Board support code in TG9541/STM8EF has supported boards with 3 or 4 digit LED displays for several months now, and output of text (e.g. numbers) on a LED display is simple.

However, since support for the W1401 was added, there are now devices with "structured" LED displays. With "structured" I mean different color, size, or grouped in rows or columns.

As an application programmer I want character output to be simple, and I want the code to look the same no matter if it outputs to the console or to grouped digits of LED displays (that's also important for testing). In the future there might be devices with LCDs, or serial data output, and code should "just work".

The easiest way to achieve that, is to use whitespace as some kind of "output element separator" ("." and ".R" should have the same effect). <CR> can act as "return to first element". Of course, this will make the code more complicated than simply spilling text over to the next digit, no matter where it is, but it will make writing applications a lot easier.

If someone has a different idea how to do it, I'd like to hear about it!

EDIT1: OK, since I didn't hear about it, I implemented a prototype. It works quite well, but an extra state is necessary to handle CR consistently (whitespace or CR should move to the next display group only once).

EDIT2: I tested the feature on boards with 1, 2, and 3 display groups, and updated the W1219 and W1401 docs on GitHub. Output of numbers and character strings on grouped LED displays is now really easy!