1 /*
2  * FreeModbus Libary: A portable Modbus implementation for Modbus ASCII/RTU.
3  * Copyright (C) 2013 Armink <armink.ztl@gmail.com>
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: mbfuncdisc_m.c,v 1.60 2013/10/15 8:48:20 Armink Add Master Functions  Exp $
29  */
30 
31 
32 
33 /* ----------------------- System includes ----------------------------------*/
34 #include "stdlib.h"
35 #include "string.h"
36 
37 /* ----------------------- Platform includes --------------------------------*/
38 #include "port.h"
39 
40 /* ----------------------- Modbus includes ----------------------------------*/
41 #include "mb_m.h"
42 #include "mbframe.h"
43 #include "mbproto.h"
44 #include "mbconfig.h"
45 
46 /* ----------------------- Defines ------------------------------------------*/
47 #define MB_PDU_REQ_READ_ADDR_OFF            ( MB_PDU_DATA_OFF + 0 )
48 #define MB_PDU_REQ_READ_DISCCNT_OFF         ( MB_PDU_DATA_OFF + 2 )
49 #define MB_PDU_REQ_READ_SIZE                ( 4 )
50 #define MB_PDU_FUNC_READ_DISCCNT_OFF        ( MB_PDU_DATA_OFF + 0 )
51 #define MB_PDU_FUNC_READ_VALUES_OFF         ( MB_PDU_DATA_OFF + 1 )
52 #define MB_PDU_FUNC_READ_SIZE_MIN           ( 1 )
53 
54 /* ----------------------- Static functions ---------------------------------*/
55 eMBException    prveMBError2Exception( eMBErrorCode eErrorCode );
56 
57 /* ----------------------- Start implementation -----------------------------*/
58 #if MB_MASTER_RTU_ENABLED || MB_MASTER_ASCII_ENABLED || MB_MASTER_TCP_ENABLED
59 
60 #if MB_FUNC_READ_DISCRETE_INPUTS_ENABLED
61 
62 /**
63  * This function will request read discrete inputs.
64  *
65  * @param ucSndAddr salve address
66  * @param usDiscreteAddr discrete start address
67  * @param usNDiscreteIn discrete total number
68  * @param lTimeOut timeout (-1 will waiting forever)
69  *
70  * @return error code
71  */
72 eMBMasterReqErrCode
eMBMasterReqReadDiscreteInputs(UCHAR ucSndAddr,USHORT usDiscreteAddr,USHORT usNDiscreteIn,LONG lTimeOut)73 eMBMasterReqReadDiscreteInputs( UCHAR ucSndAddr, USHORT usDiscreteAddr, USHORT usNDiscreteIn, LONG lTimeOut )
74 {
75     UCHAR                 *ucMBFrame;
76     eMBMasterReqErrCode    eErrStatus = MB_MRE_NO_ERR;
77 
78     if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
79     else if ( xMBMasterRunResTake( lTimeOut ) == FALSE ) eErrStatus = MB_MRE_MASTER_BUSY;
80     else
81     {
82         vMBMasterGetPDUSndBuf(&ucMBFrame);
83         vMBMasterSetDestAddress(ucSndAddr);
84         ucMBFrame[MB_PDU_FUNC_OFF]                 = MB_FUNC_READ_DISCRETE_INPUTS;
85         ucMBFrame[MB_PDU_REQ_READ_ADDR_OFF]        = usDiscreteAddr >> 8;
86         ucMBFrame[MB_PDU_REQ_READ_ADDR_OFF + 1]    = usDiscreteAddr;
87         ucMBFrame[MB_PDU_REQ_READ_DISCCNT_OFF ]    = usNDiscreteIn >> 8;
88         ucMBFrame[MB_PDU_REQ_READ_DISCCNT_OFF + 1] = usNDiscreteIn;
89         vMBMasterSetPDUSndLength( MB_PDU_SIZE_MIN + MB_PDU_REQ_READ_SIZE );
90         ( void ) xMBMasterPortEventPost( EV_MASTER_FRAME_TRANSMIT );
91         eErrStatus = eMBMasterWaitRequestFinish( );
92     }
93     return eErrStatus;
94 }
95 
96 eMBException
eMBMasterFuncReadDiscreteInputs(UCHAR * pucFrame,USHORT * usLen)97 eMBMasterFuncReadDiscreteInputs( UCHAR * pucFrame, USHORT * usLen )
98 {
99     USHORT          usRegAddress;
100     USHORT          usDiscreteCnt;
101     UCHAR           ucNBytes;
102     UCHAR          *ucMBFrame;
103 
104     eMBException    eStatus = MB_EX_NONE;
105     eMBErrorCode    eRegStatus;
106 
107     /* If this request is broadcast, and it's read mode. This request don't need execute. */
108     if ( xMBMasterRequestIsBroadcast() )
109     {
110         eStatus = MB_EX_NONE;
111     }
112     else if( *usLen >= MB_PDU_SIZE_MIN + MB_PDU_FUNC_READ_SIZE_MIN )
113     {
114         vMBMasterGetPDUSndBuf(&ucMBFrame);
115         usRegAddress = ( USHORT )( ucMBFrame[MB_PDU_REQ_READ_ADDR_OFF] << 8 );
116         usRegAddress |= ( USHORT )( ucMBFrame[MB_PDU_REQ_READ_ADDR_OFF + 1] );
117         usRegAddress++;
118 
119         usDiscreteCnt = ( USHORT )( ucMBFrame[MB_PDU_REQ_READ_DISCCNT_OFF] << 8 );
120         usDiscreteCnt |= ( USHORT )( ucMBFrame[MB_PDU_REQ_READ_DISCCNT_OFF + 1] );
121 
122         /* Test if the quantity of coils is a multiple of 8. If not last
123          * byte is only partially field with unused coils set to zero. */
124         if( ( usDiscreteCnt & 0x0007 ) != 0 )
125         {
126             ucNBytes = ( UCHAR )( usDiscreteCnt / 8 + 1 );
127         }
128         else
129         {
130             ucNBytes = ( UCHAR )( usDiscreteCnt / 8 );
131         }
132 
133         /* Check if the number of registers to read is valid. If not
134          * return Modbus illegal data value exception.
135          */
136         if ((usDiscreteCnt >= 1) && ucNBytes == pucFrame[MB_PDU_FUNC_READ_DISCCNT_OFF])
137         {
138             /* Make callback to fill the buffer. */
139             eRegStatus = eMBMasterRegDiscreteCB( &pucFrame[MB_PDU_FUNC_READ_VALUES_OFF], usRegAddress, usDiscreteCnt );
140 
141             /* If an error occured convert it into a Modbus exception. */
142             if( eRegStatus != MB_ENOERR )
143             {
144                 eStatus = prveMBError2Exception( eRegStatus );
145             }
146         }
147         else
148         {
149             eStatus = MB_EX_ILLEGAL_DATA_VALUE;
150         }
151     }
152     else
153     {
154         /* Can't be a valid read coil register request because the length
155          * is incorrect. */
156         eStatus = MB_EX_ILLEGAL_DATA_VALUE;
157     }
158     return eStatus;
159 }
160 
161 #endif
162 #endif // #if MB_SERIAL_MASTER_RTU_ENABLED || MB_SERIAL_MASTER_ASCII_ENABLED || MB_MASTER_TCP_ENABLED
163