#include"..\lib\8000.h"
void WriteRTC(int addr, int data);
int MaxDay[12]={31,28,31,30,31,30,31,31,30,31,30,31};
int IsLeapYear(int year)
{
  if(year%4) return 0;
  if(year%100) return 1;
  if(year%400) return 0;
  return 1;
}


int SetDate(int year,int month,int day)
{ unsigned days,i;

  if(month>12 || month<1) return DateError;
  if(day>31 || day<1) return DateError;
  if(year>2080 || year<2000) return DateError;

  days=365*(year-2000)+5;
  for(i=1;i<month;i++){
    days+=MaxDay[i-1];
  }
  days+=day;
  if(year>2000) days+=(year-1997)/4;
  if(month>2){
     if(IsLeapYear(year)){
	days++;
     }
  }
  Print("Days=%u\n\r",days);
  days=(days%7)+1;

  year%=100;
  _asm mov ax,year
  _asm aam
  _asm shl ah,4
  _asm or  al,ah
  _asm xor ah,ah
  _asm mov year,ax
  WriteRTC(6,year);

  _asm mov ax,month
  _asm aam
  _asm shl ah,4
  _asm or  al,ah
  _asm xor ah,ah
  _asm mov month,ax
  WriteRTC(4,month);
  _asm mov ax,day
  _asm aam
  _asm shl ah,4
  _asm or  al,ah
  _asm xor ah,ah
  _asm mov day,ax
  WriteRTC(3,day);
  WriteRTC(5,days);
  return NoError;
}

void SetWeekDay(int day)
{
  if(day>=1 &&  day<=7) WriteRTC(5,day);
}