
Chapter 7
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With this printer you can create new characters and symbols, download their dot data, and
have themprinted inplace of selected characters in theregular character set. Characters that
can be generated in this way range from simple but useful symbols like the check mark
through to complex Chinese or Japanese characters.
Regular characters are permanently stored in the printer’s ROM, but characters you design
are downloaded and stored in RAM for use.
Before you start to define your own characters, you must set the DIP switch 2 to OFF.
Otherwise, the RAM is used to store the input buffer, and the download commands are
ignored.
DEFINING YOUR OWN 24-DOT CHARACTERS
Designing and printing your own characters has two requirements: first, designing the
shape of the character, calculating the data necessary to make the shape, and sending that
data to the printer, and secondly, sending the command to print the downloaded characters
instead of the regular characters. There are a number of design constraints for download
characters:
. The matrix or grid on which you design the characters depends upon the print mode as
shown below:
Character mode
Horizontal
Vertical
Pica characters 31
24
Elite characters 27
24
Semi-condensed
19 16
Proportional 37
24
Super/subscript
19
16
Proportional super/subscript 37
16
. The minimum width of ,acharacter is ilve dots.
. Dots cannot overlap.
. You may define any position in the ASCII table upto 127 characters.
Photocopy the grid in Figure 7-1 to help design your new characters. We will use a tiny
representation of a telephone symbol for our example.
Chapter7 DOWNLOAD CHARACTERS 67