cak.rar_CRC12

typedef unsigned char BYTE; typedef unsigned short WORD; typedef unsigned long DWORD; /*============================================================== 移位法CRC12校验码计算函数 ================================================================*/ WORD CRC12(BYTE acbyBuff[], int iLen) { WORD wCRC; int i, iQ; BYTE iR; wCRC = 0; iQ = 0; iR = 0; while(iQ < iLen) { /*多项式除法*/ /*如果该位为1*/ if(acbyBuff[iQ] & (0x80>>iR)) /*则在余数尾部添1否则添0*/ wCRC |= 0x01; /*如果12位除数中的最高位为1，则够除*/ if(wCRC >= 0x1000) wCRC ^= 0x180D; wCRC <<= 1; iR++; if(iR == 8) { iR = 0; iQ++; } } /*对后面添加的12个0做处理*/ for(i=0; i<12; i++) { if(wCRC >= 0x1000) wCRC ^= 0x180D; wCRC <<= 1; } wCRC >>= 1; return wCRC; } /*============================================================== 查表法CRC12校验码计算函数 ================================================================*/ WORD TableCRC12(BYTE buff[], int len) { int n; WORD Cn; BYTE ab, fg; WORD awCRC_Code[] = { 0x0000, 0x080D, 0x0817, 0x001A, 0x0823, 0x002E, 0x0034, 0x0839, 0x084B, 0x0046, 0x005C, 0x0851, 0x0068, 0x0865, 0x087F, 0x0072, 0x089B, 0x0096, 0x008C, 0x0881, 0x00B8, 0x08B5, 0x08AF, 0x00A2, 0x00D0, 0x08DD, 0x08C7, 0x00CA, 0x08F3, 0x00FE, 0x00E4, 0x08E9, 0x093B, 0x0136, 0x012C, 0x0921, 0x0118, 0x0915, 0x090F, 0x0102, 0x0170, 0x097D, 0x0967, 0x016A, 0x0953, 0x015E, 0x0144, 0x0949, 0x01A0, 0x09AD, 0x09B7, 0x01BA, 0x0983, 0x018E, 0x0194, 0x0999, 0x09EB, 0x01E6, 0x01FC, 0x09F1, 0x01C8, 0x09C5, 0x09DF, 0x01D2, 0x0A7B, 0x0276, 0x026C, 0x0A61, 0x0258, 0x0A55, 0x0A4F, 0x0242, 0x0230, 0x0A3D, 0x0A27, 0x022A, 0x0A13, 0x021E, 0x0204, 0x0A09, 0x02E0, 0x0AED, 0x0AF7, 0x02FA, 0x0AC3, 0x02CE, 0x02D4, 0x0AD9, 0x0AAB, 0x02A6, 0x02BC, 0x0AB1, 0x0288, 0x0A85, 0x0A9F, 0x0292, 0x0340, 0x0B4D, 0x0B57, 0x035A, 0x0B63, 0x036E, 0x0374, 0x0B79, 0x0B0B, 0x0306, 0x031C, 0x0B11, 0x0328, 0x0B25, 0x0B3F, 0x0332, 0x0BDB, 0x03D6, 0x03CC, 0x0BC1, 0x03F8, 0x0BF5, 0x0BEF, 0x03E2, 0x0390, 0x0B9D, 0x0B87, 0x038A, 0x0BB3, 0x03BE, 0x03A4, 0x0BA9, 0x0CFB, 0x04F6, 0x04EC, 0x0CE1, 0x04D8, 0x0CD5, 0x0CCF, 0x04C2, 0x04B0, 0x0CBD, 0x0CA7, 0x04AA, 0x0C93, 0x049E, 0x0484, 0x0C89, 0x0460, 0x0C6D, 0x0C77, 0x047A, 0x0C43, 0x044E, 0x0454, 0x0C59, 0x0C2B, 0x0426, 0x043C, 0x0C31, 0x0408, 0x0C05, 0x0C1F, 0x0412, 0x05C0, 0x0DCD, 0x0DD7, 0x05DA, 0x0DE3, 0x05EE, 0x05F4, 0x0DF9, 0x0D8B, 0x0586, 0x059C, 0x0D91, 0x05A8, 0x0DA5, 0x0DBF, 0x05B2, 0x0D5B, 0x0556, 0x054C, 0x0D41, 0x0578, 0x0D75, 0x0D6F, 0x0562, 0x0510, 0x0D1D, 0x0D07, 0x050A, 0x0D33, 0x053E, 0x0524, 0x0D29, 0x0680, 0x0E8D, 0x0E97, 0x069A, 0x0EA3, 0x06AE, 0x06B4, 0x0EB9, 0x0ECB, 0x06C6, 0x06DC, 0x0ED1, 0x06E8, 0x0EE5, 0x0EFF, 0x06F2, 0x0E1B, 0x0616, 0x060C, 0x0E01, 0x0638, 0x0E35, 0x0E2F, 0x0622, 0x0650, 0x0E5D, 0x0E47, 0x064A, 0x0E73, 0x067E, 0x0664, 0x0E69, 0x0FBB, 0x07B6, 0x07AC, 0x0FA1, 0x0798, 0x0F95, 0x0F8F, 0x0782, 0x07F0, 0x0FFD, 0x0FE7, 0x07EA, 0x0FD3, 0x07DE, 0x07C4, 0x0FC9, 0x0720, 0x0F2D, 0x0F37, 0x073A, 0x0F03, 0x070E, 0x0714, 0x0F19, 0x0F6B, 0x0766, 0x077C, 0x0F71, 0x0748, 0x0F45, 0x0F5F, 0x0752 }; // 第n个字节Bn求CRC12相当于 // Bn 00 00 添12个0对180DH求余 // Bn:xy 00 0 // ----------------- // |(Hi) |(Lo) // Cn: | ab | c // Bn+1 | de | 0 00 // +-----+--------- // B'n | fg | c 00 B'n = Bn+1^Cn_Hi 查表求得Tn的校验码 C'n = i jk // C'n i jk // ---------- // l jk // // Cn+1 = ((Cn&0x0F) << 8) ^ C'n Cn = 0; for(n=0; n<len; n++) { ab = ( Cn & 0x0FF0 ) >> 4; fg = buff[n]^ab; Cn = ((Cn&0x000F) << 8) ^ awCRC_Code[fg]; } return Cn; } main () { WORD crc; unsigned char ab[]={0x55,0x44,0x33,0x22,0x11}; crc=TableCRC12(ab, 5); // crc=CRC12(ab, 5); printf("%x\n",crc); }