Awesome! This still gives me the glitchy thing when pressing 0 or DEL, although I admit I forgot to test it on real hardware yet sorry Did it happen for you JWinslow?

Ok, this is going on my calc right now, gonna play some Sudoku before going to bed. Seriously, all the new additions the past few days are just amazing, really nice work! The only thing that is a bit weird is the cursor in the menu, why is it pointing away from the choices? It looks like it should be the other way around.

And for the record, [ 0 ] / [Del] work fine on my OS 1.19 83+ as well.

EDIT: Maybe pressing [2nd] or [Enter] (or any key) should take you back to the main menu instead of only [Clear] when you win. I was also trying to think of a way to have pencil marks show up on the full board, and maybe it's a bit overkill but what about having a 3x3 grid where each dot is a #? For example: (X = on/black pixel, 0 = off/white pixel)
X0X
000
0X0
..would show that 1, 3, and 8 have been marked.

Anyway, i was never that great at Sudoku, maybe now i'll get a little better

I finally downloaded this so I'll get it on my calc to play when I have some extra time

(Not that I'm good at Sudoku, though )