kopia lustrzana https://github.com/espressif/esp-idf
575 wiersze
19 KiB
C
575 wiersze
19 KiB
C
/*
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* FreeModbus Libary: A portable Modbus implementation for Modbus ASCII/RTU.
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* Copyright (c) 2006 Christian Walter <wolti@sil.at>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. The name of the author may not be used to endorse or promote products
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* derived from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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* File: $Id: mbascii.c,v 1.17 2010/06/06 13:47:07 wolti Exp $
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*/
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/* ----------------------- System includes ----------------------------------*/
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#include "stdlib.h"
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#include "string.h"
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/* ----------------------- Platform includes --------------------------------*/
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#include "port.h"
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/* ----------------------- Modbus includes ----------------------------------*/
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#include "mb_m.h"
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#include "mbconfig.h"
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#include "mbascii.h"
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#include "mbframe.h"
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#include "mbcrc.h"
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#include "mbport.h"
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#if MB_MASTER_ASCII_ENABLED > 0
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/* ----------------------- Defines ------------------------------------------*/
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#define MB_TIMER_TICS_PER_MS 20UL
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/* ----------------------- Type definitions ---------------------------------*/
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typedef enum
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{
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STATE_M_RX_INIT, /*!< Receiver is in initial state. */
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STATE_M_RX_IDLE, /*!< Receiver is in idle state. */
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STATE_M_RX_RCV, /*!< Frame is beeing received. */
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STATE_M_RX_WAIT_EOF, /*!< Wait for End of Frame. */
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STATE_M_RX_ERROR, /*!< If the frame is invalid. */
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} eMBMasterAsciiRcvState;
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typedef enum
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{
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STATE_M_TX_IDLE, /*!< Transmitter is in idle state. */
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STATE_M_TX_START, /*!< Starting transmission (':' sent). */
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STATE_M_TX_DATA, /*!< Sending of data (Address, Data, LRC). */
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STATE_M_TX_END, /*!< End of transmission. */
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STATE_M_TX_NOTIFY, /*!< Notify sender that the frame has been sent. */
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STATE_M_TX_XFWR, /*!< Transmitter is in transfer finish and wait receive state. */
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} eMBMasterAsciiSndState;
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typedef enum
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{
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BYTE_HIGH_NIBBLE, /*!< Character for high nibble of byte. */
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BYTE_LOW_NIBBLE /*!< Character for low nibble of byte. */
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} eMBBytePos;
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/* ----------------------- Shared values -----------------------------------*/
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/* These Modbus values are shared in ASCII mode*/
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extern volatile UCHAR ucMasterRcvBuf[];
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extern volatile UCHAR ucMasterSndBuf[];
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extern volatile eMBMasterTimerMode eMasterCurTimerMode;
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/* ----------------------- Static functions ---------------------------------*/
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static UCHAR prvucMBCHAR2BIN( UCHAR ucCharacter );
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static UCHAR prvucMBBIN2CHAR( UCHAR ucByte );
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static UCHAR prvucMBLRC( UCHAR * pucFrame, USHORT usLen );
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/* ----------------------- Static variables ---------------------------------*/
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static volatile eMBMasterAsciiSndState eSndState;
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static volatile eMBMasterAsciiRcvState eRcvState;
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static volatile UCHAR *ucMasterASCIIRcvBuf = ucMasterRcvBuf;
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static volatile UCHAR *ucMasterASCIISndBuf = ucMasterSndBuf;
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static volatile USHORT usMasterRcvBufferPos;
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static volatile eMBBytePos eBytePos;
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static volatile UCHAR *pucMasterSndBufferCur;
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static volatile USHORT usMasterSndBufferCount;
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static volatile UCHAR ucLRC;
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static volatile UCHAR ucMBLFCharacter;
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/* ----------------------- Start implementation -----------------------------*/
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eMBErrorCode
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eMBMasterASCIIInit( UCHAR ucPort, ULONG ulBaudRate, eMBParity eParity )
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{
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eMBErrorCode eStatus = MB_ENOERR;
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ENTER_CRITICAL_SECTION( );
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ucMBLFCharacter = MB_ASCII_DEFAULT_LF;
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if( xMBMasterPortSerialInit( ucPort, ulBaudRate, MB_ASCII_BITS_PER_SYMB, eParity ) != TRUE )
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{
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eStatus = MB_EPORTERR;
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}
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else if( xMBMasterPortTimersInit( MB_ASCII_TIMEOUT_MS * MB_TIMER_TICS_PER_MS ) != TRUE )
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{
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eStatus = MB_EPORTERR;
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}
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EXIT_CRITICAL_SECTION( );
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return eStatus;
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}
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void
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eMBMasterASCIIStart( void )
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{
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ENTER_CRITICAL_SECTION( );
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eRcvState = STATE_M_RX_IDLE;
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vMBMasterPortSerialEnable( TRUE, FALSE );
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vMBMasterPortTimersT35Enable( );
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EXIT_CRITICAL_SECTION( );
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}
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void
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eMBMasterASCIIStop( void )
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{
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ENTER_CRITICAL_SECTION( );
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vMBMasterPortSerialEnable( FALSE, FALSE );
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vMBMasterPortTimersDisable( );
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EXIT_CRITICAL_SECTION( );
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}
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eMBErrorCode
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eMBMasterASCIIReceive( UCHAR * pucRcvAddress, UCHAR ** pucFrame, USHORT * pusLength )
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{
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eMBErrorCode eStatus = MB_ENOERR;
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ENTER_CRITICAL_SECTION( );
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assert( usMasterRcvBufferPos < MB_SER_PDU_SIZE_MAX );
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/* Length and CRC check */
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if( ( usMasterRcvBufferPos >= MB_ASCII_SER_PDU_SIZE_MIN )
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&& ( prvucMBLRC( ( UCHAR * ) ucMasterASCIIRcvBuf, usMasterRcvBufferPos ) == 0 ) )
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{
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/* Save the address field. All frames are passed to the upper layed
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* and the decision if a frame is used is done there.
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*/
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*pucRcvAddress = ucMasterASCIIRcvBuf[MB_SER_PDU_ADDR_OFF];
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/* Total length of Modbus-PDU is Modbus-Serial-Line-PDU minus
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* size of address field and CRC checksum.
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*/
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*pusLength = ( USHORT )( usMasterRcvBufferPos - MB_SER_PDU_PDU_OFF - MB_SER_PDU_SIZE_LRC );
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/* Return the start of the Modbus PDU to the caller. */
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*pucFrame = ( UCHAR * ) & ucMasterASCIIRcvBuf[MB_SER_PDU_PDU_OFF];
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}
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else
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{
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eStatus = MB_EIO;
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}
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EXIT_CRITICAL_SECTION( );
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return eStatus;
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}
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eMBErrorCode
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eMBMasterASCIISend( UCHAR ucSlaveAddress, const UCHAR * pucFrame, USHORT usLength )
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{
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eMBErrorCode eStatus = MB_ENOERR;
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UCHAR usLRC;
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if ( ucSlaveAddress > MB_MASTER_TOTAL_SLAVE_NUM ) return MB_EINVAL;
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ENTER_CRITICAL_SECTION( );
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/* Check if the receiver is still in idle state. If not we where too
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* slow with processing the received frame and the master sent another
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* frame on the network. We have to abort sending the frame.
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*/
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if(eRcvState == STATE_M_RX_IDLE)
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{
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/* First byte before the Modbus-PDU is the slave address. */
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pucMasterSndBufferCur = ( UCHAR * ) pucFrame - 1;
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usMasterSndBufferCount = 1;
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/* Now copy the Modbus-PDU into the Modbus-Serial-Line-PDU. */
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pucMasterSndBufferCur[MB_SER_PDU_ADDR_OFF] = ucSlaveAddress;
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usMasterSndBufferCount += usLength;
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/* Calculate LRC checksum for Modbus-Serial-Line-PDU. */
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usLRC = prvucMBLRC( ( UCHAR * ) pucMasterSndBufferCur, usMasterSndBufferCount );
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ucMasterASCIISndBuf[usMasterSndBufferCount++] = usLRC;
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/* Activate the transmitter. */
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eSndState = STATE_M_TX_START;
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vMBMasterPortSerialEnable( FALSE, TRUE );
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}
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else
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{
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eStatus = MB_EIO;
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}
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EXIT_CRITICAL_SECTION( );
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return eStatus;
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}
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BOOL
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xMBMasterASCIIReceiveFSM( void )
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{
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BOOL xNeedPoll = FALSE;
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UCHAR ucByte;
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UCHAR ucResult;
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assert(( eSndState == STATE_M_TX_IDLE ) || ( eSndState == STATE_M_TX_XFWR ));
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/* Always read the character. */
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xNeedPoll = xMBMasterPortSerialGetByte( ( CHAR * ) & ucByte );
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switch ( eRcvState )
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{
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/* If we have received a character in the init state we have to
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* wait until the frame is finished.
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*/
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case STATE_M_RX_INIT:
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vMBMasterPortTimersT35Enable( );
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break;
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/* In the error state we wait until all characters in the
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* damaged frame are transmitted.
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*/
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case STATE_M_RX_ERROR:
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vMBMasterPortTimersRespondTimeoutEnable( );
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break;
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/* In the idle state we wait for a new character. If a character
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* is received the t1.5 and t3.5 timers are started and the
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* receiver is in the state STATE_RX_RECEIVE and disable early
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* the timer of respond timeout .
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*/
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case STATE_M_RX_IDLE:
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/* Waiting for the start of frame character during respond timeout */
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vMBMasterPortTimersRespondTimeoutEnable( );
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if( ucByte == ':' )
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{
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/* Reset the input buffers to store the frame in receive state. */
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usMasterRcvBufferPos = 0;
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eBytePos = BYTE_HIGH_NIBBLE;
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eRcvState = STATE_M_RX_RCV;
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}
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eSndState = STATE_M_TX_IDLE;
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break;
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/* A new character is received. If the character is a ':' the input
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* buffer is cleared. A CR-character signals the end of the data
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* block. Other characters are part of the data block and their
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* ASCII value is converted back to a binary representation.
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*/
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case STATE_M_RX_RCV:
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/* Enable timer timeout. */
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vMBMasterPortTimersT35Enable( );
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if( ucByte == ':' )
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{
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/* Empty receive buffer. */
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eBytePos = BYTE_HIGH_NIBBLE;
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usMasterRcvBufferPos = 0;
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}
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else if( ucByte == MB_ASCII_DEFAULT_CR )
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{
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eRcvState = STATE_M_RX_WAIT_EOF;
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}
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else
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{
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ucResult = prvucMBCHAR2BIN( ucByte );
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switch ( eBytePos )
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{
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/* High nibble of the byte comes first. We check for
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* a buffer overflow here. */
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case BYTE_HIGH_NIBBLE:
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if( usMasterRcvBufferPos < MB_SER_PDU_SIZE_MAX )
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{
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ucMasterASCIIRcvBuf[usMasterRcvBufferPos] = ( UCHAR )( ucResult << 4 );
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eBytePos = BYTE_LOW_NIBBLE;
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break;
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}
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else
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{
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/* not handled in Modbus specification but seems
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* a resonable implementation. */
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eRcvState = STATE_M_RX_ERROR;
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/* Disable previously activated timer because of error state. */
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vMBPortTimersDisable( );
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}
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break;
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case BYTE_LOW_NIBBLE:
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ucMasterASCIIRcvBuf[usMasterRcvBufferPos] |= ucResult;
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usMasterRcvBufferPos++;
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eBytePos = BYTE_HIGH_NIBBLE;
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break;
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}
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}
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break;
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case STATE_M_RX_WAIT_EOF:
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if( ucByte == ucMBLFCharacter )
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{
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/* Disable character timeout timer because all characters are
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* received. */
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vMBMasterPortTimersDisable( );
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/* Receiver is again in idle state. */
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eRcvState = STATE_M_RX_IDLE;
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/* Notify the caller of eMBMasterASCIIReceive that a new frame
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* was received. */
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(void)xMBMasterPortEventPost( EV_MASTER_FRAME_RECEIVED );
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xNeedPoll = FALSE;
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}
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else if( ucByte == ':' )
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{
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/* Start of frame character received but last message is not completed.
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* Empty receive buffer and back to receive state. */
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eBytePos = BYTE_HIGH_NIBBLE;
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usMasterRcvBufferPos = 0;
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eRcvState = STATE_M_RX_IDLE;
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/* Enable timer for respond timeout and wait for next frame. */
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vMBMasterPortTimersRespondTimeoutEnable( );
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}
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else
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{
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/* Frame is not okay. Delete entire frame. */
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eRcvState = STATE_M_RX_IDLE;
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}
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break;
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}
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return xNeedPoll;
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}
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BOOL
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xMBMasterASCIITransmitFSM( void )
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{
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BOOL xNeedPoll = TRUE;
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UCHAR ucByte;
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BOOL xFrameIsBroadcast = FALSE;
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assert( eRcvState == STATE_M_RX_IDLE );
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switch ( eSndState )
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{
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/* We should not get a transmitter event if the transmitter is in
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* idle state. */
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case STATE_M_TX_XFWR:
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break;
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/* We should not get a transmitter event if the transmitter is in
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* idle state. */
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case STATE_M_TX_IDLE:
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break;
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/* Start of transmission. The start of a frame is defined by sending
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* the character ':'. */
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case STATE_M_TX_START:
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ucByte = ':';
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xMBMasterPortSerialPutByte( ( CHAR )ucByte );
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eSndState = STATE_M_TX_DATA;
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eBytePos = BYTE_HIGH_NIBBLE;
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break;
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/* Send the data block. Each data byte is encoded as a character hex
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* stream with the high nibble sent first and the low nibble sent
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* last. If all data bytes are exhausted we send a '\r' character
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* to end the transmission. */
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case STATE_M_TX_DATA:
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if( usMasterSndBufferCount > 0 )
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{
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switch ( eBytePos )
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{
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case BYTE_HIGH_NIBBLE:
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ucByte = prvucMBBIN2CHAR( ( UCHAR )( *pucMasterSndBufferCur >> 4 ) );
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xMBMasterPortSerialPutByte( ( CHAR ) ucByte );
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eBytePos = BYTE_LOW_NIBBLE;
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break;
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case BYTE_LOW_NIBBLE:
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ucByte = prvucMBBIN2CHAR( ( UCHAR )( *pucMasterSndBufferCur & 0x0F ) );
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xMBMasterPortSerialPutByte( ( CHAR )ucByte );
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pucMasterSndBufferCur++;
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eBytePos = BYTE_HIGH_NIBBLE;
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usMasterSndBufferCount--;
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break;
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}
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}
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else
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{
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xMBMasterPortSerialPutByte( MB_ASCII_DEFAULT_CR );
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eSndState = STATE_M_TX_END;
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}
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break;
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/* Finish the frame by sending a LF character. */
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case STATE_M_TX_END:
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xMBMasterPortSerialPutByte( ( CHAR )ucMBLFCharacter );
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/* We need another state to make sure that the CR character has
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* been sent. */
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eSndState = STATE_M_TX_NOTIFY;
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break;
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/* Notify the task which called eMBMasterASCIISend that the frame has
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* been sent. */
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case STATE_M_TX_NOTIFY:
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xFrameIsBroadcast = ( ucMasterASCIISndBuf[MB_SER_PDU_ADDR_OFF] == MB_ADDRESS_BROADCAST ) ? TRUE : FALSE;
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vMBMasterRequestSetType( xFrameIsBroadcast );
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eSndState = STATE_M_TX_XFWR;
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/* If the frame is broadcast ,master will enable timer of convert delay,
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* else master will enable timer of respond timeout. */
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if ( xFrameIsBroadcast == TRUE )
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{
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vMBMasterPortTimersConvertDelayEnable( );
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}
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else
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{
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vMBMasterPortTimersRespondTimeoutEnable( );
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}
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xNeedPoll = FALSE;
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break;
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}
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return xNeedPoll;
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}
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BOOL
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xMBMasterASCIITimerT1SExpired( void )
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{
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BOOL xNeedPoll = FALSE;
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switch ( eRcvState )
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{
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/* Timer t35 expired. Startup phase is finished. */
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case STATE_M_RX_INIT:
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xNeedPoll = xMBMasterPortEventPost(EV_MASTER_READY);
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ESP_EARLY_LOGI("xMBMasterASCIITimerT1SExpired", "RX_INIT_EXPIRED");
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break;
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/* Start of message is not received during respond timeout.
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* Process error. */
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case STATE_M_RX_IDLE:
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eRcvState = STATE_M_RX_ERROR;
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break;
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/* A recieve timeout expired and no any new character received.
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* Wait for respond time and go to error state to inform listener about error */
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case STATE_M_RX_RCV:
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eRcvState = STATE_M_RX_ERROR;
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break;
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/* An error occured while receiving the frame. */
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case STATE_M_RX_ERROR:
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vMBMasterSetErrorType(EV_ERROR_RECEIVE_DATA);
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xNeedPoll = xMBMasterPortEventPost( EV_MASTER_ERROR_PROCESS );
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break;
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/* If we have a timeout we go back to the idle state and wait for
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* the next frame.
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*/
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case STATE_M_RX_WAIT_EOF:
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eRcvState = STATE_M_RX_IDLE;
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break;
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default:
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assert( 0 );
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break;
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}
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eRcvState = STATE_M_RX_IDLE;
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|
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switch (eSndState)
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{
|
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/* A frame was send finish and convert delay or respond timeout expired.
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* If the frame is broadcast,The master will idle,and if the frame is not
|
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* broadcast.*/
|
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case STATE_M_TX_XFWR:
|
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if ( xMBMasterRequestIsBroadcast( ) == FALSE ) {
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vMBMasterSetErrorType(EV_ERROR_RESPOND_TIMEOUT);
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xNeedPoll = xMBMasterPortEventPost(EV_MASTER_ERROR_PROCESS);
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}
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break;
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|
|
/* Function called in an illegal state. */
|
|
default:
|
|
assert( ( eSndState == STATE_M_TX_START ) || ( eSndState == STATE_M_TX_IDLE )
|
|
|| ( eSndState == STATE_M_TX_DATA ) || ( eSndState == STATE_M_TX_END )
|
|
|| ( eSndState == STATE_M_TX_NOTIFY ) );
|
|
break;
|
|
}
|
|
eSndState = STATE_M_TX_IDLE;
|
|
|
|
vMBMasterPortTimersDisable( );
|
|
/* If timer mode is convert delay, the master event then turns EV_MASTER_EXECUTE status. */
|
|
if (xMBMasterGetCurTimerMode() == MB_TMODE_CONVERT_DELAY) {
|
|
xNeedPoll = xMBMasterPortEventPost( EV_MASTER_EXECUTE );
|
|
}
|
|
|
|
vMBMasterPortTimersDisable( );
|
|
|
|
/* no context switch required. */
|
|
return xNeedPoll;
|
|
}
|
|
|
|
static UCHAR
|
|
prvucMBCHAR2BIN( UCHAR ucCharacter )
|
|
{
|
|
if( ( ucCharacter >= '0' ) && ( ucCharacter <= '9' ) )
|
|
{
|
|
return ( UCHAR )( ucCharacter - '0' );
|
|
}
|
|
else if( ( ucCharacter >= 'A' ) && ( ucCharacter <= 'F' ) )
|
|
{
|
|
return ( UCHAR )( ucCharacter - 'A' + 0x0A );
|
|
}
|
|
else
|
|
{
|
|
return 0xFF;
|
|
}
|
|
}
|
|
|
|
static UCHAR
|
|
prvucMBBIN2CHAR( UCHAR ucByte )
|
|
{
|
|
if( ucByte <= 0x09 )
|
|
{
|
|
return ( UCHAR )( '0' + ucByte );
|
|
}
|
|
else if( ( ucByte >= 0x0A ) && ( ucByte <= 0x0F ) )
|
|
{
|
|
return ( UCHAR )( ucByte - 0x0A + 'A' );
|
|
}
|
|
else
|
|
{
|
|
/* Programming error. */
|
|
assert( 0 );
|
|
}
|
|
return '0';
|
|
}
|
|
|
|
static UCHAR
|
|
prvucMBLRC( UCHAR * pucFrame, USHORT usLen )
|
|
{
|
|
UCHAR ucLRC = 0; /* LRC char initialized */
|
|
|
|
while( usLen-- )
|
|
{
|
|
ucLRC += *pucFrame++; /* Add buffer byte without carry */
|
|
}
|
|
|
|
/* Return twos complement */
|
|
ucLRC = ( UCHAR ) ( -( ( CHAR ) ucLRC ) );
|
|
return ucLRC;
|
|
}
|
|
|
|
#endif
|