Epson SQ-2550 User Manual page 141

User-defined Characters
An example will show how to specify nl and n2. If, for
instance, you wanted to redefine the characters A through Z,
would be A (or ASCII code 65) and n2 would be Z (or ASCII
code 90). So the command ESC & 0 AZ (followed by the
appropriate data) would replace the entire alphabet of capital
letters.
Following the specification of the range of characters to be
defined in this command are three data bytes (d0-d2) that
specify the width of the character and the space around it. The
left space (in dot columns) is specified by d0, and the right
space is specified by d2. The second byte (dl) specifies the
number of columns of dots that are printed to make up the
character. By varying the width of the character itself and the
spaces around it, you can create proportional-width characters
that print at draft speed. The table below shows the maximum
values for these bytes.
Mode
Draft
Letter Quality 10 cpi
Letter Quality 12 cpi
Proportional
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, your
printer expects dl x 3 bytes of data to follow d2.
An example character definition program should make this clear:
10 LPRINT CHR$(27)"X0"
20 LPRINT CHR$(27)"&"CHR$(0);
30 LPRINT "@@";
40 LPRINT CHRS(1)CHRS(9)CHRS(1);
50
FOR I=1 TO 27
4-26 Software and Graphics
d1
(maximum)
9
29
23
I
37
nl
d0 + d1 + d2
(maximum)
12
36
30
42