FreeMODBUS - A free MODBUS ASCII/RTU and TCP implementation

ModbusTools - Developers of the Modbus Poll tool. Modbus Poll is a Modbus master simulator designed primarily to help developers of Modbus slave devices or others that want to test and simulate the Modbus protocol.
Modpoll Modbus® Polling Tool - Focus Software Engineering have a free Modbus command line utility.
Modbus-IDA - Modus IDA is a non-profit organization which driver further standardization and developments for the Modbus protocol.

FreeMODBUS - A Modbus ASCII/RTU and TCP implementation

FreeMODBUS library and web page maintained by Christian Walter [wolti at sil dot at]
FreeMODBUS is sponsored and provided by embedded solutions
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