Synchronous Reply Processing

This sequence of actions takes place once a received device Command is deemed to be a reply to a previously sent server command.

First thing to be done here is finding a server command reply to those is represented by the current device Command.

To do that, driver evaluates the Reply ID Expression. This expression must return a String value representing unique ID of the reply.

Once the device reply ID is known, driver finds a server command with the same ID and:

  • if the server command was sent during a variable read process, reading process resumes and Read Result Processing Expression is evaluated to convert the Command to variable's value.
  • if the server command was sent during a variable write process, writing process resumes and Write Result Processing Expression is evaluated to figure out if device confirms successful writing.
  • if the server command was sent during a function execution process, execution process resumes and Execution Result Processing Expression is evaluated to convert the Command to function's output value.

If device communication protocol uses numeric command IDs, those IDs should be represented to Strings by Command ID Expression and Reply ID Expression.

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