System and methodology providing optimized data exchange with industrial controller

• US 7,725,528 B1
• Filed: 03/06/2002
• Issued: 05/25/2010
• Est. Priority Date: 03/06/2002
• Status: Active Grant

• Current Assignee: Rockwell Software Incorporated (Rockwell Automation, Inc.)
• Original Assignee: Rockwell Automation Technologies Incorporated (Allen-Bradley Co., Inc.)
• Inventors: Grissom, Carmen D. Jr., Zink, Steven M., Baier, John Joseph, Johnston, David A.
• Primary Examiner(s): Nguyen; Thu
• Assistant Examiner(s): TRUONG, LAN DAI T
• Application Number:
  US10/092,323
• Time in Patent Office: 3,002 Days
• Field of Search: 709/223, 709/225, 709/203, 709/208, 709/217, 709/230
• US Class Current: 709/203
• CPC Class Codes: G05B 19/054 Input/output

Abstract

The present invention relates to a system and methodology facilitating network communications between an industrial control system and a client application that interacts with a plurality of data items on the control system. The client application initiates a request or query to the industrial control system for an identification of selected data items of interest. Based on information received in the request, an aggregation component can be constructed by the client, wherein names and buffer allocations relating to the data items of interest are provided. The aggregation component is then installed by the client and updated in the industrial control system, thus providing information access to the client application when fresh or updated information is desired. Information is accessed via a communications packet that is generated from the data items identified in the aggregation component. Information transmitted to the control system can also be optimized by identifying the information via handle identifiers that are employed in place of explicit reference or tag names.

Claims

1. An industrial control system, comprising:

a processor;

a computer readable storage medium operationally coupled to the processor and storing computer executable instructions, the computer executable instructions, when executed by the processor, implement components comprising;

a primary aggregation component associated with an industrial controller, the primary aggregation component is created, via the processor, and defined in response to a query received from an entity remote to the industrial controller and is installed on the industrial controller, the primary aggregation component aggregates a plurality of selected data items stored in the industrial controller into an aggregated subset of data items;

a communications component associated with the remote entity, the communications component reads the aggregated subset of data items via a singular communications packet across a network, the communications component causes addition of at least one secondary aggregation component at the industrial controller in response to increased data demands, wherein the communication component causes removal of the at least one secondary aggregation components in response to decreased data demands; and

an update component associated with the remote entity, the update component receives handle information from the industrial controller across the network relating to the plurality of selected data items, the update component employs the handle information to generate an update data packet request that is transmitted across the network to the industrial controller to update one or more data items of the aggregated subset of data items in the industrial controller, wherein the handle information provides a fixed length reference pointer to a memory address in the industrial controller for each of variable length tag references of the plurality of selected data items, wherein the update data packet request employs the fixed length reference pointer in place of a variable length tag reference for each of the one or more data items of the aggregated subset of data items that are to be updated.

2. The system of claim 1, the entity is a client application that selects and requests the subset of data items from the controller.

3. The system of claim 2, the client application is at least one of a data logging application and a Human and Machine Interface (HMI) that interacts with the industrial controller.

4. The system of claim 2, further comprising a communications server adapted to interact with the client application, the network and the industrial controller, the industrial controller including a communications driver to interface with the communications server and the network.

5. The system of claim 1, the communications component sends a data request to the industrial controller relating to the aggregated subset of data items.

6. The system of claim 5, the industrial controller sending a response to the request including at least one of tag and value information associated with the tag, the tag and value information relating to the aggregated subset of data items.

7. The system of claim 6, the communications component employing the tag and value information received in the response to build the primary aggregation component on the industrial controller.

8. The system of claim 1, further comprising at least one of dynamically increasing and decreasing the amount of selected data items in the primary aggregation component based upon data demands received from the network.

9. The system of claim 1, the primary aggregation component is an object including at least one of class attributes, instance attributes, services and a data buffer.

10. The system of claim 9, the class attributes supply information such as revision level information of the object, an instance number, and a number of instances of an associated class.

11. The system of claim 9, the instance attributes include setting for at least one of object update times, event triggers, whether to update the object based on rate, demand and other criteria, where in a data stream triggers are located, whether to continue on an overflow, number of drivers currently installed, timestamp information, size of buffers, start times, or object lifetime settings.

12. The system of claim 9, the services include at least one of Get All Attributes, Get All List, Set Attributes List, Reset, Start, Stop, Create Object or Delete Object.

13. The system of claim 9, the data buffer including at least one of 1 to L data items, L being an integer greater than 1, and includes at least one of the following types:

single valued elements, bit, byte, 16 bit, 32 bit, greater than 32 bit configurations, unsigned integers, signed integers, floating point elements, single dimension array, multiple dimension array configurations, or user defined tags (UDT).

14. The system of claim 13, the single valued elements include at least one of a tag identifier or an associated value.

15. The system of claim 13, the single dimension arrays include at least one of an array element ID, a value, a begin array element ID or a length.

16. The system of claim 1, further comprising removing the primary aggregation component based upon at least one of a loss of communications and a connection timeout.

17. The system of claim 1, further comprising removing the primary aggregation component based upon an explicit command.

18. A method to facilitate data communications with an industrial controller, comprising:

employing a processor executing computer executable instructions stored on a computer readable storage medium to implement the following acts;

requesting tag information from an industrial controller across an industrial control network for a plurality of selected data items in the controller;

building an aggregation object from the tag information provided by the industrial controller;

installing the aggregation object on the industrial controller;

installing at least one secondary aggregation component on the industrial controller upon increased data demands;

wherein the installing caused by a communication component associated with a remote entity;

removing the at least one secondary aggregation components upon decreased data demands;

wherein the removing caused by the communication component associated with the remote entity;

updating the aggregation object data on the industrial controller;

receiving by the communication component associated with the remote entity data from the aggregation object that has been updated by the industrial controller via a singular communication packet;

receiving by an update component associated with the remote entity handle information from the industrial controller relating to the plurality of selected data items, wherein the handle information provides a fixed length reference pointer to a memory address in the industrial controller for each of variable length tag references of the plurality of selected data items; and

employing by the update component associate with the remote entity only the handle information to generate an update data packet that is transmitted across the network to the industrial controller to update the plurality of selected data items in the industrial controller, wherein the update data packet employs the fixed length pointer in place of a variable length tag reference for each of the plurality of selected data items that are to be updated.

19. The method of claim 18, further comprising updating the object via at least one of a periodic occurrence, an event driven occurrence, and a request.

20. The method of claim 18, further comprising removing the object from the controller when a client no longer requests data items of interest.

21. The method of claim 20, further comprising removing the object based upon at least one of an event and network connections being disrupted for a time period that is greater than a predetermined amount of time that is configured at the controller.

22. The method of claim 18, further comprising placing data items of interest in a scanning list.

23. The method of claim 22, the list indicates which data items are to be periodically updated for a client application.

24. A system to facilitate data communications with an industrial controller, comprising:

a processor;

a computer readable storage medium storing computer executable instructions, the computer executable instructions, when executed by the processor, implement components comprising;

means for requesting, by the processor, tag identifiers from a industrial controller across a communications network, wherein the tag identifiers are associated with a plurality of selected data items in the industrial controller;

means for constructing an aggregation object from the tag identifiers requested from the industrial controller;

means for installing the aggregation object on the industrial controller, wherein the means for installing installs at least one secondary aggregation component on the controller upon increased data demands and removes the at least one secondary aggregation components upon decreased data demands, wherein the installing and removing are caused by a communication component associated with a remote entity;

means for refreshing by the industrial controller the aggregation object on the industrial controller;

means for transmitting by the industrial controller by data across the communications network from the optimized data packet that has been refreshed by the industrial controller; and

means for updating the industrial controller via employment of handle information by an update component associated with a remote entity to generate an update data packet that is transmitted across the network to the industrial controller to update the plurality of selected data items in the industrial controller, wherein the handle information provides a fixed length reference pointer to a memory address in the industrial controller for each of variable length tag references for each of the plurality of selected data items that are to be updated, wherein the update data packet employs the fixed length reference pointer in place of the tag identifier as variable length tag reference for each of the plurality of selected data items that are to be updated.

25. An industrial controller, comprising:

a processor;

a computer readable storage medium storing computer executable instructions, the computer executable instructions, when executed by the processor, implement components comprising;

a first component that processes information received from a remote entity across a network;

a primary aggregation component that aggregates a plurality of selected data items into an aggregated subset of data items, the primary aggregation component defined and installed at the industrial controller by an entity remote from the industrial controller;

a communications component associated with the entity remote from the controller, the communications component reads the subset of data items via a singular communications packet across the network, the communications component causes addition of at least one secondary aggregation component at the industrial controller upon increased data demands, wherein the communication component causes removal of the at least one secondary aggregation components upon decreased data demands; and

a update component associated with the entity remote from the industrial controller, the update component receives handle information from the industrial controller relating to the selected data items and employs the handle information to generate an update data packet request that is transmitted across the network to the industrial controller to update the plurality of data items of the aggregated subset of data items in the industrial controller, wherein the handle information provides a fixed length reference pointer to a memory address in the controller in place of a variable length tag reference for each of the plurality of selected data items that are to be updated, wherein the update data packet employs the fixed length reference pointer in place of a variable length tag reference for the plurality of selected data items of the aggregated subset of data items that are to be updated.

26. The controller of claim 25, the first component is a processor adapted to provide access to a variable memory associated with the controller, the variable memory storing the one or more selected data items.

27. The controller of claim 26, the processor interacts with the communications component to aggregate and transmit the subset of data items, the communications component is a communications driver configured for the network.

28. The controller of claim 27, the network is at least one of an Ethernet, ControlNet, a DeviceNet, RS-232, RS-422, or RS-485.

29. The controller of claim 27, the communications driver adapted to communicate with a communications server associated with a client application.

30. The controller of claim 29, the client application is a Human and Machine Interface (HMI).

31. The controller of claim 29, the communications server installs the aggregation component on the industrial controller.