/*
* 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: mbfuncholding.c,v 1.12 2007/02/18 23:48:22 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 + 0)
#define MB_PDU_FUNC_READ_REGCNT_OFF ( MB_PDU_DATA_OFF + 2 )
#define MB_PDU_FUNC_READ_SIZE ( 4 )
#define MB_PDU_FUNC_READ_REGCNT_MAX ( 0x007D )
#define MB_PDU_FUNC_WRITE_ADDR_OFF ( MB_PDU_DATA_OFF + 0)
#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 + 0 )
#define MB_PDU_FUNC_WRITE_MUL_REGCNT_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_REGCNT_MAX ( 0x0078 )
#define MB_PDU_FUNC_READWRITE_READ_ADDR_OFF ( MB_PDU_DATA_OFF + 0 )
#define MB_PDU_FUNC_READWRITE_READ_REGCNT_OFF ( MB_PDU_DATA_OFF + 2 )
#define MB_PDU_FUNC_READWRITE_WRITE_ADDR_OFF ( MB_PDU_DATA_OFF + 4 )
#define MB_PDU_FUNC_READWRITE_WRITE_REGCNT_OFF ( MB_PDU_DATA_OFF + 6 )
#define MB_PDU_FUNC_READWRITE_BYTECNT_OFF ( MB_PDU_DATA_OFF + 8 )
#define MB_PDU_FUNC_READWRITE_WRITE_VALUES_OFF ( MB_PDU_DATA_OFF + 9 )
#define MB_PDU_FUNC_READWRITE_SIZE_MIN ( 9 )
/* ----------------------- Static functions ---------------------------------*/
eMBException prveMBError2Exception( eMBErrorCode eErrorCode );
/* ----------------------- Start implementation -----------------------------*/
#if MB_FUNC_WRITE_HOLDING_ENABLED > 0
eMBException
eMBFuncWriteHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
{
USHORT usRegAddress;
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] );
//Comment out next line if you do not want to make reg addresses one-based!
usRegAddress++;
/* Make callback to update the value. */
eRegStatus = eMBRegHoldingCB( &pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF],
usRegAddress, 1, MB_REG_WRITE );
/* If an error occured convert it into a Modbus exception. */
if( eRegStatus != MB_ENOERR )
{
eStatus = prveMBError2Exception( eRegStatus );
}
}
else
{
/* Can't be a valid request because the length is incorrect. */
eStatus = MB_EX_ILLEGAL_DATA_VALUE;
}
return eStatus;
}
#endif
#if MB_FUNC_WRITE_MULTIPLE_HOLDING_ENABLED > 0
eMBException
eMBFuncWriteMultipleHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
{
USHORT usRegAddress;
USHORT usRegCount;
UCHAR ucRegByteCount;
eMBException eStatus = MB_EX_NONE;
eMBErrorCode eRegStatus;
if( *usLen >= ( MB_PDU_FUNC_WRITE_MUL_SIZE_MIN + 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] );
//Comment out next line if you do not want to make reg addresses one-based!
usRegAddress++;
usRegCount = ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_REGCNT_OFF] << 8 );
usRegCount |= ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_REGCNT_OFF + 1] );
ucRegByteCount = pucFrame[MB_PDU_FUNC_WRITE_MUL_BYTECNT_OFF];
if( ( usRegCount >= 1 ) &&
( usRegCount <= MB_PDU_FUNC_WRITE_MUL_REGCNT_MAX ) &&
( ucRegByteCount == ( UCHAR ) ( 2 * usRegCount ) ) )
{
/* Make callback to update the register values. */
eRegStatus =
eMBRegHoldingCB( &pucFrame[MB_PDU_FUNC_WRITE_MUL_VALUES_OFF],
usRegAddress, usRegCount, 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 request because the length is incorrect. */
eStatus = MB_EX_ILLEGAL_DATA_VALUE;
}
return eStatus;
}
#endif
#if MB_FUNC_READ_HOLDING_ENABLED > 0
eMBException
eMBFuncReadHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
{
USHORT usRegAddress;
USHORT usRegCount;
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] );
//Comment out next line if you do not want to make reg addresses one-based!
usRegAddress++;
usRegCount = ( USHORT )( pucFrame[MB_PDU_FUNC_READ_REGCNT_OFF] << 8 );
usRegCount = ( USHORT )( pucFrame[MB_PDU_FUNC_READ_REGCNT_OFF + 1] );
/* Check if the number of registers to read is valid. If not
* return Modbus illegal data value exception.
*/
if( ( usRegCount >= 1 ) && ( usRegCount <= MB_PDU_FUNC_READ_REGCNT_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_HOLDING_REGISTER;
*usLen += 1;
/* Second byte in the response contain the number of bytes. */
*pucFrameCur++ = ( UCHAR ) ( usRegCount * 2 );
*usLen += 1;
/* Make callback to fill the buffer. */
eRegStatus = eMBRegHoldingCB( pucFrameCur, usRegAddress, usRegCount, MB_REG_READ );
/* If an error occured convert it into a Modbus exception. */
if( eRegStatus != MB_ENOERR )
{
eStatus = prveMBError2Exception( eRegStatus );
}
else
{
*usLen += usRegCount * 2;
}
}
else
{
eStatus = MB_EX_ILLEGAL_DATA_VALUE;
}
}
else
{
/* Can't be a valid request because the length is incorrect. */
eStatus = MB_EX_ILLEGAL_DATA_VALUE;
}
return eStatus;
}
#endif
#if MB_FUNC_READWRITE_HOLDING_ENABLED > 0
eMBException
eMBFuncReadWriteMultipleHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
{
USHORT usRegReadAddress;
USHORT usRegReadCount;
USHORT usRegWriteAddress;
USHORT usRegWriteCount;
UCHAR ucRegWriteByteCount;
UCHAR *pucFrameCur;
eMBException eStatus = MB_EX_NONE;
eMBErrorCode eRegStatus;
if( *usLen >= ( MB_PDU_FUNC_READWRITE_SIZE_MIN + MB_PDU_SIZE_MIN ) )
{
usRegReadAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_READ_ADDR_OFF] << 8U );
usRegReadAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_READ_ADDR_OFF + 1] );
//Comment out next line if you do not want to make reg addresses one-based!
usRegReadAddress++;
usRegReadCount = ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_READ_REGCNT_OFF] << 8U );
usRegReadCount |= ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_READ_REGCNT_OFF + 1] );
usRegWriteAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_WRITE_ADDR_OFF] << 8U );
usRegWriteAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_WRITE_ADDR_OFF + 1] );
//Comment out next line if you do not want to make reg addresses one-based!
usRegWriteAddress++;
usRegWriteCount = ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_WRITE_REGCNT_OFF] << 8U );
usRegWriteCount |= ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_WRITE_REGCNT_OFF + 1] );
ucRegWriteByteCount = pucFrame[MB_PDU_FUNC_READWRITE_BYTECNT_OFF];
if( ( usRegReadCount >= 1 ) && ( usRegReadCount <= 0x7D ) &&
( usRegWriteCount >= 1 ) && ( usRegWriteCount <= 0x79 ) &&
( ( 2 * usRegWriteCount ) == ucRegWriteByteCount ) )
{
/* Make callback to update the register values. */
eRegStatus = eMBRegHoldingCB( &pucFrame[MB_PDU_FUNC_READWRITE_WRITE_VALUES_OFF],
usRegWriteAddress, usRegWriteCount, MB_REG_WRITE );
if( eRegStatus == MB_ENOERR )
{
/* 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_READWRITE_MULTIPLE_REGISTERS;
*usLen += 1;
/* Second byte in the response contain the number of bytes. */
*pucFrameCur++ = ( UCHAR ) ( usRegReadCount * 2 );
*usLen += 1;
/* Make the read callback. */
eRegStatus =
eMBRegHoldingCB( pucFrameCur, usRegReadAddress, usRegReadCount, MB_REG_READ );
if( eRegStatus == MB_ENOERR )
{
*usLen += 2 * usRegReadCount;
}
}
if( eRegStatus != MB_ENOERR )
{
eStatus = prveMBError2Exception( eRegStatus );
}
}
else
{
eStatus = MB_EX_ILLEGAL_DATA_VALUE;
}
}
return eStatus;
}
#endif
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