

int main (void)

{

  board_init();

  clock_init();

  timer_init();

while(1){};

}

ISR (TCD0_OVF_vect)

{

  PORTB.OUTSET = PIN1_bm

  PORTB.OUTCLR = PIN1_bm;      

}