How the DNPScanner is Initialized

The device-independent scan task initialization is outlined in Device-Independent Scan Task Initialization§. The initialization is performed on startup of the scan task. The following initialization is specific to the DNPScanner:

• reads in debug device and opens file pointer to it.
  
• determines if a time sync is required; and sends the Delay Measurement function if required.
  
• determines which scan input records require setup for unsolicited messages; and sends the Enable Unsolicited Messages for those objects.

  If enable class unsol is enabled, the enable unsolicited message will be sent to the RTU using the class object instead of the objects themselves.

  
  

  The corresponding Disable Unsolicited message will be sent if the scan input record, scan input status or communication port is disabled.

  
  
• if enable class assign is enabled, the class assign message will be sent to the RTU for those objects configured in the scan input table with a valid class number.

A data link reset function is issued to the remote device under the following conditions:

• the very first message sent to the remote device, or
• after a failure to send any subsequent messages to the remote device