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Modbus properties

Use the Modbus properties to configure the mode of operation, master device settings, and slave register settings.

You can set these parameters to configure the Modbus properties.

Communication Interface

Select the type of communication interface the blocks will use for MODBUS® serial communication.

Settings

Default: RS485

Mode

Select the MODBUS mode of operation for the model. This parameter also determines the type of blocks that can be used in the model. For example, in the Master mode, you can use only the Modbus RS485 Master Read and the Modbus RS485 Master Write blocks. Similarly, in the Slave mode, you can use only the Modbus RS485 Slave Read and the Modbus RS485 Slave Write blocks.

Settings

Default: Master

Slave

Slave ID

Enter the unique 8-bit MODBUS slave address or identifier.

Settings

Default: 1

Dependencies

To enable this parameter, set Mode to Slave.

Configure Coils

Select this parameter to configure the starting address and the number of coil registers.

Settings

Default: Selected

Dependencies

To enable this parameter, set Mode to Slave.

Coil Register Parameters

ParameterDescriptionDefault Value

Start address

Starting address of the coil register

Dependencies: To enable this parameter, select Configure Input registers.

0
Quantity

Number of coil registers

Dependencies: To enable this parameter, select Configure Input registers.

1

Configure Discrete Inputs

Select this parameter to configure the starting address and the number of discrete input registers.

Settings

Default: Selected

Dependencies

To enable this parameter, set Mode to Slave.

Discrete Input Register Parameters

ParameterDescriptionDefault Value

Start address

Starting address of the discrete input register

Dependencies: To enable this parameter, select Configure Input registers.

0
Quantity

Number of discrete input registers

Dependencies: To enable this parameter, select Configure Input registers.

1

Configure Holding registers

Select this parameter to configure the starting address and the number of holding registers.

Settings

Default: Selected

Dependencies

To enable this parameter, set Mode to Slave.

Holding Register Parameters

ParameterDescriptionDefault Value

Start address

Starting address of the holding register

Dependencies: To enable this parameter, select Configure Input registers.

0
Quantity

Number of holding registers

Dependencies: To enable this parameter, select Configure Input registers.

1

Configure Input registers

Select this parameter to configure the starting address and the number of input registers.

Settings

Default: Selected

Dependencies

To enable this parameter, set Mode to Slave.

Input Register Parameters

ParameterDescriptionDefault Value

Start address

Starting address of the input register

Dependencies: To enable this parameter, select Configure Input registers.

0
Quantity

Number of input registers

Dependencies: To enable this parameter, select Configure Input registers.

1

Received timeout (ms)

Enter the maximum time in milliseconds to wait for a response from the MODBUS server. If the MODBUS server does not acknowledge the client within the specified time, then the communication is no longer valid.

Settings

Default: 100

Dependencies

To enable this parameter, set Mode to Master.