System and method for performing processing in a testing system
A system and method is provided for performing processing in a test system. A flexible platform may be provided for developing test programs for performing automated testing. In one such platform, the tester and its instruments are isolated from the tester operating system, permitting any tester operating system to be used. In another example implementation, a user layer of the platform is isolated from the physical layer of the architecture, permitting hardware-independent test programs that can be created and used among different testers having different test hardware and software. In yet another implementation, execution of a test program is isolated from a tester platform operating system, permitting the test program to function independent from the tester platform. In another embodiment, functionality is implemented on the platform such that functions are only added, and that existing links to functions are not broken, ensuring continued test system operation when new software, hardware and/or features are added to the platform. The test system may include a non-deterministic computer system. In one example test system, the system forces execution of one or more computer instructions performed by the non-deterministic computer system to execute within a constant execution time. A deterministic engine, if necessary, waits a variable amount of time to ensure that the execution of the computer instructions is performed over the constant execution time. Because the execution time is constant, the execution is deterministic and therefore may be used in applications requiring deterministic behavior. For example, such a deterministic engine may be used in automated test equipment (ATE) applications.
1 . A system for performing a testing process, the system comprising:
one or more test instruments, each having respective one or more driver programs and wherein at least one of the driver programs includes one or more functions;
a test program that, when executed, performs a procedure on the one or more test instruments, the test program accessing the one or more test instruments through the one or more driver programs; and
a memory structure, wherein the one or more functions of the at least one of the driver programs are contained within a fixed location with the memory structure.
2 . The system according to claim 1 , wherein the memory structure is included in a memory of a computer system, and wherein the one or more functions are loaded in the memory of the computer system.
3 . The system according to claim 1 , wherein a change in the at least one of the driver programs does not produce a corresponding change in the memory structure.
4 . The system according to claim 3 , wherein the one or more functions are located in a first location in the memory structure.
5 . The system according to claim 4 , wherein the change in the at least one of the driver programs includes adding one or more additional functions.
6 . The system according to claim 4 , wherein the change in the at least one of the driver programs includes modifying at least one of the one or more functions.
7 . The system according to claim 4 , wherein the one or more additional functions are added in a second location following the first location in the memory structure.
8 . The system according to claim 7 , wherein the addition of the one or more additional functions does not change the location of the one or more functions in the first location in the memory structure.
9 . The system according to claim 8 , wherein the memory structure further comprises a vtable.
10 . The system according to claim 9 , wherein the addition of the one or more additional functions does not change a location of the one or more functions in the vtable.
11 . The system according to claim 6 , wherein the change in the virtual instrument entity includes adding at least one modified function.
12 . The system according to claim 11 , wherein a change in a platform entity includes adding at least one modified function.
13 . The system according to claim 11 , wherein a change in a physical instrument driver includes adding at least one modified function.
14 . The system according to claim 11 , wherein the at least one modified function is modified from the at least one of the one or more functions.
15 . The system according to claim 14 , wherein the at least one modified function is added in a second location following the first location in the memory structure.
16 . The system according to claim 15 , wherein the addition of the at least one modified function does not change the location of the one or more functions in the first location in the memory structure.
17 . The system according to claim 16 , wherein the memory structure further comprises a vtable.
18 . The system according to claim 17 , wherein the addition of the at least one modified function does not change a location of the one or more functions in the vtable.
19 . The system according to claim 5 , wherein the one or more functions is included in a base programming class of functions, and the base programming class is inherited from an extended class of functions including the one or more additional functions.
20 . The system according to claim 11 , wherein the one or more functions is included in a base programming class of functions, and the base programming class is inherited from an extended class of functions including the at least one modified function.
21 . The system according to claim 2 , wherein the computer system includes a general-purpose computer system.
22 . The system according to claim 1 , wherein the one or more test instruments are coupled to one or more devices under test.
23 . The system according to claim 22 , wherein at least one of the one or more test instruments is programmed by the test program to apply a test signal to at least one of the one or more devices under test.
24 . The system according to claim 1 , wherein the system is part of an automated test system.
25 . The system according to claim 1 , further comprising a virtual instrument entity adapted to execute the procedure on the one or more test instruments, wherein the virtual instrument entity accesses the one or more test instruments through the respective one or more driver programs.
26 . The system according to claim 25 , wherein the virtual instrument entity includes one or more functions.
27 . The system according to claim 26 , wherein the test program is adapted to access the one or more test instruments by accessing the one or more functions of the virtual instrument.
28 . The system according to claim 27 , wherein the test program is programmed to access the one or more instruments only through the virtual instrument.
29 . The system according to claim 25 , wherein the virtual instrument entity isolates the test program from programming interfaces specific to the one or more test hardware.
30 . The system according to claim 25 , wherein the virtual instrument includes a virtual instrument programming interface.
31 . The system according to claim 30 , wherein a change in the one or more test instruments does not produce a corresponding change in the virtual instrument programming interface.
32 . The system according to claim 26 , wherein a change in the virtual instrument entity does not produce a corresponding change in the one or more functions.
33 . The system according to claim 32 , wherein the one or more functions are loaded in a memory structure of a computer system.
34 . The system according to claim 33 , wherein the change in the virtual instrument entity does not produce a corresponding change in the memory structure of the computer system.
35 . The system according to claim 34 , wherein the one or more functions are located in a first location in the memory structure of the computer system.
36 . The system according to claim 35 , wherein the change in the virtual instrument entity includes adding one or more additional functions.
37 . The system according to claim 35 , wherein the change in the virtual instrument entity includes modifying at least one of the one or more functions.
38 . The system according to claim 36 , wherein the one or more additional functions are added in a second location following the first location in the memory structure of the computer system.
39 . The system according to claim 38 , wherein the addition of the one or more additional functions does not change the location of the one or more functions in the first location in the memory structure of the computer system.
40 . The system according to claim 39 , wherein the memory structure of the computer system further comprises a vtable.
41 . The system according to claim 40 , wherein the addition of the one or more additional functions does not change a location of the one or more functions in the vtable.
42 . The system according to claim 37 , wherein the change in the virtual instrument entity includes adding at least one modified function.
43 . The system according to claim 42 , wherein the at least one modified function is modified from the at least one of the one or more functions.
44 . The system according to claim 43 , wherein the at least one modified function is added in a second location following the first location in the memory structure of the computer system.
45 . The system according to claim 44 , wherein the addition of the at least one modified function does not change the location of the one or more functions in the first location in the memory structure of the computer system.
46 . The system according to claim 45 , wherein the memory structure of the computer system further comprises a vtable.
47 . The system according to claim 46 , wherein the addition of the at least one modified function does not change a location of the one or more functions in the vtable.
48 . The system according to claim 35 , wherein the change in the virtual instrument entity includes adding one or more additional functions.
49 . The system according to claim 36 , wherein the one or more functions is included in a base programming class of functions, and the base programming class is inherited from an extended class of functions including the one or more additional functions.
50 . The system according to claim 42 , wherein the one or more functions is included in a base programming class of functions, and the base programming class is inherited from an extended class of functions including the at least one modified function.
51 . The system according to claim 33 , wherein the computer system includes a general-purpose computer system.