/* * FreeModbus Libary: AVR Demo Application * Copyright (C) 2006 Christian Walter * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * * File: $Id$ */ /* ----------------------- Modbus includes ----------------------------------*/ #include "mb.h" #include "mbutils.h" /* ----------------------- Defines ------------------------------------------*/ #define REG_COILS_START 1000 #define REG_COILS_SIZE 16 /* ----------------------- Static variables ---------------------------------*/ static unsigned char ucRegCoilsBuf[REG_COILS_SIZE / 8]; /* ----------------------- Start implementation -----------------------------*/ int main( void ) { /* Select either ASCII or RTU Mode. */ ( void )eMBInit( MB_RTU, 0x0A, 0, 9600, MB_PAR_EVEN ); /* Enable the Modbus Protocol Stack. */ ( void )eMBEnable( ); for( ;; ) { /* Call the main polling loop of the Modbus protocol stack. */ ( void )eMBPoll( ); } } eMBErrorCode eMBRegCoilsCB( UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNCoils, eMBRegisterMode eMode ) { eMBErrorCode eStatus = MB_ENOERR; short iNCoils = ( short )usNCoils; unsigned short usBitOffset; /* Check if we have registers mapped at this block. */ if( ( usAddress >= REG_COILS_START ) && ( usAddress + usNCoils <= REG_COILS_START + REG_COILS_SIZE ) ) { usBitOffset = ( unsigned short )( usAddress - REG_COILS_START ); switch ( eMode ) { /* Read current values and pass to protocol stack. */ case MB_REG_READ: while( iNCoils > 0 ) { *pucRegBuffer++ = xMBUtilGetBits( ucRegCoilsBuf, usBitOffset, ( unsigned char )( iNCoils > 8 ? 8 : iNCoils ) ); iNCoils -= 8; usBitOffset += 8; } break; /* Update current register values. */ case MB_REG_WRITE: while( iNCoils > 0 ) { xMBUtilSetBits( ucRegCoilsBuf, usBitOffset, ( unsigned char )( iNCoils > 8 ? 8 : iNCoils ), *pucRegBuffer++ ); iNCoils -= 8; } break; } } else { eStatus = MB_ENOREG; } return eStatus; } eMBErrorCode eMBRegInputCB( UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNRegs ) { return MB_ENOREG; } eMBErrorCode eMBRegHoldingCB( UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNRegs, eMBRegisterMode eMode ) { return MB_ENOREG; } eMBErrorCode eMBRegDiscreteCB( UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNDiscrete ) { return MB_ENOREG; }