Fantastic! Using the combination of ‘serialoscd’ and the dialout add group, I was able to get the grid and arc recognized in Processing and the grid in Supercollider.
Overall as a new Linux user I am both pleased and frustrated (with Linux). I love all the flexibility and the different open-source options available, but these nitty gritty things can be difficult to sort out sometimes, and I just don’t have enough of a background to know things to try (bluntly, if I don’t know the commands exactly I am basically out of luck ha ha)
Thanks again!!!