diff options
Diffstat (limited to 'apps/modbus/functions/mbfuncinput.c')
-rw-r--r-- | apps/modbus/functions/mbfuncinput.c | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/apps/modbus/functions/mbfuncinput.c b/apps/modbus/functions/mbfuncinput.c new file mode 100644 index 000000000..3061340f6 --- /dev/null +++ b/apps/modbus/functions/mbfuncinput.c @@ -0,0 +1,122 @@ +/* + * 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: mbfuncinput.c,v 1.10 2007/09/12 10:15:56 wolti Exp $ + */ + +/* ----------------------- System includes ----------------------------------*/ +#include <nuttx/config.h> +#include <stdlib.h> +#include <string.h> + +/* ----------------------- Platform includes --------------------------------*/ +#include "port.h" + +/* ----------------------- Modbus includes ----------------------------------*/ +#include <apps/modbus/mb.h> +#include <apps/modbus/mbframe.h> +#include <apps/modbus/mbproto.h> + +/* ----------------------- Defines ------------------------------------------*/ +#define MB_PDU_FUNC_READ_ADDR_OFF ( MB_PDU_DATA_OFF ) +#define MB_PDU_FUNC_READ_REGCNT_OFF ( MB_PDU_DATA_OFF + 2 ) +#define MB_PDU_FUNC_READ_SIZE ( 4 ) +#define MB_PDU_FUNC_READ_REGCNT_MAX ( 0x007D ) + +#define MB_PDU_FUNC_READ_RSP_BYTECNT_OFF ( MB_PDU_DATA_OFF ) + +/* ----------------------- Static functions ---------------------------------*/ +eMBException prveMBError2Exception( eMBErrorCode eErrorCode ); + +/* ----------------------- Start implementation -----------------------------*/ + +#ifdef CONFIG_MB_FUNC_READ_INPUT_ENABLED +eMBException +eMBFuncReadInputRegister( uint8_t * pucFrame, uint16_t * usLen ) +{ + uint16_t usRegAddress; + uint16_t usRegCount; + uint8_t *pucFrameCur; + + eMBException eStatus = MB_EX_NONE; + eMBErrorCode eRegStatus; + + if( *usLen == ( MB_PDU_FUNC_READ_SIZE + MB_PDU_SIZE_MIN ) ) + { + usRegAddress = ( uint16_t )( pucFrame[MB_PDU_FUNC_READ_ADDR_OFF] << 8 ); + usRegAddress |= ( uint16_t )( pucFrame[MB_PDU_FUNC_READ_ADDR_OFF + 1] ); + usRegAddress++; + + usRegCount = ( uint16_t )( pucFrame[MB_PDU_FUNC_READ_REGCNT_OFF] << 8 ); + usRegCount |= ( uint16_t )( pucFrame[MB_PDU_FUNC_READ_REGCNT_OFF + 1] ); + + /* Check if the number of registers to read is valid. If not + * return Modbus illegal data value exception. + */ + if( ( usRegCount >= 1 ) + && ( usRegCount < MB_PDU_FUNC_READ_REGCNT_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_INPUT_REGISTER; + *usLen += 1; + + /* Second byte in the response contain the number of bytes. */ + *pucFrameCur++ = ( uint8_t )( usRegCount * 2 ); + *usLen += 1; + + eRegStatus = + eMBRegInputCB( pucFrameCur, usRegAddress, usRegCount ); + + /* If an error occured convert it into a Modbus exception. */ + if( eRegStatus != MB_ENOERR ) + { + eStatus = prveMBError2Exception( eRegStatus ); + } + else + { + *usLen += usRegCount * 2; + } + } + else + { + eStatus = MB_EX_ILLEGAL_DATA_VALUE; + } + } + else + { + /* Can't be a valid read input register request because the length + * is incorrect. */ + eStatus = MB_EX_ILLEGAL_DATA_VALUE; + } + return eStatus; +} + +#endif |