MgsModbus.h

/*
  MgsModbus.h - an Arduino library for a Modbus TCP master and slave.
  V-0.1.1 Copyright (C) 2013  Marco Gerritse
  written and tested with Arduino 1.0
 
    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 3 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, see <http://www.gnu.org/licenses/>.

  For this library the following library is used as start point:
  
    [1] Mudbus.h - an Arduino library for a Modbus TCP slave.
        Copyright (C) 2011  Dee Wykoff
    [2] Function codes 15 & 16 by Martin Pettersson
    
  The following references are used to write this library:
  
    [3] Open Modbus/Tcp specification, Release 1.0, 29 March 1999
        By Andy Swales, Schneider Electric
    [4] Modbus application protocol specification V1.1b3, 26 april 202
        From http:/www.modbus.org
        
  External software used for testing:
  
    [5] modpoll - www.modbusdriver.com/modpoll.html
    [6] ananas - www.tuomio.fi/ananas
    [7] mod_rssim - www.plcsimulator.org 
    [8] modbus master - www.cableone.net/mblansett/
    
  This library use a single block of memory for all modbus data (mbData[] array). The
  same data can be reached via several modbus functions, either via a 16 bit access
  or via an access bit. The length of MbData must at least 1.
  
  For the master the following modbus functions are implemented: 1, 2, 3, 4, 5, 6, 15, 16
  For the slave the following modbus functions are implemented: 1, 2, 3, 4, 5, 6, 15, 16
  
  The internal and external addresses are 0 (zero) based
  
  
  V-0.1.1 2013-06-02
  bugfix
  
  V-0.1.0 2013-03-02
  initinal version
*/


#include "Arduino.h"

#include <SPI.h>
#include <Ethernet.h>

#ifndef MgsModbus_h
#define MgsModbus_h

#define MbDataLen 30 // length of the MdData array
#define MB_PORT 502

enum MB_FC {
  MB_FC_NONE                     = 0,
  MB_FC_READ_COILS               = 1,
  MB_FC_READ_DISCRETE_INPUT      = 2,
  MB_FC_READ_REGISTERS           = 3,
  MB_FC_READ_INPUT_REGISTER      = 4,
  MB_FC_WRITE_COIL               = 5,
  MB_FC_WRITE_REGISTER           = 6,
  MB_FC_WRITE_MULTIPLE_COILS     = 15,
  MB_FC_WRITE_MULTIPLE_REGISTERS = 16
};

class MgsModbus
{
public:
  // general
  MgsModbus();
  word MbData[MbDataLen]; // memory block that holds all the modbus user data
  boolean GetBit(word Number);
  boolean SetBit(word Number,boolean Data); // returns true when the number is in the MbData range
  // modbus master
  void Req(MB_FC FC, word Ref, word Count, word Pos);
  void MbmRun();
  IPAddress remSlaveIP;
  // modbus slave
  void MbsRun();  
  word GetDataLen();
private: 
  // general
  MB_FC SetFC(int fc);
  // modbus master
  uint8_t MbmByteArray[260]; // send and recieve buffer
  MB_FC MbmFC;
  int MbmCounter;
  void MbmProcess();
  word MbmPos;
  word MbmBitCount;
  //modbus slave
  uint8_t MbsByteArray[260]; // send and recieve buffer
  MB_FC MbsFC;
};

#endif