Timer Count , ATmega128, AVR - 3034

 

 Timer Count , ATmega128, AVR 

[ 간략 설명 ]

◈ Timer Count , ATmega128, AVR

◈ 인터럽트 주기

• 1/16us* 256(TCNT0 ) * 1024 = 16.384ms*31cnt 508ms = 0.5sec
• 1/16us * 256분주 * 250TCNT0  = 4ms * 250cnt  = 1sec
  

Timer Count
내용 넣기~~~~

 

 

 ◆◆ ATmega128, Timer Count : T/C 0, LED on/off P.231 ◆◆

0304a_timercount_p231.c

0304A_TimerCount_p231.hex

0304A_TimerCount_p231.prj

---

/*
                  Timer Count   LED on, off      P.231
                  T/C 0  -> LED 0.5sec on,off,  1024분주 사용
                  16Mhz clock : overflow interrupt
                  > 1/16us* 256(TCNT0 ) * 1024 = 16.384ms*31cnt 508ms = 0.5sec
                  0304A_TimerCount_p231.c
*/              

#include <mega128.h>
unsigned char Led = 0xff,  Cnt;

void main(void)
{
                  // 포트 초기화
                  DDRC = 0xff;                              // Port C
                  PORTC = Led;
                  Cnt = 0;                                       // Interrupt 발생 횟수
                 
                  // 인터럽트 초기화
                  TIMSK = 0x01;                          // TOIE0 = 1
                  TCCR0 = 0x07;                           // 프리스케일 = CK/1024
                  TCNT0 = 0x00;                           // 타이머/카운터0 레지스터 초기값
                  SREG = 0x80;                             // 전역 인터럽트 인에이블 비트 I 셋
                 
                  while(1);                                      // 무한루프
}//end main            

interrupt [TIM0_OVF] void Timer_int0(void){
                  // LED on, off
                  Cnt++;
                  if( Cnt == 31 ){
                             Led = Led^0xff;                  // 0xff*0xff =0x00
                             PORTC = Led;
                             Cnt = 0;
                  }//endif
}//endTIM0            

 

---

 

◆◆ ATmega128, Timer Count : T/C 0, LED on/off P.231 ◆◆ 

 

0304B_TimerCount_p232.c

0304B_TimerCount_p232.hex

0304B_TimerCount_p232.prj

 

---

 /*
              Timer Count    T/C 0  > LED on/off         P.232
              T/C overflow interrupt > 1sec > LED on/off
              256분주 사용
              * 인터럽트 주기 = 1/16us * 256분주 * 250TCNT0
                                         = 4ms * 250cnt
                                         = 1sec
              0304B_TimerCount_p232.c
*/                                                    

#include <mega128.h>
unsigned char Led = 0xff, Cnt;

void main(void)
{
                  // 포트 초기화
                  DDRC = 0xff;
                  PORTC = Led;
                  Cnt = 0;
                 
                  //인터럽트 초기화
                  TIMSK = 0x01;
                  TCCR0 = 0x06;
                  TCNT0 = 6;
                  SREG = 0x80;
                 
                  while(1);
}//end main
                              

interrupt [TIM0_OVF] void Timer_int0(void){
                  // LED on/off
                  Cnt++;
                  if( Cnt == 250 ){
                             Led = Led^0xff;
                             PORTC = Led;
                             Cnt = 0;
                  }//endif
                 
}//endTIM0

 

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