I/O task
This section describes how to configure the namespace of the TwinCAT OPC UA Server in order to gain access to the symbols of a task with process image. This requires the following steps to be carried out:
- Activating the symbolism
- Configuration of the server
Activating the symbolism
You can provide the variables of a task with a process image via OPC UA. To do this, you must enable the "Create symbols" option in the task settings. This generates symbols and makes them available via the online symbolism. In the same dialog, you will also find the ADS port, which will be required later in the configuration process.
Configuration of the server
You can now use the TwinCAT OPC UA Configurator to configure the TwinCAT OPC UA Server so that it accesses the online symbolism of the task and makes them available in its address space.
Add a new device in the Data Access tab of the TwinCAT OPC UA Configurator. Select the AMS Net ID of your device and enter the ADS port of the task (see above).
In the selection list of the "Type" field, select the "TwinCAT Symbol Server" entry.
After activating the TwinCAT project, the symbols are ready and the TwinCAT OPC UA Server can read them and build up its address space accordingly.