Top 3 modbus-protocol open source projects

Rust implementation of Modbus with idiomatic bindings for C, C++, .NET, and Java

A native node addon to calcalate and verify CRC16 values, adopted by MODBUS agreement

Most complete Modbus library for Arduino. A library that allows your Arduino board to communicate via Modbus protocol, acting as a master, slave or both. Supports network transport (Modbus TCP) and Serial line/RS-485 (Modbus RTU). Supports Modbus TCP Security for ESP8266/ESP32.