/ 2006.4.2.
// TCT 모드에서 Timer/Counter1 로 1msec만들기
// CodeVisionAVR

// ATMega8L
// 8MHz System Clock
// 8 Prescaler
// OCR = 100

#include <mega8.h>
unsigned char flag; 
unsigned int count;
interrupt [TIM1_COMPA] void timer1_compa_isr(void){    // 1초당 인터럽트 발생
        count++;
}

void Init_Register(void) {
        DDRD= 0xFF;
        PORTD= 0x00;             
       
        TCCR1A=0x00;
        TCCR1B= 0x0A;                   // 0000 1010 // CTC mode(4)  프리스케일러 8
       
        OCR1AH=(100 >> 8);             
        OCR1AL=100 & 0xFF;              // 0000 0000 0110 0100   
        TIFR = 0x40;

        TCNT1H= 0x00;           
        TCNT1L= 0x00;
        TIMSK= 0x10;                    // 0001 0000 // Timer/Counter1, Output Compare A Match Interrupt Enable
           
}

void main(void){
        flag = 0;
        count = 0;
        Init_Register();
        #asm("sei");  
        while(1){
                if(count == 10000){
                        if(flag){
                                PORTD = 0x00;
                                flag = 0;
                                count = 0;
                                TCNT1H= 0x00;           
                                TCNT1L= 0x00;
                        }else{
                                PORTD = 0xFF;
                                flag = 1;
                                count = 0;              
                                TCNT1H= 0x00;           
                                TCNT1L= 0x00;
                        }
                }
        }