Diff: mbfunccoils.cpp

Revision:

0:274eb57e1df3

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbfunccoils.cpp	Sun Aug 22 16:34:20 2010 +0000
@@ -0,0 +1,270 @@
+/* 
+ * FreeModbus Libary: A portable Modbus implementation for Modbus ASCII/RTU.
+ * Copyright (c) 2006 Christian Walter <wolti@sil.at>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * File: $Id: mbfunccoils.c,v 1.8 2007/02/18 23:47:16 wolti Exp $
+ */
+
+/* ----------------------- System includes ----------------------------------*/
+#include "stdlib.h"
+#include "string.h"
+
+/* ----------------------- Platform includes --------------------------------*/
+#include "port.h"
+
+/* ----------------------- Modbus includes ----------------------------------*/
+#include "mb.h"
+#include "mbframe.h"
+#include "mbproto.h"
+#include "mbconfig.h"
+
+/* ----------------------- Defines ------------------------------------------*/
+#define MB_PDU_FUNC_READ_ADDR_OFF           ( MB_PDU_DATA_OFF )
+#define MB_PDU_FUNC_READ_COILCNT_OFF        ( MB_PDU_DATA_OFF + 2 )
+#define MB_PDU_FUNC_READ_SIZE               ( 4 )
+#define MB_PDU_FUNC_READ_COILCNT_MAX        ( 0x07D0 )
+
+#define MB_PDU_FUNC_WRITE_ADDR_OFF          ( MB_PDU_DATA_OFF )
+#define MB_PDU_FUNC_WRITE_VALUE_OFF         ( MB_PDU_DATA_OFF + 2 )
+#define MB_PDU_FUNC_WRITE_SIZE              ( 4 )
+
+#define MB_PDU_FUNC_WRITE_MUL_ADDR_OFF      ( MB_PDU_DATA_OFF )
+#define MB_PDU_FUNC_WRITE_MUL_COILCNT_OFF   ( MB_PDU_DATA_OFF + 2 )
+#define MB_PDU_FUNC_WRITE_MUL_BYTECNT_OFF   ( MB_PDU_DATA_OFF + 4 )
+#define MB_PDU_FUNC_WRITE_MUL_VALUES_OFF    ( MB_PDU_DATA_OFF + 5 )
+#define MB_PDU_FUNC_WRITE_MUL_SIZE_MIN      ( 5 )
+#define MB_PDU_FUNC_WRITE_MUL_COILCNT_MAX   ( 0x07B0 )
+
+/* ----------------------- Static functions ---------------------------------*/
+eMBException    prveMBError2Exception( eMBErrorCode eErrorCode );
+
+/* ----------------------- Start implementation -----------------------------*/
+
+#if MB_FUNC_READ_COILS_ENABLED > 0
+
+eMBException
+eMBFuncReadCoils( UCHAR * pucFrame, USHORT * usLen )
+{
+    USHORT          usRegAddress;
+    USHORT          usCoilCount;
+    UCHAR           ucNBytes;
+    UCHAR          *pucFrameCur;
+
+    eMBException    eStatus = MB_EX_NONE;
+    eMBErrorCode    eRegStatus;
+
+    if( *usLen == ( MB_PDU_FUNC_READ_SIZE + MB_PDU_SIZE_MIN ) )
+    {
+        usRegAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_READ_ADDR_OFF] << 8 );
+        usRegAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_READ_ADDR_OFF + 1] );
+        usRegAddress++;
+
+        usCoilCount = ( USHORT )( pucFrame[MB_PDU_FUNC_READ_COILCNT_OFF] << 8 );
+        usCoilCount |= ( USHORT )( pucFrame[MB_PDU_FUNC_READ_COILCNT_OFF + 1] );
+
+        /* Check if the number of registers to read is valid. If not
+         * return Modbus illegal data value exception. 
+         */
+        if( ( usCoilCount >= 1 ) &&
+            ( usCoilCount < MB_PDU_FUNC_READ_COILCNT_MAX ) )
+        {
+            /* Set the current PDU data pointer to the beginning. */
+            pucFrameCur = &pucFrame[MB_PDU_FUNC_OFF];
+            *usLen = MB_PDU_FUNC_OFF;
+
+            /* First byte contains the function code. */
+            *pucFrameCur++ = MB_FUNC_READ_COILS;
+            *usLen += 1;
+
+            /* Test if the quantity of coils is a multiple of 8. If not last
+             * byte is only partially field with unused coils set to zero. */
+            if( ( usCoilCount & 0x0007 ) != 0 )
+            {
+                ucNBytes = ( UCHAR )( usCoilCount / 8 + 1 );
+            }
+            else
+            {
+                ucNBytes = ( UCHAR )( usCoilCount / 8 );
+            }
+            *pucFrameCur++ = ucNBytes;
+            *usLen += 1;
+
+            eRegStatus =
+                eMBRegCoilsCB( pucFrameCur, usRegAddress, usCoilCount,
+                               MB_REG_READ );
+
+            /* If an error occured convert it into a Modbus exception. */
+            if( eRegStatus != MB_ENOERR )
+            {
+                eStatus = prveMBError2Exception( eRegStatus );
+            }
+            else
+            {
+                /* The response contains the function code, the starting address
+                 * and the quantity of registers. We reuse the old values in the 
+                 * buffer because they are still valid. */
+                *usLen += ucNBytes;;
+            }
+        }
+        else
+        {
+            eStatus = MB_EX_ILLEGAL_DATA_VALUE;
+        }
+    }
+    else
+    {
+        /* Can't be a valid read coil register request because the length
+         * is incorrect. */
+        eStatus = MB_EX_ILLEGAL_DATA_VALUE;
+    }
+    return eStatus;
+}
+
+#if MB_FUNC_WRITE_COIL_ENABLED > 0
+eMBException
+eMBFuncWriteCoil( UCHAR * pucFrame, USHORT * usLen )
+{
+    USHORT          usRegAddress;
+    UCHAR           ucBuf[2];
+
+    eMBException    eStatus = MB_EX_NONE;
+    eMBErrorCode    eRegStatus;
+
+    if( *usLen == ( MB_PDU_FUNC_WRITE_SIZE + MB_PDU_SIZE_MIN ) )
+    {
+        usRegAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_ADDR_OFF] << 8 );
+        usRegAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_ADDR_OFF + 1] );
+        usRegAddress++;
+
+        if( ( pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF + 1] == 0x00 ) &&
+            ( ( pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF] == 0xFF ) ||
+              ( pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF] == 0x00 ) ) )
+        {
+            ucBuf[1] = 0;
+            if( pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF] == 0xFF )
+            {
+                ucBuf[0] = 1;
+            }
+            else
+            {
+                ucBuf[0] = 0;
+            }
+            eRegStatus =
+                eMBRegCoilsCB( &ucBuf[0], usRegAddress, 1, MB_REG_WRITE );
+
+            /* If an error occured convert it into a Modbus exception. */
+            if( eRegStatus != MB_ENOERR )
+            {
+                eStatus = prveMBError2Exception( eRegStatus );
+            }
+        }
+        else
+        {
+            eStatus = MB_EX_ILLEGAL_DATA_VALUE;
+        }
+    }
+    else
+    {
+        /* Can't be a valid write coil register request because the length
+         * is incorrect. */
+        eStatus = MB_EX_ILLEGAL_DATA_VALUE;
+    }
+    return eStatus;
+}
+
+#endif
+
+#if MB_FUNC_WRITE_MULTIPLE_COILS_ENABLED > 0
+eMBException
+eMBFuncWriteMultipleCoils( UCHAR * pucFrame, USHORT * usLen )
+{
+    USHORT          usRegAddress;
+    USHORT          usCoilCnt;
+    UCHAR           ucByteCount;
+    UCHAR           ucByteCountVerify;
+
+    eMBException    eStatus = MB_EX_NONE;
+    eMBErrorCode    eRegStatus;
+
+    if( *usLen > ( MB_PDU_FUNC_WRITE_SIZE + MB_PDU_SIZE_MIN ) )
+    {
+        usRegAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_ADDR_OFF] << 8 );
+        usRegAddress |= ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_ADDR_OFF + 1] );
+        usRegAddress++;
+
+        usCoilCnt = ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_COILCNT_OFF] << 8 );
+        usCoilCnt |= ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_COILCNT_OFF + 1] );
+
+        ucByteCount = pucFrame[MB_PDU_FUNC_WRITE_MUL_BYTECNT_OFF];
+
+        /* Compute the number of expected bytes in the request. */
+        if( ( usCoilCnt & 0x0007 ) != 0 )
+        {
+            ucByteCountVerify = ( UCHAR )( usCoilCnt / 8 + 1 );
+        }
+        else
+        {
+            ucByteCountVerify = ( UCHAR )( usCoilCnt / 8 );
+        }
+
+        if( ( usCoilCnt >= 1 ) &&
+            ( usCoilCnt <= MB_PDU_FUNC_WRITE_MUL_COILCNT_MAX ) &&
+            ( ucByteCountVerify == ucByteCount ) )
+        {
+            eRegStatus =
+                eMBRegCoilsCB( &pucFrame[MB_PDU_FUNC_WRITE_MUL_VALUES_OFF],
+                               usRegAddress, usCoilCnt, MB_REG_WRITE );
+
+            /* If an error occured convert it into a Modbus exception. */
+            if( eRegStatus != MB_ENOERR )
+            {
+                eStatus = prveMBError2Exception( eRegStatus );
+            }
+            else
+            {
+                /* The response contains the function code, the starting address
+                 * and the quantity of registers. We reuse the old values in the 
+                 * buffer because they are still valid. */
+                *usLen = MB_PDU_FUNC_WRITE_MUL_BYTECNT_OFF;
+            }
+        }
+        else
+        {
+            eStatus = MB_EX_ILLEGAL_DATA_VALUE;
+        }
+    }
+    else
+    {
+        /* Can't be a valid write coil register request because the length
+         * is incorrect. */
+        eStatus = MB_EX_ILLEGAL_DATA_VALUE;
+    }
+    return eStatus;
+}
+
+#endif
+
+#endif