1
m m, m, m, m. m. m m, m. m m
64
32
16
4
2
1
Tolal
ASCII Code WRONG!
Descender
Start column
End column
M, = Descender l 128 + (Slat1 * 16) + End
i
Figure 6-6. cots cannot overlap; those in immediately adjacent
“half columns” will be ignored when the character is printed.
W Add up each column of dots
Now it’s time to give our creative side a break and get down to
some basic arithmetic. That’s where the numbers down the left
side of the grid come in. Notice that there is a number for each
row of3 dots and that each number is twice the number below it.
By making these numbers powers of two we can take any com-
bination of dots in a vertical column and assign them a unique
value. Some examples will make this clearer. As shown in
Figure 6-7, if we add the numbers for the dots that print in a col-
umn, the sum will be a number in the range of 0 to 255. Each
number from 0 - 255 represents a unique combination of dots.
128
64 0 - 64
32 0 - 32 . - 32
/ 16 0 16 -
/ - 8 O-8
4 o-4
! 2 o-2 O-2
1 O-l
~ ___
Sum 103 58
O-128
0 - 64
l - 32
0 - 16
o-8
O-4
o-2
O-1
255
Figure 6-7. By adding the values of each dot in a column, you’ll get
a unique description for any combination of dots.