ModScanner

modscanner is a Python toolkit for discovering, inspecting, scanning, and interacting with Modbus TCP devices.

It provides both a command-line interface and a Python API.

Documentation

• Installation
  • pip
  • Development Installation
• Quick Start
  • Scan Holding Registers
  • Read Coils
  • Read Discrete Inputs
  • Read Input Registers
  • Write a Coil
  • Writing a Holding Register
• Network Discovery
• Command-Line Interface
  • Scan Commands
  • Common Scan Options
  • Typed Register Decoding
  • Write Commands
  • Legacy Command
• Safety
  • Read Operations
  • Authorization
• Scanner API
• Writer API
• Models API
• Transport API
  • Transport Interface
  • PyModbus TCP Transport

Supported Modbus Operations

Function Code	Operation
FC01	Read Coils
FC02	Read Discrete Inputs
FC03	Read Holding Registers
FC04	Read Input Registers
FC05	Write Single Coil
FC06	Write Single Holding Register
FC15	Write Multiple Coils
FC16	Write Multiple Holding Registers

Quick Example

modscanner scan holding \
    --host 192.168.1.10 \
    --device-id 1 \
    --start 0 \
    --count 20

*[!WARNING] Modbus write operations can affect physical equipment. Always verify the target device, address, function, and value before issuing write commands.