Since I wanted a minimalist build with no buttons on my clock, I decided to throw in a GPS to get the time sync from!
Short list of features:
* Time sync from GPS (Ublox NeoM6 module, but can be any)
* Timer interrupt to refresh/multiplex the tubes in a stable way.
* Fully non-blocking tube multiplexing (no delay()-functions)
* Uses the Time class, rather than millis() to keep track of time
Overall I think the code is cleaner and easier to read, compared to the original example code.
You can find the code on GitHub:https://github.com/maximevince/arduinix_gps_timer_isr
Let me know if you like it, use it, ... or send me a pull request on GitHub if you improved the code!