User-defined Characters
A value of
136
is suitable for all characters that use the top eight
pins, start in column
1,
and finish in column
9.
For a character of
the same width, but printed with the bottom eight pins,
al
should
be
8.
For any other character, follow these rules to calculate
al:
1.
If you design a character narrower than nine columns, you can
balance the number of empty columns on either side with the
following method: starting with
al
equal to
8,
subtract 1 for
every blank column on the right and add
16
for every blank
column
on the left.
2..
If the character uses the top eight pins, add
128.
For example, if a character uses the top eight pins, starts in column
3,
and ends in column
7,
the calculation is as follows:
l start with
al
=
8
l subtract 2 for two blank columns on the left, giving
al
=
6
l add
32
for two blank columns on the left, giving
al
=
38
l add
128
to print with the top eight pins, so that
al
=
166.
Printing
userdefined
characters
If you entered the example program on page
4-25
you defined a
heart and placed it in the
RAIvI
location for ASCII code
64
(replacing the at sign). You can now print out-a three-line sample of
your work. The first and third lines (printed by lines
170
and
210
of
the program) print the normal at sign; the second line (line
190)
prints the heart that you defined.
Run the program to see the printout below.
4-26
Software
and Graphics
