void CRC16_S(byte[] data, int len)
{
byte CRC16Lo;
byte CRC16Hi; //CRC寄存器
byte CL; byte CH; //多项式码&HA001
byte SaveHi; byte SaveLo;
int Flag;
CRC16Lo = 0xFF;
CRC16Hi = 0xFF;
CL = 0x01;
CH = 0xA0;
for (int i = 0; i < len; i++)
{
CRC16Lo = (byte)(CRC16Lo ^ data[i]); //每一个数据与CRC寄存器进行异或
for (Flag = 0; Flag <= 7; Flag++)
{
SaveHi = CRC16Hi;
SaveLo = CRC16Lo;
CRC16Hi = (byte)(CRC16Hi >> 1); //高位右移一位
CRC16Lo = (byte)(CRC16Lo >> 1); //低位右移一位
if ((SaveHi & 0x01) == 0x01) //如果高位字节位为1
{
CRC16Lo = (byte)(CRC16Lo | 0x80); //则低位字节右移后前面补1
} //否则自动补0
if ((SaveLo & 0x01) == 0x01) //如果LSB为1，则与多项式码进行异或
{
CRC16Hi = (byte)(CRC16Hi ^ CH);
CRC16Lo = (byte)(CRC16Lo ^ CL);
}
}
}
//如果是modbus协议的话，应该是是低位，第二位是高位
data[len++] = CRC16Lo; //CRC低位
data[len] = CRC16Hi; //CRC 高位
}