Indirect referencing in process control routines

• US 6,385,496 B1
• Filed: 03/12/1999
• Issued: 05/07/2002
• Est. Priority Date: 03/12/1999
• Status: Expired due to Term

• Current Assignee: Fisher-Rosemount Systems Incorporated (Emerson Electric Company)
• Original Assignee: Fisher-Rosemount Systems Incorporated (Emerson Electric Company)
• Inventors: Stevenson, Dennis L., Havekost, Robert B., Irwin, William G., Deitz, David L.
• Primary Examiner(s): Grant, William
• Assistant Examiner(s): Garland, Steven R.
• Application Number:
  US09/267,431
• Time in Patent Office: 1,152 Days
• Field of Search: 700/2, 700/9, 700/17, 700/86, 700/87, 700/89, 700/266, 717/5, 717/10, 707/103, 707/104.1, 707/100, 709/331, 709/332, 703/4, 703/6, 703/13
• US Class Current: 700/87
• CPC Class Codes: G05B 19/052 Linking several PLC's
• CPC Class Codes: G05B 19/056 Programming the PLC
• CPC Class Codes: G05B 19/4185 characterised by the network communication
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]
• CPC Class Codes: Y10S 707/99945 Object-oriented database structure processing
• CPC Class Codes: Y10S 707/99948 Application of database or data structure, e.g. distributed, multimedia, or image

Abstract

A generic process control routine for a process control system is written to include alias names and dynamic reference parameters. Before execution of a process control function on a particular unit of the process control system, an instance of the generic routine is created, in which the alias names are replaced by parameters defined in an alias resolution table for the particular unit. The controller then executes the instantiated version of the generic routine to control operation of the unit. The generic routine can have multiple algorithms associated therewith, wherein each of the algorithms is designed to control different units having somewhat different hardware, even though these different units perform essentially the same function within the process control system. The generic routine may also be used with multiple classes of hardware that perform different functions within the process control system. The dynamic reference parameters of the generic process control routine enable a field to be specified at or during run-time and include a reference attribute that stores a path or tag to the referenced field, a connection attribute that identifies whether an actual connection to the field specified by the reference attribute can be made, attributes that enable reading of and/or writing to the field specified by the reference attribute as a string or as a numerical value and attributes that enable status information of the referenced field to be accessed.

Claims

1. A process control system for use in controlling a process, comprising:

a controller;

a memory; and

a control routine used to control at least a portion of the process;

wherein the control routine is stored in the memory, the controller creates an executable version of the control routine and controls the portion of the process by executing the executable version of the control routine; and

wherein the control routine includes a dynamic reference parameter having multiple attributes including a reference attribute that holds a field value specifying a field to which the dynamic reference parameter points and that can be assigned after creation of the executable version of the control routine and wherein said field value specifies a field having multiple attributes.

2. The process control system of claim 1, wherein another of the multiple attributes is a connection attribute that provides an indication of whether the field value of the reference attribute is a valid reference.

3. A process control system for use in controlling a process, comprising:

a controller;

a memory; and

a control routine used to control at least a portion of the process;

wherein the control routine is stored in the memory, the controller creates an executable version of the control routine and controls the portion of the process by executing the executable version of the control routine;

wherein the control routine includes a dynamic reference parameter having multiple attributes including a reference attribute that holds a field value specifying a field to which the dynamic reference parameter points and that can be assigned after creation of the executable version of the control routine and wherein another of the multiple attributes is a read/write attribute that reads from or writes to the field specified by the reference attribute.

4. The process control system of claim 3, wherein the read/write attribute reads or writes as a string value.

5. The process control system of claim 3, wherein the read/write attribute reads or writes as a numerical value.

6. The process control system of claim 3, wherein the read/write attribute reads or writes as a boolean value.

7. The process control system of claim 3, wherein the read/write attribute reads or writes as an array value.

8. The process control system of claim 3, wherein a third one of the multiple attributes is a connection attribute that provides an indication of whether the field value of the reference attribute is a valid reference.

9. A process control system for use in controlling a process, comprising:

a controller;

a memory; and

a control routine used to control at least a portion of the process;

wherein the control routine is stored in the memory, the controller creates an executable version of the control routine and controls the portion of the process by executing the executable version of the control routine;

wherein the control routine includes a dynamic reference parameter having multiple attributes including a reference attribute that holds a field value specifying a field to which the dynamic reference parameter points and that can be assigned after creation of the executable version of the control routine and wherein another of the multiple attributes is a status attribute that reads a status associated with the field specified by the reference attribute.

10. The process control system of claim 9, wherein the status attribute reads a write status, indicating a success or a failure of a previous write to the field specified by the reference attribute.

11. The process control system of claim 9, wherein a third one of the multiple attributes is a connection attribute that provides an indication of whether the field value of the reference attribute is a valid reference.

12. A process control system for use in controlling a process, comprising:

a controller;

a memory; and

a control routine used to control at least a portion of the process;

wherein the control routine is stored in the memory, the controller creates an executable version of the control routine and controls the portion of the process by executing the executable version of the control routine;

wherein the control routine includes a dynamic reference parameter having multiple attributes including a reference attribute that holds a field value specifying a field to which the dynamic reference parameter points and that can be assigned after creation of the executable version of the control routine and wherein a second one of the multiple attributes is a connection attribute that provides an indication of whether the field value of the reference attribute is a valid field and a third one of the multiple attributes is a read/write attribute that reads from or writes to the field specified by the reference attribute.

13. The process control system of claim 12, wherein a fourth one of the multiple attributes is a status attribute that reads a status associated with the field specified by the reference attribute.

14. The process control system of claim 12, wherein a third one of the multiple attributes is a connection attribute that provides an indication of whether the field value of the reference attribute is a valid reference.

15. A software control component for use in a process control system which has a controller that controls a process, the software control component comprising:

a computer-readable memory; and

a control routine stored on the computer-readable memory and adapted to be used by the controller to control at least a portion of the process;

wherein the control routine includes a dynamic reference parameter having multiple attributes including a reference attribute that holds a field value specifying a field to which the dynamic reference parameter points and that can be assigned after creation of the executable version of the control routine and wherein said field value specifies a field having multiple attributes.

16. The software control component of claim 15, wherein another of the multiple attributes is a connection attribute that provides an indication of whether the field value of the reference attribute is a valid field.

17. A software control component for use in a process control system which has a controller that controls a process, the software control component comprising:

a computer-readable memory; and

a control routine stored on the computer-readable memory and adapted to be used by the controller to control at least a portion of the process;

wherein the control routine includes a dynamic reference parameter having multiple attributes including a reference attribute that holds a field value specifying a field to which the dynamic reference parameter points and that can be assigned after creation of the executable version of the control routine and wherein another of the multiple attributes is a read/write attribute that reads from or writes to the field specified by the reference attribute.

18. The software control component of claim 17, wherein the read/write attribute reads or writes as a string value.

19. The software control component of claim 17, wherein the read/write attribute reads or writes as a numerical value.

20. The software control component of claim 17, wherein the read/write attribute reads or writes as a boolean value.

21. The software control component of claim 17, wherein the read/write attribute reads or writes as an array value.

22. The software control component of claim 17, wherein another of the multiple attributes is a connection attribute that provides an indication of whether the field value of the reference attribute is a valid field.

23. A software control component for use in a process control system which has a controller that controls a process, the software control component comprising:

a computer-readable memory; and

a control routine stored on the computer-readable memory and adapted to be used by the controller to control at least a portion of the process;

wherein the control routine includes a dynamic reference parameter having multiple attributes including a reference attribute that holds a field value specifying a field to which the dynamic reference parameter points and that can be assigned after creation of the executable version of the control routine and wherein another of the multiple attributes is a status attribute that reads a status associated with the field specified by the reference attribute.

24. The software control component of claim 23, wherein the status attribute reads a write status, indicating a success or a failure of a previous write to the field specified by the reference attribute.

25. The software control component of claim 23, wherein another of the multiple attributes is a connection attribute that provides an indication of whether the field value of the reference attribute is a valid field.

26. A software control component for use in a process control system which has a controller that controls a process, the software control component comprising:

a computer-readable memory; and

a control routine stored on the computer-readable memory and adapted to be used by the controller to control at least a portion of the process;

wherein the control routine includes a dynamic reference parameter having multiple attributes including a reference attribute that holds a field value specifying a field to which the dynamic reference parameter points and that can be assigned after creation of the executable version of the control routine and wherein a second one of the multiple attributes is a connection attribute that provides an indication of whether the field value of the reference attribute is a valid field and a third one of the multiple attributes is a read/write attribute that reads from or writes to the field specified by the reference attribute.

27. The software control component of claim 26, wherein a fourth one of the multiple attributes is a status attribute that reads a status associated with the field specified by the reference attribute.

28. The software control component of claim 26, wherein another of the multiple attributes is a connection attribute that provides an indication of whether the field value of the reference attribute is a valid field.