When developing libraries and other complex applications, I find that I often need to exercise specific parts of the library/application as it is being developed.
One way to do this is to write specific test code to exercise functionality. Another is to provide an interactive command line interface to achieve the same.
Until recently I hard coded these testing code CLI for each application. I now have a simple class that enables a flexible and consistent CLI.
A logic analyzer is an electronic instrument that captures and displays multiple signals from a digital system or circuit on a common time base. It is a really useful tool for debugging circuits and communications links. However, the cost of brand-name logic analyzers runs into hundreds of dollars and can be really hard to justify for hobby use.
Arduino++ 