Epson FX-286 - Impact Printer, Руководство пользователя

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In the main graphics mode, however, the FX-286 prints only one
column of pins for each code it receives, and it
uses
only the top eight
of the nine pins.
Therefore, your graphics program must send codes for dot pat-
terns, one number for each column in a line. For each of those
columns the print head prints the pattern of dots you have specified.
To print figures taller than eight dots, the print head makes more
than one pass. It prints one line, then advances the paper and prints
another, just as it does with text.
To keep the print head from leaving gaps between the graphics lines
as it does between the text lines, the line spacing must be changed to
eliminate the space between lines. With a change in line spacing, the
FX-286 can print finely detailed graphic images that give no indication
that they are made up of separate lines, each no more than 8/72nd of
an inch tall.
Each pass of the print head prints one piece of the total pattern,
which can be as tall or short and as wide or narrow as you desire. You
don’t have to fill the whole page or even an entire line with your
graphics figures. In fact, you can use as little or as much space as you
like for a figure and put it anywhere on the page.
Graphics Mode
The graphics mode command is quite different from the other com-
mands covered so far in this manual. For most of the other
FX-286
modes, such as emphasized and double-width, one ESCape code turns
the mode on and another turns it off. ‘For graphics, the command is
more complicated because the code that turns on a graphics mode also
specifies how many columns it will use. After the FX-286 receives this
code, it interprets the next numbers as pin patterns and prints them on
the paper.
The FX-286 has several different graphics densities, but the first
exercises keep things simple by using only one. The code for entering
single-density graphics mode is ESCape “K” n1 n2. In BASIC the com-
mand is given in this format:
LPRINT CHR$(27)"K"CHR$(n1)CHR$(n2);
ESCape “K” specifies single-density graphics, and the next two num-
bers (n1 and n2) specify the number of columns reserved for graphics.
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