Đồng hồ số dùng DS1307

[HueDN]

Đây là code của đồng hồ 6 digit của TMdùng để học tập. Tuy nhiên vì mới học PIC nên chưa hiểu được. Nhất là chổ MAP đó. Các cao thủ giải thích dùm nhé

/****************************************************************   
* Real time Clock DS1307 
* Dong ho so su dung DS1307 hien thi tren 6 LED 7-segment hh.mm.ss
* Sofware: Compiler CCS Ver 4.018
* Harware: TMe - EasyPIC: (www.tme.com.vn)
   - Pull up PORTD, Pull-down Switches, connect PORTD to Switches
   - Switches: T1 - Mode, T2 - set time, T3 - clean status
   - DIP Swich SW2 all ON (Enable 7-segment and RTC DS1307)
*****************************************************************/

#include <16F877A.h>
#include <def_877a.h> //file header do nguoi dung dinh nghia
#include <ds1307.c>
#fuses   HS,NOWDT,NOPROTECT,NOLVP
#use     delay(clock=12000000)

byte sec,min,hour;
byte const MAP[10] = {0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90};//Cathode
byte DIS1,DIS2,DIS3,DIS4,DIS5,DIS6;
byte key,mode;
int1 ampm,blink,blink_sec,blink_min,blink_hour;
int1 on_off;
int16 count;

#bit SW1   = 0x8.0  // D0 - mode
#bit SW2   = 0x8.1  // D1 - set_time 
#bit SW3   = 0x8.2  // D2 - Clear_status

void set_blink();
void change_time();
void update_1307();
void keyscan();
void set_sec();
void set_min();
void set_hour();
void clear_status();
void read_time();
void update_time();
void display();

//===============================================


void set_blink()
{

   switch (mode)
   {
      case 1:  blink_sec=1;   break;
      case 2: {blink_min=1;blink_sec=0;}   break;
      case 3: {blink_hour=1;blink_min=0;} break;
      case 4:
      {
         blink=0;mode = 0;blink_sec=0;
         blink_min=0;blink_hour=0;
      }
      break;
   }
}

void change_time(){ //Ham chon che do, giong nhu o dong ho CASIO, nhan 1 lan la phut, 2 lan la gio....

   if(mode == 1) {blink_sec=1;set_sec();}
   if(mode == 2) {blink_min=1;set_min();}
   if(mode == 3) {blink_hour=1;set_hour();}
   if(mode == 4)
   {
      blink=0;mode = 0;
      blink_sec=0; blink_min=0; blink_hour=0;
   } 
}


void update_1307() 
{
   write_DS1307(0,sec);
   write_DS1307(1,min);
   bit_set(hour,6);
   if (ampm == 0) {bit_clear(hour,5); write_DS1307(2,hour);} // AM
   if (ampm == 1) {bit_set  (hour,5); write_DS1307(2,hour);} // PM
   
}
void keyscan() {
   RD0=1;RD1=1;RD2=1;RD3=1;
   if(SW1 != 1)   { key=0;SW1=1;delay_ms(150);}
   if(SW2 != 1)   { key=1;SW2=1;delay_ms(150);}
   if(SW3 != 1)   { key=2;SW3=1;delay_ms(150);}
   if(key != 5)
     {
      switch (key)
      {
         case 0: {mode++;key = 5;blink=1;set_blink();}
         break;
         case 1: {change_time();key = 5;update_1307();}
         break;
         case 2: {clear_status();key = 5;}
         break;  
      }
    }
}

void set_sec()
{
       sec=read_ds1307(0);
       if (sec>=0x30) {sec=0; min++; write_ds1307(1,min);}
       else sec=0;
       write_ds1307(0,sec);
}
void set_min()
{ byte j;
 
            min=read_ds1307(1);
            min++;
            j=min & 0x0F;
            if (j>=0x0A) min=min+0x06;
            if (min>=0x60) min=0;
            write_ds1307(1,min);
}
void set_hour()
{  
   hour= hour & 0x1F;
   hour++;
   if(hour== 0x0a) hour = hour+0x06;
   if(hour == 0x13)
   { hour = 0x00;
     if (ampm == 0) ampm = 1;
     else ampm = 0;
   }
}

void clear_status() {

 mode=4;  set_blink();
}
void read_time() 
{
     sec  = read_DS1307(0);
     min  = read_DS1307(1);
     hour = read_DS1307(2);
     update_time();
}

void update_time()
{
  
   ampm = bit_test(hour,5);   //test AM PM
   if(ampm == 0)  {RD4 = 0;RD5=1;}   //AM
   if(ampm == 1)  {RD4 = 1;RD5=0;}   // PM
    DIS1= sec & 0x0F;
    DIS2=(sec & 0xF0)>>4; //convert to BCD SEC
    DIS3= min & 0x0F;
    DIS4=(min & 0xF0)>>4; //convert to BCD MIN
    DIS5= hour & 0x0F;
    DIS6=(hour & 0x10)>>4; //convert to BCD HOUR
   
}
void display() {
TRISB=0x00;TRISA=0x00;
   if(blink==0) goto norm;
   if(on_off==0) goto led_blink;
norm:
// sec - min - hour
      PortB=MAP[DIS1];  RA5=0;//DIS1
      delay_ms(1);         RA5=1;
      PortB=MAP[DIS2];  RA4=0;  //DIS2
      delay_ms(1);         RA4=1;
      PortB=MAP[DIS3];output_low(PIN_B7);RA3=0;//DIS3
      delay_ms(1);         RA3=1;
      PortB=MAP[DIS4];  RA2=0;//DIS4
      delay_ms(1);         RA2=1;
      PortB=MAP[DIS5];output_low(PIN_B7);  RA1=0;//DIS5
      delay_ms(1);         RA1=1;
      PortB=MAP[DIS6];if (portb==0xC0) RA0=1; else RA0=0;//DIS6
      delay_ms(1);         RA0=1;//*/
      
      if(count!=0) goto exit;
      else
      {
         count=15;
         on_off=0;
      }
      goto exit;
      
led_blink:
      PortB=MAP[DIS1];
      if (blink_sec==1) RA5=1;//DIS1
      else RA5=0;
      delay_ms(3);         RA5=1;
      PortB=MAP[DIS2];
      if (blink_sec==1) RA4=1;//DIS2
      else RA4=0;
      delay_ms(3);         RA4=1;
      PortB=MAP[DIS3];output_low(PIN_B7);
      if(blink_min==1)     RA3=1;//DIS3
      else RA3=0;//DIS3
      delay_ms(3);         RA3=1;
      PortB=MAP[DIS4];
      if(blink_min==1)     RA2=1;//DIS4
      else RA2=0;//DIS4
      delay_ms(3);         RA2=1;
      PortB=MAP[DIS5];output_low(PIN_B7);
      if(blink_hour==1)    RA1=1;//DIS5
      else RA1=0;//DIS5
      delay_ms(3);         RA1=1;
      PortB=MAP[DIS6];
      if(blink_hour==1)    RA0=1;//DIS6
      else {if (portb==0xC0) RA0=1; else RA0=0;}//DIS6
      delay_ms(3);         RA0=1;//*/
      if(count==0) {count=15;on_off=1;}
      
exit:
      count--;
}
void main() {
byte u;
 Delay_ms(5);
 Trisd = 0x0F;
 Trisb = 0x00;//output
 Trisa = 0x00;
 RD4=1;RD5=1;
 init_ds1307();
 u=read_ds1307(0);
 sec=u & 0x7F;// enable RTC
 write_ds1307(0,sec);// set second to 00 and enable clock(bit7=0)

//Xoa tat ca cac co dieu khien
 key=5;mode=0;blink=0;
 blink_sec=0;blink_min=0;blink_hour=0;
 count=15;on_off=1;
   ampm = bit_test(hour,5);// test AM_PM
   if(ampm==0)  {RD4 = 0;RD5=1;}   //LED AM 
   if(ampm==1)  {RD4 = 1;RD5=0;}   //LED PM
while(true) 
   {
   read_time();
   display();
   keyscan();
   }
}//end of main program

[kali]

Chào mọi người!
Mình dùng protues mô phỏng con DS1307.
Mình đã nạp vào thanh ghi điều khiển 0x07 của DS1307 giá trị 0x10, tức mình muốn nó phát xung 1Hz ở chân Sout, nhưng trong protues thì nó lại phát xung 0.5Hz.
Bạn nào giải thích hộ mình nguyên nhân được không.
Thanks.