TL;DR

At the very last, some cards.

In the specific, eight decks of cards like the following ones:

ace of hearts seven of diamonds

ten of clubs queen of spades

All cards here.

The three led slots are used to optionally host one single icon each (hops, corn, acorn). They’re like bits, so for three slots you get eight combination and eight decks (should you need it).

The icons are CC BY 3.0 from game-icons.net:

Soon I’ll hopefully share the script to do this…