1 /*
2 * FreeModbus Libary: A portable Modbus implementation for Modbus ASCII/RTU.
3 * Copyright (c) 2006 Christian Walter <wolti@sil.at>
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: mbfuncholding.c,v 1.12 2007/02/18 23:48:22 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 + 0)
46 #define MB_PDU_FUNC_READ_REGCNT_OFF ( MB_PDU_DATA_OFF + 2 )
47 #define MB_PDU_FUNC_READ_SIZE ( 4 )
48 #define MB_PDU_FUNC_READ_REGCNT_MAX ( 0x007D )
49
50 #define MB_PDU_FUNC_WRITE_ADDR_OFF ( MB_PDU_DATA_OFF + 0)
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 + 0 )
55 #define MB_PDU_FUNC_WRITE_MUL_REGCNT_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_REGCNT_MAX ( 0x0078 )
60
61 #define MB_PDU_FUNC_READWRITE_READ_ADDR_OFF ( MB_PDU_DATA_OFF + 0 )
62 #define MB_PDU_FUNC_READWRITE_READ_REGCNT_OFF ( MB_PDU_DATA_OFF + 2 )
63 #define MB_PDU_FUNC_READWRITE_WRITE_ADDR_OFF ( MB_PDU_DATA_OFF + 4 )
64 #define MB_PDU_FUNC_READWRITE_WRITE_REGCNT_OFF ( MB_PDU_DATA_OFF + 6 )
65 #define MB_PDU_FUNC_READWRITE_BYTECNT_OFF ( MB_PDU_DATA_OFF + 8 )
66 #define MB_PDU_FUNC_READWRITE_WRITE_VALUES_OFF ( MB_PDU_DATA_OFF + 9 )
67 #define MB_PDU_FUNC_READWRITE_SIZE_MIN ( 9 )
68
69 /* ----------------------- Static functions ---------------------------------*/
70 eMBException prveMBError2Exception( eMBErrorCode eErrorCode );
71
72 /* ----------------------- Start implementation -----------------------------*/
73 #if MB_SLAVE_RTU_ENABLED || MB_SLAVE_ASCII_ENABLED || MB_TCP_ENABLED
74
75 #if MB_FUNC_WRITE_HOLDING_ENABLED
76
77 eMBException
eMBFuncWriteHoldingRegister(UCHAR * pucFrame,USHORT * usLen)78 eMBFuncWriteHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
79 {
80 USHORT usRegAddress;
81 eMBException eStatus = MB_EX_NONE;
82 eMBErrorCode eRegStatus;
83
84 if( *usLen == ( MB_PDU_FUNC_WRITE_SIZE + MB_PDU_SIZE_MIN ) )
85 {
86 usRegAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_ADDR_OFF] << 8 );
87 usRegAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_ADDR_OFF + 1] );
88 usRegAddress++;
89
90 /* Make callback to update the value. */
91 eRegStatus = eMBRegHoldingCB( &pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF],
92 usRegAddress, 1, MB_REG_WRITE );
93
94 /* If an error occured convert it into a Modbus exception. */
95 if( eRegStatus != MB_ENOERR )
96 {
97 eStatus = prveMBError2Exception( eRegStatus );
98 }
99 }
100 else
101 {
102 /* Can't be a valid request because the length is incorrect. */
103 eStatus = MB_EX_ILLEGAL_DATA_VALUE;
104 }
105 return eStatus;
106 }
107 #endif
108
109 #if MB_FUNC_WRITE_MULTIPLE_HOLDING_ENABLED > 0
110 eMBException
eMBFuncWriteMultipleHoldingRegister(UCHAR * pucFrame,USHORT * usLen)111 eMBFuncWriteMultipleHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
112 {
113 USHORT usRegAddress;
114 USHORT usRegCount;
115 UCHAR ucRegByteCount;
116
117 eMBException eStatus = MB_EX_NONE;
118 eMBErrorCode eRegStatus;
119
120 if( *usLen >= ( MB_PDU_FUNC_WRITE_MUL_SIZE_MIN + MB_PDU_SIZE_MIN ) )
121 {
122 usRegAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_ADDR_OFF] << 8 );
123 usRegAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_ADDR_OFF + 1] );
124 usRegAddress++;
125
126 usRegCount = ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_REGCNT_OFF] << 8 );
127 usRegCount |= ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_REGCNT_OFF + 1] );
128
129 ucRegByteCount = pucFrame[MB_PDU_FUNC_WRITE_MUL_BYTECNT_OFF];
130
131 if( ( usRegCount >= 1 ) &&
132 ( usRegCount <= MB_PDU_FUNC_WRITE_MUL_REGCNT_MAX ) &&
133 ( ucRegByteCount == ( UCHAR ) ( 2 * usRegCount ) ) )
134 {
135 /* Make callback to update the register values. */
136 eRegStatus =
137 eMBRegHoldingCB( &pucFrame[MB_PDU_FUNC_WRITE_MUL_VALUES_OFF],
138 usRegAddress, usRegCount, MB_REG_WRITE );
139
140 /* If an error occured convert it into a Modbus exception. */
141 if( eRegStatus != MB_ENOERR )
142 {
143 eStatus = prveMBError2Exception( eRegStatus );
144 }
145 else
146 {
147 /* The response contains the function code, the starting
148 * address and the quantity of registers. We reuse the
149 * old values in the buffer because they are still valid.
150 */
151 *usLen = MB_PDU_FUNC_WRITE_MUL_BYTECNT_OFF;
152 }
153 }
154 else
155 {
156 eStatus = MB_EX_ILLEGAL_DATA_VALUE;
157 }
158 }
159 else
160 {
161 /* Can't be a valid request because the length is incorrect. */
162 eStatus = MB_EX_ILLEGAL_DATA_VALUE;
163 }
164 return eStatus;
165 }
166 #endif
167
168 #if MB_FUNC_READ_HOLDING_ENABLED > 0
169
170 eMBException
eMBFuncReadHoldingRegister(UCHAR * pucFrame,USHORT * usLen)171 eMBFuncReadHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
172 {
173 USHORT usRegAddress;
174 USHORT usRegCount;
175 UCHAR *pucFrameCur;
176
177 eMBException eStatus = MB_EX_NONE;
178 eMBErrorCode eRegStatus;
179
180 if( *usLen == ( MB_PDU_FUNC_READ_SIZE + MB_PDU_SIZE_MIN ) )
181 {
182 usRegAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_READ_ADDR_OFF] << 8 );
183 usRegAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_READ_ADDR_OFF + 1] );
184 usRegAddress++;
185
186 usRegCount = ( USHORT )( pucFrame[MB_PDU_FUNC_READ_REGCNT_OFF] << 8 );
187 usRegCount |= ( USHORT )( pucFrame[MB_PDU_FUNC_READ_REGCNT_OFF + 1] );
188
189 /* Check if the number of registers to read is valid. If not
190 * return Modbus illegal data value exception.
191 */
192 if( ( usRegCount >= 1 ) && ( usRegCount <= MB_PDU_FUNC_READ_REGCNT_MAX ) )
193 {
194 /* Set the current PDU data pointer to the beginning. */
195 pucFrameCur = &pucFrame[MB_PDU_FUNC_OFF];
196 *usLen = MB_PDU_FUNC_OFF;
197
198 /* First byte contains the function code. */
199 *pucFrameCur++ = MB_FUNC_READ_HOLDING_REGISTER;
200 *usLen += 1;
201
202 /* Second byte in the response contain the number of bytes. */
203 *pucFrameCur++ = ( UCHAR ) ( usRegCount * 2 );
204 *usLen += 1;
205
206 /* Make callback to fill the buffer. */
207 eRegStatus = eMBRegHoldingCB( pucFrameCur, usRegAddress, usRegCount, MB_REG_READ );
208 /* If an error occured convert it into a Modbus exception. */
209 if( eRegStatus != MB_ENOERR )
210 {
211 eStatus = prveMBError2Exception( eRegStatus );
212 }
213 else
214 {
215 *usLen += usRegCount * 2;
216 }
217 }
218 else
219 {
220 eStatus = MB_EX_ILLEGAL_DATA_VALUE;
221 }
222 }
223 else
224 {
225 /* Can't be a valid request because the length is incorrect. */
226 eStatus = MB_EX_ILLEGAL_DATA_VALUE;
227 }
228 return eStatus;
229 }
230
231 #endif
232
233 #if MB_FUNC_READWRITE_HOLDING_ENABLED > 0
234
235 eMBException
eMBFuncReadWriteMultipleHoldingRegister(UCHAR * pucFrame,USHORT * usLen)236 eMBFuncReadWriteMultipleHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
237 {
238 USHORT usRegReadAddress;
239 USHORT usRegReadCount;
240 USHORT usRegWriteAddress;
241 USHORT usRegWriteCount;
242 UCHAR ucRegWriteByteCount;
243 UCHAR *pucFrameCur;
244
245 eMBException eStatus = MB_EX_NONE;
246 eMBErrorCode eRegStatus;
247
248 if( *usLen >= ( MB_PDU_FUNC_READWRITE_SIZE_MIN + MB_PDU_SIZE_MIN ) )
249 {
250 usRegReadAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_READ_ADDR_OFF] << 8U );
251 usRegReadAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_READ_ADDR_OFF + 1] );
252 usRegReadAddress++;
253
254 usRegReadCount = ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_READ_REGCNT_OFF] << 8U );
255 usRegReadCount |= ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_READ_REGCNT_OFF + 1] );
256
257 usRegWriteAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_WRITE_ADDR_OFF] << 8U );
258 usRegWriteAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_WRITE_ADDR_OFF + 1] );
259 usRegWriteAddress++;
260
261 usRegWriteCount = ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_WRITE_REGCNT_OFF] << 8U );
262 usRegWriteCount |= ( USHORT )( pucFrame[MB_PDU_FUNC_READWRITE_WRITE_REGCNT_OFF + 1] );
263
264 ucRegWriteByteCount = pucFrame[MB_PDU_FUNC_READWRITE_BYTECNT_OFF];
265
266 if( ( usRegReadCount >= 1 ) && ( usRegReadCount <= 0x7D ) &&
267 ( usRegWriteCount >= 1 ) && ( usRegWriteCount <= 0x79 ) &&
268 ( ( 2 * usRegWriteCount ) == ucRegWriteByteCount ) )
269 {
270 /* Make callback to update the register values. */
271 eRegStatus = eMBRegHoldingCB( &pucFrame[MB_PDU_FUNC_READWRITE_WRITE_VALUES_OFF],
272 usRegWriteAddress, usRegWriteCount, MB_REG_WRITE );
273
274 if( eRegStatus == MB_ENOERR )
275 {
276 /* Set the current PDU data pointer to the beginning. */
277 pucFrameCur = &pucFrame[MB_PDU_FUNC_OFF];
278 *usLen = MB_PDU_FUNC_OFF;
279
280 /* First byte contains the function code. */
281 *pucFrameCur++ = MB_FUNC_READWRITE_MULTIPLE_REGISTERS;
282 *usLen += 1;
283
284 /* Second byte in the response contain the number of bytes. */
285 *pucFrameCur++ = ( UCHAR ) ( usRegReadCount * 2 );
286 *usLen += 1;
287
288 /* Make the read callback. */
289 eRegStatus =
290 eMBRegHoldingCB( pucFrameCur, usRegReadAddress, usRegReadCount, MB_REG_READ );
291 if( eRegStatus == MB_ENOERR )
292 {
293 *usLen += 2 * usRegReadCount;
294 }
295 }
296 if( eRegStatus != MB_ENOERR )
297 {
298 eStatus = prveMBError2Exception( eRegStatus );
299 }
300 }
301 else
302 {
303 eStatus = MB_EX_ILLEGAL_DATA_VALUE;
304 }
305 }
306 return eStatus;
307 }
308
309 #endif
310
311 #endif
312
