CRC16计算算法教学资料

1、CRC 1 6 计 算 算 法CRC 16计算算法XOR =异或N =字节的信息位POLY = CRC 16 多项式计算=1010 0000 0000 0001（生成多项式=1 + X2 + x 15 + x 16）在CRC 16中，发送的第一个字节为低字节.CRC计算示例（帧02 07）CRC寄存器初始化1111111111111111XOR第一个字符00000000000000001111111111111101移位1011111111111111011010000000000001标志1, XOR多项式1101111111111111移位20110111111111111 1标志1, X

2、OR多项式10100000000000011100111111111110移位301100111111111100移位40011001111111111110100000000000011001001111111110移位501001001111111110移位60010010011111111110100000000000011000010011111110移位701000010011111110移位800100001001111110101000000000000110000001001111100000000000000111XOR第二个字符1000000100111001移位10100

3、000010011100110100000000000011110000010011101移位20111000001001110110100000000000011101000001001111移位30110100000100111110100000000000011100100000100110移位401100100000100110移位50011001000001001110100000000000011001001000001000移位601001001000001000移位700100100100000100移位800010010010000010最高有效最低有效帧的CRC 16则为：

4、4112例执行CRC生成的C语言的函数在下面示出。所有的可能的 CRC值都被预装在两个数组中，当计算 报文内容时可以简单的索引即可。一个数组含有16位CRC域的所有256个可能的高位字节，另一个数组含有地位字节的值。这种索引访问CRC的方式提供了比对报文缓冲区的每个新字符都计算新的CRC更快的方法。注意：此函数内部执行高/低CRC字节的交换。此函数返回的是已经经过交换的CRC值。也就是说，从该函数返回的 CRC值可以直接放置于报文用于发送。函数使用两个参数：unsigned char *puchMsg;指向含有用于生成 CRC的二进制数据报文缓冲区的指针unsigned short usDat

5、aLen;报文缓冲区的字节数.usDataLen ) /* 函数以 unsigned short 类型返回CRC生成函数 unsigned short CRC16 ( puchMsgCRC */unsigned char *puchMsg ;*/unsigned short usDataLen ;unsigned char uchCRCHi = 0 xFF ;*/unsigned char uchCRCLo = 0 xFF ;*/unsigned ulndex ;while (usDataLen-)/*用于计算CRC的报文/*报文中的字节数*/* CRC的高字节初始化/* CRC的低字节初始化

6、/* CRC查询表索引*/*完成整个报文缓冲区*/ulndex = uchCRCLo A *puchMsgg+ ;uchCRCLo = uchCRCHi 人 auchCRCHiuIndex; uchCRCHi = auchCRCLouIndex;return (uchCRCHi 8 | uchCRCLo);高字节表/*高位字节的CRC值*/ static unsigned char auchCRCHi口 = 0 x00, 0 xC1,0 x81, 0 x40, 0 x01,0 xC0, 0 x80, 0 x41, 0 x01, 0 xC0, 0 x80, 0 x41, 0 x00, 0 xC1

7、,0 x81,0 x40, 0 x01,0 xC0, 0 x80, 0 x41,0 x00, 0 xC1,0 x81, 0 x40,0 x00, 0 xC1,0 x81, 0 x40, 0 x01,0 xC0,0 x80, 0 x41,0 x01,0 xC0, 0 x80, 0 x41, 0 x00, 0 xC1, 0 x81,0 x40, 0 x00, 0 xC1, 0 x81,0 x40, 0 x01,0 xC0, 0 x80, 0 x41, 0 x00, 0 xC1,0 x81,0 x40, 0 x01, 0 xC0, 0 x80, 0 x41,0 x01,0 xC0, 0 x80, 0

8、 x41,0 x00, 0 xC1,0 x81, 0 x40, 0 x01,0 xC0, 0 x80, 0 x41, 0 x00, 0 xC1,0 x81,0 x40, 0 x00, 0 xC1,0 x81,0 x40, 0 x01,0 xC0, 0 x80, 0 x41,0 x00, 0 xC1,0 x81, 0 x40,0 x01, 0 xC0, 0 x80, 0 x41,0 x01,0 xC0,0 x80, 0 x41,0 x00, 0 xC1,0 x81,0 x40, 0 x00, 0 xC1, 0 x81,0 x40, 0 x01,0 xC0, 0 x80, 0 x41,0 x01,

9、0 xC0, 0 x80, 0 x41, 0 x00, 0 xC1,0 x81,0 x40, 0 x01, 0 xC0, 0 x80, 0 x41,0 x00, 0 xC1,0 x81,0 x40,0 x00, 0 xC1,0 x81, 0 x40, 0 x01,0 xC0, 0 x80, 0 x41, 0 x01, 0 xC0, 0 x80, 0 x41, 0 x00, 0 xC1,0 x81,0 x40, 0 x00, 0 xC1, 0 x81,0 x40, 0 x01, 0 xC0, 0 x80, 0 x41,0 x00, 0 xC1,0 x81, 0 x40, 0 x01,0 xC0,

10、0 x80, 0 x41,0 x01,0 xC0, 0 x80, 0 x41, 0 x00, 0 xC1, 0 x81,0 x40, 0 x00, 0 xC1, 0 x81,0 x40, 0 x01,0 xC0, 0 x80, 0 x41, 0 x01,0 xC0, 0 x80, 0 x41,0 x00, 0 xC1, 0 x81, 0 x40, 0 x01,0 xC0, 0 x80, 0 x41,0 x00, 0 xC1,0 x81, 0 x40, 0 x00, 0 xC1,0 x81,0 x40, 0 x01, 0 xC0, 0 x80, 0 x41, 0 x00, 0 xC1,0 x81

11、,0 x40, 0 x01,0 xC0, 0 x80, 0 x41,0 x01, 0 xC0, 0 x80, 0 x41,0 x00, 0 xC1,0 x81, 0 x40, 0 x01,0 xC0,0 x80, 0 x41,0 x00, 0 xC1,0 x81,0 x40, 0 x00, 0 xC1, 0 x81,0 x40, 0 x01,0 xC0, 0 x80, 0 x41,0 x01,0 xC0, 0 x80, 0 x41, 0 x00, 0 xC1,0 x81,0 x40, 0 x00, 0 xC1, 0 x81, 0 x40, 0 x01,0 xC0, 0 x80, 0 x41,0

12、 x00, 0 xC1,0 x81, 0 x40, 0 x01,0 xC0, 0 x80, 0 x41, 0 x01, 0 xC0, 0 x80, 0 x41, 0 x00, 0 xC1,0 x81,0 x40;低字节表/*低位字节的CRC值*/static char auchCRCLo口 = 0 x00, 0 xC0, 0 xC1,0 x01, 0 xC3, 0 x03, 0 x02, 0 xC2, 0 xC6,0 x06, 0 x07, 0 xC7, 0 x05, 0 xC5, 0 xC4,0 x04, 0 xCC, 0 x0C, 0 x0D, 0 xCD, 0 x0F, 0 xCF, 0

13、 xCE, 0 x0E,0 x0A, 0 xCA, 0 xCB, 0 x0B, 0 xC9, 0 x09,0 x08, 0 xC8, 0 xD8, 0 x18, 0 x19, 0 xD9, 0 x1B, 0 xDB, 0 xDA,0 x1A, 0 x1E, 0 xDE, 0 xDF, 0 x1F, 0 xDD,0 x1D, 0 x1C, 0 xDC, 0 x14, 0 xD4, 0 xD5, 0 x15, 0 xD7, 0 x17,0 x16, 0 xD6, 0 xD2, 0 x12, 0 x13, 0 xD3,0 x11, 0 xD1,0 xD0, 0 x10, 0 xF0, 0 x30,

14、0 x31, 0 xF1,0 x33,0 xF3, 0 xF2, 0 x32, 0 x36, 0 xF6, 0 xF7,0 x37, 0 xF5, 0 x35, 0 x34, 0 xF4, 0 x3C, 0 xFC, 0 xFD, 0 x3D,0 xFF, 0 x3F, 0 x3E, 0 xFE, 0 xFA, 0 x3A,0 x3B, 0 xFB, 0 x39, 0 xF9, 0 xF8, 0 x38, 0 x28, 0 xE8, 0 xE9,0 x29, 0 xEB, 0 x2B, 0 x2A, 0 xEA, 0 xEE,0 x2E, 0 x2F, 0 xEF, 0 x2D, 0 xED,

15、 0 xEC, 0 x2C, 0 xE4, 0 x24,0 x25, 0 xE5, 0 x27, 0 xE7, 0 xE6, 0 x26,0 x22, 0 xE2, 0 xE3, 0 x23, 0 xE1,0 x21,0 x20, 0 xE0, 0 xA0,0 x60, 0 x61,0 xA1, 0 x63, 0 xA3, 0 xA2,0 x62, 0 x66, 0 xA6, 0 xA7, 0 x67, 0 xA5, 0 x65, 0 x64, 0 xA4,0 x6C, 0 xAC, 0 xAD, 0 x6D, 0 xAF, 0 x6F,0 x6E, 0 xAE, 0 xAA, 0 x6A,

16、0 x6B, 0 xAB, 0 x69, 0 xA9, 0 xA8,0 x68, 0 x78, 0 xB8, 0 xB9, 0 x79, 0 xBB,0 x7B, 0 x7A, 0 xBA, 0 xBE, 0 x7E, 0 x7F, 0 xBF, 0 x7D, 0 xBD,0 xBC, 0 x7C, 0 xB4, 0 x74, 0 x75, 0 xB5,0 x77, 0 xB7, 0 xB6, 0 x76, 0 x72, 0 xB2, 0 xB3, 0 x73, 0 xB1,0 x71, 0 x70, 0 xB0, 0 x50, 0 x90, 0 x91,0 x51, 0 x93, 0 x53, 0 x52, 0 x92, 0 x96, 0 x56, 0 x57, 0 x97,0 x55, 0 x95, 0 x94, 0 x54, 0 x9C, 0 x5C,0 x5D, 0 x9D, 0 x5F, 0 x9F, 0 x9E, 0 x5E, 0 x5A, 0 x9A,