Overview
The “TCP/UDP Realtime” Function (TF6311) offers direct access to network cards from the real-time environment. Access can be either from the PLC (61131-3) or C++.
The following protocols are supported:
- TCP/IP
- UDP/IP
- ARP / Ping
This section describes the concept of interfaces as API. An introduction is provided by means of sample programs.
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Regardless of the protocol, the communication between the project using the protocol and TwinCAT is realized with a pair of interfaces:
- An Interface Pointer provides support for sending data and establishing connections etc.
- The implementation of a receiver interface provides feedback for the project in the form of events or data, based on callbacks.
The communication partner of these interface pairs is a “TCP/UDP RT” TcCom object, which is instantiated and configured with the network card.
- Depending on the protocol, the Quickstarts provide a good introduction.
- The configuration process is documented under Configuration.
- The interfaces are described in the Programmer’s reference and illustrated through samples.
Further Information