Robin2:
What exactly do you want the student to gain from your tutorial?Is it "how to use an LCD"?
OR,
Is it "how to write code to calculate time"
Whichever it is, it seems to me that the other part is just a confusion.
It's "how to make a rudimentary clock". It's not much of a clock if you can't see what time it is.
Actually, now that I think about it, maybe I should pull out the "display the time" part into its own function.
I know that the code I posted is for a count-up timer rather than a clock. The first step in my tutorial will be to make a count-up timer. In the next step, I will add buttons to allow the time to be set, thus turning it into a clock.
And I, also, don't like your abbreviated variable names. IMHO long descriptive names make it possible to read a program like story. For example secondsValue rather than ss
...R
I see your point. But I don't want my code to end up like this, either: https://www.youtube.com/watch?v=nJ8Tq5EotaE
Would day, hour, minute, and second work? Or would they conflict with some reserved words or something? I know that min for minutes wouldn't work, because min is used for something else in Arduino-land.