mbframe.h

00001 /* 
00002  * FreeModbus Libary: A portable Modbus implementation for Modbus ASCII/RTU.
00003  * Copyright (c) 2006 Christian Walter <wolti@sil.at>
00004  * All rights reserved.
00005  *
00006  * Redistribution and use in source and binary forms, with or without
00007  * modification, are permitted provided that the following conditions
00008  * are met:
00009  * 1. Redistributions of source code must retain the above copyright
00010  *    notice, this list of conditions and the following disclaimer.
00011  * 2. Redistributions in binary form must reproduce the above copyright
00012  *    notice, this list of conditions and the following disclaimer in the
00013  *    documentation and/or other materials provided with the distribution.
00014  * 3. The name of the author may not be used to endorse or promote products
00015  *    derived from this software without specific prior written permission.
00016  *
00017  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
00018  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
00019  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
00020  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
00021  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
00022  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
00023  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
00024  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
00025  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
00026  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00027  *
00028  * File: $Id: mbframe.h,v 1.9 2006/12/07 22:10:34 wolti Exp $
00029  */
00030 
00031 #ifndef _MB_FRAME_H
00032 #define _MB_FRAME_H
00033 
00034 #ifdef __cplusplus
00035 PR_BEGIN_EXTERN_C
00036 #endif
00037 
00038 /*!
00039  * Constants which defines the format of a modbus frame. The example is
00040  * shown for a Modbus RTU/ASCII frame. Note that the Modbus PDU is not
00041  * dependent on the underlying transport.
00042  *
00043  * <code>
00044  * <------------------------ MODBUS SERIAL LINE PDU (1) ------------------->
00045  *              <----------- MODBUS PDU (1') ---------------->
00046  *  +-----------+---------------+----------------------------+-------------+
00047  *  | Address   | Function Code | Data                       | CRC/LRC     |
00048  *  +-----------+---------------+----------------------------+-------------+
00049  *  |           |               |                                   |
00050  * (2)        (3/2')           (3')                                (4)
00051  *
00052  * (1)  ... MB_SER_PDU_SIZE_MAX = 256
00053  * (2)  ... MB_SER_PDU_ADDR_OFF = 0
00054  * (3)  ... MB_SER_PDU_PDU_OFF  = 1
00055  * (4)  ... MB_SER_PDU_SIZE_CRC = 2
00056  *
00057  * (1') ... MB_PDU_SIZE_MAX     = 253
00058  * (2') ... MB_PDU_FUNC_OFF     = 0
00059  * (3') ... MB_PDU_DATA_OFF     = 1
00060  * </code>
00061  */
00062 
00063 /* ----------------------- Defines ------------------------------------------*/
00064 #define MB_PDU_SIZE_MAX     253 /*!< Maximum size of a PDU. */
00065 #define MB_PDU_SIZE_MIN     1   /*!< Function Code */
00066 #define MB_PDU_FUNC_OFF     0   /*!< Offset of function code in PDU. */
00067 #define MB_PDU_DATA_OFF     1   /*!< Offset for response data in PDU. */
00068 
00069 /* ----------------------- Prototypes  0-------------------------------------*/
00070 typedef void    ( *pvMBFrameStart ) ( void );
00071 
00072 typedef void    ( *pvMBFrameStop ) ( void );
00073 
00074 typedef eMBErrorCode( *peMBFrameReceive ) ( UCHAR * pucRcvAddress,
00075                                             UCHAR ** pucFrame,
00076                                             USHORT * pusLength );
00077 
00078 typedef eMBErrorCode( *peMBFrameSend ) ( UCHAR slaveAddress,
00079                                          const UCHAR * pucFrame,
00080                                          USHORT usLength );
00081 
00082 typedef void( *pvMBFrameClose ) ( void );
00083 
00084 #ifdef __cplusplus
00085 PR_END_EXTERN_C
00086 #endif
00087 #endif