Commercial library by Step Function I/O

A high-performance implementation of the Modbus protocol using Tokio and Rust's async/await syntax.

Features

• Panic-free parsing
• Correctness and compliance to the specification
• Built-in logging and protocol decoding
• Automatic connection management with configurable reconnect strategy
• Scalable performance using Tokio's multi-threaded executor
• TLS is implemented using rustls not openssl
• Model-generated bindings for C, C++, Java, and .NET Core
• Runs on all platforms and operating systems supported by the Tokio runtime:
  • Official support for: Windows x64 and Linux x64, AArch64, ARMv7 and ARMv6
  • Unofficial support: MacOS, PowerPC, MIPS, FreeBSD, and others

Supported Modes

• TCP, RTU (serial), and Modbus security (TLS) with and without X.509 extension containing the user role.
• Client and server

Function Codes

The client and server examples demonstrate simple usage of the API.

The following function codes are supported:

• Read Coils (0x01)
• Read Discrete Inputs (0x02)
• Read Holding Registers (0x03)
• Read Input Registers (0x04)
• Write Single Coil (0x05)
• Write Single Register (0x06)
• Write Multiple Coils (0x0F)
• Write Multiple Registers (0x10)

License

This library is publicly available under a non-commercial / non-production license. Refer to LICENSE.txt for the terms of this non-commercial license.

This software is publicly available, but is not "open source". You must purchase a commercial license to use this software for profit.

Please inquire about commercial licensing on our website:

https://stepfunc.io/contact/

Cargo Features

Default features can be disabled at compile time:

• tls - Build the library with support for TLS (secure Modbus)
• serial - Build the library with support for Modbus RTU and serial ports

Bindings

Bindings in C, C++, java, and .NET Core are available for this library. See the documentation for more details.