What Does Modbus Mean?

Modbus is an application layer data protocol present at Level 7 of the Open System Interconnection (OSI) model of communication. It provides a connection between servers and clients located on different devices and networks. This serial communication protocol was introduced in 1979 by Modicon as a messaging structure between devices connected through buses or networks.


Techopedia Explains Modbus

Modbus is an open-source protocol, which means the application is available online free of charge for downloading and no license fee is changed for using it. A number of versions of Modbus are available, including Modbus RTU (based on serial communication like RS485 and RS232), Modbus ASCII and Modbus TCP, which is the Modbus RTU protocol embedded into TCP/IP packets. A number of devices connected serially in a network can communicate via the Modbus application protocol. A device requesting information is called a Modbus master, whereas a device providing data is a Modbus slave. A typical network has only one master and up to 247 slave devices.


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Margaret Rouse

Margaret Rouse is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical, business audience. Over the past twenty years her explanations have appeared on TechTarget websites and she's been cited as an authority in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine and Discovery Magazine.Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages. If you have a suggestion for a new definition or how to improve a technical explanation, please email Margaret or contact her…