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: mbfunccoils.c,v 1.8 2007/02/18 23:47:16 wolti Exp $ 29 */ 30 31 /* ----------------------- System includes ----------------------------------*/ 32 #include "stdlib.h" 33 #include "string.h" 34 35 /* ----------------------- Platform includes --------------------------------*/ 36 #include "port.h" 37 38 /* ----------------------- Modbus includes ----------------------------------*/ 39 #include "mb.h" 40 #include "mbframe.h" 41 #include "mbproto.h" 42 #include "mbconfig.h" 43 44 /* ----------------------- Defines ------------------------------------------*/ 45 #define MB_PDU_FUNC_READ_ADDR_OFF ( MB_PDU_DATA_OFF ) 46 #define MB_PDU_FUNC_READ_COILCNT_OFF ( MB_PDU_DATA_OFF + 2 ) 47 #define MB_PDU_FUNC_READ_SIZE ( 4 ) 48 #define MB_PDU_FUNC_READ_COILCNT_MAX ( 0x07D0 ) 49 50 #define MB_PDU_FUNC_WRITE_ADDR_OFF ( MB_PDU_DATA_OFF ) 51 #define MB_PDU_FUNC_WRITE_VALUE_OFF ( MB_PDU_DATA_OFF + 2 ) 52 #define MB_PDU_FUNC_WRITE_SIZE ( 4 ) 53 54 #define MB_PDU_FUNC_WRITE_MUL_ADDR_OFF ( MB_PDU_DATA_OFF ) 55 #define MB_PDU_FUNC_WRITE_MUL_COILCNT_OFF ( MB_PDU_DATA_OFF + 2 ) 56 #define MB_PDU_FUNC_WRITE_MUL_BYTECNT_OFF ( MB_PDU_DATA_OFF + 4 ) 57 #define MB_PDU_FUNC_WRITE_MUL_VALUES_OFF ( MB_PDU_DATA_OFF + 5 ) 58 #define MB_PDU_FUNC_WRITE_MUL_SIZE_MIN ( 5 ) 59 #define MB_PDU_FUNC_WRITE_MUL_COILCNT_MAX ( 0x07B0 ) 60 61 /* ----------------------- Static functions ---------------------------------*/ 62 eMBException prveMBError2Exception( eMBErrorCode eErrorCode ); 63 64 /* ----------------------- Start implementation -----------------------------*/ 65 66 #if MB_FUNC_READ_COILS_ENABLED > 0 67 68 eMBException 69 eMBFuncReadCoils( UCHAR * pucFrame, USHORT * usLen ) 70 { 71 USHORT usRegAddress; 72 USHORT usCoilCount; 73 UCHAR ucNBytes; 74 UCHAR *pucFrameCur; 75 76 eMBException eStatus = MB_EX_NONE; 77 eMBErrorCode eRegStatus; 78 79 if( *usLen == ( MB_PDU_FUNC_READ_SIZE + MB_PDU_SIZE_MIN ) ) 80 { 81 usRegAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_READ_ADDR_OFF] << 8 ); 82 usRegAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_READ_ADDR_OFF + 1] ); 83 usRegAddress++; 84 85 usCoilCount = ( USHORT )( pucFrame[MB_PDU_FUNC_READ_COILCNT_OFF] << 8 ); 86 usCoilCount |= ( USHORT )( pucFrame[MB_PDU_FUNC_READ_COILCNT_OFF + 1] ); 87 88 /* Check if the number of registers to read is valid. If not 89 * return Modbus illegal data value exception. 90 */ 91 if( ( usCoilCount >= 1 ) && 92 ( usCoilCount < MB_PDU_FUNC_READ_COILCNT_MAX ) ) 93 { 94 /* Set the current PDU data pointer to the beginning. */ 95 pucFrameCur = &pucFrame[MB_PDU_FUNC_OFF]; 96 *usLen = MB_PDU_FUNC_OFF; 97 98 /* First byte contains the function code. */ 99 *pucFrameCur++ = MB_FUNC_READ_COILS; 100 *usLen += 1; 101 102 /* Test if the quantity of coils is a multiple of 8. If not last 103 * byte is only partially field with unused coils set to zero. */ 104 if( ( usCoilCount & 0x0007 ) != 0 ) 105 { 106 ucNBytes = ( UCHAR )( usCoilCount / 8 + 1 ); 107 } 108 else 109 { 110 ucNBytes = ( UCHAR )( usCoilCount / 8 ); 111 } 112 *pucFrameCur++ = ucNBytes; 113 *usLen += 1; 114 115 eRegStatus = 116 eMBRegCoilsCB( pucFrameCur, usRegAddress, usCoilCount, 117 MB_REG_READ ); 118 119 /* If an error occured convert it into a Modbus exception. */ 120 if( eRegStatus != MB_ENOERR ) 121 { 122 eStatus = prveMBError2Exception( eRegStatus ); 123 } 124 else 125 { 126 /* The response contains the function code, the starting address 127 * and the quantity of registers. We reuse the old values in the 128 * buffer because they are still valid. */ 129 *usLen += ucNBytes;; 130 } 131 } 132 else 133 { 134 eStatus = MB_EX_ILLEGAL_DATA_VALUE; 135 } 136 } 137 else 138 { 139 /* Can't be a valid read coil register request because the length 140 * is incorrect. */ 141 eStatus = MB_EX_ILLEGAL_DATA_VALUE; 142 } 143 return eStatus; 144 } 145 #endif 146 147 #if MB_FUNC_WRITE_COIL_ENABLED > 0 148 eMBException 149 eMBFuncWriteCoil( UCHAR * pucFrame, USHORT * usLen ) 150 { 151 USHORT usRegAddress; 152 UCHAR ucBuf[2]; 153 154 eMBException eStatus = MB_EX_NONE; 155 eMBErrorCode eRegStatus; 156 157 if( *usLen == ( MB_PDU_FUNC_WRITE_SIZE + MB_PDU_SIZE_MIN ) ) 158 { 159 usRegAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_ADDR_OFF] << 8 ); 160 usRegAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_ADDR_OFF + 1] ); 161 usRegAddress++; 162 163 if( ( pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF + 1] == 0x00 ) && 164 ( ( pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF] == 0xFF ) || 165 ( pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF] == 0x00 ) ) ) 166 { 167 ucBuf[1] = 0; 168 if( pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF] == 0xFF ) 169 { 170 ucBuf[0] = 1; 171 } 172 else 173 { 174 ucBuf[0] = 0; 175 } 176 eRegStatus = 177 eMBRegCoilsCB( &ucBuf[0], usRegAddress, 1, MB_REG_WRITE ); 178 179 /* If an error occured convert it into a Modbus exception. */ 180 if( eRegStatus != MB_ENOERR ) 181 { 182 eStatus = prveMBError2Exception( eRegStatus ); 183 } 184 } 185 else 186 { 187 eStatus = MB_EX_ILLEGAL_DATA_VALUE; 188 } 189 } 190 else 191 { 192 /* Can't be a valid write coil register request because the length 193 * is incorrect. */ 194 eStatus = MB_EX_ILLEGAL_DATA_VALUE; 195 } 196 return eStatus; 197 } 198 199 #endif 200 201 #if MB_FUNC_WRITE_MULTIPLE_COILS_ENABLED > 0 202 eMBException 203 eMBFuncWriteMultipleCoils( UCHAR * pucFrame, USHORT * usLen ) 204 { 205 USHORT usRegAddress; 206 USHORT usCoilCnt; 207 UCHAR ucByteCount; 208 UCHAR ucByteCountVerify; 209 210 eMBException eStatus = MB_EX_NONE; 211 eMBErrorCode eRegStatus; 212 213 if( *usLen > ( MB_PDU_FUNC_WRITE_SIZE + MB_PDU_SIZE_MIN ) ) 214 { 215 usRegAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_ADDR_OFF] << 8 ); 216 usRegAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_ADDR_OFF + 1] ); 217 usRegAddress++; 218 219 usCoilCnt = ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_COILCNT_OFF] << 8 ); 220 usCoilCnt |= ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_COILCNT_OFF + 1] ); 221 222 ucByteCount = pucFrame[MB_PDU_FUNC_WRITE_MUL_BYTECNT_OFF]; 223 224 /* Compute the number of expected bytes in the request. */ 225 if( ( usCoilCnt & 0x0007 ) != 0 ) 226 { 227 ucByteCountVerify = ( UCHAR )( usCoilCnt / 8 + 1 ); 228 } 229 else 230 { 231 ucByteCountVerify = ( UCHAR )( usCoilCnt / 8 ); 232 } 233 234 if( ( usCoilCnt >= 1 ) && 235 ( usCoilCnt <= MB_PDU_FUNC_WRITE_MUL_COILCNT_MAX ) && 236 ( ucByteCountVerify == ucByteCount ) ) 237 { 238 eRegStatus = 239 eMBRegCoilsCB( &pucFrame[MB_PDU_FUNC_WRITE_MUL_VALUES_OFF], 240 usRegAddress, usCoilCnt, MB_REG_WRITE ); 241 242 /* If an error occured convert it into a Modbus exception. */ 243 if( eRegStatus != MB_ENOERR ) 244 { 245 eStatus = prveMBError2Exception( eRegStatus ); 246 } 247 else 248 { 249 /* The response contains the function code, the starting address 250 * and the quantity of registers. We reuse the old values in the 251 * buffer because they are still valid. */ 252 *usLen = MB_PDU_FUNC_WRITE_MUL_BYTECNT_OFF; 253 } 254 } 255 else 256 { 257 eStatus = MB_EX_ILLEGAL_DATA_VALUE; 258 } 259 } 260 else 261 { 262 /* Can't be a valid write coil register request because the length 263 * is incorrect. */ 264 eStatus = MB_EX_ILLEGAL_DATA_VALUE; 265 } 266 return eStatus; 267 } 268 269 #endif 270