In order to use unsolicited messaging on an In-Chassis DNP application, your client (DNP master) will need to be connected to via a TCP/IP connection. All DNP Ethernet devices must support both TCP/IP and UDP for their transport layers. Since TCP/IP is the only connected type of messaging, then unsolicited DNP messages will only be sent out the client that is connected using TCP/IP on the DNP Ethernet network (the DNPSNET module has only 1 TCP/IP connection, and many UDP sockets).
The following parameters are required for unsolicited messaging:
Unsolicited Response : Yes #Generate Unsolicited responses (Yes or No)
Class 1 Unsol Resp Min : 1 #1-255 min number of events before send
Class 2 Unsol Resp Min : 1 #1-255 min number of events before send
Class 3 Unsol Resp Min : 1 #1-255 min number of events before send
Unsol Resp Delay : 2000 #0-65535 mSec before events sent
UResp Master Address : 1 #DNP address of master to send UResp data
AI Events with time : Yes #timestamp AI Event data default (Yes or No)
Time Sync Before Events : Yes #timesync module before events gen (Yes or No)
By setting the Unsolicited Response to Yes the module will begin to generate unsolicited messages, but only after the master has issued a function 20 command to our DNPSNET module to authorize unsolicited messages from the slave.
The Class XX Unsol Resp Min will set the minimum number of events to report to the master. With the above examples, the DNPSNET module will send an unsolicited message when 1 event is in the event queue. If you set the parameter to a value of 10, the module will wait until 10 events have occurred for the given class before sending an unsolicited message to the master.
The Unsol Resp Delay is the minimum number of milliseconds to wait until the DNPSNET module will send out an unsolicited message to the master.
UResp Master Address sets what address to send the unsolicited message to. This must match the setting of your master station.
AI Events With Time specifies if you would like to have the analog input events time stamped. When using events you will almost always want to set this parameter to yes.
Finally, Time Sync Before Events, when set to yes, will cause the module to set the IIN bit (Internal Indication bit) to tell the master that the module needs the master to write the date and time to our module. Until the master writes the time to our module, the module will not generate an event.
If events are being generated by the module but the module isn't sending the unsolicited messages please review the requirements:
1) "Unsolicited Response" in the module must be enabled
2) The client (master) must have a TCP connection open to the module
3) The client's DNP address must match the modules "UResp Master Address" setting
4) The client must send the object 20 message authorizing the module to send unsolicited data