#include <iom128.h>
extern void delay_1ms() ;
void port_init(void)
{
  DDRB  |= (1<<5);    //initialize PORTB5's direction out
  PORTB |= (1<<5);    //initialize PORTB5's voltage high
}
/******************************** void delay_nms *********************************/
void delay_nms(int n)
{
  unsigned int j;
  for (j=0;j<n;j++)
  delay_1ms();
}
/******************************* led_flash **************************************/
void led_flash()
{
     port_init();
     for(;;)
     {
        PORTB^=0x20;
        delay_nms(300);
     }
}