Happy that you found the speech useful.

Thank you Cesar_Santos. Timing constraints in a host environment do not make any sense. The only thing you can do is sequencing tests through Mock objects. In this case the Mock objects may test that the sequence of actions were executed as per spec (ie. having a state machine in the mock and check that it passes all transitions). I can think of ways to do timing constrained tests using Unity to execute target tests and use a hardware timer register to check timings. But still I am not sure if this would be realistic ie. passing the test implies that the code is correct. In complex systems interrupts and other stuff runs and may throw you out if you make a mistake. I prefer to handle these problems on paper. Design it right into the paper and make it sure that it will work by design, if this is possible.

Thank you Iramage, yes LLVM is another option. Creating test cases for legacy code is a pain. Myself I am doing partial testing on critical modules which through my experience I believe are more probable to fail. At the end I want to reduce development time, creating tests only for the most difficult parts of the code helps me to have peace of mind as the rest of the code is manageable.

Dear MJ,
I am not using any code coverage tools, but I think GCC has such a free tool (gcov). The source will be unaffected but the compiler will inject its own instructions in the binary file to gather the data. I guess you are not supposed to ship this code to the field and later on gather such data (although you could). I would not use coverage tools in production code (ie that runs into the field), only to support lab tests as part of test phase (depending the project). I do not know how other tools work.
TDD has the advantage of providing functional coverage (which is a super-set), is automated after the completion and do not disrupt production code in any level.

As Ilias already mentioned, one can use gcov/lcov if using the GNU Compiler Collection. However, another great alternative is scan-build, part of the clang/llvm suite, https://clang-analyzer.llvm.org/scan-build.html

Glad to see that the provided information was useful. If you have specific problems we can discuss them.

I'm doing my test stuff with ceedling which is using CMock and Unity for the test stuff. It's very easy to setup. Maybe you want to give it a try (http://www.throwtheswitch.org/ceedling)

I personally haven't tried other ones. I guess there should not be much different. I know that Unity is very similar, and that's why CppUTest has conversion scripts. The important thing I would like to have is to be able to test double through the linker instead of having to modify sources etc.

In my video I also show part of the more complex queued SPI module that Coldfire has. I also have created USB tests as well and actually I can say USB implementation of the mocks was much simpler than Queued SPI. In a presentation like this it is not possible to show all the parts and the complexity. The reason I found USB easier, is that the hardware engine provides a packetized approach (per USB also principles) that was much easier to replicate. So although theoretically we have more complex hardware, it is not necessarily more difficult to mock. For standard microcontroller applications you use SPI, I2C/TWI, Uarts, Timers, maybe DMA. You can cover lots of these as standard devices. Of course if you change platforms around all the time, yes then you have to re-develop or modify. On the other hand having programmable logic with standard components (or your own components) can keep the longevity of the code easier as the hardware is controlled by you (another approach though). You may also stick with TDD up to the driver level, depends on how confident you are about them. Sometimes of course there is no option.

Do you mean actual timing or sequencing? Mocks will allow you sequencing. Timing does not make sense in absolute ways on your PC, your system will differ. If you are concerned about relative timings the method proposed on the top level could work also. Can you provide an example case to help me understand your problem?