root / toolbox / freemodbus / modbus / functions / mbutils.c @ ae250f1a
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/*
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* FreeModbus Libary: A portable Modbus implementation for Modbus ASCII/RTU.
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* Copyright (c) 2006 Christian Walter <wolti@sil.at>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. The name of the author may not be used to endorse or promote products
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* derived from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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* File: $Id: mbutils.c,v 1.6 2007/02/18 23:49:07 wolti Exp $
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*/
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/* ----------------------- System includes ----------------------------------*/
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#include "stdlib.h" |
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#include "string.h" |
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/* ----------------------- Platform includes --------------------------------*/
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#include "port.h" |
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/* ----------------------- Modbus includes ----------------------------------*/
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#include "mb.h" |
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#include "mbproto.h" |
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/* ----------------------- Defines ------------------------------------------*/
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#define BITS_UCHAR 8U |
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/* ----------------------- Start implementation -----------------------------*/
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void
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xMBUtilSetBits( UCHAR * ucByteBuf, USHORT usBitOffset, UCHAR ucNBits, |
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UCHAR ucValue ) |
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{ |
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USHORT usWordBuf; |
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USHORT usMask; |
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USHORT usByteOffset; |
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USHORT usNPreBits; |
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USHORT usValue = ucValue; |
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assert( ucNBits <= 8 );
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assert( ( size_t )BITS_UCHAR == sizeof( UCHAR ) * 8 ); |
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/* Calculate byte offset for first byte containing the bit values starting
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* at usBitOffset. */
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usByteOffset = ( USHORT )( ( usBitOffset ) / BITS_UCHAR ); |
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/* How many bits precede our bits to set. */
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usNPreBits = ( USHORT )( usBitOffset - usByteOffset * BITS_UCHAR ); |
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/* Move bit field into position over bits to set */
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usValue <<= usNPreBits; |
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/* Prepare a mask for setting the new bits. */
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usMask = ( USHORT )( ( 1 << ( USHORT ) ucNBits ) - 1 ); |
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usMask <<= usBitOffset - usByteOffset * BITS_UCHAR; |
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/* copy bits into temporary storage. */
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usWordBuf = ucByteBuf[usByteOffset]; |
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usWordBuf |= ucByteBuf[usByteOffset + 1] << BITS_UCHAR;
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/* Zero out bit field bits and then or value bits into them. */
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usWordBuf = ( USHORT )( ( usWordBuf & ( ~usMask ) ) | usValue ); |
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/* move bits back into storage */
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ucByteBuf[usByteOffset] = ( UCHAR )( usWordBuf & 0xFF );
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ucByteBuf[usByteOffset + 1] = ( UCHAR )( usWordBuf >> BITS_UCHAR );
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} |
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UCHAR |
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xMBUtilGetBits( UCHAR * ucByteBuf, USHORT usBitOffset, UCHAR ucNBits ) |
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{ |
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USHORT usWordBuf; |
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USHORT usMask; |
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USHORT usByteOffset; |
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USHORT usNPreBits; |
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/* Calculate byte offset for first byte containing the bit values starting
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* at usBitOffset. */
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usByteOffset = ( USHORT )( ( usBitOffset ) / BITS_UCHAR ); |
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/* How many bits precede our bits to set. */
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usNPreBits = ( USHORT )( usBitOffset - usByteOffset * BITS_UCHAR ); |
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/* Prepare a mask for setting the new bits. */
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usMask = ( USHORT )( ( 1 << ( USHORT ) ucNBits ) - 1 ); |
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/* copy bits into temporary storage. */
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usWordBuf = ucByteBuf[usByteOffset]; |
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usWordBuf |= ucByteBuf[usByteOffset + 1] << BITS_UCHAR;
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/* throw away unneeded bits. */
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usWordBuf >>= usNPreBits; |
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/* mask away bits above the requested bitfield. */
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usWordBuf &= usMask; |
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return ( UCHAR ) usWordBuf;
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} |
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eMBException |
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prveMBError2Exception( eMBErrorCode eErrorCode ) |
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{ |
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eMBException eStatus; |
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switch ( eErrorCode )
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{ |
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case MB_ENOERR:
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eStatus = MB_EX_NONE; |
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break;
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case MB_ENOREG:
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eStatus = MB_EX_ILLEGAL_DATA_ADDRESS; |
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break;
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case MB_ETIMEDOUT:
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eStatus = MB_EX_SLAVE_BUSY; |
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break;
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default:
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eStatus = MB_EX_SLAVE_DEVICE_FAILURE; |
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break;
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} |
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return eStatus;
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} |