The Modbus RTU Slave Communications option emulates the Modbus memory types based on Modicon programmable controllers.

The Modbus RTU Communications option supports writes to the following memory types:

Memory Type	Reference Class	Description
Coils	0X	Discrete Outputs
Holding Registers	4X	Analog Outputs

The Modbus RTU Slave Communications option supports reads from the following memory types:

Memory Type	Reference Class	Description
Coils	0X	Discrete Outputs
Inputs	1X	Discrete Inputs
Input Registers	3X	Analog Inputs
Holding Registers	4X	Analog Outputs

More information

Modbus RTU slave protocol.

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