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The line category determines basically the type of interface to a particular device. The list of available communication protocols in the configuration of stations, which are the line children, varies according to the chosen line category. Most of the lines require the configuration of specific parameters depending on the configured line category. A typical example is an asynchronous communication line and settings of transmission parameters for individual line modes. A detailed description of these parameters and their interpretation you can find in topic communication protocols.
Note: Changing the line category is not supported by the D2000 KOM process and requires a restart of this process. The recommended alternative (which does not require a restart) is to create a new line (with the correct category), new station(s), and migrate the I/O tags using XML export/import,
RQ delay
This time represents the delay [ms], that is inserted between an incoming request for communication and its processing via the thread of the communication line. The parameter may be used to slow down (delay) communication or simulation.
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