#include <reg51.h>
#include <intrins.h>
#include <stdio.h>
#include <ctype.h>
#define LongToBin(n) \

((n >> 21) & 0x80) | \
((n >> 18) & 0x40) | \
((n >> 15) & 0x20) | \
((n >> 12) & 0x10) | \
((n >> 9) & 0x08) | \
((n >> 6) & 0x04) | \
((n >> 3) & 0x02) | \
((n ) & 0x01) \
)

#define Bin(n) LongToBin(0x##n##l)

// HEX轉BCD
//bcd_data(<0x255,>0)
unsigned char BCD2HEX(unsigned int bcd_data)
{
    unsigned char temp;
    temp=((bcd_data>>8)*100)|((bcd_data>>4)*10)|(bcd_data&0x0f);
    return temp;
}
// HEX轉BCD
//hex_data(<0xff,>0)
unsigned int HEX2BCD(unsigned char hex_data)
{
    unsigned int bcd_data;
    unsigned char temp;
    temp=hex_data%100;
    bcd_data=((unsigned int)hex_data)/100<<8;
    bcd_data=bcd_data|temp/10<<4;
    bcd_data=bcd_data|temp%10;
    return bcd_data;
}

void main(void)
{
  unsigned int c;

  c= Bin(10101001);                               // c = 0xA9
  c=BCD2HEX(0x255);                            //255 轉成HEX為0xff
  c=HEX2BCD(0xff);                            //0xff 轉成BCD碼為 255
}