nuttx-apps/modbus/mb.c
2014-04-13 16:24:28 -06:00

418 lines
12 KiB
C

/*
* 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: mb.c,v 1.28 2010/06/06 13:54:40 wolti Exp $
*/
/* ----------------------- System includes ----------------------------------*/
#include <nuttx/config.h>
#include <stdlib.h>
#include <string.h>
/* ----------------------- Platform includes --------------------------------*/
#include "port.h"
/* ----------------------- Modbus includes ----------------------------------*/
#include <apps/modbus/mb.h>
#include <apps/modbus/mbframe.h>
#include <apps/modbus/mbproto.h>
#include <apps/modbus/mbfunc.h>
#include <apps/modbus/mbport.h>
#ifdef CONFIG_MB_RTU_ENABLED
#include "mbrtu.h"
#endif
#ifdef CONFIG_MB_ASCII_ENABLED
#include "mbascii.h"
#endif
#ifdef CONFIG_MB_TCP_ENABLED
#include "mbtcp.h"
#endif
#ifndef MB_PORT_HAS_CLOSE
#define MB_PORT_HAS_CLOSE 0
#endif
/* ----------------------- Static variables ---------------------------------*/
static uint8_t ucMBAddress;
static eMBMode eMBCurrentMode;
static enum
{
STATE_ENABLED,
STATE_DISABLED,
STATE_NOT_INITIALIZED
} eMBState = STATE_NOT_INITIALIZED;
/* Functions pointer which are initialized in eMBInit( ). Depending on the
* mode (RTU or ASCII) the are set to the correct implementations.
*/
static peMBFrameSend peMBFrameSendCur;
static pvMBFrameStart pvMBFrameStartCur;
static pvMBFrameStop pvMBFrameStopCur;
static peMBFrameReceive peMBFrameReceiveCur;
static pvMBFrameClose pvMBFrameCloseCur;
/* Callback functions required by the porting layer. They are called when
* an external event has happend which includes a timeout or the reception
* or transmission of a character.
*/
bool( *pxMBFrameCBByteReceived ) ( void );
bool( *pxMBFrameCBTransmitterEmpty ) ( void );
bool( *pxMBPortCBTimerExpired ) ( void );
bool( *pxMBFrameCBReceiveFSMCur ) ( void );
bool( *pxMBFrameCBTransmitFSMCur ) ( void );
/* An array of Modbus functions handlers which associates Modbus function
* codes with implementing functions.
*/
static xMBFunctionHandler xFuncHandlers[CONFIG_MB_FUNC_HANDLERS_MAX] = {
#ifdef CONFIG_MB_FUNC_OTHER_REP_SLAVEID_ENABLED
{MB_FUNC_OTHER_REPORT_SLAVEID, eMBFuncReportSlaveID},
#endif
#ifdef CONFIG_MB_FUNC_READ_INPUT_ENABLED
{MB_FUNC_READ_INPUT_REGISTER, eMBFuncReadInputRegister},
#endif
#ifdef CONFIG_MB_FUNC_READ_HOLDING_ENABLED
{MB_FUNC_READ_HOLDING_REGISTER, eMBFuncReadHoldingRegister},
#endif
#ifdef CONFIG_MB_FUNC_WRITE_MULTIPLE_HOLDING_ENABLED
{MB_FUNC_WRITE_MULTIPLE_REGISTERS, eMBFuncWriteMultipleHoldingRegister},
#endif
#ifdef CONFIG_MB_FUNC_WRITE_HOLDING_ENABLED
{MB_FUNC_WRITE_REGISTER, eMBFuncWriteHoldingRegister},
#endif
#ifdef CONFIG_MB_FUNC_READWRITE_HOLDING_ENABLED
{MB_FUNC_READWRITE_MULTIPLE_REGISTERS, eMBFuncReadWriteMultipleHoldingRegister},
#endif
#ifdef CONFIG_MB_FUNC_READ_COILS_ENABLED
{MB_FUNC_READ_COILS, eMBFuncReadCoils},
#endif
#ifdef CONFIG_MB_FUNC_WRITE_COIL_ENABLED
{MB_FUNC_WRITE_SINGLE_COIL, eMBFuncWriteCoil},
#endif
#ifdef CONFIG_MB_FUNC_WRITE_MULTIPLE_COILS_ENABLED
{MB_FUNC_WRITE_MULTIPLE_COILS, eMBFuncWriteMultipleCoils},
#endif
#ifdef CONFIG_MB_FUNC_READ_DISCRETE_INPUTS_ENABLED
{MB_FUNC_READ_DISCRETE_INPUTS, eMBFuncReadDiscreteInputs},
#endif
};
/* ----------------------- Start implementation -----------------------------*/
eMBErrorCode
eMBInit( eMBMode eMode, uint8_t ucSlaveAddress, uint8_t ucPort, speed_t ulBaudRate, eMBParity eParity )
{
eMBErrorCode eStatus = MB_ENOERR;
/* check preconditions */
if( ( ucSlaveAddress == MB_ADDRESS_BROADCAST ) ||
( ucSlaveAddress < MB_ADDRESS_MIN ) || ( ucSlaveAddress > MB_ADDRESS_MAX ) )
{
eStatus = MB_EINVAL;
}
else
{
ucMBAddress = ucSlaveAddress;
switch ( eMode )
{
#ifdef CONFIG_MB_RTU_ENABLED
case MB_RTU:
pvMBFrameStartCur = eMBRTUStart;
pvMBFrameStopCur = eMBRTUStop;
peMBFrameSendCur = eMBRTUSend;
peMBFrameReceiveCur = eMBRTUReceive;
pvMBFrameCloseCur = MB_PORT_HAS_CLOSE ? vMBPortClose : NULL;
pxMBFrameCBByteReceived = xMBRTUReceiveFSM;
pxMBFrameCBTransmitterEmpty = xMBRTUTransmitFSM;
pxMBPortCBTimerExpired = xMBRTUTimerT35Expired;
eStatus = eMBRTUInit( ucMBAddress, ucPort, ulBaudRate, eParity );
break;
#endif
#ifdef CONFIG_MB_ASCII_ENABLED
case MB_ASCII:
pvMBFrameStartCur = eMBASCIIStart;
pvMBFrameStopCur = eMBASCIIStop;
peMBFrameSendCur = eMBASCIISend;
peMBFrameReceiveCur = eMBASCIIReceive;
pvMBFrameCloseCur = MB_PORT_HAS_CLOSE ? vMBPortClose : NULL;
pxMBFrameCBByteReceived = xMBASCIIReceiveFSM;
pxMBFrameCBTransmitterEmpty = xMBASCIITransmitFSM;
pxMBPortCBTimerExpired = xMBASCIITimerT1SExpired;
eStatus = eMBASCIIInit( ucMBAddress, ucPort, ulBaudRate, eParity );
break;
#endif
default:
eStatus = MB_EINVAL;
}
if( eStatus == MB_ENOERR )
{
if( !xMBPortEventInit( ) )
{
/* port dependent event module initalization failed. */
eStatus = MB_EPORTERR;
}
else
{
eMBCurrentMode = eMode;
eMBState = STATE_DISABLED;
}
}
}
return eStatus;
}
#ifdef CONFIG_MB_TCP_ENABLED
eMBErrorCode
eMBTCPInit( uint16_t ucTCPPort )
{
eMBErrorCode eStatus = MB_ENOERR;
if( ( eStatus = eMBTCPDoInit( ucTCPPort ) ) != MB_ENOERR )
{
eMBState = STATE_DISABLED;
}
else if( !xMBPortEventInit( ) )
{
/* Port dependent event module initalization failed. */
eStatus = MB_EPORTERR;
}
else
{
pvMBFrameStartCur = eMBTCPStart;
pvMBFrameStopCur = eMBTCPStop;
peMBFrameReceiveCur = eMBTCPReceive;
peMBFrameSendCur = eMBTCPSend;
pvMBFrameCloseCur = MB_PORT_HAS_CLOSE ? vMBTCPPortClose : NULL;
ucMBAddress = MB_TCP_PSEUDO_ADDRESS;
eMBCurrentMode = MB_TCP;
eMBState = STATE_DISABLED;
}
return eStatus;
}
#endif
eMBErrorCode
eMBRegisterCB( uint8_t ucFunctionCode, pxMBFunctionHandler pxHandler )
{
int i;
eMBErrorCode eStatus;
if( ( 0 < ucFunctionCode ) && ( ucFunctionCode <= 127 ) )
{
ENTER_CRITICAL_SECTION( );
if( pxHandler != NULL )
{
for( i = 0; i < CONFIG_MB_FUNC_HANDLERS_MAX; i++ )
{
if( ( xFuncHandlers[i].pxHandler == NULL ) ||
( xFuncHandlers[i].pxHandler == pxHandler ) )
{
xFuncHandlers[i].ucFunctionCode = ucFunctionCode;
xFuncHandlers[i].pxHandler = pxHandler;
break;
}
}
eStatus = ( i != CONFIG_MB_FUNC_HANDLERS_MAX ) ? MB_ENOERR : MB_ENORES;
}
else
{
for( i = 0; i < CONFIG_MB_FUNC_HANDLERS_MAX; i++ )
{
if( xFuncHandlers[i].ucFunctionCode == ucFunctionCode )
{
xFuncHandlers[i].ucFunctionCode = 0;
xFuncHandlers[i].pxHandler = NULL;
break;
}
}
/* Remove can't fail. */
eStatus = MB_ENOERR;
}
EXIT_CRITICAL_SECTION( );
}
else
{
eStatus = MB_EINVAL;
}
return eStatus;
}
eMBErrorCode
eMBClose( void )
{
eMBErrorCode eStatus = MB_ENOERR;
if( eMBState == STATE_DISABLED )
{
if( pvMBFrameCloseCur != NULL )
{
pvMBFrameCloseCur( );
}
}
else
{
eStatus = MB_EILLSTATE;
}
return eStatus;
}
eMBErrorCode
eMBEnable( void )
{
eMBErrorCode eStatus = MB_ENOERR;
if( eMBState == STATE_DISABLED )
{
/* Activate the protocol stack. */
pvMBFrameStartCur( );
eMBState = STATE_ENABLED;
}
else
{
eStatus = MB_EILLSTATE;
}
return eStatus;
}
eMBErrorCode
eMBDisable( void )
{
eMBErrorCode eStatus;
if( eMBState == STATE_ENABLED )
{
pvMBFrameStopCur( );
eMBState = STATE_DISABLED;
eStatus = MB_ENOERR;
}
else if( eMBState == STATE_DISABLED )
{
eStatus = MB_ENOERR;
}
else
{
eStatus = MB_EILLSTATE;
}
return eStatus;
}
eMBErrorCode
eMBPoll( void )
{
static uint8_t *ucMBFrame;
static uint8_t ucRcvAddress;
static uint8_t ucFunctionCode;
static uint16_t usLength;
static eMBException eException;
int i;
eMBErrorCode eStatus = MB_ENOERR;
eMBEventType eEvent;
/* Check if the protocol stack is ready. */
if( eMBState != STATE_ENABLED )
{
return MB_EILLSTATE;
}
/* Check if there is a event available. If not return control to caller.
* Otherwise we will handle the event. */
if( xMBPortEventGet( &eEvent ) == true )
{
switch ( eEvent )
{
case EV_READY:
break;
case EV_FRAME_RECEIVED:
eStatus = peMBFrameReceiveCur( &ucRcvAddress, &ucMBFrame, &usLength );
if( eStatus == MB_ENOERR )
{
/* Check if the frame is for us. If not ignore the frame. */
if( ( ucRcvAddress == ucMBAddress ) || ( ucRcvAddress == MB_ADDRESS_BROADCAST ) )
{
( void )xMBPortEventPost( EV_EXECUTE );
}
}
break;
case EV_EXECUTE:
ucFunctionCode = ucMBFrame[MB_PDU_FUNC_OFF];
eException = MB_EX_ILLEGAL_FUNCTION;
for( i = 0; i < CONFIG_MB_FUNC_HANDLERS_MAX; i++ )
{
/* No more function handlers registered. Abort. */
if( xFuncHandlers[i].ucFunctionCode == 0 )
{
break;
}
else if( xFuncHandlers[i].ucFunctionCode == ucFunctionCode )
{
eException = xFuncHandlers[i].pxHandler( ucMBFrame, &usLength );
break;
}
}
/* If the request was not sent to the broadcast address we
* return a reply. */
if( ucRcvAddress != MB_ADDRESS_BROADCAST )
{
if( eException != MB_EX_NONE )
{
/* An exception occured. Build an error frame. */
usLength = 0;
ucMBFrame[usLength++] = ( uint8_t )( ucFunctionCode | MB_FUNC_ERROR );
ucMBFrame[usLength++] = eException;
}
#ifdef CONFIG_MB_ASCII_ENABLED
if( ( eMBCurrentMode == MB_ASCII ) && CONFIG_MB_ASCII_TIMEOUT_WAIT_BEFORE_SEND_MS )
{
vMBPortTimersDelay( CONFIG_MB_ASCII_TIMEOUT_WAIT_BEFORE_SEND_MS );
}
#endif
eStatus = peMBFrameSendCur( ucMBAddress, ucMBFrame, usLength );
}
break;
case EV_FRAME_SENT:
break;
}
}
return MB_ENOERR;
}