CRESTS/TESSC(SCT-CAST)

(CRESTS Embedded Software Testing on Simulated Computer)

Real-time embedded softwares are applied abundently in aerospace system; and these softwares include from the application softwares of strong professional feature to system softwares (for instance, real-time operating system core RTOS). Real-time embedded software testing is closely related to the features of real-time embedded softwares; moreover real-time embedded softwares are closely connected with hardwares; and real-time is required very strictly. TESSC (SCT-Cast) is a proprietory system developed specially for embedded software validation (verification) in space industry.

TESSC is composed of Host System and simulation processing module. Simulation processing module includes a duplication of target CPU (for instance, DSP3X) and support system. The duplication of target CPU executes ultimate binary codes of assembler language program, Ada language program and C language program. And support system controls the duplication action of target CPU and simulates the interface of lower-level hardware. Host system is applied for application testing and complete control, and also providing analog simulations of more complex environments. The ultimate binary codes of assembler language program, advanced language program and mixed language program have no need of any amendments, and are executed directly in the real target CPU duplication, also are applied in simulation system of target software real external apperceive environment.

The interface styles, application styles and the most main functions of CRESTS/ATAT have been reserved.



One most important feature of TESSC is target CPU dulplication and all the time relation related with it can be managed and controlled by support system and control system. That is to say, the action process of the target software on TESSC (including assembler language program, advanced language program) can be completely controlled. Moreover, TESSC can make exploration to target software interior specifically and exactly during testing; it can still have more software tests and have research on deep-seated problems of target softwares.

System test, the test for the systems incorporated with softwares and hardwares. In terms of software tests, the result of this testing method is the system behavior including software behavior. So it is hard to identify software behavior features, and usually is regarded as one of the methods for validating tests; while TESSC can make up this vacancy.

TESSC features are as following:

·TESSC provides real CPU;

·simulate real target CPU I/O interface;

·The ultimate binary codes of target softwares (including assembler language program, advanced language program, mixed language program) have no need of any amendments, and are executed directly in the real target CPU duplication;

·support setting breakpoints in all the memory and all the I/O address space;

·support setting breakpoints at any time during target software running;

·support faults injection from CPU interior and inferior environments, aiming at target softwares (including assembler language program, advanced language program, mixed language program); realize closed-loop running of tested application programs. In this way, no devices are needed to be brought in during software tests;

·support coverage rate analysis running on the basis of real target CPU dulplication;

·the requirement for real-time is very strict;

·the system is reusable;

·preserve interface style, apllication style and most main functions of CRESTS/ATAT, TESS;

·Although tested programs are running on real CPU, TESSC is also no need of having stubbing to tested programs (or SCT-Cast can having stubbing to tested programs ).

·have programming simulation to CPU I/O behavior and surrounding hardware behavior; and realize closed-loop running of tested application programs. In this way, no devices are needed to be brought in during software tests;

·support assembler, C language and Ada language.

TESSC can meet the requirements of interior testing and debugging in embedded software development period and take-over period test; and can provide reliable and reproducible testing process and testing report of testing problems for testers, tested party and superior responsible institutions.

Under this platform, virtual target computer environment, program structure analysis, software quality measurement, supporting structure test, faults injection, full-digital simulation, software analysis and testing final report.