#pragma interrupt_handler timer0_ovf_isr:10
void timer0_ovf_isr(void)
{
TCNT0 = 0xFF; //reload counter value
if((PORTB&0x20)==1){//如果有一个脉冲,就把PORTD=0;
PORTD=0;
}
}
//call this routine to initialise all peripherals
void init_devices(void)
{
//stop errant interrupts until set up
CLI(); //disable all interrupts
port_init();
timer0_init();