đồng hồ sử dụng ds1307

[thanhdtk6]

mình mới lập trình với pic 16f877a và định làm chiếc đồng hồ sử dung ic ds307 nhưng không hiểu sao nó chạy được 1 lúc thì lại bị đơ ,mọi người giúp mình với
//===========================================
//ten chuong trinh : tao dong ho
//nguoi thuc hien : tdtmt
//ngay thuc hien : 21/4/2012
//dung pic 16f877a ---thach anh 20MHz
//===========================================
#include <16f877a.h> //KHAI BAO THU VIEN PIC16F877A
#device *=16 adc=10 //KHAI BAO CON TRO VA ADC
#FUSES NOWDT, HS, NOPUT, NOPROTECT //THIET LAP CAU HINH CHO PIC
#use delay(clock=20000000) //KHAI BAO TAN SO DAO DONG LA 20MHZ
#use i2c(Master,Slow,sda=PIN_C4,scl=PIN_C3) //BAT CHE DO GIAO TIEP I2C
//=======KHAI BAO DIA CHI CUA CAC CONG=======
#byte PORTA =0x05
#byte PORTB =0x06
#byte PORTC =0x07
#byte PORTD =0x08
#byte PORTE =0X09
//===========================================
#byte TRISA =0x85
#byte TRISB =0x86
#byte TRISC =0x87
#byte TRISD =0x88
#byte TRISE =0x89
//===========================================
//KHAI BAO HANG =============================
#BIT led1 =PORTA.0
#BIT led2 =PORTA.1
#BIT led3 =PORTA.2
#BIT led4 =PORTA.3
#BIT led5 =PORTA.4
#BIT led6 =PORTA.5
//============================================
//KHAI BAO BIEN/////////////////
int8 sec,min,hour,dow,date,month,year,i;
int8 sec1,sec2,min1,min2,hour1,hour2,day,date1,date2,mo nth1,month2,year1,year2;
INT8 CONST led_code[ ]={0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x9 0};
//cac chuong trinh con ///////////////////////
void display();
void convert_bcd();
void update_time();
//============================================
void main()
{
TRISA =0X00;
TRISD =0X00;
TRISC =0X00;
i=0;
while(true)
{
update_time();
convert_bcd();
display();
}
}
void update_time()
{
i2c_start(); //phat bit start I2C
i2c_write(0xD0); //gui dia chi cua slave
i2c_write(0x00); //thiet lap lai con tro - set register pointer
i2c_stop(); //phat bit stop I2C
I2C_start(); //phat bit start I2C
I2C_write(0xD1); //gui lenh doc du lieu
sec = i2c_read(1); //doc du lieu tai dia chi 0x00
min = i2c_read(1); //doc du lieu tai dia chi 0x01
hour = i2c_read(1); //doc du lieu tai dia chi 0x02
dow = i2c_read(1);
date = i2c_read(1);
month = i2c_read(1);
year = i2c_read(0);
i2c_stop(); //phat bit stop I2C
delay_us(100);
}
void convert_bcd()
{
sec1=sec & 0x0F;
sec2=(sec & 0x70)>>4; //convert to BCD SEC
min1=min & 0x0F;
min2=(min & 0x70)>>4; //convert to BCD MIN
hour1=hour & 0x0F;
hour2=(hour & 0x30)>>4; //convert to BCD HOUR
day=(dow & 0x07);
date1=date & 0x0F;
date2=(date & 0x30)>>4; //convert to BCD DATE
month1=month & 0x0F;
month2=(month & 0x10)>>4;//convert to BCD MONTH
year1=year & 0x0F;
year2=(year & 0xF0)>>4; //convert to BCD YEAR
}
void display()
{
do
{
// sec - min - hour
i=i+1;
PortD=led_code[sec1];
led6=0;//SEC1
delay_ms(20);
led6=1;
PortD=led_code[sec2];
led5=0;//SEC2
delay_ms(20);
led5=1;
//=================================
PortD=led_code[min1];
led4=0;//MIN1
delay_ms(20);
led4=1;
PortD=Led_code[min2];
led3=0;//MIN2
delay_ms(20);
led3=1;
//==================================
PortD=led_code[hour1];
led2=0;//HOUR1
delay_ms(20);
led2=1;
PortD=led_code[hour2];
led1=0;
delay_ms(20);
led1=1;
//==================================
}
while(i<=5);
i=0;
}