Modular Coding - What types of code portions to convert into library files? Rationale and methods?

Question

I'm working on documentation and combining 2 pieces of code for testing parts of a larger project.

I'm supposed to comment and make the code very clear to people who will use it later and make sure it's modular. I'm supposed to make header files, to reference function chunks in the main code from just the #include(s).

I understand in C++, that the convention is that for each header files(?), .h, there is a .cpp, where the .h is the header file that declares all the content, and that the .cpp is where you define the .h, ie. implementation.

My supervisor told me to put more parts of the code into library files, because additional components will be added in the future -

but confused because all the length comes from using already existing library files, just a specific pattern of calling pre-defined functions.

If I put the files into a .h, how do I reference all the calls? Make a void setup () {}?

The compiled code is 348 lines right now. All it has are some #include(s), code to calibrate and read from 2 different sensors using I2C and SPI protocols, with 1 shared master an Adafruit Bluefruit nRF52832, and comments with links to datasheets.

The bulkiness is in the set-ups and the different ways to represent data (have 24 lines just to print out data from 1 sensor).

Should the entire code be just calling built in functions from a library file? So people who read the code don't see the details so much?

Answer 1

It's very subjective what should and shouldn't be put in a library.

I use the simple rules:

• If it's an atomic piece of code like a hardware driver, it's a library.
• If it's something that could be used in multiple sketches, it's a library.

Maybe things like configuration options could be put in a header file (not a library - a header file in the sketch folder).

You could maybe split portions of your sketch into C++ files or INO files within the sketch (not a library - files in the sketch folder, and using INO files is easier since you don't need header files, the IDE does it all for you) to group things logically together and make it easier to manage (all the LCD code in one file, all the temperature sensor code in another file, that kind of thing).