lines, but no dots can overlap. In low-speed double density dots can
be placed on vertical lines and they can overlap.
Now look at
the
figure designed for high-speed double density. It
should point you in the right direction for your own designs.
Figure 8-4. Arrow design
Although the top pin (value
128)
can be used in any graphic you
design, this exercise uses only seven pins (values
l-64).
This was done
because the graphic has twenty-one rows-using only seven pins pro-
duces three lines of seven rows each.
After plotting all the dots as in Figure
8-4,
you calculate the num-
bers for each pin pattern by dividing the design grid into separate print
lines. For the arrow design, the grid was divided into three lines,
each
seven
dots high. Then each column was examined and the sums of the
pin values determined. This process for the first line is shown in Figure
8-5.
The pin values are on the left side and the sums are at the bottom
of each column.
Those of you who have read the previous chapter will
see that
de-
signing graphics is much like designing user-defined characters.
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