Epson SQ-2000, Operating Manual

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Note:
The entire range of ASCII decimal codes (from 0 to 127) can be
used for user-defined characters, but a caution is in order. Char-
acters with ASCII decimal values below 32 are usually reserved as
control codes by both your computer and your printer. While
these characters can be replaced by user-defined characters, it
should be avoided because of the effect on the normal control
codes.
To see how to specify
nl
and
n2,
let’s use an example. If, for
instance, you wanted to redefine the characters A through Z, nl
would be “A” (or ASCII decimal 65) and
n2
would be “Z” (ASCII
decimal 90). So the command <ESC> “&” <NUL> “AZ” (fol-
lowed by the appropriate data) would replace the entire alphabet
of capital letters.
In some instances, you may want to redefine a single character.
In this case,
nl
and
n2
would have the same value. Our example
at the end of this section does just that; it defines only the “A”
character which is replaced by a new letter A.
Following the specification of the range of characters to be
defined in this command is the data that defines the characters.
The data is in this form:
do, d1, d2, Dl, D2, . . . Dd1x3
The first three bytes are used to specify the width of the char-
acter and the space to be allowed on either side of it. The left
margin (in dot columns) is specified by d0 and the right margin is
specified by
d2.
The second byte
(d1)
specifies the number of
columns of dots that are printed by the character. By varying the
width of the character itself and the spaces around it, you can
actually create proportional width characters that print at draft
speed.
When defining draft quality characters, the number of printed
columns
(dl)
cannot exceed 9, and the sum of
d0
+
dl
+
d2
cannot
exceed 12.
The last part of the character definition is the actual data that
defines the dot patterns for each character. Since it takes three
bytes to specify the dots in one vertical column of dots, the
SQ-2000 expects d1x3 bytes of data to follow d2.
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