ATmega128 - DS1302 RTC(Real Time Clock) 동작 소스.

#define dir_flow_set DDRC

#define out_flow_pin PORTC

#define in_flow_pin PINC

#define data_out_set (dir_flow_set=0xFF, out_flow_pin=0xFB)

#define data_in_set (dir_flow_set=0xFD)

#define ds1302_reg_second (0x80)

#define ds1302_reg_minute (0x82)

#define ds1302_reg_hour (0x84)

#define ds1302_reg_date (0x86)

#define ds1302_reg_month (0x88)

#define ds1302_reg_day (0x8a)

#define ds1302_reg_year (0x8c)

#define ds1302_reg_ctrl (0x8e)

#define ds1302_reg_trickle_charger (0x90)

#define ds1302_reg_clock_burst (0xbe)

unsigned char check_am_pm=0;

unsigned char hour_data[3]={0}, minute_data[3]={0}, second_data[3]={0};

unsigned char date_data[3]={0}, month_data[3]={0};

unsigned char day_data[3]={0}, year_data[3]={0};

unsigned char get_hour=0, get_minute=0, get_second=0;

unsigned char get_date=0, get_month=0;

unsigned char get_day=0, get_year=0;

/* ----- Pin Assignment : PORT0 = /RST, PORT1 = I/O, PORT2 = SCLK ----- */

void ds1302_write(unsigned char Instruction, unsigned char Data) {

 unsigned char i;

 data_out_set; _delay_us(2);

 for(i=0; i<8; i++) {

  if((Instruction & 0x01)) out_flow_pin|=0x02;

  else out_flow_pin&=0xFD;

  out_flow_pin|=0x04; Instruction>>=1; out_flow_pin&=0xFB;

 }

 for(i=0; i<8; i++) {

  if((Data & 0x01)) out_flow_pin|=0x02;

  else out_flow_pin&=0xFD;

  out_flow_pin|=0x04; Data>>=1; out_flow_pin&=0xFB;

 }

 _delay_us(1); out_flow_pin = 0xFA;

}

unsigned char ds1302_read(unsigned char Instruction) {

 unsigned char i, Data = 0;

 data_out_set; Instruction |= 0x01; _delay_us(2);

 for(i=0; i<8; i++) {

  if((Instruction & 0x01)) out_flow_pin|=0x02;

  else out_flow_pin&=0xFD; out_flow_pin|=0x04;

  Instruction>>=1; out_flow_pin&=0xFB;

 }

 data_in_set;

 for(i=0; i<8; i++) {

  Data>>=1;

  if((in_flow_pin & 0x02) != 0) Data|=0x80;

  out_flow_pin|=0x04; out_flow_pin&=0xFB;

 }

 _delay_us(1); out_flow_pin=0xFA; return Data;

}

/* -------------------- 사용자 정의 함수 -------------------- */

void ds1302_get_time(void) {

 get_second=ds1302_read(ds1302_reg_second);

/* if((get_second&0x80)==0x80) {

  get_second&=0x7F;

  ds1302_write(ds1302_reg_second, get_second);

 }*/

 get_minute=ds1302_read(ds1302_reg_minute);

 get_hour=ds1302_read(ds1302_reg_hour);

 if(!(get_hour & 0x20)) check_am_pm=0;

 else check_am_pm=1;

 second_data[0]=((get_second>>4)&0x0F)+'0';

 second_data[1]=(get_second & 0x0F)+'0';

 minute_data[0]=((get_minute>>4)&0x0F)+'0';

 minute_data[1]=(get_minute & 0x0F)+'0';

 hour_data[0]=(((get_hour&0x1F)>>4)&0x0F)+'0';

 hour_data[1]=((get_hour&0x1F)&0x0F)+'0';

}

void ds1302_get_calendar(void){

 get_date=ds1302_read(ds1302_reg_date);

 get_month=ds1302_read(ds1302_reg_month);

 get_day=ds1302_read(ds1302_reg_day);

 get_year=ds1302_read(ds1302_reg_year);

 date_data[0]=((get_date>>4)&0x0F)+'0';

 date_data[1]=(get_date & 0x0F)+'0';

 month_data[0]=((get_month>>4)&0x0F)+'0';

 month_data[1]=(get_month & 0x0F)+'0';

 day_data[1]=(get_day & 0x0F)+'0';

 year_data[0]=((get_year>>4)&0x0F)+'0';

 year_data[1]=(get_year & 0x0F)+'0';

}