Click the "Pi>" to begin. Click text wrap to change the style the pi shows. (o is on and - is off) When on it will fill the screen, when off you will not the beginning of pi, but only the most recent digits. It will be longer with text wrap off, but you will not be able to see the full number. What is there is very long.
I used the same script I wrote for typewriter. (https://scratch.mit.edu/projects/145331147/) - Typewriter For very many digits of pi, I got it from here: http://www.piday.org/million/ all but pi is from me (the font was through inkscape).