TransAct Ithaca 8000, Руководство программиста

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Ithaca
®
8000 Color Graphics Ithaca
®
8000 Programmer’s Guide
100-06908 Rev D Page 239
Printing Graphics
The Ithaca
®
8000 Printer has bit-image graphic capability and a full PC-compatible
graphic character set. The bit image format is similar to that used on other personal
computer printers. Three modes of operation are available. Single-density is the fastest
mode. It makes a single unidirectional 60 dpi print pass. Full-speed double-density
mode makes two passes with a half-dot offset. Full-speed double-density mode is half
the speed of single-density mode, but it prints at 120 dpi. Half-speed double-density
mode is half the speed of full-speed double-density; however, the print quality is
enhanced.
Character Graphics
Character graphics is the term for joining individual characters together to produce a
mosaic of characters that form a graphic image. The simplest method uses an * (or any
other character) to form an image. For example, ITHACA
®
might be formed as follows.
*** *** * * ** *** **
* * * * * * * * * *
* * ***** **** * ****
* * * * * * * * * *
*** * * * * * *** * *
Figure 9 Example of Character Graphics
The extended character set of the printer supports line graphic characters that can be
combined to form windows and other shapes. For the shapes to join from line to line,
the spacing must be set properly.
All characters are in a nine-dot-high character cell. The dots are 1/60 inch apart.
Therefore, the line spacing should be 10/60 or 1/6 inch. The set fine line space
command can be used to set the line spacing. If possible, the spacing should be
reduced slightly to overlap the rows, which prevents any white spacing from appearing
between the lines. The following example illustrates the use of extended character
graphics.