DUE-ModbusDMA

Table of Contents

• Differences from the original ArduinoModbus
• Examples
• Modbus Library for Arduino
  • Useful resources
  • License

Drop-in replacement for ArduinoModbus, modified to work with DUERS485DMA on Arduino Due.

Differences from the original ArduinoModbus

1. Installation

   • Install this library instead of the original ArduinoModbus.

   • Make sure to also install DUERS485DMA.

2. Include

#include <ArduinoModbus-DUE-DMA.h>

1. Class instantiation

   • Unlike the original library, ModbusRTUServerClass and ModbusRTUClientClass are not pre-instantiated.

   • Empty constructors were removed: you must pass your RS485 instance.

   • Example:

ModbusRTUServerClass modbusServer(RS485);
ModbusRTUClientClass modbusClient(RS485);

1. Everything else is the same

   • API, examples, and functionality follow the official ArduinoModbus library.

   • See the official documentation: https://www.arduino.cc/en/ArduinoModbus/ArduinoModbus

Examples

Check the examples/ folder for usage.

Modbus Library for Arduino

Use Modbus with your Arduino.

Using TCP or RS485 shields, like the MKR 485 Shield. This library depends on the ArduinoRS485 library.

This library is based on libmodbus, modifications were made to the lower level RS485 and TCP layers to use Arduino Serial/RS485 and Client API’s. Then an Arduino friendly API was added on top.

For more information about this library please visit us at https://www.arduino.cc/en/ArduinoModbus/ArduinoModbus

Useful resources

• Modbus - Wikipedia

• Modbus FAQ

License

Copyright (c) 2018 Arduino SA. All rights reserved.

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.

This library 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 Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA