[SOLVED] 7 Segment driver MAX7219 : handling the dot on floating numbers

I just tested that, and it's to be expected. Because of rounding, 99999999.1 ends up turning into 99999999.09999999403 when converted to a string with toString, and it's the last few digits that get shown.

If you want full control over it, convert it to a string manually yourself and pass the string in - eg: disp.set((99999999.1).toFixed(1))

I'll update the library with the new code :)