space=
===
a a b b
c c d d e e
f f g g
h h i i j j
k k l l
m m n n o o
p p q q
r r s s t t
u u v v
w w x x y y
z z
A A B B
C C D D E E
F F G G
H H I I J J
K K L L
M M N N O O
P P Q-Z (unused)
0 0 1 1
2 2 3 3 4 4
5 5 6 6
7 7 8 8 9 9
Punctuation and math symbols are not used.