Here is a list of all related documentation pages:

What You should know about Modbus	Some Background Technical Information The Protocol Functions How Slave Devices are identified The Register Model and Data Tables Data Encoding Register and Discrete Numbering Scheme The ASCII Protocol The RTU Protocol The MODBUS/TCP Protocol
Installation and Source Code Compilation
Linking your Applications against the Library
How to integrate the Protocol in your Application
Examples
Design Background
License
Support
Notices
Deprecated List