v1.0.0 Released

Modbus Gateway TCP to RTU Bridge

Name: Modbus Gateway
Author: ffutop

A high-performance, configurable gateway written in Go. Connect multiple Modbus TCP masters to a single Serial RTU slave without conflicts.

Download Binary Documentation

Architecture

Serialized concurrency control ensures bus stability.

TCP Masters

Client 1

Client 2

Client 3

TCP/IP

Gateway

Queue Buffer Serializer

RS485

RTU Slave

/dev/ttyUSB0

Protocol Conversion

Seamless conversion between Modbus TCP and Modbus RTU.

Concurrency

Multiple TCP clients supported.

Flexible Config

CLI arguments or YAML files.

RS485 Control

Full support for RTS signal control.

Logging

Configurable levels and targets.

Auto Reconnect

Handles serial port disconnections.

Quick Start

1. Build

bash

git clone https://github.com/ffutop/modbus-gateway.git cd modbus-gateway go build -o modbus-gateway

2. Run

# Listen on port 5020, Device /dev/ttyUSB0

./modbus-gateway -p /dev/ttyUSB0 -s 9600 -P 5020 -v debug

Configuration

Use config.yaml for advanced settings.

# TCP Server
tcp_address: "0.0.0.0"
tcp_port: 502
max_conns: 32

# Serial/RTU
device: "/dev/ttyUSB0"
baud_rate: 19200
data_bits: 8
parity: "N"
stop_bits: 1
timeout: 500ms

# RS485
rs485:
  enabled: true
  delay_rts_before_send: 2ms