mbcrc.c
上传用户:kongshuqi
上传日期:2013-10-09
资源大小:59k
文件大小:5k
- /*
- * FreeModbus Libary: A portable Modbus implementation for Modbus ASCII/RTU.
- * Copyright (C) 2006 Christian Walter <wolti@sil.at>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- *
- * File: $Id: mbcrc.c,v 1.4 2006/05/13 12:34:32 wolti Exp $
- */
- /* ----------------------- Platform includes --------------------------------*/
- #include "port.h"
- static const UCHAR aucCRCHi[] = {
- 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,
- 0x00, 0xC1, 0x81,
- 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81,
- 0x40, 0x01, 0xC0,
- 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1,
- 0x81, 0x40, 0x01,
- 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01,
- 0xC0, 0x80, 0x41,
- 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
- 0x00, 0xC1, 0x81,
- 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80,
- 0x41, 0x01, 0xC0,
- 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,
- 0x80, 0x41, 0x01,
- 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00,
- 0xC1, 0x81, 0x40,
- 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,
- 0x00, 0xC1, 0x81,
- 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81,
- 0x40, 0x01, 0xC0,
- 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1,
- 0x81, 0x40, 0x01,
- 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01,
- 0xC0, 0x80, 0x41,
- 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
- 0x00, 0xC1, 0x81,
- 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81,
- 0x40, 0x01, 0xC0,
- 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,
- 0x80, 0x41, 0x01,
- 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01,
- 0xC0, 0x80, 0x41,
- 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,
- 0x00, 0xC1, 0x81,
- 0x40
- };
- static const UCHAR aucCRCLo[] = {
- 0x00, 0xC0, 0xC1, 0x01, 0xC3, 0x03, 0x02, 0xC2, 0xC6, 0x06, 0x07, 0xC7,
- 0x05, 0xC5, 0xC4,
- 0x04, 0xCC, 0x0C, 0x0D, 0xCD, 0x0F, 0xCF, 0xCE, 0x0E, 0x0A, 0xCA, 0xCB,
- 0x0B, 0xC9, 0x09,
- 0x08, 0xC8, 0xD8, 0x18, 0x19, 0xD9, 0x1B, 0xDB, 0xDA, 0x1A, 0x1E, 0xDE,
- 0xDF, 0x1F, 0xDD,
- 0x1D, 0x1C, 0xDC, 0x14, 0xD4, 0xD5, 0x15, 0xD7, 0x17, 0x16, 0xD6, 0xD2,
- 0x12, 0x13, 0xD3,
- 0x11, 0xD1, 0xD0, 0x10, 0xF0, 0x30, 0x31, 0xF1, 0x33, 0xF3, 0xF2, 0x32,
- 0x36, 0xF6, 0xF7,
- 0x37, 0xF5, 0x35, 0x34, 0xF4, 0x3C, 0xFC, 0xFD, 0x3D, 0xFF, 0x3F, 0x3E,
- 0xFE, 0xFA, 0x3A,
- 0x3B, 0xFB, 0x39, 0xF9, 0xF8, 0x38, 0x28, 0xE8, 0xE9, 0x29, 0xEB, 0x2B,
- 0x2A, 0xEA, 0xEE,
- 0x2E, 0x2F, 0xEF, 0x2D, 0xED, 0xEC, 0x2C, 0xE4, 0x24, 0x25, 0xE5, 0x27,
- 0xE7, 0xE6, 0x26,
- 0x22, 0xE2, 0xE3, 0x23, 0xE1, 0x21, 0x20, 0xE0, 0xA0, 0x60, 0x61, 0xA1,
- 0x63, 0xA3, 0xA2,
- 0x62, 0x66, 0xA6, 0xA7, 0x67, 0xA5, 0x65, 0x64, 0xA4, 0x6C, 0xAC, 0xAD,
- 0x6D, 0xAF, 0x6F,
- 0x6E, 0xAE, 0xAA, 0x6A, 0x6B, 0xAB, 0x69, 0xA9, 0xA8, 0x68, 0x78, 0xB8,
- 0xB9, 0x79, 0xBB,
- 0x7B, 0x7A, 0xBA, 0xBE, 0x7E, 0x7F, 0xBF, 0x7D, 0xBD, 0xBC, 0x7C, 0xB4,
- 0x74, 0x75, 0xB5,
- 0x77, 0xB7, 0xB6, 0x76, 0x72, 0xB2, 0xB3, 0x73, 0xB1, 0x71, 0x70, 0xB0,
- 0x50, 0x90, 0x91,
- 0x51, 0x93, 0x53, 0x52, 0x92, 0x96, 0x56, 0x57, 0x97, 0x55, 0x95, 0x94,
- 0x54, 0x9C, 0x5C,
- 0x5D, 0x9D, 0x5F, 0x9F, 0x9E, 0x5E, 0x5A, 0x9A, 0x9B, 0x5B, 0x99, 0x59,
- 0x58, 0x98, 0x88,
- 0x48, 0x49, 0x89, 0x4B, 0x8B, 0x8A, 0x4A, 0x4E, 0x8E, 0x8F, 0x4F, 0x8D,
- 0x4D, 0x4C, 0x8C,
- 0x44, 0x84, 0x85, 0x45, 0x87, 0x47, 0x46, 0x86, 0x82, 0x42, 0x43, 0x83,
- 0x41, 0x81, 0x80,
- 0x40
- };
- USHORT
- usMBCRC16( UCHAR * pucFrame, USHORT usLen )
- {
- UCHAR ucCRCHi = 0xFF;
- UCHAR ucCRCLo = 0xFF;
- int iIndex;
- while( usLen-- )
- {
- iIndex = ucCRCLo ^ *( pucFrame++ );
- ucCRCLo = ucCRCHi ^ aucCRCHi[iIndex];
- ucCRCHi = aucCRCLo[iIndex];
- }
- return ucCRCHi << 8 | ucCRCLo;
- }