IntelliTech Intellibar M412, Справочное руководство

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HP PCL Graphics Commands 9-7
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delta row compression
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adaptive compression
The choice of compression methods affects both the amount of code needed to generate a
raster graphics image and the efficiency with which the image is printed. Compressed data
formats allow for efficient transfer of data from the host system to the printer. However,
compressed data formats do not reduce the amount of printer memory required to produce
an image.
Transfer Raster Data
The transfer raster data command is used to transfer a row of raster data to the printer.
ESC*b#W [raster data]
Decimal: 027 042 098 # 087
Hex: 1B 2A 62 # 57
The value field (#) identifies the number of bytes in the raster row. These bytes are
interpreted as one row of raster graphics data that will be printed at the current Y position
at the left raster graphics margin. Upon completion of this command, the current active
position is at the beginning of the next raster row at the left raster graphics margin.
Within the raster data, each bit describes a single dot. The most significant bit (bit 7 is the
most significant, bit 0 is the least significant) of the first byte of data corresponds to the
first dot within that row. If a bit is set to 1, the corresponding dot will be printed. Each dot
of the raster data is expanded according to the specified raster resolution.
Raster graphics is independent of the text area and perforation skip mode, i.e., these
boundaries are ignored.
Raster graphic images are limited to the printable area; images that extend beyond the
printable area are clipped.
End Raster Graphics
The end raster graphics sequence signifies the end of the transfer of a raster graphic image.
ESC*rB
Decimal: 027 042 114 066
Hex: 1B 2A 72 42