ModbusRx

A Reactive Modbus implementation based on NModbus4

Using ModbusRx

What is ModbusRx?

ModbusRx has been developed using the NModbus4 library as a base ModbusRx is a reactive implementation of the Modbus protocol. It is designed to be used with the Reactive Extensions library (Rx.NET) and provides a simple and easy to use API for reading and writing Modbus data. a. Modbus/RTU Master/Slave b. Modbus/ASCII Master/Slave c. Modbus/TCP Master/Slave d. Modbus/UDP Master/Slave

NModbus Master API

Create Master, Set Retries, Set ReadTimeout, Master.Read, Update to UI, Master.Dispose, CreateRtu, CreateAscii, CreateIp(TcpClient), CreateIp(UdpClient), Retries [Property], ReadTimeout[Property], Master.ReadCoils, Master.ReadInputs, Master.ReadHoldingRegisters, Master.ReadInputRegisters, WriteSingleCoil, WriteSingleRegisterSet Retries

CreateRtu

RTU master create connection to serial port.

CreateAscii

Ascii master create connection to serial port.

CreateIp(TcpClient)

IP master create connection to TCP.

CreateIp(UdpClient)

IP master create connection to UDP.

ReadTimeout[Property]

Gets or sets the number of milliseconds before a timeout occurs when a read operation does not finish.

ReadCoils

Read coils status.

ReadInputs

Read input status.

ReadHoldingRegisters

Read holding registers value.

ReadInputRegisters

Read input registers value.

WriteSingleCoil

Write a coil value.

WriteSingleRegister

Write a holding register value.

NModbus Slave API

Create Slave

CreateRtu

Create a RTU slave connection.

CreateAscii

Create an Ascii slave connection.

CreateTcp

Create a TCP slave connection. Max value of TCP slave from master is 50.

CreateUdp

Create a UDP slave connection.

CreateDefaultDataStore

Create memory space in Datastore. AI and AO’s Datastore set to 0. DI and DO’s Datastore set to false. For each memory default size is 65535 and range is 1 to 65535.

ModbusSlaveRequestReceived[event]

Occurs when a modbus slave receives a request. You can disassemble request packet and set particular action here.

DataStoreWrittenTo[event]

Occurs when a slave receive write AO or DO command to Datastore from master via a Modbus command. Address starts from 1 to 65535.

Remarks “slave” is defined by ModbusSlave and create slave connection. For example: To create TCP slave connection, syntax is = Create.TcpIpSlave("127.0.0.1").

Listen

Slave starts listening for requests.

CoilDiscretes[DO data array]

Data array of DO values. Address starts from 1 to 65535.

InputDiscretes [DI data array]

Data array of DI values. You can store DI values in the array. Address starts from 1 to 65535.

HoldingRegisters [AO data array]

Data array of AO values. Address starts from 1 to 65535.

InputRegisters [AI data array]

Data array of AI values. You can store AI values in the array. Address starts from 1 to 65535.

Common API

Dispose

Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.