The Modbus protocol was originally developed for devices connected by serial connection. Over the years however several variants have been used with different connection as well. One popular variant is the Modbus TCP/IP or Modbus TCP. This is a Modbus variant used for communications over TCP/IP networks, connecting over port 502 as a default. It does not require a checksum calculation, as lower layers (TCP/IP) already provide checksum protection. For more detailed information see the Modbus-Wikipedia page.
This application only supports Modbus TCP protocol over TCP/IP. It has been developed with Microsoft C#, and uses Microsoft .NET 4.0. The application consist of 2 files, ModbusTCP.exe and Comp.dll. It does not require installation, you can simply un-compress the files to a folder and run the executable file.
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