TransAct Ithaca 280 Programmer's Manual page 131

Programming Codes
Horizontal Graphics (Color Graphics)
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The iTherm 280 Printer supports graphics sent as horizontal scan lines. Individual scan
lines of graphic data are sent to the printer one line at a time. Although the iTherm
Printer only supports two colors, the horizontal graphic command interface gives full
color support for printer graphics. Full color support is provided to establish a full color
standard for future printers. Color data is sent in one of three color planes. Typically, a
red plane or scan line is sent, then green and blue. The sequence of lines defines one
row of dots that is printed on the paper.
The horizontal graphic commands do not include resolution information. Therefore, only
once before sending graphics data, set the graphics resolution by sending the [ESC] *
command with a zero length (no data). The graphic resolution sets the internal graphic
mode of the printer. The printer stays in graphic mode until it is changed by another
command. Note that the bar code generation and other graphic commands change
graphics mode. The format of the horizontal graphic command follows.
For additional information on color graphics, see Chapter 7, ―Color Graphics.‖
[ESC] h Process horizontal graphics data
ASCII [ESC] h <color> <length> <format> <data>
Hexadecimal 1BH 68H
Decimal <27> <104>
IPCL None
EPOS None
Description The [ESC] h <color> <length> <format> <data> command processes
horizontal graphic data, where <color> is a byte that specifies the color of
the data being sent.
<color> = 0 Use Previously Selected Color
1 Red
2 Green
4 Blue
Note 1: Red, green, and blue pixels set to one at the same location result
in a white dot, while red, green, and blue pixels set to zero form a black
dot. For black print, one represents a black dot and zero represents a
white dot.
Note 2: More than one color may be set at a time – for example, setting
the color to six would set green and blue simultaneously.
<length> = byte specifying the length of the data including the format byte, ranging
from 0 to 254 (255 is reserved for future use.)
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iTherm
Rev K
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280 Programmer's Guide
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280
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