ModbusTcpClient

Description

The ModbusTcpClient object implements a Modbus TCP client which communicates with Modbus slaves (servers) via TCP network connections.

› Inherits:

ModbusClient

Overview

Properties

Methods

Signals

Enumerations

Properties

lowDelay

This property holds whether to optimize the underlying TCP/IP socket for low latency by setting the TCP_NODELAY option and disabling Nagle’s algorithm.

This property was introduced in InCore 2.5.

› Type:

Boolean

› Default:

false

› Signal:

lowDelayChanged()

› Attributes:

Writable

networkAddress

This property holds the host address of the Modbus TCP server which to connect to.

› Type:

String

› Default:

127.0.0.1

› Signal:

networkAddressChanged()

› Attributes:

Writable

networkPort

This property holds the network port of the Modbus TCP server which to connect to.

› Type:

SignedInteger

› Default:

502

› Signal:

networkPortChanged()

› Attributes:

Writable

Example

import InCore.Foundation 2.5
import InCore.Modbus 2.5

Application {

    name: "Modbus TCP client example"

    ModbusTcpClient {
        // set address to connect to
        networkAddress: "192.168.10.19"

        // change retry and timeout configuration
        numberOfRetries: 1
        timeout: 500

        ModbusSlave {
            address: 1

            // define Modbus register for temperature
            ModbusRegister {
                id: temperature
                type: ModbusRegister.Input
                address: 1
                onDataChanged: console.log("Temperature", data)
            }

            // define special Modbus register device name stored as string
            ModbusRegister {
                type: ModbusRegister.Holding
                address: 0x1000
                count: 8
                dataType: ModbusRegister.String
                onDataChanged: console.log("Device name", data)
            }

            // read all registers every 50 ms
            Polling on registers { interval: 50 }
        }

        // print information message when connected
        onConnected: console.log("Connected to Modbus TCP slave")

        // print error message if something goes wrong
        onErrorOccurred: console.log(errorString)
    }
}