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- Create a unique TCPIP Port object for each field device.
- Set the Connection Type property to TCP.
- Enter the field device's connection parameters in the Host Address and Port properties.
- Set the Port Control property to Maintain Control.
- Advise at least one OPC register item in your client application, or alias list, and poll it at least once to establish the TCP connection.
- On the field device, set item 486, Modem AT Call Enable, to "Always Connected No Dial".
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