Epson Printer Interface Cartridge Operation Manual page 60

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.
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.
Because IBM Personal Computer BASIC will not send CHR$(26),
do not use that number in any of your graphics programs.
Those of you who have read the previous chapter will see that
designing graphics is much like designing user-defined characters.
Figure 8-4. Arrow design
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