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十进制转BCD
unsigned char NumToBCD(unsigned char num)
{
unsigned char a, b, bcd;
a = (num % 10) & 0x0f;
b = ((num / 10) << 4) & 0xf0;
bcd = a | b;
return bcd;
}BCD转十进制
unsigned char BCDToNum(unsigned char bcd)
{
unsigned char a, b;
a = (bcd >> 4);
b = bcd & 0x0f;
return (a * 10 + b);
}