I looked it over, and found myself asking, "Why would one do that?" ... and similar questions.

They say there are many ways to "skin a cat."

I keep wondering why one would want that software-FIFO. There's probably good reason, but I've not found it.

Also, if I were presenting something to a group of neophytes, I'd certainly make it clear which assembler syntax was in use and what intrinsics there were. Not everybody knows what you assume they know, particularly when you assume certain, perhaps well-known, constants/parameters are known.

As for me, when you refer to any object, it had better be defined within that code body, else I'll confuse it with something with a similar name on some other MCU.

Another thing ... if you have routines that would be called putc or getc or the like in 'C', why not use those names in assembler? They're meaningful and easy to recall and that will help anybody to understand your code.

Long labels in assembler don't make for very pretty code, either, BTW. I try to keep my label names under 6 characters. That way they're easy to type and don't require a separate line or extra tabs, neither of which makes the code more readable. It makes the symbol cross-reference easier to use, too.

Creative use of upper and lower case is helpful, too. I know, I know ... those Pepsi-swilling tennis-shoe-wearing software geeks are too weak or lazy to use the shift-key any more than absolutely necessary. It's good excercise, though, and perhaps all the exercise they get.

RE