PyModbus
lastmod 2026-11-10created 2025-11-042 edits
pymodbus is a library that implements the Modbus protocol in Python, supporting both the client (master) and server (slave) sides. It handles Modbus RTU and ASCII for serial communication as well as Modbus TCP for Ethernet, provides function codes for reading and writing coils and registers as methods, and supports both synchronous and asyncio-based asynchronous modes. It is used to communicate with industrial equipment such as PLCs, power meters, and inverters, or to build virtual devices for testing.
A full modbus protocol written in python