1 /* 2 * FreeModbus Libary: A portable Modbus implementation for Modbus ASCII/RTU. 3 * Copyright (c) 2006 Christian Walter <[email protected]> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote products 15 * derived from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 * 28 * File: $Id: mbframe.h,v 1.9 2006/12/07 22:10:34 wolti Exp $ 29 */ 30 31 #ifndef _MB_FRAME_H 32 #define _MB_FRAME_H 33 34 #ifdef __cplusplus 35 PR_BEGIN_EXTERN_C 36 #endif 37 38 /*! 39 * Constants which defines the format of a modbus frame. The example is 40 * shown for a Modbus RTU/ASCII frame. Note that the Modbus PDU is not 41 * dependent on the underlying transport. 42 * 43 * <code> 44 * <------------------------ MODBUS SERIAL LINE PDU (1) -------------------> 45 * <----------- MODBUS PDU (1') ----------------> 46 * +-----------+---------------+----------------------------+-------------+ 47 * | Address | Function Code | Data | CRC/LRC | 48 * +-----------+---------------+----------------------------+-------------+ 49 * | | | | 50 * (2) (3/2') (3') (4) 51 * 52 * (1) ... MB_SER_PDU_SIZE_MAX = 256 53 * (2) ... MB_SER_PDU_ADDR_OFF = 0 54 * (3) ... MB_SER_PDU_PDU_OFF = 1 55 * (4) ... MB_SER_PDU_SIZE_CRC = 2 56 * 57 * (1') ... MB_PDU_SIZE_MAX = 253 58 * (2') ... MB_PDU_FUNC_OFF = 0 59 * (3') ... MB_PDU_DATA_OFF = 1 60 * </code> 61 */ 62 63 /* ----------------------- Defines ------------------------------------------*/ 64 #define MB_PDU_SIZE_MAX 253 /*!< Maximum size of a PDU. */ 65 #define MB_PDU_SIZE_MIN 1 /*!< Function Code */ 66 #define MB_PDU_FUNC_OFF 0 /*!< Offset of function code in PDU. */ 67 #define MB_PDU_DATA_OFF 1 /*!< Offset for response data in PDU. */ 68 69 /* ----------------------- Prototypes 0-------------------------------------*/ 70 typedef void ( *pvMBFrameStart ) ( void ); 71 72 typedef void ( *pvMBFrameStop ) ( void ); 73 74 typedef eMBErrorCode( *peMBFrameReceive ) ( UCHAR * pucRcvAddress, 75 UCHAR ** pucFrame, 76 USHORT * pusLength ); 77 78 typedef eMBErrorCode( *peMBFrameSend ) ( UCHAR slaveAddress, 79 const UCHAR * pucFrame, 80 USHORT usLength ); 81 82 typedef void( *pvMBFrameClose ) ( void ); 83 84 #ifdef __cplusplus 85 PR_END_EXTERN_C 86 #endif 87 #endif 88