Modbus

1. NModbus

1.1 下载地址

        https://github.com/NModbus/NModbus

1.2 C#ModBus Tcp的学习及Master的实现

        https://www.cnblogs.com/pandefu/p/10824331.html

2. easyModbus

2.1 官网

        http://easymodbustcp.net/en/

2.2 代码例程

        Codesamples EasyModbusTCP.NET

.NET: Modbus-TCP  Client Simple Read and Write operations 

namespace ModbusClientApplication
{
    class Program
    {
        public static void Main(string[] args)
        {
            ModbusClient modbusClient = new ModbusClient("190.201.100.100", 502);    //Ip-Address and Port of Modbus-TCP-Server
            modbusClient.Connect();                                                    //Connect to Server
            modbusClient.WriteMultipleCoils(4, new bool[] {true, true, true, true, true, true, true, true, true, true});    //Write Coils starting with Address 5
            bool[] readCoils = modbusClient.ReadCoils(9,10);                        //Read 10 Coils from Server, starting with address 10
            int[] readHoldingRegisters = modbusClient.ReadHoldingRegisters(0,10);    //Read 10 Holding Registers from Server, starting with Address 1

            // Console Output
            for (int i = 0; i < readCoils.Length; i++)
                Console.WriteLine("Value of Coil " + (9 + i + 1) + " " + readCoils[i].ToString());
                        
            for (int i = 0; i < readHoldingRegisters.Length; i++)
                Console.WriteLine("Value of HoldingRegister " + (i + 1) + " "+ readHoldingRegisters[i].ToString());            
            modbusClient.Disconnect();                                                //Disconnect from Server
            Console.Write("Press any key to continue . . . ");
            Console.ReadKey(true);
        }
    }
}

Modbus-TCP Server which publishes the values on change to a MQTT-Broker

   class Program
    {
        static void Main(string[] args)
        {
            Program application = new Program();
            application.startServer();

        }

        public void startServer()
        {
            EasyModbus.ModbusServer modbusServer = new EasyModbus.ModbusServer();
            modbusServer.MqttRootTopic = "examplemodbusserver";
            modbusServer.MqttBrokerAddress = "www.mqtt-dashboard.com";
            modbusServer.Listen();
            modbusServer.holdingRegistersChanged += new EasyModbus.ModbusServer.HoldingRegistersChanged(holdingRegistersChanged);
            Console.ReadKey();
            
            modbusServer.StopListening();
        }

        public void holdingRegistersChanged(int startingAddress, int quantity)
        {
            Console.WriteLine(startingAddress);
            Console.WriteLine(quantity);
        }
    }