ModbusLink Documentation

Welcome to ModbusLink’s documentation!

ModbusLink is a modern, high-performance Python Modbus library designed for industrial automation, IoT applications, and SCADA systems. Built with modern Python practices, it provides unparalleled ease of use while maintaining enterprise-grade reliability.

Documentation Sections

New to ModbusLink?

⚡ 30-Second Demo

Get up and running with ModbusLink in minutes. Learn the basics and see your first Modbus communication.

Quick Start

🛠️ Installation Guide

Detailed installation guide including system requirements, dependencies, and environment setup.

Installation Guide

Core Features

📖 User Guide

Comprehensive guide covering all features, from basic operations to advanced configurations.

User Guide

🏗️ Architecture Design

Deep dive into ModbusLink’s layered architecture and design principles.

Architecture Design

📚 API Reference

Complete API documentation with detailed class and method descriptions.

API Reference

Real-World Applications

💡 Code Examples

Rich collection of real-world examples covering various industrial application scenarios.

Examples

⚡ Performance Tuning

Performance optimization techniques and concurrent processing best practices.

performance

🔧 Troubleshooting

Common issues solutions and debugging techniques.

Troubleshooting Guide

Key Features

ModbusLink Core Features
Feature	Description	Benefit
🏗️ Layered Architecture	Clean separation of concerns	Easy maintenance & extension
🔌 Universal Transports	TCP, RTU, ASCII support	Works with any Modbus device
⚡ Async Performance	Native asyncio support	Handle 1000+ concurrent connections
🛠️ Developer Experience	Intuitive APIs & full typing	Faster development & fewer bugs
📊 Rich Data Types	float32, int32, strings & more	Handle complex industrial data
🔍 Advanced Debugging	Protocol-level monitoring	Rapid troubleshooting
🖥️ Complete Server	Full server implementation	Build custom Modbus devices
🎯 Production Ready	Comprehensive error handling	Deploy with confidence

Supported Modbus Function Codes

Function Code	Function Name	Description
0x01	Read Coils	Read status of one or more coils (boolean values)
0x02	Read Discrete Inputs	Read status of one or more discrete inputs (read-only boolean values)
0x03	Read Holding Registers	Read values of one or more holding registers (16-bit integers)
0x04	Read Input Registers	Read values of one or more input registers (read-only 16-bit integers)
0x05	Write Single Coil	Write a single coil value to specified address
0x06	Write Single Register	Write a single register value to specified address
0x0F	Write Multiple Coils	Write multiple coil values to consecutive addresses
0x10	Write Multiple Registers	Write multiple register values to consecutive addresses

30-Second Demo

Install ModbusLink

# Install from PyPI
pip install modbuslink

Simple Examples

TCP Client (Ethernet Devices)

from modbuslink import ModbusClient, TcpTransport

# Connect to Modbus TCP device
transport = TcpTransport(host='192.168.1.100', port=502)
client = ModbusClient(transport)

with client:
    # Read temperature sensor
    temp = client.read_float32(slave_id=1, start_address=100)
    print(f"Temperature: {temp:.1f}°C")

    # Control pump switch
    client.write_single_coil(slave_id=1, address=0, value=True)
    print("Pump started!")

Serial Client (RTU Devices)

from modbuslink import ModbusClient, RtuTransport

# Connect to serial device
transport = RtuTransport(port='COM3', baudrate=9600)
client = ModbusClient(transport)

with client:
    # Read flow meter data
    flow = client.read_float32(slave_id=5, start_address=0)
    print(f"Flow rate: {flow:.2f} L/min")

High-Performance Async Operations

import asyncio
from modbuslink import AsyncModbusClient, AsyncTcpTransport

async def read_multiple_plcs():
    """Read from multiple PLCs concurrently"""
    plc1 = AsyncModbusClient(AsyncTcpTransport('192.168.1.10', 502))
    plc2 = AsyncModbusClient(AsyncTcpTransport('192.168.1.11', 502))

    async with plc1, plc2:
        # Concurrent reading
        results = await asyncio.gather(
            plc1.read_holding_registers(1, 0, 10),
            plc2.read_holding_registers(1, 0, 10)
        )
        print(f"PLC1: {results[0]}, PLC2: {results[1]}")

asyncio.run(read_multiple_plcs())

Get Started Now

🚀 Ready to dive in? Head to Installation Guide to install ModbusLink, then check out Quick Start for a detailed tutorial!

Community and Support

📖 GitHub Project

Source code, issue reports, and feature requests

https://github.com/Miraitowa-la/ModbusLink

📦 PyPI Package

Official releases and version history

https://pypi.org/project/modbuslink/