16bit CRC算法C语言实现

#define CRC_16_POLYNOMIALS            0x8005

unsigned short CRC16_3(unsigned char* pchMsg, unsigned short wDataLen) // 1. MSB first; 2. Initial value is 0000;
{
    unsigned char i, chChar;
    unsigned short wCRC = ;
    while (wDataLen--)
    {
        chChar = *pchMsg++;
        wCRC ^= (((unsigned short) chChar) << );
        for (i = ; i < ; i++)
        {
            if (wCRC & 0x8000)
                wCRC = (wCRC << ) ^ CRC_16_POLYNOMIALS;
            else
                wCRC <<= ;
        }
    }

    return wCRC;
}

备注：多项式0x8005的含义是： x^15 + x^2 + 1