/modbus

Modbus TCP, Modbus RTU/TCP, and Modbus RTU/Serial for Java 17+.

Primary LanguageJavaEclipse Public License 2.0EPL-2.0

Maven Central

A modern, performant, easy to use client and server implementation of Modbus TCP, Modbus RTU/TCP, and Modbus RTU/Serial for Java 17+.

Quick Start Examples

Modbus TCP Client

var transport = NettyTcpClientTransport.create(cfg -> {
  cfg.hostname = "172.17.0.2";
  cfg.port = 502;
});

var client = ModbusTcpClient.create(transport);
client.connect();

ReadHoldingRegistersResponse response = client.readHoldingRegisters(
    1,
    new ReadHoldingRegistersRequest(0, 10)
);

System.out.println("Response: " + response);

Modbus RTU/Serial Client

var transport = SerialPortClientTransport.create(cfg -> {
  cfg.serialPort = "/dev/ttyUSB0";
  cfg.baudRate = 115200;
  cfg.dataBits = 8;
  cfg.parity = SerialPort.NO_PARITY;
  cfg.stopBits = SerialPort.ONE_STOP_BIT;
});

var client = ModbusRtuClient.create(transport);
client.connect();

client.readHoldingRegisters(
    1,
    new ReadHoldingRegistersRequest(0, 10)
);

System.out.println("Response: " + response);

Maven

Modbus TCP

<dependency>
    <groupId>com.digitalpetri.modbus</groupId>
    <artifactId>modbus-tcp</artifactId>
    <version>2.0.0-SNAPSHOT</version>
</dependency>

Modbus Serial

<dependency>
    <groupId>com.digitalpetri.modbus</groupId>
    <artifactId>modbus-serial</artifactId>
    <version>2.0.0-SNAPSHOT</version>
</dependency>

Features

Supported Function Codes

Code Function Client Server
0x01 Read Coils
0x02 Read Discrete Inputs
0x03 Read Holding Registers
0x04 Read Input Registers
0x05 Write Single Coil
0x06 Write Single Register
0x0F Write Multiple Coils
0x10 Write Multiple Registers
0x16 Mask Write Register
0x17 Read/Write Multiple Registers
  • raw/custom PDUs on Modbus/TCP
  • broadcast messages on Modbus/RTU
  • pluggable codec implementations
  • pluggable transport implementations

License

Eclipse Public License - v 2.0