First of all thank you very much for you comment. About your question now: if you use a common anode display there is no need to connect the Arduino GND pin to the board as the digital pins act like it. I hope you can make it work and if you have any other question please feel free to post another comment.
Thanks Kola. I defined the functions because it was easier (for me at least) to keep track of what each chunk of code does anyway I am glad you liked it !
Thank you very much. Great work !
Make an Operating System (no programming)
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