Latest revision as of 09:17, 30 March 2020

What is MODBUS

Modbus protocol is a general language applied to electronic controller. Through this protocol, the controllers can communicate with each other, the controllers can communicate with other devices through the network (such as Ethernet). It has become a general industrial standard. With it, the control equipment produced by different manufacturers can be connected into an industrial network for centralized monitoring.

Modbus protocol defines a message structure that the controller can understand and use, and does not need to know what kind of network they are communicating through. It describes the process of a controller requesting access to other devices, how to respond to requests from other devices, and how to detect errors and record them.

The standard Modbus protocol consists of the following two communication modes:

1. Ethernet

   The corresponding communication mode is Modbus TCP/IP.

2. Asynchronous serial transmission (various media such as wired RS-232/422/485; optical fiber, wireless, etc.)

   The corresponding communication mode is Modbus RTU or MODBUS ASCII. The original Modbus interface ran on RS-232, but most later Modbus implementations used RS-485 because it allowed longer distances, higher speeds and the possibility of a true multi-drop network.

For more information, please refer to http://www.modbus.org/.

How to connect a MODBUS device to DeviceOn Server

You can connect to the DeviceOn server through RS485 and network.For detailed configuration, please refer to:

http://ess-wiki.advantech.com.tw/view/Modbus_Handler_2.0_Real_Application_Case