FieldServer FS-8700-47 instruction manual Appendix A.20. Multiple requests in a single poll

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FS-8700-47 DNP 3.0 Driver Manual

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Appendix A.20. Multiple requests in a single poll.

To provide level 2 compliance a DNP 3.0 device must support the ability to serve responses to single polls that contain requests for multiple object types. Outstations commonly use this technique to send a single message requesting class 1, 2 and 3 data. From version 1.03j onwards the driver acting as a client can send requests which contain multiple objects.

To have the driver request multiple object types in a single poll it is necessary to associate multiple Map Descriptors for this common purpose. This is done by specifying the 'dnpMultiMsg' parameter in the Map Descriptor. Assign the same positive whole number to all Map Descriptors to be associated. When the driver processes an active Map Descriptor with a non zero dnpMultiMsg parameter value it locates other Map Descriptors with he same dnpMultiMsg parameter value and uses all of these to form the poll.

When configuring the Client side Map Descriptors for this purpose, only one of the associated Map Descriptors may be set to active. The other Map Descriptors must be set as Server/Passive.

In the example below the driver finds the Map Descriptor called Class0. It sees that dnpMultiMsg is non zero and has a value of 1. It searches through the remaining Map Descriptors to find any other with dnpMultiMsg =1.and finds the Map Descriptor called Class1. Now the driver sends a single message that requests class 0 and class 1 info.

Map_Descriptors

 

 

 

 

 

 

 

 

 

 

 

Map_Descriptor_Name

,Data_Array_Name

,Data_Array_Offset

,Function

,Node_Name

,Address

,Length

,dnpDataType

,dnpDataVari

,dnpAssociate

,Scan_Interval

,dnpMultiMsg

Class0

,DA_Class0

,0

,Rdbc

,Node_A

,0

,1

,60

,1

,1

,2.0s

,1

Class1

,DA_Class1

,0

,Server

,Node_A

,0

,1

,60

,2

,1

,2.0s

,1

 

 

 

 

 

 

 

 

 

 

 

 

If the driver is configured as a Server then no action is required. Simply ensure that that there is a Server Map Descriptor for each object requested. No special actions are required to configure the Server to respond to requests for multiple object types.

FieldServer Technologies 1991 Tarob Court Milpitas, California 95035 USA Web: www.fieldserver.com Tel: (408) 262 2299 Fax: (408) 262 2269 Toll Free: (888) 509 1970 email: support@fieldserver.com

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Contents Driver Manual FS-8700-47 DNP Table of Contents FS-8700-47 DNP 3.0 Driver Manual Table of Contents DNP 3.0 Driver Description Page FS-8700-47 DNP 3.0 Driver Manual Connection Notes Hardware ConnectionsData Arrays Configuring the FieldServer as a DNP 3.0 Driver ClientClient Side Node Descriptors Client Side Connection DescriptorsDriver Specific Map Descriptor Parameters Timing Parameters Map Descriptor Example 1 Simple Read Map Descriptor Example 3 Simple Read Extract Value & Status Map Descriptor Example 4 Reading Class Data Map Descriptor Example 6 Read an unknown variation Server Side Connection Descriptors Configuring the FieldServer as a DNP 3.0 Driver ServerServer Side Node Descriptors Driver Specific Map Descriptor Parameters Map Descriptor Example 2 Class Data Map Descriptor Example 1 Discrete DataRTU Map Descriptor Example 3 Class Data another exampleMap Descriptor Example 4 Default Variation Variation zero Map Descriptor Example 5 ClassDataServingCtrl AnaInputs Map Descriptor Example 6 Unsolicited Messages Server Side Limitations Appendix A.2. DNP Driver Functionality Appendix A. Advanced Topics Appendix A.1. DNP 3.0 ProtocolAppendix A.3. DNP Objects mapped to FieldServer Data Arrays Appendix A.4. Channel Idle, Master & Slave IdleAppendix A.6. App Layer Functionality in the Master Appendix A.5. DLL Layer Functionality in the MasterIncoming Internal Indications Bytes Appendix A.7. Internal Indications, Object 80 and DnpiiPage ServerIIArray Internal Indications reported in ResponsesResponses to Polls for Object 80 Internal Indications Dnpstats Appendix A.8. DNPStatsAppendix A.9. DNP 3.0 Data Objects Counter Change Event All Variations See notes in Appendix A.10 for function code FS-8700-47 DNP 3.0 Driver Manual Appendix A.12. FieldServer DNP Node Number Appendix A.11. Controlling the DNP 3.0 Driver’s QualifierAppendix A.15. Link Reset Appendix A.13. DnpSubTypeAppendix A.14. Communication Stats Appendix A.17. dnpIndexStyle Appendix A.16. Controlling DA OffsetsDatime Appendix A.18. Real Time Clock SynchronizationPage Appendix A.19. Select and Operate Page Page Appendix A.20. Multiple requests in a single poll Appendix B. Driver Error Messages Page Page Page FYI
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