/*
* FreeModbus Libary: A portable Modbus implementation for Modbus ASCII/RTU.
* Copyright (c) 2006 Christian Walter <wolti@sil.at>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* File: $Id: mbfunccoils.c,v 1.8 2007/02/18 23:47:16 wolti Exp $
*/
/* ----------------------- System includes ----------------------------------*/
#include "stdlib.h"
#include "string.h"
/* ----------------------- Platform includes --------------------------------*/
#include "port.h"
/* ----------------------- Modbus includes ----------------------------------*/
#include "mb.h"
#include "mbframe.h"
#include "mbproto.h"
#include "mbconfig.h"
/* ----------------------- Defines ------------------------------------------*/
#define MB_PDU_FUNC_READ_ADDR_OFF ( MB_PDU_DATA_OFF )
#define MB_PDU_FUNC_READ_COILCNT_OFF ( MB_PDU_DATA_OFF + 2 )
#define MB_PDU_FUNC_READ_SIZE ( 4 )
#define MB_PDU_FUNC_READ_COILCNT_MAX ( 0x07D0 )
#define MB_PDU_FUNC_WRITE_ADDR_OFF ( MB_PDU_DATA_OFF )
#define MB_PDU_FUNC_WRITE_VALUE_OFF ( MB_PDU_DATA_OFF + 2 )
#define MB_PDU_FUNC_WRITE_SIZE ( 4 )
#define MB_PDU_FUNC_WRITE_MUL_ADDR_OFF ( MB_PDU_DATA_OFF )
#define MB_PDU_FUNC_WRITE_MUL_COILCNT_OFF ( MB_PDU_DATA_OFF + 2 )
#define MB_PDU_FUNC_WRITE_MUL_BYTECNT_OFF ( MB_PDU_DATA_OFF + 4 )
#define MB_PDU_FUNC_WRITE_MUL_VALUES_OFF ( MB_PDU_DATA_OFF + 5 )
#define MB_PDU_FUNC_WRITE_MUL_SIZE_MIN ( 5 )
#define MB_PDU_FUNC_WRITE_MUL_COILCNT_MAX ( 0x07B0 )
/* ----------------------- Static functions ---------------------------------*/
eMBException prveMBError2Exception( eMBErrorCode eErrorCode );
/* ----------------------- Start implementation -----------------------------*/
#if MB_FUNC_READ_COILS_ENABLED > 0
eMBException
eMBFuncReadCoils( UCHAR * pucFrame, USHORT * usLen )
{
USHORT usRegAddress;
USHORT usCoilCount;
UCHAR ucNBytes;
UCHAR *pucFrameCur;
eMBException eStatus = MB_EX_NONE;
eMBErrorCode eRegStatus;
if( *usLen == ( MB_PDU_FUNC_READ_SIZE + MB_PDU_SIZE_MIN ) )
{
usRegAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_READ_ADDR_OFF] << 8 );
usRegAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_READ_ADDR_OFF + 1] );
usRegAddress++;
usCoilCount = ( USHORT )( pucFrame[MB_PDU_FUNC_READ_COILCNT_OFF] << 8 );
usCoilCount |= ( USHORT )( pucFrame[MB_PDU_FUNC_READ_COILCNT_OFF + 1] );
/* Check if the number of registers to read is valid. If not
* return Modbus illegal data value exception.
*/
if( ( usCoilCount >= 1 ) &&
( usCoilCount < MB_PDU_FUNC_READ_COILCNT_MAX ) )
{
/* Set the current PDU data pointer to the beginning. */
pucFrameCur = &pucFrame[MB_PDU_FUNC_OFF];
*usLen = MB_PDU_FUNC_OFF;
/* First byte contains the function code. */
*pucFrameCur++ = MB_FUNC_READ_COILS;
*usLen += 1;
/* Test if the quantity of coils is a multiple of 8. If not last
* byte is only partially field with unused coils set to zero. */
if( ( usCoilCount & 0x0007 ) != 0 )
{
ucNBytes = ( UCHAR )( usCoilCount / 8 + 1 );
}
else
{
ucNBytes = ( UCHAR )( usCoilCount / 8 );
}
*pucFrameCur++ = ucNBytes;
*usLen += 1;
eRegStatus =
eMBRegCoilsCB( pucFrameCur, usRegAddress, usCoilCount,
MB_REG_READ );
/* If an error occured convert it into a Modbus exception. */
if( eRegStatus != MB_ENOERR )
{
eStatus = prveMBError2Exception( eRegStatus );
}
else
{
/* The response contains the function code, the starting address
* and the quantity of registers. We reuse the old values in the
* buffer because they are still valid. */
*usLen += ucNBytes;;
}
}
else
{
eStatus = MB_EX_ILLEGAL_DATA_VALUE;
}
}
else
{
/* Can't be a valid read coil register request because the length
* is incorrect. */
eStatus = MB_EX_ILLEGAL_DATA_VALUE;
}
return eStatus;
}
#if MB_FUNC_WRITE_COIL_ENABLED > 0
eMBException
eMBFuncWriteCoil( UCHAR * pucFrame, USHORT * usLen )
{
USHORT usRegAddress;
UCHAR ucBuf[2];
eMBException eStatus = MB_EX_NONE;
eMBErrorCode eRegStatus;
if( *usLen == ( MB_PDU_FUNC_WRITE_SIZE + MB_PDU_SIZE_MIN ) )
{
usRegAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_ADDR_OFF] << 8 );
usRegAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_ADDR_OFF + 1] );
usRegAddress++;
if( ( pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF + 1] == 0x00 ) &&
( ( pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF] == 0xFF ) ||
( pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF] == 0x00 ) ) )
{
ucBuf[1] = 0;
if( pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF] == 0xFF )
{
ucBuf[0] = 1;
}
else
{
ucBuf[0] = 0;
}
eRegStatus =
eMBRegCoilsCB( &ucBuf[0], usRegAddress, 1, MB_REG_WRITE );
/* If an error occured convert it into a Modbus exception. */
if( eRegStatus != MB_ENOERR )
{
eStatus = prveMBError2Exception( eRegStatus );
}
}
else
{
eStatus = MB_EX_ILLEGAL_DATA_VALUE;
}
}
else
{
/* Can't be a valid write coil register request because the length
* is incorrect. */
eStatus = MB_EX_ILLEGAL_DATA_VALUE;
}
return eStatus;
}
#endif
#if MB_FUNC_WRITE_MULTIPLE_COILS_ENABLED > 0
eMBException
eMBFuncWriteMultipleCoils( UCHAR * pucFrame, USHORT * usLen )
{
USHORT usRegAddress;
USHORT usCoilCnt;
UCHAR ucByteCount;
UCHAR ucByteCountVerify;
eMBException eStatus = MB_EX_NONE;
eMBErrorCode eRegStatus;
if( *usLen > ( MB_PDU_FUNC_WRITE_SIZE + MB_PDU_SIZE_MIN ) )
{
usRegAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_ADDR_OFF] << 8 );
usRegAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_ADDR_OFF + 1] );
usRegAddress++;
usCoilCnt = ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_COILCNT_OFF] << 8 );
usCoilCnt |= ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_COILCNT_OFF + 1] );
ucByteCount = pucFrame[MB_PDU_FUNC_WRITE_MUL_BYTECNT_OFF];
/* Compute the number of expected bytes in the request. */
if( ( usCoilCnt & 0x0007 ) != 0 )
{
ucByteCountVerify = ( UCHAR )( usCoilCnt / 8 + 1 );
}
else
{
ucByteCountVerify = ( UCHAR )( usCoilCnt / 8 );
}
if( ( usCoilCnt >= 1 ) &&
( usCoilCnt <= MB_PDU_FUNC_WRITE_MUL_COILCNT_MAX ) &&
( ucByteCountVerify == ucByteCount ) )
{
eRegStatus =
eMBRegCoilsCB( &pucFrame[MB_PDU_FUNC_WRITE_MUL_VALUES_OFF],
usRegAddress, usCoilCnt, MB_REG_WRITE );
/* If an error occured convert it into a Modbus exception. */
if( eRegStatus != MB_ENOERR )
{
eStatus = prveMBError2Exception( eRegStatus );
}
else
{
/* The response contains the function code, the starting address
* and the quantity of registers. We reuse the old values in the
* buffer because they are still valid. */
*usLen = MB_PDU_FUNC_WRITE_MUL_BYTECNT_OFF;
}
}
else
{
eStatus = MB_EX_ILLEGAL_DATA_VALUE;
}
}
else
{
/* Can't be a valid write coil register request because the length
* is incorrect. */
eStatus = MB_EX_ILLEGAL_DATA_VALUE;
}
return eStatus;
}
#endif
#endif
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