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