DO-178B Certifications for avionics software with Testwell CTC++ Test Coverage Analyzer
The norm DO-178B "Software Considerations in Airborne Systems and Equipment Certification" requires in section 6.4.4.2 a structural coverage analysis.
The objective of structural coverage analysis is to determine which code structure was not exercised by the requirements-based test procedures.
It is possible that the requirements-based test cases may not have completetly exercised the code structure.
For this reason structural coverage analysis is performed and additonal verification produced to provide structural coverage.
The structural coverage analysis should normally be performed on the source code.
In the case that DO-178B level A certification is required then additonal analysis must be undertaken on the object code to verify the correctness of the compiler-generated code sequences.
Both of these analyses may be performed with Testwell CTC++.
The requirements of DO-178B concerning the structural coverage analysis are summarised as follows:
|
DO-178B Ref.No. |
Description |
Level A |
Level B |
Level C |
| 6.4.4.2 | MC/DC is achieved | satisfied with independance | not required | not required |
|
6.4.4.2.a
6.4.4.2.b |
Decision Coverage is achieved | satisfied with independance | satisfied with independance | not required |
|
6.4.4.2.a
6.4.4.2.b |
Statement Coverage is achieved | satisfied with independance | satisfied with independance | satisfied |
|
6.4.4.2.c
6.4.4.2.b |
Data Coupling and Control Coupling is achieved | satisfied with independance | satisfied with independance | satisfied |
Testwell CTC++ analyses all necessary coverage levels for DO-178B:
MC/DC coverage:
Yes. Testwell CTC++ multicondition coverage gives it
Condition coverage:
Yes, it is a part of mulitcondition coverage and can be seen seperately in Testwell CTC++ eg. by "ctcpost -fc ..."
Decision coverage (also known as branch coverage):
Yes. Already Testwell CTC++ decision coverage instrumentation suffices.
Statement coverage:
When at least decision coverage is used, the statement coverage information can be concluded from the counters.