unsigned int add2CRC16(unsigned char  newData,
                       unsigned int   oldCRC,
                       unsigned int   genPoly)
{
    int  i = 8;

    oldCRC ^= newData;

    for(i = 8; i; i--)
    {
        if(oldCRC & 1)
        {
            oldCRC = (oldCRC >>= 1) ^ genPoly;
        }
        else
        {
            oldCRC >>= 1;
        }
    }
    
    return oldCRC;
}