Modbus TCP I/O Mapping

Prerequisites

A Modbus TCP channel must exist.

Configure the Modbus TCP IOScanner

To configure a Modbus TCP IOScanner, proceed as follows:

Step	Action
1	In the Devices tree, double-click the protocol manager. Result: The configuration window is displayed.
2	Select the IOScanner I/O Mapping tab: NOTE: For more information on Health Bit, refer to IOS_GETHEALTH function. NOTE: For more information on Enable Channels, refer to IOS_CONTROLCHANNEL function.
3	Select the Bus cycle task in the list: Use parent bus cycle setting (by default), MAST NOTE: The Bus cycle task parameter inside the I/O mapping editor of the device that contains the Modbus TCP IOScanner defines the task responsible for the refresh of the I/O images (%QW, %IW). These I/O images correspond to the Modbus request sent to the Modbus slaves and the health bits.
4	Double-click in a cell of the Variable column to open a text field. Enter the name of a variable or click the browse button [...] and chose a variable with the Input Assistant.

Configure a Modbus TCP Slave Device I/O Mapping

To configure a Modbus TCP slave device I/O Mapping, proceed as follows:

Step	Action
1	In the Devices tree, double-click a Modbus TCP slave device. Result: Its configuration window is displayed.
2	Select the ModbusTCPSlave I/O Mapping tab.
3	Select the Bus cycle task in the list: Use parent bus cycle setting (by default), MAST NOTE: The Bus cycle task parameter inside the I/O mapping editor of the device that contains the Modbus TCP IOScanner defines the task responsible for the refresh of the I/O images (%QW, %IW). These I/O images correspond to the Modbus request sent to the Modbus slaves and the health bits.
4	Double-click in a cell of the Variable column to open a text field. Enter the name of a variable or click the browse button [...] and chose a variable with the Input Assistant.