System and method for performing interface independent virtual instrumentation functions in a graphical data flow program

• US 5,784,275 A
• Filed: 09/23/1996
• Issued: 07/21/1998
• Est. Priority Date: 09/23/1996
• Status: Expired due to Term

• Current Assignee: National Instruments Corporation (Emerson Electric Company)
• Original Assignee: National Instruments Corporation (Emerson Electric Company)
• Inventors: Sojoodi, Omid, Rust, Scott A.
• Primary Examiner(s): Elmore, Reba I.
• Assistant Examiner(s): PATEL, RAMESH B
• Application Number:
  US08/716,725
• Time in Patent Office: 666 Days
• Field of Search: 364/189, 364/191, 364/200, 364/275, 364/579, 364/580, 364/325, 364/148, 364/146, 364/187, 364/188, 395/575, 395/700, 395/425, 395/725, 395/800, 395/500, 395/275, 395/735, 395/651, 395/650, 395/733, 395/739
• US Class Current: 700/86
• CPC Class Codes: G05B 19/0426 Programming the control sequence
• CPC Class Codes: G05B 2219/23258 GUI graphical user interface, icon, function bloc editor, labview
• CPC Class Codes: G05B 2219/24081 Detect valid sequence of commands
• CPC Class Codes: G05B 2219/2656 Instrumentation

Abstract

A system and method for creating a program for controlling an instrument independent of the interface type of the instrument, in a graphical programming environment. The system comprises a computer system including a display screen and input device, an instrument coupled to the computer system, and a graphical programming environment for creating and executing programs to control the instrument. The programming environment comprises a VISA session control, VISA function nodes and VISA attribute nodes, an object manager and block diagram and front panel editors used to create a VISA virtual instrument. The method for controlling the instrument comprises displaying on the screen VISA session icons, VISA function nodes, and VISA attributes nodes and wiring them together to create the VISA virtual instrument. Virtual instruments, or graphical programs, may be created which are portable across different possible VISA I/O interface types, such as GPIB, VXI, and asynchronous serial interfaces, for coupling the instrument to the computer system. The object manager parses a class definition file to determine possible VISA classes associated with the instrument and the attributes and functions which are valid for a each class. The environment performs type propagation checking to insure that program elements are not wired together in an invalid manner by the user in order to avoid program errors. In particular, the environment checks to see that attributes to be set on and functions to be performed with the instrument are valid for the class of the VISA session associated with the instrument. The environment further performs class propagation between objects in the program to avoid programming errors.

Claims

1. A method for creating a program for controlling at least one instrument coupled to a computer system, wherein the computer system includes memory, a data processor, user input means, and a video screen, wherein the instrument couples to the computer system through one or more of a plurality of possible input/output (I/O) interface types, the method comprising:

storing in the memory a plurality of VISA resources, wherein said VISA resources are operable to control capabilities of the instrument which are independent of one or more of said plurality of possible I/O interface types for coupling said instrument to said computer system;

displaying on the screen a palette comprising VISA node icons, wherein the VISA node icons correspond to respective ones of the plurality of VISA resources;

displaying on the screen a graphical program, the graphical program including a plurality of VISA node icons from said palette comprising VISA node icons, wherein said displaying said graphical program is in response to user input, wherein said graphical program is operable to control the instrument independent of two or more of said plurality of possible input/output (I/O) interface types for coupling said instrument to said computer system.

2. The method of claim 1, wherein said graphical program is operable to control the instrument independent of two or more of said plurality of possible input/output (I/O) interface types for coupling said instrument to said computer system without any modifications to said graphical program.

3. The method of claim 1, wherein said VISA node icons comprised in said palette can be used to create a graphical program operable to control the instrument independent of said plurality of possible input/output (I/O) interface types for coupling said instrument to said computer system.

4. The method of claim 1, wherein said plurality of possible input/output (I/O) interface types for coupling said instrument to said computer system include one or more from the group comprising:

VXI message based, VXI register based, GPIB, serial, Ethernet, and wireless.

5. The method of claim 1, wherein said two or more of said plurality of possible input/output (I/O) interface types for coupling said instrument to said computer system comprises a subset of all of the possible input/output (I/O) interface types for coupling said instrument to said computer system.

6. The method as recited in claim 1, wherein said plurality of VISA node icons comprise a first plurality of nodes which are independent of I/O interface type and a second plurality of nodes which are specific to one or more, but not all, of said I/O interface types.

7. The method as recited in claim 1, wherein each of said plurality of VISA node icons references one of said plurality of VISA resources.

8. The method of claim 1, wherein said displaying on the screen said graphical program comprises displaying one or more of said VISA node icons from said palette comprising VISA node icons in a graphical program window in response to user input;

wherein said displaying on the screen said graphical program further comprises connecting said VISA node icons displayed in said graphical program window in response to user input.

9. The method as recited in claim 8, wherein said graphical program is a graphical data flow program, the method further comprising:

wherein said displaying on the screen said graphical program further comprises displaying on the screen in the graphical program one or more wires connecting said plurality of VISA node icons, wherein said one or more wires represent data flow between said corresponding plurality of VISA node icons.

10. The method as recited in claim 1, wherein said VISA node icons comprise VISA function node icons and VISA attribute node icons, wherein said VISA function node icons operate to perform functions of said plurality of VISA resources and said VISA attribute node icons operate to set and get attributes of said plurality of VISA resources.

11. The method as recited in claim 1, wherein said displaying on the screen said graphical program includes displaying on the screen a panel including one or more controls and indicators for providing input values to and receiving output values from, respectively, said plurality of VISA nodes, wherein said displaying said panel is in response to user input.

12. The method as recited in claim 11, wherein said one or more controls comprise one or more VISA session controls.

13. The method as recited in claim 1, wherein said displaying on the screen said graphical program includes:

displaying on the screen a VISA session control terminal icon representing a VISA session with said at least one instrument;

selecting a class for said VISA session in response to user input.

14. The method as recited in claim 1, wherein said displaying on the screen said graphical program includes:

displaying on the screen a VISA session control terminal icon representing a VISA session with said at least one instrument;

displaying on the screen a VISA open node icon which represents performance of a VISA open operation.

15. The method as recited in claim 1, further comprising:

constructing execution instructions in the computer system for controlling said instrument, wherein said constructing execution instructions is performed in response to said graphical program, wherein said execution instructions reference one or more of said VISA resources; and

executing said execution instructions on said computer system to control said instrument, wherein said executing includes executing said one or more of said VISA resources.

16. The method as recited in claim 1,

wherein said plurality of VISA node icons comprised in said graphical program includes a first one or more VISA node icons specific to a first subset of I/O interface types;

wherein said graphical program, without replacing any of said VISA node icons, is operable to control the at least one instrument coupled to said computer system according to a first interface type, wherein said first interface type is one of said first subset of I/O interface types;

wherein said graphical program, without replacing any of said VISA node icons, is operable to control the at least one instrument coupled to said computer system according to a second interface type, wherein said second interface type is one of said first subset of I/O interface types;

wherein said first and second interface types are different.

17. The method as recited in claim 1,

wherein said plurality of VISA node icons comprised in said graphical program includes a first one or more VISA node icons specific to a first subset of I/O interface types, wherein said graphical program is operable to control the at least one instrument coupled to said computer system according to a first interface type, wherein said first interface type is one of said first subset of I/O interface types;

the method further comprising;

modifying the graphical program to replace said first one or more VISA node icons specific to said first subset of I/O interface types with a second one or more VISA node icons specific to a second subset of I/O interface types, wherein said first subset of I/O interface types is different than said second subset of I/O interface types;

wherein said graphical program, after said modifying, is operable to control the at least one instrument coupled to said computer system according to a second interface type, wherein said second interface type is one of said second subset of I/O interface types, and wherein said second interface type is not included in said first subset of I/O interface types.

18. The method as recited in claim 1, wherein said at least one instrument comprises at least one virtual instrument.

19. An instrumentation control system, comprising:

a computer system including memory, a data processor, a user input device, and a video screen;

at least one instrument coupled to said computer system, wherein the instrument couples to the computer system through one or more of a plurality of possible input/output (I/O) interface types;

wherein the memory in the computer system stores code and data for creating a graphical program for controlling the instrument coupled to said computer system, wherein the memory in the computer system further stores a plurality of VISA resources for controlling the instrument coupled to said computer system;

wherein the data processor is operable to execute code and data from the memory in the computer system to display on the screen a graphical program, the graphical program including a plurality of VISA node icons corresponding to respective ones of the plurality of VISA resources, wherein the data processor displays said graphical program in response to user input received from said user input device, wherein said graphical program is operable to control the instrument independent of two or more of said plurality of possible input/output (I/O) interface types for coupling said instrument to said computer system.

20. The instrumentation control system of claim 19, wherein said graphical program is operable to control the instrument independent of two or more of said plurality of possible input/output (I/O) interface types for coupling said instrument to said computer system without any modifications to said graphical program.

21. The instrumentation control system of claim 19, wherein the data processor is operable to execute code and data from the memory in the computer system to display on the screen a palette comprising VISA node icons, wherein the VISA node icons correspond to respective ones of the plurality of VISA resources;

wherein the graphical program includes a plurality of VISA node icons from said palette comprising VISA node icons;

wherein said VISA node icons comprised in said palette can be used to create a graphical program operable to control the instrument independent of said plurality of possible input/output (I/O) interface types for coupling said instrument to said computer system.

22. The instrumentation control system of claim 19, wherein said plurality of possible input/output (I/O) interface types for coupling said instrument to said computer system include one or more from the group comprising:

VXI message based, VXI register based, GPIB, serial, Ethernet, and wireless.

23. The instrumentation control system of claim 19, wherein said two or more of said plurality of possible input/output (I/O) interface types for coupling said instrument to said computer system comprises a subset of all of the possible input/output (I/O) interface types for coupling said instrument to said computer system.

24. The instrumentation control system of claim 19, wherein said plurality of VISA node icons comprise a first plurality of nodes which are independent of I/O interface type and a second plurality of nodes which are specific to one or more, but not all, of said I/O interface types.

25. The instrumentation control system of claim 19, wherein each of said plurality of VISA node icons references one of said plurality of VISA resources stored in the memory of the computer system.

26. The instrumentation control system of claim 19, wherein the data processor is operable to execute code and data from the memory in the computer system to display said VISA node icons in a graphical program window in response to user input;

wherein the data processor is further operable to execute code and data from the memory in the computer system to connect said VISA node icons displayed in said graphical program window in response to user input.

27. The instrumentation control system as recited in claim 26, wherein said graphical program is a graphical data flow program;

wherein the data processor is operable to execute code and data from the memory in the computer system to display one or more wires in the graphical data flow program connecting said plurality of VISA node icons, wherein said one or more wires represent data flow between said corresponding plurality of VISA node icons.

28. The instrumentation control system as recited in claim 19, wherein said VISA node icons comprise VISA function node icons and VISA attribute node icons, wherein said VISA function node icons reference code and data which are operable to perform functions of said plurality of VISA resources and said VISA attribute node icons reference code and data which are operable to set and get attributes of said plurality of VISA resources.

29. The instrumentation control system as recited in claim 19, wherein the data processor is operable to execute code and data from the memory in the computer system to display on the screen a panel including one or more controls and indicators for providing input values to and receiving output values from, respectively, said plurality of VISA nodes, wherein the data processor displays said panel in response to user input from said user input device.

30. The instrumentation control system as recited in claim 29, wherein said one or more controls comprise one or more VISA session controls.

31. The instrumentation control system as recited in claim 19, wherein the data processor is operable to execute code and data from the memory in the computer system to display on the screen a VISA session control terminal icon in the graphical program representing a VISA session with said at least one instrument;

wherein the data processor is operable to execute code and data from the memory in the computer system to select a class for said VISA session in response to user input from said user input device.

32. The instrumentation control system as recited in claim 19, wherein the data processor is operable to execute code and data from the memory in the computer system to display on the screen a VISA session control terminal icon in the graphical program representing a VISA session with said at least one instrument;

wherein the data processor is operable to execute code and data from the memory in the computer system to display on the screen a VISA open node icon in the graphical program which represents performance of a VISA open operation.

33. The instrumentation control system as recited in claim 19,

wherein the data processor is operable to construct execution instructions in the computer system for controlling said instrument, wherein the data processor constructs said execution instructions in response to said graphical program, wherein said execution instructions reference one or more of said VISA resources;

and

wherein the data processor is operable to execute said execution instructions to control said instrument, wherein said execution includes executing said one or more of said VISA resources.

34. The instrumentation control system as recited in claim 19,

wherein said plurality of VISA node icons comprised in said graphical program includes a first one or more VISA node icons specific to a first subset of I/O interface types;

wherein said graphical program, without replacing any of said VISA node icons, is operable to control the at least one instrument coupled to said computer system according to a first interface type, wherein said first interface type is one of said first subset of I/O interface types;

wherein said graphical program, without replacing any of said VISA node icons, is operable to control the at least one instrument coupled to said computer system according to a second interface type, wherein said second interface type is one of said first subset of I/O interface types;

wherein said first and second interface types are different.

35. The instrumentation control system as recited in claim 19,

wherein said plurality of VISA node icons comprised in said graphical program includes a first one or more VISA node icons specific to a first subset of I/O interface types, wherein said graphical program is operable to control the at least one instrument coupled to said computer system according to a first interface type, wherein said first interface type is one of said first subset of I/O interface types;

wherein the data processor is operable to modify the graphical program to replace said first one or more VISA node icons specific to said first subset of I/O interface types with a second one or more VISA node icons specific to a second subset of I/O interface types, wherein said first subset of I/O interface types is different than said second subset of I/O interface types;

wherein said graphical program, after said modifying, is operable to control the at least one instrument coupled to said computer system according to a second interface type, wherein said second interface type is one of said second subset of I/O interface types, and wherein said second interface type is not included in said first subset of I/O interface types.

36. The instrumentation control system as recited in claim 19, wherein said at least one instrument comprises at least one virtual instrument.

37. A computer-readable storage media for operating in a computer system, the computer system including a display screen, an input device, memory, and a data processor operably coupled to an instrument, wherein the storage media includes a substrate having a physical configuration representing data, the storage media comprising:

instructions for storing in the memory a plurality of VISA resources, wherein said VISA resources are operable to control capabilities of the instrument which are independent of one or more of said plurality of possible I/O interface types for coupling said instrument to said computer system;

instructions for displaying on the screen a palette comprising VISA node icons, wherein the VISA node icons correspond to respective ones of the plurality of VISA resources;

instructions for displaying on the screen a graphical program, the graphical program including a plurality of VISA node icons from said palette comprising VISA node icons, wherein said instructions for displaying said graphical program execute in response to user input, wherein said graphical program is operable to control the instrument independent of two or more of said plurality of possible input/output (I/O) interface types for coupling said instrument to said computer system.

38. The media of claim 37, wherein said graphical program is operable to control the instrument independent of two or more of said plurality of possible input/output (I/O) interface types for coupling said instrument to said computer system without any modifications to said graphical program.

39. The media of claim 37, wherein said VISA node icons comprised in said palette can be used to create a graphical program operable to control the instrument independent of said plurality of possible input/output (I/O) interface types for coupling said instrument to said computer system.

40. The media of claim 37, wherein said plurality of possible input/output (I/O) interface types for coupling said instrument to said computer system include one or more from the group comprising:

VXI message based, VXI register based, GPIB, serial, Ethernet, and wireless.

41. The media of claim 37, wherein said two or more of said plurality of possible input/output (I/O) interface types for coupling said instrument to said computer system comprises a subset of all of the possible input/output (I/O) interface types for coupling said instrument to said computer system.

42. The media as recited in claim 37, wherein said plurality of VISA node icons comprise a first plurality of nodes which are independent of I/O interface type and a second plurality of nodes which are specific to one or more, but not all, of said I/O interface types.

43. The media as recited in claim 37, wherein each of said plurality of VISA node icons references one of said plurality of VISA resources.

44. The media of claim 37, wherein said instructions for displaying on the screen said graphical program comprises instructions for displaying one or more of said VISA node icons from said palette comprising VISA node icons in a graphical program window in response to user input;

wherein said instructions for displaying on the screen said graphical program further comprises instructions for connecting said VISA node icons displayed in said graphical program window in response to user input.

45. The media as recited in claim 44, wherein said graphical program is a graphical data flow program, the media further comprising:

wherein said instructions for displaying on the screen said graphical program further comprise instructions for displaying on the screen in the graphical program one or more wires connecting said plurality of VISA node icons, wherein said one or more wires represent data flow between said corresponding plurality of VISA node icons.

46. The media as recited in claim 37, wherein said VISA node icons comprise VISA function node icons and VISA attribute node icons, wherein said VISA function node icons operate to perform functions of said plurality of VISA resources and said VISA attribute node icons operate to set and get attributes of said plurality of VISA resources.

47. The media as recited in claim 37, wherein said instructions for displaying on the screen said graphical program include instructions for displaying on the screen a panel including one or more controls and indicators for providing input values to and receiving output values from, respectively, said plurality of VISA nodes, wherein said displaying said panel is in response to user input.

48. The media as recited in claim 47, wherein said one or more controls comprise one or more VISA session controls.

49. The media as recited in claim 37, wherein said instructions for displaying on the screen said graphical program include:

instructions for displaying on the screen a VISA session control terminal icon representing a VISA session with said at least one instrument;

instructions for selecting a class for said VISA session in response to user input.

50. The media as recited in claim 37, wherein said instructions for displaying on the screen said graphical program includes:

instructions for displaying on the screen a VISA session control terminal icon representing a VISA session with said at least one instrument;

instructions for displaying on the screen a VISA open node icon which represents performance of a VISA open operation.

51. The media as recited in claim 37, further comprising:

instructions for constructing execution instructions in the computer system for controlling said instrument, wherein said constructing execution instructions is performed in response to said graphical program, wherein said execution instructions reference one or more of said VISA resources; and

instructions for executing said execution instructions on said computer system to control said instrument, wherein said executing includes executing said one or more of said VISA resources.

52. The media as recited in claim 37,

wherein said plurality of VISA node icons comprised in said graphical program includes a first one or more VISA node icons specific to a first subset of I/O interface types;

wherein said graphical program, without replacing any of said VISA node icons, is operable to control the at least one instrument coupled to said computer system according to a first interface type, wherein said first interface type is one of said first subset of I/O interface types;

wherein said graphical program, without replacing any of said VISA node icons, is operable to control the at least one instrument coupled to said computer system according to a second interface type, wherein said second interface type is one of said first subset of I/O interface types;

wherein said first and second interface types are different.

53. The media as recited in claim 37,

wherein said plurality of VISA node icons comprised in said graphical program includes a first one or more VISA node icons specific to a first subset of I/O interface types, wherein said graphical program is operable to control the at least one instrument coupled to said computer system according to a first interface type, wherein said first interface type is one of said first subset of I/O interface types;

the media further comprising;

instructions for modifying the graphical program to replace said first one or more VISA node icons specific to said first subset of I/O interface types with a second one or more VISA node icons specific to a second subset of I/O interface types, wherein said first subset of I/O interface types is different than said second subset of I/O interface types;

wherein said graphical program, after said modifying, is operable to control the at least one instrument coupled to said computer system according to a second interface type, wherein said second interface type is one of said second subset of I/O interface types, and wherein said second interface type is not included in said first subset of I/O interface types.

54. The media as recited in claim 37, wherein said at least one instrument comprises at least one virtual instrument.