Density Varieties - Epson FX Series User Manual

for form feed-CHR$(12)-to the printer, the computer system inter-
cepts it and sends instead a series of line feeds-CHR$(10). It does this
whether the CHR$ commands represent true commands, parameters
for commands, or data. It screens out all instances of its reserved
numbers. You can see how this could upset the printing of graphics. In
this example, you would get pins 2 and
wanted pins 3 and 4 (whose sum is 12).
Does this mean that if your computer system transmutes some con-
trol codes, you can't use the pin patterns of those numbers in your
graphics programs? Well . . . yes, it does. At least, not via the usual
CHR$ function. But you can often design around these problems by
using other numbers with similar patterns, or you can POKE the trou-
ble codes directly to the FX. Learning how to cope with these problems
is part of learning how to use the printer with your system. See
Appendix F for help.

Density Varieties

The FX printer offers you the 16 text densities that we printed out as
Figure 5-2, and seven graphics density settings that we list later in this
chapter (Table
11-1).
specifying it in the Master Select ESCape code sequence, and that you
can switch densities later by changing one parameter in that code.
The FX has a similar command sequence for specifying and chang-
ing modes for its graphics densities. Here is the commands format:
LPRINT CHR$(27)"*"CHR$(m)CHR$(n
where m indicates the number (0 - 6) of the desired Graphics Mode,
and the settings n
seven modes include six densities and the two speeds for Double-
Density.
Before you try out any of the new graphics density settings, record
a sample line of Single-Density. To do so, enter this new program:
20 A$=CHR$(27)+"*"+CHR$(0)+CHR$(50)+CHR$(0)
30 B$=CHR$(85)+CHR$(42)
40 LPRINT A$;: FOR X=1 TO 25: LPRINT B$;: NEXT X
50 LPRINT "J&SINGLE-DENSITY GRAPHICS ";
60 LPRINT A$;: FOR X=1 TO 25: LPRINT B$;: NEXT X
70 LPRINT
80 LPRINT CHR$(27)"@"
Remember that you can choose a text density by
and n are the usual graphics width settings. The
1 2
(whose sum is
4
)CHR$(n );
1 2
when you
10)
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