TransAct POSJET 1500, Programmer'S Manual

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Programmer's Guide POSjet
®
1500 Codes and Commands
Nov-07 Rev M Page 143
Horizontal Graphics (Color Graphics)
The POSjet
®
1500 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 POSjet
®
1500 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 3 color plans. 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: The bar code generation and other graphic commands change graphics mode. The format
of the horizontal graphic command follows.
Function
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 white dot. While red, green,
and blue pixels set to zero form a black dot. For black print, 1 represents a black dot, while a 0
represents a white dot.
Note 2 More than one color may be set at a time. Setting the color to six would set green and blue
simultaneously. Where <length> is a byte specifying the length of the data including the format
byte.
<length> =
0 to 254 (255 is reserved for future use.)
Where <format> is a byte specifying the format of the graphics data.
<format> =
0 for raw data
1 for bit wise RLE compression
8 for byte wise RLE compression
254 for difference compression
255 for same as previous scan line data
Where <data> is the data bytes that define the graphics to be printed.